Communicable disease concepts Flashcards
(39 cards)
Name 5 examples of emerging/re-emerging infectious diseases
Human monkeypox; Chikungunya; Lassa fever; Dengue fever; Hantavirus pulmonary syndrome; Bunyavirus; E Coli O157:h7; Hendra virus, Nipah virus
Name 5 factors that influence the spread of an infectious disease
Transmissibility: R0 Speed of transmission: serial interval, incubation. latency, infectious period Pathogenicity Stage of epidemic Heterogeneity in transmission
What are the 7 diseases on the “Emerging priority diseases” list?
- Crimean-Congo haemorragic fever
- Ebola virus disease/Marburg virus disease
- Lassa fever
- MERS-CoV and SARS
- Nipah and henipaviral diseases
- Rift Valley Fever
- Zika
Explain ring vaccination as employed during the Congo Ebola outbreak
Once the index case is confirmed, then all close contacts (those who have had close contact with the patient/body fluids/linen, household members) and secondary contacts (household members of close contacts, extended family of close contacts) are vaccinated
What is the goal of the WHO R&D Blueprint for Action to Prevent Epidemics?
The goal is to improve the speed and effectivenss of clinical trial research before and during an epidemic
Name the 3 main features of the WHO R&D Blueprint for Action to Prevent Epidemics
- Improving coordination (global coordination mechanism, funding, communication)
- Accelerating R&D (disease prioritization, roadmaps and target product profiles, regulatory and ethical pathways)
- Developing norms and standards (clinical trial designs, data and sample sharing)
True or false: Lassa fever is asymptomatic/subclinical in 50% of cases
False: Around 80% of Lassa fever cases are asymptomatic or subclinical. In the remaining 20% of cases, non-specific symptoms develop within 2-21 days after infection
MERS-CoV is a viral respiratory disease caused by a novel coronavirus first identified in Saudi Arabia in 2012. What is its case fatality rate? A - 2% B- 5% C - 15% D - 40% E - 85%
D - 40%
Supportive care is the major treatment
What is the natural host and intermediate host of Nipah virus?
Natural host: fruit bats
Intermediate host: pigs
People have also become infected from consuming contaminated date palm sap and limited human-human transmission has also been observed
What are the at risk populations for Crimean-Congo haemorrhagic fever?
Farmers in endemic areas (in Africa, the Balkans, Middle East and Asia), abattoir workers, veterinary officers working with domestic animals, healthcare workers
What is the definition of Disease X (list 4 options)
Disease X is a pathogen currently unknown to cause human disease - there are 4 main subtypes
- Known pathogen that becomes more virulent
- Known pathogen that causes a large outbreak and reveals serious sequelae
- Known zoonotic pathogen that spills over to humans
- Unknown pathogen
What is the Ebola virus and what is Ebola virus disease?
The ebola virus is a RNA-filovirus, of which there are 5 subtypes (bundibugyo ebolavirus, Lake Victoria marburgvirus, Sudan ebolavirus, Tai Forest ebolavirus, Zaire ebolavirus). The clinical features of Ebola virus disease are as follows Phase 1 (days 0-3) early febrile Phase 2 (days 3-10) gastrointestinal (NVD) with associated persistent fever, headache, conjunctival injection, abdo pain, myalgias, delirium Phase 3 (days 7-12) shock or recovery Late complications (>10 days) - GI haemorrhage, secondary infections, meningoencephalitis, persistent neurocognitive abnormalities
Where was the initial outbreak in the 2014 West African Ebola epidemic? A. Sierra Leone B. Liberia C. Guinea D. Ivory Coast E. Senegal
C. Guinea
The epidemic was traced back to the district of Gueckedou on the border of Guinea and Liberia
What were some of the challenges in responding to the Ebola epidemic in West Africa?
Ebola virus disease has nonspecific symptoms in the early phases
Lack of effective treatments (supportive care only)
Lack of vaccine at the beginning of the outbreak
Hospitals and health centres closed due to multiple reasons - no one to deliver health care, diagnose/test infections
What are the key elements included in the definition of public health surveillance?
Ongoing (not a one-time survey) systematic collection analysis interpretation dissemination link to action
What is the difference between active and passive surveillance?
Active - health department staff call or visit health care providers on a regular basis to solicit case reports
Passive - health care providers, hospitals, labs send reports to the health department based on a set of rules and regulations
What are the attributes of a surveillance system that should be evaluated to ensure the system is meeting its objectives?
Simplicity Flexibility Data Quality Acceptability Sensitivity Positive Predictive Value Representativeness Timeliness Stability
What are some of the reasons that the outbreak of Ebola virus disease in DRC had a better outcome compared to the outbreak in West Africa?
Stronger health system
Previous experience with EVD
Rural/remote region - not in major cities
Fast response/community participants
What are the 5 goals of the Global Vaccine Action Plan?
- Achieve a world free of poliomyelitis
- Meet vaccination coverage targets in every region, country and community
- Exceed the Millenium Development Goal 4 target for reducing child mortality
- Meet global and regional elimination targets
- Develop and introduce new and improved vaccines and technologies
What is the difference between elimination and eradication of polio?
Elimination refers to the reduction to zero (or a very low defined target rate) of new cases in a defined geographical area
Eradication refers to the complete and permanent worldwide reduction to zero new cases of the disease through deliberate efforts
How many diseases have been eradicated?
One - smallpox
Discuss the achievements and challenges in global DTP vaccination
ARound 85% of infants worldwide received 3 doses of DTP vaccine in 2019. 125 member states had reached at least 90% coverage. A key challenge is that 14 million infants did not receive an initial dose of DTP vaccine and an additional 5.7 million are partially vaccinated. >60% of these children live in 10 countries: Angola, Brazil, DRC, Ethiopia, India, Indonesia, Mexico, Nigeria, Pakistan and the Philippines
Discuss key points in the global HPV vaccination campaign
Global HPV vaccine coverage is increasing and the pace of introduction is accelerating. HPV vaccine coverage varies substantially, regardless of income strata. 61% of cervical cancer cases occur in countries that have not yet introduced HPV vaccination
Name 5 vector borne diseases
Dengue fever, Yellow fever, Zika, malaria, Japanese encephalitis, Plague, Sleeping sickness, Schistosomiasis
