2g Health Protection and communicable diseases

Question 1

What is Incubation?

Answer 1

The time interval between initial contact with an infectious agent and the appearance of the first sign or symptom of the disease in question.

Question 2

What is Communicability?

Answer 2

: Period of communicability is the time during which an infectious agent may be transferred directly or indirectly from an infected person to another person, from an infected animal to humans, or from an infected person to animals. Also known as the ‘infectious period’.

Question 3

What is the Latent Period?

Answer 3

The period between exposure and the onset of the period of communicability. This may be shorter or longer than the incubation period.

Question 4

What is Susceptibility?

Answer 4

The state of being susceptible (easily affected/infected). A susceptible person does not possess sufficient resistance against a particular pathogen to prevent contracting that infection or disease when exposed to the pathogen.

Question 5

What is Immunity?

Answer 5

The condition of being immune, protected against an infectious disease conferred either by an immune response generated by immunisation or previous infection.

There are 4 types of immunity:
Active
Passive
Specific
Required

Question 6

What are the different types of immunity?

Answer 6

Active
Passive
Specific
Required

Question 7

What is active immunity?

Answer 7

Resistance developed by a host in response to a stimulus by an antigen (infecting agent or vaccine), usually characterised by antibody produced by the host.

Question 8

What is passive immunity?

Answer 8

Immunity conferred by an antibody produced in another host and acquired naturally by an infant from its mother or artificially by administration of antibody-containing preparations e.g. anti-serum or immunoglobulin.

Question 9

What is specific immunity?

Answer 9

A state of altered responsiveness to a specific substance acquired through immunisation or natural infection. In certain diseases this protection can last for the life of the individual.

Question 10

What is aquired immunity?

Answer 10

Resistance acquired by a host as a result of previous exposure to a natural pathogen or foreign substance for the host e.g. immunity to measles following measles infection.

Question 11

What is herd immunity?

Answer 11

The level of immunity in a population which prevents epidemics, based on the resistance to infection of a proportion of individual members of the group sufficient to prevent widespread infection amongst non-immune members.

The proportion required varies according to agent, transmission characteristics and distribution of immune and susceptibles within the population.

Question 12

What is surveillance?

Answer 12

The continued watchfulness over the distribution and trends in the incidence of disease through the systematic collection, consolidation and evaluation of morbidity and mortality reports and other relevant data’

Question 13

What is the purpose of surveillance?

Answer 13

Allows individual cases of infection to be notified and collated

Measures incidence of infectious disease, with changes potentially indicating an outbreak

Tracks trends in occurrence and risk factors of an infectious disease allowing targeted interventions

Enables priority setting and planning of control measures e.g. to a particular region

Evaluation of existing control measures

Syndromic surveillance may detect the emergence of new infections of public health importance.

Question 14

What are the principles of good surveillance?

Answer 14

Start with a good case definition:
Must include clinical and/or microbiological criteria
Must be sensitive enough to detect cases, but also specific enough to prevent too many ‘false positives’. May include different levels of case definition e.g. ‘possible’, ‘probable’ and ‘confirmed’.

Collect data:
Multiple data streams may be used in combination to gain extra info (e.g. disease burden, high-risk groups)
Data collection should be systematic (systematic, regular and uniform)

Data analysis:
Data should be analysed to produce statistics: by time, place and person.
Care should be taken with timeliness, completeness, representation

Distribution of results:
Results should be distributed to those who require it, for instance via national bulletins (e.g. in national communicable disease epidemiology reports such as PHE’s Health Protection Report).

Implement actions and then continue surveillance to evaluate actions taken.

Question 15

What are the different types of surveillance?

Answer 15

Active surveillance
Passive surveillance
Syndromic surveillance
Sentinel surveillance
Enhanced surveillance

Question 16

What is

Answer 16

Active surveillance

Special effort to collect data and confirm diagnoses to ensure more complete reports, such as surveys and outbreak investigations
Encompasses formal and informal communications (such as phone calls or internet searches to seek information).

Question 17

What is Passive surveillance?

Answer 17

Use of routine sources of information such as notifications, laboratory reports, and Hospital Episode Statistics (HES).

Question 18

What is Syndromic surveillance?

Answer 18

The monitoring of symptoms, signs or syndromes instead of confirmed diagnosis.

Traditional public health surveillance relies on clinicians notifying public health authorities about diseases, which can lead to time delay from the reporting clinician or awaiting diagnostics.

By collation and analysis of real-time health data (such as presentations to primary care with a particular symptom e.g. influenza-like illness, rather than clinician notified diagnoses) which may indicate an important public health threat, ‘Syndromic surveillance’ allows for the earlier detection of outbreaks or health threats than would normally occur using traditional notification systems, and therefore earlier targeted action (CDC MMWR 2004).

Question 19

What is Sentinel surveillance?

Answer 19

Rather than collecting data from all notifying clinicians, only a sample are asked to report data at a regional or national level, on a regular (e.g. weekly/monthly) basis.

Question 20

What is Enhanced surveillance?

Answer 20

Enhanced surveillance is the collection of data above that collected for routine surveillance, generally at a patient level and often to design or evaluate an intervention or to aid control of more important health hazards.

For example, gaining epidemiological as well as microbiological information about MRSA bacteraemia cases in order to target and evaluate the effect of healthcare interventions on the incidence of the infection

Question 21

What are some examples of sources of surveillance data?

Answer 21

Statutory notifications
Laboratory reports
Serological surveys
Sentinel reporting systems Routine Primary and Secondary Care utilisation data, e.g. in England, Hospital Episode Statistics (HES) data
Death certificates (limited use in industrialised countries because few infectious diseases lead to death)
Enhanced Surveillance for infections of public health importance to combine epidemiological and microbiological data, e.g. meningococcal disease, TB
Vaccine use (COVER statistics in England)
Sickness absence
Epidemic reports, e.g. respiratory illness outbreaks in care homes are monitored as part of influenza surveillance
Media reports
Social media activity
Animal reservoir and vector studies

Question 22

What specific surveillance systems do we use for influenza?

Answer 22

Data collated by Respiratory Diseases Department (RDD) in the UKHSA.

Primary Care sentinel surveillance weekly returns service of consultation rates for influenza like illness (principle measure of flu activity).

