U.S Health final exam- infectious disease Flashcards
wearing long sleeves can break the chain of infection at
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Port of entry
a mosquito cannot get in
Ten Greatest Pubic Health Achievements
Ten Great Public Health Achievements — Worldwide, 2001-2010
Reductions in Child Mortality
Vaccine-Preventable Diseases
Access to Safe Water and Sanitation
Malaria Prevention and Control
Prevention and Control of HIV/AIDS
Tuberculosis Control
Control of Neglected Tropical Diseases
Tobacco Control
Increased Awareness and Response for Improving Global Road Safety
Improved Preparedness and Response to Global Health Threats
Ten Great Public Health Achievements – United States, 2001-2010
Vaccine-Preventable Diseases
Prevention and Control of Infectious Diseases
Tobacco Control
Maternal and Infant Health
Motor Vehicle Safety
Cardiovascular Disease Prevention
Occupational Safety
Cancer Prevention
Childhood Lead Poisoning Prevention
Public Health Preparedness and Response
Deadly infectious diseases
how has infectious disease impacted people
what are some examples of outbreaks
Throughout time many infectious diseases have killed millions of people
Bubonic plague (“Black Death”)-1/3 of European population
Small Pox- has been eradicated
Cholera
Tuberculosis (TB)
Typhoid
Yellow fever
Public Health measures
Purification of water
Proper disposal of sewage
Pasteurization of milk
Immunizations
Improved nutrition
Personal Hygiene
Discovery of antibiotics
Infectious Agents
Bacteria:
Tuberculosis, cholera, typhoid, tetanus, diphtheria, dysentery, syphilis, streptococci, staphylococci
Viruses:
Smallpox, poliomyelitis, hepatitis, measles, rabies, AIDS, yellow fever
Parasites:
Malaria, cryptosporidiosis, giardiasis, roundworms,
, hookworms, pinworms
Diseases caused by viruses
Smallpox
Yellow fever
Polio
Hepatitis
Influenza
AIDS
Common cold
Measles
Diseases caused by protozoa
Malaria
Cryptosporidiosis
Giardiasis
Pinworm
Tapeworm
Hookworm
Roundworm
How can infectious diseases be transmitted?
Person-to-person
Via respiratory secretions
Sexually transmitted
Water
Fecal-oral route
Food
Vectors
Mosquitoes, rats, bats
Fomites- touching contaminated objects and putting hands to face, nose or eyes
Chain of Infection Links
link 1
Link 1- Pathogen: Bacteria, virus, parasite that cause illness in humans
Chain of Infection Links
link 2
Link 2: Reservoir: this is the place where the pathogen can live and multiply.
Chain of Infection Links
link 3
Link 3: Method of transmission: this is the way a pathogen can travel from one host to another
Chain of Infection Links
link 4
Link 4: Susceptible host: One that can be readily infected.
- Not all hosts are susceptible-they have immunity to the pathogen
- The support of the pathogen’s life and its reproduction depends on the degree of the host’s resistance
Port of exit:
how can an infectious microorganism leave the body
How an infectious microorganism may leave the body
- Secretions of mucus
- Blood
- saliva
- Other fluids
Port of entry
what is ths
what are the 4 methods of entry
: The route through which the pathogen enters a new host
4 methods of entry:
Respiratory system (inhalation)
Gastrointestinal (ingestion of pathogen)
Urinary and reproductive tracts (sexual contact)
Breaks in protective skin barrier
How to interrupt the chain of infection:
what is link 1 and how can it be interrupted
The most vulnerable part of the chain is the point where public health measures can interrupt to prevent the spread of disease!
