COVID

Grandparents are a majority of the pandemic’s death toll

A CDC database of sewage data from communities around the nation could provide earlier warning of outbreaks and new viral variants

The reports’ authors say that the novel coronavirus, or SARS-CoV-2, jumped from animals sold at the market to people twice in late 2019—but some scientists want more definitive evidence

Vaccination definitely lowers the odds, but the exact answer is hard to find

Infectious disease expert William A. Haseltine cautions that a coronavirus variant could emerge with the transmissibility of Omicron and the deadliness of the original SARS

Specific mutations hide the COVID-causing variant from the immune system and give it a new route into more cells

Hamsters are only the second species known to have spread SARS-CoV-2 to humans

Hamsters eating Cocoa Krispies reveal inflammation pathways from the olfactory system to the brain

My colleagues and I use a protocol to inoculate safely, and the CDC needs to revise its recommendations

The huge number of Omicron infections could add a lot more people with disabling long-term symptoms. Vaccinations could blunt the impact

The new normal this winter is longer drives for kids’ tests, multiday waits for results, drug-store restock alerts and social media tips

Vaccine makers worry yet another variant will start dominating in the months it takes to roll out shots against this one