Emergency Department attendances and NHS 111 (health advice helpline for the general public) cold and flu calls

Flusurvey.org.uk – online reporting of flu symptoms by the general public

Medical Officers of Schools Association (MOSA) scheme

Mortality data from Office for National Statistics (ONS) weekly death reports

Laboratory reports – Datamart surveillance scheme of positive influenza virology samples from selected laboratories; RCGP sentinel scheme – selected practices post nose and throat swabs from patients presenting with ILI for further characterisation by PCR

Hospital surveillance through the mandatory UK Severe Influenza Surveillance Scheme (USISS), monitoring critical care admissions of confirmed flu cases

Also, a USISS voluntary sentinel surveillance scheme for other hospitalised patients with confirmed influenza.

Question 23

What specific surveillance systems do we use for influenza?

Answer 23

Data collated by Respiratory Diseases Department (RDD) in the UKHSA.

Primary Care sentinel surveillance weekly returns service of consultation rates for influenza like illness (principle measure of flu activity).

Emergency Department attendances and NHS 111 (health advice helpline for the general public) cold and flu calls

Flusurvey.org.uk – online reporting of flu symptoms by the general public

Medical Officers of Schools Association (MOSA) scheme

Mortality data from Office for National Statistics (ONS) weekly death reports

Laboratory reports – Datamart surveillance scheme of positive influenza virology samples from selected laboratories; RCGP sentinel scheme – selected practices post nose and throat swabs from patients presenting with ILI for further characterisation by PCR

Hospital surveillance through the mandatory UK Severe Influenza Surveillance Scheme (USISS), monitoring critical care admissions of confirmed flu cases

Also, a USISS voluntary sentinel surveillance scheme for other hospitalised patients with confirmed influenza.

Question 24

What specific surveillance systems do we use for TB?

Answer 24

A statutory notification

Data collated and analysed by the UKHSA

Collects data on demographic, clinical and risk factor details, treatment outcome, drug sensitivity and species typing

Death certificates

TB incident and outbreak surveillance.

Question 25

What specific surveillance systems do we use for Healthcare-associated infections?

Answer 25

PHE previously had a surveillance programs covering:
Staphylococcus aureus (Methicillin resistant Staphylococcus aureus (MRSA) and Methicillin sensitive Staphylococcus aureus (MSSA))
Escherichia coli bacteraemia
Clostridium difficile infection

Enhanced surveillance of the first 4 infections is a mandatory requirement in regulated healthcare organisations in England and requires sign-off by the reporting organisation’s CEO.

Utilises the HCAI Data Capture System (DCS)

For MRSA bacteraemias, all positive cases must also have a Post Infection Review (PIR) completed, identifying how the case occurred and what actions could be taken to prevent a reoccurrence

Also allows capture of voluntary information such as the source/primary focus of MRSA bacteremia

Surgical Site Infection (SSI) Surveillance service also requires mandatory reporting of SSI in 4 categories of orthopaedics and voluntary surveillance in 13 categories of surgical procedures

Patient Administration Systems (PAS) can also contribute data.

Question 26

What are the specific surveillance systems that we use for STDs/STIs?

Answer 26

Genitourinary medicine clinical activity dataset (GUMCAD) – patient level data on diagnoses made and services provided from GUM and sexual health services
Chlamydia Testing Activity Dataset (CTAD) – patient level data on testing and diagnoses

HIV and AIDS new diagnosis database (HANDD) – new HIV diagnoses, AIDS and deaths

Survey of prevalent HIV infections diagnosed (SOPHID) – people seen for HIV care

HIV and AIDS Reporting system (HARS) – intended to replace HANDD and SOPHID

CD4 Surveillance Scheme – Reports of CD4 cell count measures from microbiology laboratories

National Survey of Sexual Attitudes and Lifestyles (NATSAL) sexual health behaviour survey

Hepatitis B is a notifiable disease

Antenatal screening for infectious diseases in pregnancy also provides data on HIV, hepatitis B, and syphilis (as well as Rubella susceptibility)

Blood, tissue and organ donors screening – NHS Blood Transfusion/PHE surveillance scheme includes hepatitis B and HIV.

Question 27

How do you evaluate a surveillance system?

Answer 27

1. Describe the public health importance of the health event under surveillance; consider:
   * The total number of cases
   * Incidence and prevalence
   * Indices of severity (death rate, case fatality ratio)
   * Can it be prevented?
2. Describe the surveillance system to be evaluated. what are is objectives?:
   * Detecting and monitoring outbreaks
   * Detecting and monitoring trends
   * Setting priorities and allocating resources
   * Describe the health event under surveillance
   * State the case definition
   * State the population and choice of denominator
   * Draw a flow chart of the system
   * Describe the components and operation of the system
   * What information is collected?
   * Who collects the data?
   * Time to collect data?
   * Mode of data transfer and storage?
   * Who analyses data?
   * How is the data disseminated?
   * Who is it disseminated to?
3. Discuss validity and repeatability of case definitions in various types of surveillance data
4. Indicate the level of usefulness by describing the actions taken as a result of data collected by the surveillance system. (e.g. useful in prevention and control of adverse event):
   * What actions are taken because of the data?
   * Who uses data to initiate action?
   * List anticipated uses of data.
5. Describe cost / resources needed to run surveillance:
   * Indirect
   * Direct: data collection/analysis/interpretation and dissemination.
6. Evaluate the quality of the surveillance system by assessing its key attributes:
   * Simplicity
   * Flexibility
   * Acceptability: to public/data collectors
   * Sensitivity: ability to detect health events
   * Timeliness
   * Representativeness: does it accurately describe incidence of health events in population by time/place/person.
7. List conclusions and recommendations:
   * Is the system meeting its objectives?
   * Address the need to continue/modify surveillance

Question 28

How do you evaluate a surveillance system?