Pathogen identification
- Proper identification of infectious agent and appropriate treatment
- Correct antibiotic for treatment of infectious disease
How to interrupt the chain of infection:
Eliminate the reservoir
how can we prevent the spread of food-borne pathogens
what can prevent water-borne pathogens
what two things are necessary
By maintaining proper hygiene you can prevent spread of food-borne pathogens
Having adequate water and sewage treatment can prevent spread of water-borne pathogens
Disinfection and sanitation
How to interrupt the chain of infection:
Prevent means of transmission
Direct or indirect contact can be altered by:
- Proper hand washing
- Isolation of those infected (quarantine/isolation)
- Use of condoms
- Not working when contagious
- Wearing masks
How to interrupt the chain of infection
Susceptible Host:
Resistance of host can be increased by immunization
Protect high-risk patients by wearing a mask with :
- Cancer patients
- AIDS
- Transplant patients
- Infant and elderly
- Proper disposal of needles/sharps
How to interrupt the chain of infection
Ports of entry
what can you wear
what should you cover
what should you wahs before eating
what else should you wear
Wear long sleeve shirts to prevent malaria carrying mosquito from biting (break protective skin barrier)
Cover open wounds
Wash hands before eating (avoid pathogen entering via GI system)
Wearing PPE
How to interrupt the chain of infection
Ports of exit
what should you always wash hands with
what else should you wear
what should you properly dispose of
what etiquette should you have
Hands: always wash hands with soap and water after handling potentially contaminated material
PPE such as gloves and masks if respiratory droplets are a concern
Proper trash and waste disposal
Respiratory etiquette
What are some ways to break the chain of infection for COVID-19?
Wearing a mask
Social distancing
Hand hygiene
Cover coughs & sneezes
Clean & disinfect
Monitor daily health
are these all transmission?
Public Health Measures
Epidemiological Surveillance:
what do PH officials always do and what will they do if necessary
what is contact tracing
what happens after contact tracing??
Epidemiological Surveillance:
- Public health officials watch for diseases. If necessary they will interrupt the chain of infections
- Contact tracing: Identification and diagnosis of persons who may have come into contact with an infected person.
When is contact tracing routinely used??
- Immunization and treatment of identified patients to prevent further spread
- Quarantine/isolation if necessary
Eradication
when is eradiation possible
what disease was eradicated
what disease is eradiacted from in the western hemisphere but where are there still cases
what disease has had recent outbreaks in the U.S
Eradication is possible if there is no non-human reservoir and if a vaccine exists
Smallpox was eradicated from the world
Polio has been eradicated in the Western Hemisphere- still see some wild cases particularly in Afghanistan, Pakistan (not eradicated), Syria (has had outbreaks in refugee camps)
Measles- in the US have had recent outbreaks
Rabies
what does it affect
what is the infectious agent
where is it found
how is it transmitted
what is the port of entry
Fatal disease of the nervous system
Infectious agent: Rabies virus
Is found in wild and domestic animals such as
- Dogs
- Raccoons
- Bats
Transmitted by the saliva of an infected animal
Port of entry: broken skin from bite or scratch
Rabies
How can we break the chain?
what can we do to cats and dogs
what campaigns can we have
what can be administered to wildlife
who should get pre-exposure immunization
Why not vaccinate everyone??
Rabies immunization for all cats and dogs - link 4 susceptible host
Educational campaigns
Oral administration of vaccine to wildlife
Pre-exposure immunization
- veterinarians, park rangers
Why not vaccinate everyone??
Smallpox
when was it eradicated
what was the mortality rate
what was the reservoir
how was it transmitted
how was it eradicated
Declared eradicated in 1979. The last known case was in 1978.
High mortality rate-30%
NO animal or environmental reservoir. Found only in humans
Transmitted by respiratory droplets or direct contact
Eradicated by “Ring Immunization”
Measles
what is it the leading cause of
what is the R0 and what does that tell you about the infectious rate of the disease
what is the pathogen
how is it transmitted
how can it be controlled
The leading cause of vaccine-preventable deaths in children worldwide
Highly infectious communicable disease-R naught (R0) of 18
Pathogen: measles virus
Transmitted to humans by respiratory droplets
How can this be controlled?
