4 types of viral hemorrhagic fever viruses
Filoviruses (Marburg/Ebola), Flaviviruses (Dengue/Yellow fever), Bunyaviruses (Hanta), Arenaviruses (Lassa)
Agent, Host and Environment
Route of infection of viral hemorrhagic fever
Inhalation (arena and bunya), arthropod (flavi, bunya) contact with body fluids (filo, arena) and artificially aerosolized.
5 species of ebola
Ebola Zaire (80% fatality rate), Ebola Sudan (50% fatality), Tai Forest, Bundibugyo (20% fatality rate) and Reston virus (Phillipines)
Most likely reservoir of ebola
Why is the current outbreak in West Africa worse than past ebola outbreaks?
Incubation period for ebola
Most likely 3-13 days. The early febrile period lasts 0-3 days (maculopapular rash, pharyngitis, conjunctivitis). GI symptoms start 3-10 days after infection (vomiting blood, gingival bleeding, IV site oozing). Shock from hemorrhage or recovery ensues around 7-12 days. Late complications begin around 10 days.
Microorganisms not known to cause disease, wash your hands after.
Moderate risk organisms you work with under a hood with a gown/glove and do not infect people by aerosol.
Microorganisms infect by aerosol, workers wear mask, get vaccinated, therapeutic interventions exist if infected.
Microorganisms that are deadly and have no vaccination or treatment. Must wear space suit.
Setting up a field health care facility for ebola
Separate low risk regions from high risk regions and minimize invasive procedures.
What is the Ro for ebola?
If 1 person gets infected, typically 1 or 2 other people get infected. Compare this to the most infectious disease measles, with an Ro of 12-18.
Rules for treating patients with ebola
No exposed skin, N95 mask, double gloves
Key to getting out of the current ebola outbreak
Increase trust in the medical care system to get local doctors back and patients confident enough to go seek help.