Answer 28

1. Describe the public health importance of the health event under surveillance; consider:
   * The total number of cases
   * Incidence and prevalence
   * Indices of severity (death rate, case fatality ratio)
   * Can it be prevented?
2. Describe the surveillance system to be evaluated. what are is objectives?:
   * Detecting and monitoring outbreaks
   * Detecting and monitoring trends
   * Setting priorities and allocating resources
   * Describe the health event under surveillance
   * State the case definition
   * State the population and choice of denominator
   * Draw a flow chart of the system
   * Describe the components and operation of the system
   * What information is collected?
   * Who collects the data?
   * Time to collect data?
   * Mode of data transfer and storage?
   * Who analyses data?
   * How is the data disseminated?
   * Who is it disseminated to?
3. Discuss validity and repeatability of case definitions in various types of surveillance data
4. Indicate the level of usefulness by describing the actions taken as a result of data collected by the surveillance system. (e.g. useful in prevention and control of adverse event):
   * What actions are taken because of the data?
   * Who uses data to initiate action?
   * List anticipated uses of data.
5. Describe cost / resources needed to run surveillance:
   * Indirect
   * Direct: data collection/analysis/interpretation and dissemination.
6. Evaluate the quality of the surveillance system by assessing its key attributes:
   * Simplicity
   * Flexibility
   * Acceptability: to public/data collectors
   * Sensitivity: ability to detect health events
   * Timeliness
   * Representativeness: does it accurately describe the incidence of health events in population by time/place/person.
7. List conclusions and recommendations:
   * Is the system meeting its objectives?
   * Address the need to continue/modify surveillance

Question 29

How are the organisations that manage health protection generally structured?

Answer 29

There tends to be a tiered organisation with primary responsibility for health protection, progressing from local to national level. These tiers may be within a single or separate organisation.

In most countries, local health authorities conduct health protection activities at a local level such as receipt of case notifications, and investigation and control measures.

National health authorities tend to be responsible for data collation, analysis, and dissemination for action (surveillance). They may also support outbreak investigation and control, particularly if investigations cross regional borders.

There will also be a variety of organisations at each level that contribute to the efforts of the health protection team but whose primary function is not health protection, such as local government at a regional or sub-regional level, and food safety and veterinary health agencies at a national level.

Question 30

How are the organisations that manage health protection generally structured?

Answer 30

There tends to be a tiered organisation with primary responsibility for health protection, progressing from local to national level. These tiers may be within a single or separate organisation.

In most countries, local health authorities conduct health protection activities at a local level such as receipt of case notifications, and investigation and control measures.

National health authorities tend to be responsible for data collation, analysis, and dissemination for action (surveillance). They may also support outbreak investigation and control, particularly if investigations cross regional borders.

There will also be a variety of organisations at each level that contribute to the efforts of the health protection team but whose primary function is not health protection, such as local government at a regional or sub-regional level, and food safety and veterinary health agencies at a national level.

Question 31

What are the methods of infectious disease prevention in a clinical setting?

Answer 31

Hand Hygiene (for clinicians and the general public)
Use of personal protective equipment (PPE)
Handle and dispose of sharps safely
Dispose of contaminated waste safely (Or hot wash)
Managing blood and body fluids
Decontaminating equipment
Maintain a clean clinical environment
Prevent occupational exposure to infection
Manage sharps injuries and blood splash incidents
Manage linen safely
Suitable room/ward for patients with infections
Disinfection (in hospitals, nurseries, schools and nursing homes)

Tuberculosis screening services

Changes to risk behaviour - This can be achieved through general or targeted education campaigns, e.g. avoid sharing personal items, safe sex, careful disposal of needles / clinical waste with blood borne pathogens.

Question 32

What are ways in which infection can be prevented in the general public?

Answer 32

Hand washing
Safe clinical spaces (see the card on disease prevention in a clinical setting)
Education on personal hygiene and hygienic preparation of food
Children and adults in jobs likely to spread infection should stay away from school for 48 hours after any diarrhoea has stopped.
Routine and selective immunisation
Changes to risk behaviour

Question 33

Who is responsible for infection prevention?

Answer 33

In hospital - Infection control team

In Community - Health protection team

Question 34

What is a healthcare-associated infection?

Answer 34

Healthcare-associated infections (HCAI) are infections that occur in patients or health care workers as a result of healthcare interventions.

Question 35

Who is responsible for healthcare-associated infections in an organisation?

Answer 35

Overall responsibility rests with the chief executive and the trust board and the Director of Infection, Prevention and Control (DIPC).

Question 36

What is an infection control team?

Answer 36

A hospital infection control team (ICT) comprises an Infection Control Doctor (usually a medical microbiologist), one or more infection control nurses and clerical support. They report to a multi-disciplinary Infection Control Committee who liaises with senior management.

The hospital infection control team works with the Hospital Infection Control Committee. A Hospital Infection Control Committee consists of the ICT (see above), hospital chief executive or senior director, CCDC/CHP, Occupational Health Consultant and others as needed.

Question 37

What are the aims of an Infection Control team?

Answer 37

Maintain an effective programme for the prevention of hospital-acquired infection
Containment of infections brought into the hospitals by patients, staff or visitors.

Question 38

What are the Roles and Responsibilities of an Infection Control Team?

Answer 38

To ensure the management of infection control programmes is undertaken by competent, qualified Infection Control nurses

Provision of ongoing education for all healthcare staff

Develop infection control policies and ensure accessible to all staff

Facilities and equipment are available to enable compliance with policies

Ensure all clinical staff have received appropriate training

Infection control audits

Surveillance.

Question 39

What is a local health protection team?

Answer 39

The local HPT takes a main role in community infection control. It works with all community organisations that provide care, healthcare or treatments outside hospital including nursing / residential homes, nurseries and schools.

The HPT advises and helps maintain good infection control practices in these community settings. This is achieved through the direct input of health protection practitioners (who provide most of the HPT infection control advice) and the CCDCs/CHPs (who are the main link between CCG infection control teams and hospital ICTs).

For example, a HPT may advise private nursing home staff about infection control principles, advise schools and nurseries on infection control principles in conjunction with the local authority, and review the infection control practices of tattoo parlours and beauticians.

Question 40

What legal powers do health protection teams have?

Answer 40

The Public Health Act 1984 and subsequent Health Protection Regulations 2010 give UK local authorities powers to enable restrictions or requirements to be imposed on people and in respect of things and/or premises to protect human health, provided strict criteria are met.