- Immunizations
- Isolation of those infected
rank the diseases on which is least to most contagious
mumps
hepatitis c
ebola
HIV
measles
SARS
Hepatitis C
ebola
HIV
SARS
Mumps
measles
ranked from most to least contagious
Polio
what is it the main symptom that is it Characterized by
what pathogen is it caused by
what was the goal for eradication
what Countries have never interrupted the transmission of wild polio:
what is the main method of control
Characterized by flaccid paralysis
Pathogen: poliovirus
World Health Organization set a goal for worldwide eradication for 2000
Countries that have never interrupted the transmission of wild polio:
- Afghanistan
- Pakistan
Method of control: immunization in early childhood
Immunizations
how does it effect diseases
what are the risks of it
Immunizations are the most effective intervention for preventing disease and promoting health
Immunizations do not come without risks
- Allergy to eggs
- Allergies to components of vaccine (neomycin, latex, thiomersal)
- Seizures
- Guillain-Barre syndrome
Fear of vaccines
what are people scared that it might cause
what do some vaccines come with and what do some parents refuse to accept
what is lost if many people do not get vaccine, what is once example
why are pharmaceutical companies reluctant to develop vaccines
Fear of autism (MMR) and SIDS (pertussis) from vaccines
Side effects do exist for some vaccines, Some parents refuse to accept risks
Herd immunity is lost if many people do not get vaccinated
- Measles outbreak example of losing herd immunity
Pharmaceutical companies are reluctant to develop vaccines
- Low profits
- Risk of law suits
Public health
what have measures been successful to do
Many public health measures have been successful in controlling disease but requires constant diligence
What do you think are some issues that may result due to budget cuts?
Dengue Fever
what is it and what are the 2 forms
what are the symptoms
what are the viruses that cause it
Dengue is an acute infectious disease that comes in two forms: dengue and dengue hemorrhagic fever.
The principal symptoms of dengue are high fever, severe headache, backache, joint pains, nausea and vomiting, eye pain, and rash. Generally, younger children have a milder illness than older children and adults.
Dengue and dengue hemorrhagic fever are caused by any one of four closely related flaviviruses, designated DEN-1, DEN–2, DEN-3, or DEN-4.
Dengue Fever
was it an endemic, pandemic, epidemic etc and where
how is it transmitted
what animals can serve as a reservoir
what was approved for this disease
Dengue is endemic in many tropical countries in Asia and Latin America, most countries in Africa, and much of the Caribbean, including Puerto Rico.
Dengue is transmitted to people by the bite of an Aedes mosquito that is infected with a dengue virus.
Monkeys may serve as a reservoir in some parts of Asia and Africa. Dengue cannot be spread directly from person to person. Susceptibility to dengue is universal. Residents of or visitors to tropical urban areas and other areas where dengue is endemic are at highest risk of becoming infected
A vaccine was recently approved in US, only for those with lab confirmed previous infection. The best preventive measure for residents living in areas infested with Aedes aegypti is to eliminate the places where the mosquito lays her eggs.
Dengue Fever Cain of Infection
Reservoirs:
Portals of exit:
Modes of transmission:
Portals of entry:
Factors in host susceptibility:
Reservoirs:
Portals of exit:
Modes of transmission:
Portals of entry:
Factors in host susceptibility:
What is One Health?
what is connected
what happens as the pop. grows
what makes people more vulnerable to disease
It means that animals, humans and environment health care connected
As the population grows, we interact with animals and the environment in new ways that increase the risk of becoming infected with new diseases
Poverty, war, limited access to healthcare make people vulnerable to disease
What are some ways that infectious diseases are spread?
how can it be spread through the globe
how can it be spread through food
what environment can spread pathogens quickly
where do these viruses persist
Global travel:
- New pathogens can be introduced via global air travel
- One example is the SARS outbreak of 2003
—-Jumped from animals at an urban market in China and spread widely via global air travel
- COVID-19 had a similar means of transmission
Industrial food production
- Farms are much bigger and more disruptive to natural ecosystems causing pathogens to spread quickly between wildlife, domestic animals and people
- Avian Influenza (H1N1 & H7N9)- These viruses persist in Asia and Africa as wild birds infect poultry and are in close contact with people
How can viruses spread to humans?
how often to viruses evolve and adapt to which host
who do humans have contact with the transmit diseases
what inssects most often carry disease
what makes people have high risk of infections
Viruses evolve much faster and adapt to humans quickly
Disturbing wildlife habitats, humans have much greater contact with animals that transmit viruses
Countries response to disease threats
Mosquitoes and ticks carrying virus into new habitats as seasons and climates change
Without clean water and food waste disposal and medical care people have higher risk of infections
Viral threat: HIV/AIDS
when was it first recognized
is there a cure
what are 2 ways of transmission
First recognized in the USA in 1981
There is no cure to date but many treatments to manage it
Transmission:
Sexual contact:
—Homosexual transmission is the most common in the US
—Heterosexual transmission is the most common around the world
Sharing of needles
- IV drug abusers at high risk
- Medical use of unsterile needles
Viral Threat: HIV/AIDS
how can it transmitted to child
what is screened and what is the result
Transmission
- Mother to infant
- Prenatal or during birth
- Breastfeeding
Blood transfusions
- We screen blood products in the US so not typically seen in the US but can occur globally if they do not screen blood products
How can we control transmission?
