Infectious disease

Many theories have been offered for why the official COVID-19 toll on the Indian subcontinent has been surprisingly low. The best explanation may be the shortage of good, timely data.

Solve a puzzle about mixed dog breeds, sexual reproduction and the COVID-19 pandemic.

In the fight against viruses and other pathogens, scientists are looking beyond genes and proteins to the complex sugars, or glycans, on cell surfaces.

As COVID-19 cases continue to increase, our extensive knowledge of other coronaviruses informs our understanding.

Zoonotic diseases like influenza and many coronaviruses start out in animals, but their biological machinery often enables them to jump to humans.

Smallpox was eradicated relatively quickly, but other diseases have proved harder to eliminate. The reasons are a mix of biology and psychology.

Just as antibiotics have bred resistance in bacteria, vaccines can potentially lose their effectiveness over diseases they controlled. Researchers are working to head off the evolution of new threats.

The long, variable times that some diseases incubate after infection defies simple explanation. An idealized model of tumor growth offers a statistical solution.

Simple math shows how widespread vaccination can disrupt the exponential spread of disease and prevent epidemics.