The powers are exercised either directly or indirectly through the ‘Proper officer’, an officer appointed by (or employed by PHE to whom the duty is delegated) the local authority for a specific purpose.

The Proper Officer is usually the Consultant in Communicable Disease Control (CCDC)/ Consultant in Health Protection (CHP). These include:
Local authority powers
The 2A Orders
Other powers - E.g. Powers of entry or inspection to carry out health protection functions.

Question 41

What are “Local authority powers” in the context of infection control?

Answer 41

Local authority powers provide a range of measures that can be to used to prevent, protect against, control or provide a health protection response to an incident or spread of infection or contamination that presents, or could prevent, significant harm to human health.

They can be exercised without applying to a Justice of the Peace but specific criteria must be satisfied. The powers include:
Require that a child is kept away from school
Require a teacher to provide a list of contact details of pupils attending their school
Disinfect/decontaminate articles on request
Request (but not require) individuals or groups to cooperate for health protection purposes.
Restrict contact with, or relocate, a dead body for health protection purposes.

Question 42

What are “Part 2A Orders” in the context of infection control?

Answer 42

Part 2A Orders are obtained by local authorities on application to a Justice of the Peace and impose restrictions or requirements on a person, thing, body or human remains, or premises.

For example, for a person to be detained in a hospital; to restrict a person’s movements or contact with other people; or to require that a premises is closed or decontaminated.

The power also includes a requirement for a person to give information about a ‘related party, person, or thing’, as relevant to the case.

Question 43

Which general principles must be met before any local authority powers or part 2A orders can be enacted?

Answer 43

A person, thing, dead body or premises is, or may be, infected or contaminated

A risk assessment that the threat must present, or could present significant harm to human health

There is a risk of spread of contamination/infection

Use of the power is necessary to reduce that risk

The action is proportionate to reduce that risk

Use of the power is only to reduce that risk

Use of a Part 2A Order is for a specified time period.

*Note there are specific criteria for certain local authority powers and 2A orders and a 2A order cannot be used to impose medical treatment or vaccination on an individual.

Question 44

What legal powers do local authorities have in relation to enivormental health porection hazards?

Answer 44

The Environment Agency and Local Authority Environmental Health Departments:
Have legal powers to control (by giving permits to operate under certain conditions or enforcement notices) aspects of the environment that could be a threat to human health. Whether the EA or local environmental health departments are the regulator depends on the nature and size of the facility/establishment. These often include:
* Waste operations (including mining waste and waste incineration plants)
* Radioactive substances activity
* Water discharge and groundwater activities (including sewage disposal).

The local authiority generally:
Food Safety Act - Supplies and suppliers of food
Private water supplies
Statutory Nuisances and Clear Air section of the Environmental Protection Act 1990 - Pest control and other ‘nuisances’ e.g. fumes, smells, smoke, noise.
The Health and Safety at Work Act - Occupational setting to compel premises occupiers to clean and disinfect

Question 45

What is the Food Safety Act 1990?

Answer 45

A framework for regulations that govern:

Activity of food businesses
Composition and labelling of foods
Chemical safety
Food hygiene

Enforcement is the responsibility of local authority environmental health officers at a local level, and the Food Standards Agency nationally.

Question 46

What is the Statutory Notification of Infectious Diseases (NOIDS)?

Answer 46

There are statutory duties for reporting notifiable diseases in the Public Health Act 1984 and the updated Health Protection (Notification) Regulations 2010.

Registered medical practitioners in England and Wales have a statutory duty to notify the ‘proper officer’ of their local authority or local Health Protection Team of suspected cases of certain infectious diseases. In practice, this tends to be a CCDC/CHP within the local HPT.

Practitioners are asked to notify of any suspected or confirmed cases within 3 days, or to report orally by telephone if urgent. Diagnostic laboratories in England can notify by electronic means.

PHE collects these notifications and publishes analyses of local and national trends every week.

The Health Protection Regulations 2010 extended the duty of practioners to a new ‘all hazards approach’, where any haxard that could pose a public health threat must be notified.

Question 47

What are the notifiable diseases in the UK?

Answer 47

Acute encephalitis
Acute infectious hepatitis
Acute meningitis
Acute poliomyelitis
Anthrax
Botulism
Brucellosis
Cholera
Covid-19
Diphtheria
Enteric fever (typhoid or paratyphoid fever)
Food poisoning
Haemolytic uraemic syndrome (HUS)
Infectious bloody diarrhoea
Invasive group A streptococcal disease
Legionnaires’ disease
Leprosy
Malaria
Measles
Meningococcal septicaemia
Mumps
Plague
Rabies
Rubella
Severe Acute Respiratory Syndrome (SARS)
Scarlet fever
Smallpox
Tetanus
Tuberculosis
Typhus
Viral haemorrhagic fever (VHF)
Whooping cough
Yellow fever

Other diseases and contamination that may present significant risk to human health under the category ‘other significant disease’ e.g. Middle Eastern Respiratory Syndrome (MERS), radioactive agent release due to terrorism.

Question 48

What are the steps in a health protection teams response to an infectious disease?

Answer 48

1) What investigations (microbiological / environmental / epidemiological) are needed to identify the agent, the cause of the incident?

2) What is the Source of Infection?
* Is it a continuing source that may need to be controlled?
* If so, what generic control measures can be applied to limit morbidity whilst awaiting confirmation e.g. enhanced hand washing, environmental cleaning, etc?
* Are there others exposed who may need advice / treatment?

3) What is the likelihood of transmission?
* Advice / prophylaxis to close contacts, e.g. hepatitis B immunisation
* Occupational transmission, e.g. exclusion of food handlers with gastrointestinal infection

4) Is public health action necessary, done through a risk assessment:
* How infectious is the source
* How close is the contact
* How susceptible are those exposed
* Is the index case at risk of a poor outcome?
* Is the index case likely to pass the infection to others?
* Is there likely to be an ongoing source that needs controlling?
* Do contacts and others exposed to the same source need to be traced?
* Do the public need information or reassurance?