Education
Behavior modification
Treatment of drug users
Distribution of condoms
Clean syringes
Needle exchange programs
Abstinence
Other emerging viruses
what are the 5 viruses and where are the outbreaks
Measles- 1282 cases in US during 2019 (372 cases in all of 2018)
Ebola- Have had several outbreaks in west African countries in 2014-2016. Current outbreak in Democratic Republic of Congo (DRC)
Monkey pox- have had outbreaks in Nigeria
Hantavirus- Have had outbreaks in 4 corners of the US
West Nile Virus- reported in more than 40 states last year
Eastern Equine Encephalitis-rare but can be deadly
Influenza
what kind of virus is it
how often does it mutate
what is antigenic shift vs drift
how many people did the spanish flu kill
Influenza is an RNA virus like HIV
It is constantly mutating so the vaccine must be changed frequently
Periodically will have an antigenic shift-the influenza strain is drastically different from anything the population has been exposed to.
- Antigenic drift-slight mutation in the sequence of the prevalent strain
Spanish flu of 1918-1919 killed 20-40 million people worldwide
Avian influenza (H5N1) and H1N1 are concerning
Bacterial Threats
Legionnaire’s disease
Lyme Disease
Group A streptococci
E. coli 0157:H7 in food
Antibiotic resistance
- Natural progression of bacteria
- Improper medical use
- Use in agriculture
- MRSA
Tuberculosis (TB)
how does it rank in infectious disease worldwide
how many people are infected
when was there a resurgence
people with what disease are at a much higher risk
how is it transmitted
what is the fatility rate of those not treated
TB is the leading cause of infectious disease worldwide
- One third of the world population is infected
There was a resurgence in the US in the early 1990s
People with HIV are at a much higher risk
TB is transmitted by respiratory aerosol droplets
Fatality rate for untreated TB is 50%
Tuberculosis
what are effective but must be taken daily
what can improper use of it lead to
what is DOTS
Antibiotics are effective but must be taken daily for several months
Improper use of antibiotics leads to resistance, including multi-drug resistance—this may increase fatality rate
Directly Observed Therapy (DOTS) works!
- Best approach for preventing antibiotic resistance
In 2007, the CDC revised its requirements for overseas medical screening of applicants for immigration to the US
Tuberculosis
what are the Prime transmission sites for TB
Prime transmission sites for TB
- Homeless shelters
- Prisons
- Urban hospitals
- Riskiest behavior is breathing!
Prions
Also called transmissible spongiform encephalopathies
Rapidly progressive and total brain diseases
Not considered a bacteria or a virus- it is an infectious protein
Prions
what is another name for the disease
what stage of life does it appear
what country does it have a history and what are other names of the disease
who does the new variant affect and how do they get it
regulations have been tightened om what
Creutzfeldt-Jakob Disease (CJD)
Sporadic CJD is the most common
CJD usually appears later in life
Bovine spongiform encephalopathy (BSE) or “mad cow disease” has a history in Britain
New variant of CJD (vCJD) in the UK affects younger people- thought to be caused by eating infected beef
Regulations have been tightened on animal feed
Prions
what are the symptoms
what is there a deficit in
how long does it take to progress
Clinical presentation of CJD:
Fatigue, sleep disturbances, weight loss, headaches, anxiety, vertigo, malaise, poorly defined pain
Deficits in higher cortical function
Progresses over weeks to months to profound dementia
Prions
what is another name for it
which people was it found and during what years
what disease does it result and what are the physical effects
what does it eventually lead to
how did people get this disease and in what gender
Kuru
Found in Fore people of Papua New Guinea in the 1950-60’s
Neurological disease is characterized by progressive loss of coordination and control over muscle movements
Eventually leading to death
Resulted from funeral rituals of cannibalism mostly in women because they ate the brain
Public Health Response to Emerging Infections
what is there a global surveillance for
what is improved
what is there a reduction in and what can be done as a response
Global surveillance of potential epidemics
Veterinary surveillance
Improved public health capacity
Reduction of inappropriate use of antibiotics
- Educate to not use antibiotics for viral infections
