immunisation and notifiable infectious diseases Flashcards
passive immunisation
- Protection provided from the transfer of antibodies from immune individuals
- Most commonly cross-placental transfer of antibodies from mother to child (e.g. measles, pertussis)
- Or, via transfusion of blood or blood products including immunoglobulin (e.g. Hep B)
- can also be injected
- Protection is temporary – usually only a few weeks or months.
- normal human immunoglobin (HNIG) derived from pooled plasma of donors
what is Human normal immunoglobulin (HNIG)?
- contains antibodies against common, currently prelevant infections in the population
- given to immunocomprimised children to protect against measels and hepA
- can also have specific antibodies amdinistered for tetnus, hepB, rabies and varicella zoster
whats the difference between active and passive protection?
passive - given donor antibodies
active - given antigen to promote an immune response to make own antibodies
what are vaccines made of?
- inactivated (killed) (e.g. pertussis, inactivated polio)
- attenuated live organisms (e.g. yellow fever, MMR, polio, BCG)
- secreted products (e.g. tetanus, diphtheria toxoids)
- the constituents of cell walls/subunits (e.g. Hep B) or
- recombinant components (experimental)
vaccine failure
No vaccine offers 100% protection
Small proportion of individuals get infected despite vaccination.
Primary vaccine failure – person doesn’t develop immunity from vaccine.
Secondary vaccine failure – initially responds but protection wanes over time.
what is the green book?
The Green Book has the latest information on vaccines and vaccination procedures, for vaccine preventable infectious diseases in the UK.
name some examples of vaccine preventable diseases.
- diptheria, pertussis, tetanus (DPT)
- polio
- haemophilus influenza type B
- meningococcal disease
- MMR
- pneumococcal disease
- human papillomavirus
- hepB
- varicella-zoster virus
contact tracing - meningitis.
Contact for meningitis is taken to be any person having close contact with a case in the past 7 days
Close contact includes kissing, sleeping with, spending the night together or spending in excess of eight hours in the same room
notifiable diseases.
- Diseases, infections and conditions specifically listed as notifiable under the Public Health (Control of Disease) Act 1984and theHealth Protection (Notification) Regulations 2010
- Legal obligation for any doctor that suspects a case to report on clinical suspicion.
name the notifiable diseases.
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
Monkeypox
Mumps
Plague
Rabies
Rubella
Severe Acute Respiratory Syndrome (SARS)
Smallpox
Tetanus
Tuberculosis
Typhus
Viral haemorrhagic fever (VHF)
Whooping cough
Yellow fever
outline the role of surveilance.
Detection of any changes in a disease
Outbreak detection
Early warning
Forecasting
Track changes in disease
Extent and severity of disease
Risk factors
Allows development of interventions targeted at vulnerable groups
what measures do we take to protect the community after an outbreak or report of notifiable disease?
Investigate: contact tracing, partner notification, lookback exercises, etc…
Identify and protect vulnerable persons: e.g. chemoprophylaxis, immunisation, isolation
Exclude high risk persons or from high risk settings
Educate, inform, raise awareness, health promotion
Coordinate multi-agency responses
how much of the population need o be immune for herd immunity to be reached?
this depends of the R number for the specific disease
- for mumps 80% of the population (because the R number is 5)
outline the different types of vaccine eg live-attenuated.
- Inactivated vaccines,
- live-attenuated
- messenger RNA (mRNA) vaccines,
- subunit, recombinant, polysaccharide, and conjugate vaccines,
- toxoid vaccines
- Viral vector vaccines.
Inactivated Vaccines
Definition: Made from pathogens that have been killed or inactivated so they cannot cause disease.
Examples:
Inactivated poliovirus vaccine (IPV).
Hepatitis A vaccine.
Rabies vaccine.
Advantages:
Safe for immunocompromised individuals as they cannot replicate.
Limitations:
Often require multiple doses (boosters) to maintain immunity.
Live-Attenuated Vaccines
Definition: Contain weakened forms of the live pathogen that can replicate but not cause severe disease.
Examples:
Measles, Mumps, and Rubella (MMR) vaccine.
Varicella (chickenpox) vaccine.
Yellow fever vaccine.
Oral polio vaccine (OPV).
Advantages:
Induce strong, long-lasting immunity (similar to natural infection).
Often effective with fewer doses.
Limitations:
Risk of causing disease in immunocompromised individuals.
Require careful storage (cold chain).
Messenger RNA (mRNA) Vaccines
Definition: Use synthetic mRNA that instructs cells to produce a harmless piece of the pathogen (e.g., a viral protein), triggering an immune response.
Examples:
Pfizer-BioNTech COVID-19 vaccine.
Moderna COVID-19 vaccine.
Advantages:
Rapid development and production.
Non-infectious and cannot integrate into the host genome.
Limitations:
Require ultra-cold storage for stability.
Subunit, Recombinant, Polysaccharide, and Conjugate Vaccines
a) Subunit Vaccines
Definition: Use specific parts (antigens) of the pathogen, such as proteins or sugars.
Examples:
Hepatitis B vaccine.
Human papillomavirus (HPV) vaccine.
Advantages:
Safe, as they do not use live components of the pathogen.
Limitations:
May require adjuvants and booster doses to enhance immune response.
b) Recombinant Vaccines
Definition: Antigens are produced using recombinant DNA technology.
Examples:
Recombinant zoster vaccine (Shingrix).
Advantages:
High specificity, minimizing the risk of adverse reactions.
c) Polysaccharide Vaccines
Definition: Contain long chains of sugar molecules that resemble those on the surface of the pathogen.
Examples:
Pneumococcal polysaccharide vaccine (PPSV23).
Limitations:
Poor immune response in children under 2 years.
d) Conjugate Vaccines
Definition: Combine polysaccharides with a protein to improve immune response, especially in young children.
Examples:
Haemophilus influenzae type b (Hib) vaccine.
Pneumococcal conjugate vaccine (PCV13).
Advantages:
Effective in young children.
Toxoid Vaccines
Definition: Use inactivated toxins produced by bacteria to elicit immunity against the toxins.
Examples:
Diphtheria vaccine.
Tetanus vaccine.
Advantages:
Protect against diseases caused by bacterial toxins.
Limitations:
Require boosters for long-lasting immunity.
Viral Vector Vaccines
Definition: Use a modified virus (vector) to deliver genetic material encoding an antigen from the pathogen.
Examples:
Johnson & Johnson COVID-19 vaccine.
AstraZeneca COVID-19 vaccine.
Ebola vaccine.
Advantages:
Strong immune response.
Can be used for multiple pathogens by changing the genetic payload.
Limitations:
Pre-existing immunity to the vector may reduce effectiveness.
DOT (not this topic lol, TB)
directly observed therapy
- because obvs tb treatment is so long
- a healthcare worker or someone observes them taking their medication each day