5. Is immediate public health action needed?
   * Seriousness of disease
   * Transmissibility of infection
   * Length of incubation period
   * Vulnerability of people exposed
   * Public/ media / political reaction
   * What is good practice
6. Possible interventions
   * Improve outcome for cases, e.g. antibiotics, immunoglobulin
   * Trace others exposed to source or cases to provide advice, antibiotics or vaccines
   * Prevent others being exposed to cases / contacts by rendering them non-infectious by use of antibiotics and / or isolation
   * Provision of hygiene advice
   * Exclusion from work / school
   * Closure of premises associated with incident e.g. cooling towers, food premises
   * Identify possible source and implement and monitor control measures to contain this source
7. Communication
   * Cases / contacts / clinicians
   * Internal - specialist advice within HPT / microbiology
   * External - local authorities, press e.g. outbreak of meningococcal disease in a school

Question 49

What are the aims of immunisation?

Answer 49

To provoke immunological memory to protect the individual against a particular disease.

Question 50

What are the types of immunisation?

Answer 50

Passive: Immediate protection with a temporary source of antibody, e.g. Immunoglobulin (Ig’s) and antitoxins

Active: Longer-term protection leading to the formation of antibodies

Question 51

What are the types of vaccines and give examples of each?

Answer 51

Live attenuated vaccine (weakened strains that replicate in the host):
Examples include: MMR, oral polio, BCG, Yellow Fever, Live attenuated Influenza (LAIV) and Herpes Zoster vaccine.

Inactivated vaccines (suspensions of whole intact killed organisms OR components of organism important in protection):
Examples include: Diphtheria Tetanus Pertussis (DTP), typhoid, Hepatitis B, flu, rabies, meningitis (ACWY, B) Hib, HPV

Question 52

What does attenuated mean?

Answer 52

Weakened

Question 53

What are the advantages and disadvantages of each type of vaccine?

Answer 53

Live attenuated:
Single dose often sufficient to induce long-lasting immunity
Long duration of immunity
Less stable: may revert to a virulent strain
Can cause disease in immuno-suppressed

Inactivated vaccine:
Stable
Unable to cause the infection
Need multiple doses and booster
Shorter lasting immunity

Question 54

What are the contraindications to vaccination?

Answer 54

A confirmed anaphylactic reaction to a previous dose of the vaccine or to a component of the vaccine

Immuno-suppression (no live vaccines)

Question 55

In what ways can a vaccine fail?

Answer 55

Primary: individual fails to make an adequate immune response to initial vaccination

Secondary: Individual makes an initial adequate response, but then immunity wanes over time

Question 56

What must be established before setting up a vaccine programme?

Answer 56

Is there a need for the programme:
Disease incidence
Disease severity
Mortality
Disease complications

Disease characteristics:
Distribution of disease e.g. Age, sex
Disease trends

Vaccine delivery:
Vaccine Efficacy and side effects
Availability and validity of delivering
Provision of trained primary care providers
Vaccine type

Other:
Population / cultural attitudes
Cost and benefit
Political expenditure

Question 57

What are the aims of a vaccination programme?

Answer 57

To protect those at the highest risk (selective immunisation strategy)

OR

To eradicate, eliminate or contain disease (mass immunisation strategy)

Question 58

What are the types of vaccine strategy that can be used?

Answer 58

Selective Vaccination:
Given to those at increased risk, for example:
For travel, e.g. Japanese B encephalitis
Occupation, e.g. Hepatitis B
High-risk groups e.g. Hepatitis B vaccine for neonates born to Hepatitis B positive mothers
Chronic disease, e.g. Pneumococcal following Splenectomy
During an outbreak, e.g. Hepatitis A

Mass Vaccination:
Given to everyone with the aim of:
Eradication - Disease and its causal agent have been removed worldwide, e.g. smallpox
Elimination - Disease has disappeared from one WHO region but remains elsewhere, e.g. polio
Containment - The point at which the disease no longer constitutes a ‘significant public health problem’, e.g. Hib

Question 59

What needs to be considered during vaccine policy design?

Answer 59

Aim of programme
Cost of programme
Population accessibility
Cultural attitudes and practices
Facilities available for delivery

Question 60

What are the steps in implementing a vaccine programme?

Answer 60

Pre-license:
Phase 1 studies = Safety studies - In healthy adults
Phase 2 studies = Immunogenicity (how effective is it at developing immunity) - In target population (n=100-120)
Phase 3 studies = Protective efficacy - In target population (large). Also cost-benefit analysis studies

Post-license:
Phase 4 studies = Surveillance - To detect adverse events

Question 61

Who decides if a new vaccine programme is implemented?

Answer 61

Recommendations for use of a vaccine/vaccine policy are based upon The Joint Committee of Vaccination and Immunisation (JCVI) expert opinion after reviewing all the available evidence.

The JCVI is an independent expert advisory committee whose role is to advise UK public health departments on matters relating to communicable diseases, preventable and potentially preventable through immunisation.

They are involved in:
Choice of policy - mass or selective
Publishing recommendations on ‘Immunisation against infectious disease’ (the green book)
License vaccine and batch release
Procurement of vaccine

Question 62

What factors are associated with poor vaccine uptake?

Answer 62

Socio-demographic variables
Deprivation
Urban living
Mobile families
Birth order
Large families
Children with chronic illnesses
Ethnicity

Personal variables
Parents
Professionals

Health service variables:
Poor coordination (private and public sectors)
Unclear responses
Access to guidelines and policies

Question 63

Give an example of a UK initiative that increased vaccine uptake.

Answer 63

1986: District immunisation coordinator appointed
1987: Rapid monitoring and feedback of coverage data - COVER statistics
1988: National guidelines on immunisation
1990: Accelerated immunity schedule
1990: GP contracts - financial incentives
1992: Parent-held records/Personal Child Health Record often referred to as the Red book

Others:
National vaccination campaigns - intermittent (e.g. MMR/Hib)
Opportunistic delivery
Specific immunisation clinics
Targeted information campaigns
Child Health Information Services (CHIS) computer generates automatic letters inviting children for vaccination, and ensures GP call and recall for immunisation

Question 64

What are COVER statistics?

Answer 64

In the UK since 1988 computerised child health records contain vaccination details of all children resident in the area. These are completed each time a vaccine is given by a healthcare professional and allow rapid monitoring and feedback of vaccine coverage data.

This information is collected every 3 months from local Child Health Computer Systems detailing the number of children who have completed the vaccination schedule at 1, 2 and 5 years of age.

