Topic
Epidemiology
3 questions tagged Epidemiology — spanning every one of the seven Ws.
how
How does herd immunity reduce the spread of a contagious disease?
When enough people are immune, chains of transmission are harder to maintain. That helps protect people who cannot be vaccinated or do not respond well to vaccines.
MedicineEpidemiology
how
How do disease outbreaks spread so quickly in unvaccinated populations?
If a germ finds many susceptible people, each sick person can infect several others. That creates exponential growth until transmission is interrupted by immunity, isolation or control measures.
MedicineEpidemiology
whose
Whose experiments first proved that fleas can spread plague?
Researchers in the early 20th century, especially Paul-Louis Simond, demonstrated that fleas transmit plague between rodents and humans.
Insects and arachnidsEpidemiology