Question 65

What are the uses of COVER statistics?

Answer 65

Detect change rapidly and monitor trends in uptake
Look for pockets of poor coverage
Estimate vaccine efficacy
Measure impact and success of a vaccination campaign
Evaluation of Vaccine Programmes
Disease incidence
Susceptibility
Vaccine Coverage
Adverse events and vaccine safety

Question 66

How is vaccine safety monitored?

Answer 66

The Committee on Safety of Medicines (CSM) advises the Medicines and Healthcare Products Regulatory Agency (MHRA) on the safety, quality and efficacy of vaccines

MHRA is responsible for the Yellow Card Adverse Drug Reaction reporting system

Yellow Card reports can signal the possibility that a product may be associated with certain risks. These can then be investigated further to decide whether a side effect is truly from a vaccine or not.

Question 67

What is the UK childhood vaccine schedule?

Answer 67

Question 68

What are the extra vaccines that are offered in the UK to at-risk children?

Answer 68

Question 69

What are the steps in managing a disease outbreak?

Answer 69

1) Confirmation of Outbreak
2) Verify the Diagnosis
3) Case Definition
4) Case Finding
5) Descriptive Epidemiology
6) Generate a Hypothesis
7) Analytical Epidemiology
8) Evaluate Control Measures
9) Surveillance

Question 70

What is an outbreak control team?

Answer 70

If an outbreak is suspected an Outbreak Control Team (OCT) should be convened to conduct the investigation with the following represented in the membership:

Essential:
* Consultant in Communicable Disease Control (CCDC)/Consultant in Health Protection (CHP)
* Environmental Health Officer (EHO)
* Consultant Microbiologist or Virologist
* Secretarial/Administrative support

Optional:
* Regional epidemiologist
* Media/press officer
* Infection control nurse
* State veterinary service
* Food chemist/microbiologist/Food Standards Authority
* Toxicologist
* Director of Public Health
* Water company

Question 71

How do you confirm an outbreak (step 1 of outbreak control)

Answer 71

Is there an increase in the number of cases expected in the population/time/place?

Confirm numbers; interview cases, review laboratory findings

Is further investigation needed? The extent and urgency of the investigation should be considered.

Question 72

How do you verify the first cases diagnosis during outbreak management (step 2)

Answer 72

Obtain medical records and laboratory reports

Repeat tests if necessary

Further clinical testing if needed

Question 73

How do you set a good case definition in outbreak management (step 3)

Answer 73

Component of case definition
(Example) Hepatitis A Outbreak

Person
Detail needed - Type of illness (e.g. “a person with…”)
Example - A person with an acute illness

Place
Detail needed - Location of suspected exposure
Example - Which occurred after staying at Hotel X

Time
Detail needed - Based on incubation (if known)
Example - Between Sep-Nov 2015

Clinical symptoms/Lab results
Example - with jaundice or elevated liver function tests

Define population at risk
Example - Of all residents and diners during this period.’

Question 74

How do you do case finding during disease outbreaks (step 4)?

Answer 74

Interview known cases

Locate others exposed to probable risk factor

Review routine surveillance data, notifications and laboratory results

Contact other CCDC’s/CHPs, EHO’s, health workers

Question 75

What is descriptive epidemiology during outbreak management (step 5)?

Answer 75

Using data collected by the outbreak control team and arranging it into a set of descriptive data (e.g. person/place/time).

This can also be used to form an Epidemic Curve or Line list.

Question 76

What is an epidemic curve and what are its uses?

Answer 76

A graph of occurrences of cases over time, this can help determine the nature of the outbreak:
Point (common) source
Propagated (continuing) source
Point source and person-to-person spread

Question 77

What is a line list?

Answer 77

A table summarising the information about persons associated with the outbreak.

Each row represents a single individual and each column represents a specific characteristic:
Identifying information
Demographics
Dates of illness/results
Pertinent risk factors
Exposures
Clinical details/lab results

Question 78

Why is it important to generate a hypothesis during disease outbreak management (step 6)?

Answer 78

Causes may have already been suspected, however, a formal hypothesis is helpful to establish after reflecting on the data interpreted in the descriptive epidemiology. It is useful for determining the most likely exposure that has caused the outbreak.

Question 79

What is the role of analytical epidemiology in disease outbreak management (step 7), and what types of studies are normally used?

Answer 79

Epidemiologic analytical studies can be used to test your generated hypothesis. If controls are chosen appropriately this will reduce the bias in the studies performed.

This is often done through a cohort or case-control study:

Cohort Study
Everyone potentially exposed
Only use if a comprehensive list is available
Can assess relative risk and attack rate (the proportion of an at-risk population that contracts the disease during a specified time interval.)

Case-Control Study
Comparison of exposure amongst cases and controls.
Useful study if the complete list is unavailable or is too large
Can assess the odds ratio

Question 80

How do you evaluate your control measures in disease outbreak management (step 8)?

Answer 80

Monitor the incidence of cases once control measures are enforced.

Laboratory results useful for continued definitive identification of infectious agent in cases and if appropriate monitoring response to treatment/control measures.

Question 81

What types of control measures may be used during disease outbreak management?

Answer 81

Control source (Animal/Human/Environmental)
Consider closing outlet
Isolate and/or treat cases
Destroy/treat food
EHO to take samples if necessary

Protect persons at risk
Consider prophylaxis (e.g. antibiotics)
Improve hygiene / personal protective equipment if applicable

Interrupting transmission
Depends on the mode of spread (e.g. bottled water if contaminated water supply with Cryptosporidium).

Question 82

What are the steps to good communication during an outbreak management situation?

Answer 82

During outbreak
Agree media strategy at initial OCT meeting and review at every meeting

After outbreak
Outbreak report published and disseminated
Recommendations made

Media Strategy
Ensure accurate and timely information relayed
Consider which type of media and for which groups; social media/secure comms/sensitive information/anonymity of cases.
Media attention may be necessary if public action is required.

Question 83

What are the different types of sources of an outbreak?

Answer 83

Point source - explosive (primary cases will cluster within the range of the incubation period) e.g. Salmonella outbreak at wedding reception

Continuing source - e.g cases of S. agona PT15 by week of onset in England and Wales

Point source and person-to-person spread - e.g. E.Coli 0157 in a residential home

Question 84

What type of source does this epidemic curve show?

Answer 84

Point source

Question 85

What type of source does this epidemic curve show?

Answer 85

Continuing source

Question 86

What type of source does this epidemic curve show?

Answer 86

Point source and person-to-person spread

Question 87

What are the specific considerations when managing an outbreak of Food/waterborne gastro-enteritis?

Answer 87

General:
Involve Environmental Health Officer in the investigation to find the source.
Collect stool specimens if possible from all sporadic cases; as many as possible in the outbreak

Prevention:
Hand washing and no towel sharing
Disposal of soiled material
Disinfect toilet area and taps daily
Education of personal hygiene and hygiene in the preparation of food

Exclusions:
All cases must be excluded from work or school until free from diarrhoea and vomiting for 48 hours as a minimum.
In the case of an ‘at risk’ group, exclude for longer and consider the need for microbiological clearance before returning to work in:
* Food handlers
* Health care facilities
* Children under five years
* People with learning disabilities

Screening and follow up:
In the case of ‘non-risk’ groups, there is no microbiology follow up
Most food poisoning - no screening of contacts necessary, except in the case of Typhoid and E.coli OI57

Question 88

What are the specific considerations when managing an outbreak of Food/waterborne gastro-enteritis?

Answer 88

Check:
Occupational exposure
Recreational exposure
Domestic exposure
Consumption of water, vegetables, fish (in areas of infected water)

Question 89

Which survielance systmes are in place to monitor internaitonal disease outbreaks?

Answer 89

Formal reports are received from Ministries of health, WHO Regional and Country offices, national public health organisations, military and civilian laboratories, academic institutions, WHO collaborating centres and non-governmental organisations (NGO’s).

Informal sources such as social media and online news reports are monitored by the Global Public Health Intelligence Network (GPHIN) to identify information about outbreaks of disease or public health events of international concern.

This was used in covid-19 and ebola outbreaks.

Question 90

What is the difference between an incident, a major incident, an emergency and a disaster (in relation to emergency and incident planning purposes)?

Answer 90

An incident is an event requiring a response from the emergency services.

An emergency is an event or situation that threatens serious damage to human welfare or the environment or war or an act of terrorism that threatens serious damage to security.

A major incident is an event or situation requiring a response under one or more of the emergency services’ major incident plans.

A disaster is a serious disruption of the functioning of a community or a society involving widespread human, material, economic or environmental losses and impacts, which exceed the ability of the affected community or society to cope using its own resources.

Question 91

What are the different ways of categorising emergencies?

Answer 91

Source:
‘Man-made’ e.g. transport-related, terrorism
Natural e.g. flooding, earthquake

Speed:
‘Big bang’ - sudden events such as bombings or earthquakes
Rising tide’ gradual events such as famine, and infectious disease pandemics.

Question 92

What is emergency planning?

Answer 92

The aspect of emergency management concerned with developing and maintaining procedures to prevent emergencies and to mitigate the impact when they occur.

It is a systematic and ongoing/cyclical process which should evolve as lessons are learnt and circumstances change.

Question 93

What is emergency preparedness?

Answer 93

The step beyond emergency planning, where a plan is in place, and has been tested: organisations and individuals are clear about their roles and responsibilities.

Question 94

What factors decide if an emergency becomes a disaster?

Answer 94

The level of exposure to a hazard
The conditions of vulnerability that are present
The capacity or measures to reduce or cope with the potential negative consequences
Level of community resilience

Question 95

What are the different types of responses to an emergency?

Answer 95

Category 1: Core to civil protection
Emergency services, local government, acute hospitals and emergency departments, health service managers, public health agency, the environment agency, maritime and coastguard agency, port health authority

Category 2: Play a supporting role
Utility companies, highway authorities, railway, harbour and airport operators, health and safety executive, primary care organisations

The military are not categorised here because the Act governs responses to civil emergencies

Question 96

What are the legal responsibilities of category 1 and 2 responders?

Answer 96

Category 1 responders have to put in place emergency plans, business continuity arrangements, arrangements to keep the public informed during emergencies, and to provide advice and assistance to local business and voluntary agencies about business continuity.

Category 1 & 2 responders have a duty to cooperate and share information for the purpose of civil protection.

Question 97

What steps can be taken before an emergency to increase preparedness?

Answer 97

Build resilience:
Set up/improve surveillance and forecasting systems
Advocacy for political commitment
Business continuity management plans (which appraise potential organisational risks, threats and vulnerabilities and proactively plans to mitigate their effects)

Plan an effective response:
Develop a risk profile to determine which potential emergencies you should prioritise
Plan how to minimise the impact of the emergency:
* What immediate actions can be taken, e.g. how will you know an event is an emergency (different services have usually defined situations that constitute an emergency or major incident), and how will you be alerted?
* What remedial actions can then be taken to reduce the effects?
* What is the recovery plan following these actions?
Prioritise 3 groups in the plans: the vulnerable, the victims and the responders.
Define roles and responsibilities of partners in an emergency.
Train responders
Maintain plans – they must be kept up to date.
Establish lines of communication to other agencies and the public
Multi-agency planning exercises and drills to test protocols

Question 98

What is the management structure of an emergency in the UK?

Answer 98

The management of an emergency will involve one or more of 3 levels of coordination, command and control for emergency incidents:
* Bronze (operational): on-scene responders
* Silver (tactical): near to scene directing response and allocating resources
* Gold (strategic): off-site e.g. at headquarters coordinating multi-agency response. Attended by senior representatives from responding agencies; they must be able to commit to decisions and expenditure.
* The Cabinet Office Briefing Rooms (COBR): For when there are more than one emergency response over several regions, offers a level of strategic oversight in the UK.

A ‘bottom up’ approach (bronze upwards) is taken, as not all emergencies will require multi-agency strategic or on scene tactical coordination.

The Gold command is supported by a team providing health advice - Scientific and Technical Advisory Cell (STAC) in the UK. It is chaired by a senior public health consultant, e.g. Director of Public Health, or Consultant in Communicable Disease Control/Consultant in Health Protection. There should be multi-agency representation from the health services/commissioners.

Decisions should be taken at the lowest appropriate level, with co-ordination at the highest necessary level, i.e. response should be as local as possible, with higher level of response only if necessary for resources or coordination

Question 99

What is the role of the Cabinet Office Briefing Rooms (COBR) and how are they organised?

Answer 99

Play a role when there is more than one emergency response over several regions, offers a level of strategic oversight in the UK.

They take the strategic lead and is a forum of Ministers and senior officials from relevant Departments and agencies, brought together to make decisions on an emergency response.

External representatives and experts are invited to attend COBR meetings as appropriate; discussions are confidential.

COBR should facilitate rapid coordination of the Central Government response and effective decision-making.

In an emergency where a central response is required, a Lead Government Department (LGD) is appointed. The LGD is responsible for ensuring that appropriate plans exist to manage the emergency, for ensuring that adequate resources are available and for leading on public and parliamentary handling. LGDs are also responsible for ensuring they have effective arrangements to access scientific and technical advice in a timely fashion in an emergency. This may involve establishing a Science Advisory Group for Emergencies (SAGE).

Question 100

What steps should be taken when managing a an emergency or disaster?

Answer 100

Gather information (METHANE):
M – Major Incident Declared?
E – Exact Location
T – Type of Incident
H – Hazards present or suspected
A – Access – routes that are safe to use
N – Number, type and severity of casualties
E – Emergency services present, and those required

Assess risk to health:
* Review health effects and exposure pathways (obtain expert clinical/toxicological advice, weather modelling of plume)
* Define affected population
* Consider sampling persons, animals, environment
* Establish register of exposed/symptomatic persons.

Response:
* Biological, chemical, or radiation release hazard: hazard containment, decontamination then primary treatment of victims, countermeasures, follow up
* Infectious epidemic: containment by case detection and isolation and contact tracing, control measures, prophylaxis for exposed, arrange definitive treatment of cases, follow up.

Communications:
* Advise partner agencies and professionals via a STAC
* Media (statement/press release/briefings)
* Public (telephone helpline)

Post acute-phase response – Activate recovery plans:
* Site clean up
* Clinical follow up of those affected
* Initiate epidemiological study

Question 101

What steps should be taken after an emergency situaiton?

Answer 101

Long-term follow up/surveillance of cases/exposed and analytic study

Lessons learnt:
* Written report
* Audit of response
* Review and revision of plans

Question 102

What is the role of the Scientific and Technical Advisory Cell (STAC) during an emergency repsonse?

Answer 102

Provide understandable scientific and technical advice during the response to the emergency
Advise on impact on health of the population, and health impact of containment or evacuation policies
Agree all media statements and advice to the public related to health with the Gold command chair
Liaise with national departments of (public) health, other national and local agencies
Formulate advice to health professionals, e.g. ambulance service, primary care
Formulates advice on strategic management of the health service response.

Question 103

What are port health authorities?

Answer 103

Port Health Authorities are Local Authority environmental health departments and have powers to control the public health aspects of port activity involving ships, international trains and aircraft. Each Port Health Authority appoints port health officers and port medical officers.

Question 104

What is the functions of Port Health Authorities?

Answer 104

1. Prevent the importation of disease, e.g. visit and inspect aircraft
2. Rodent control, e.g. ships must be inspected every 96 months for rats
3. Imported food, e.g. inspection and clearance of Products of Animal origin into the EU
4. Fish and shellfish, e.g. FSA monitor quality of local shellfish
5. Food premises inspections, e.g. monitors standards in shore-based premises and in-flight catering
6. Animal health, e.g. assist with enforcement of rabies controls.

Question 105

What is a Port Medical Officer?

Answer 105

May act as a Port Medical Inspector (PMI) providing advice to Immigration and Nationality service. Also involved in medical clearance (including Chest X-ray) in any person intending to remain in the UK for 6 months or more or those who are unwell.

Question 106

How does medical clearance arrivals to the UK?

Answer 106

Port Medical Inspector (PMI) gives medical clearance (including Chest X-ray) to any person intending to remain in the UK for 6 months or more or those who are unwell.

Medical clearance may take place in the country of origin

Persons with infectious diseases that are likely to endanger the health of others in the UK may be refused entry

Unless entry is refused, details of any immigrant and results of any examination are passed to CCDC in the proposed area of residence

Subsequent action can vary but include invitations to attend for further medical assessment

Question 107

What are the WHO’s international health regulations?

Answer 107

The International Health Regulations (IHR) are an agreement between 196 countries to work together for global health security. All countries are required to report events of international public health importance to the WHO with an aim to prevent, protect against, control and respond to the international spread of disease while avoiding unnecessary interference with international traffic and trade.

The IHR were enforced in 2007 outlining that all countries must have the capacity to do the following;
DETECT: Ensure surveillance systems and laboratories can identify potential threats.
ASSESS: Work alongside other countries in making decisions for public health emergencies.
REPORT: Report specific diseases and PHEICs (public health emergencies of international concern)
RESPOND: Respond to public health occurrences.

Question 108

What is a PHEIC?

Answer 108

Public health emergencies of international concern

A PHEIC should be declared to the WHO if 2 of 4 following criteria are met:
1. Is the public health impact of the event serious?
2. Is the event unusual or unexpected?
3. Is there a significant risk of international spread?
4. Is there a significant risk of international travel or trade restrictions?

Three PHEIC have been declared in recent years - H1N1 Influenza (2009), Polio (2014), Ebola (2014).

Question 109

Which diseases are notifiable to the WHO by the international health regulations?

Answer 109

Always notifiable:
Smallpox;
Poliomyelitis due to wild-type poliovirus;
SARS;
Human influenza caused by a new subtype.

Potentially notifiable:
Cholera
Plague
Yellow Fever
Viral haemorrhagic fever
West Nile Fever
Others included

Question 110

What is an outbreak?

Answer 110

A localised epidemic of two or more cases of disease related in time and or place in excess of normal expectancy.

Question 111

What are the objectives of an outbreak control team?

Answer 111

a. Identify source and mode of spread

b. Interrupt further transmission

c. Prevent secondary spread

d. Educate

e. Introduce future preventative measures

f. (prosecute)