A single vaccine dose delivered to nose aims to protect children and adults against COVID.

Updated Pfizer-BioNTech and Moderna bivalent boosters contain spike proteins from the original and BA.4 and BA.5 omicron variants.

COVID-19 test results provide valuable data that public health departments can use to assess needs and modify responses.

COVID can also affect the gut lining, which may allow pathogenic bacteria to enter the bloodstream and cause secondary infections.

Many people with long COVID are falling through the cracks of a system that was difficult to navigate even before the pandemic.

These three respiratory illnesses—and others—share many of the same symptoms.

Researchers found that today’s COVID rapid antigen tests can identify all current variants of concern and interest.

Study finds that HIV-positive people are four times more likely to experience long-term COVID symptoms.

The small study found no evidence of delayed development of antibodies in participants who experienced rebound after taking Paxlovid.

Research on links between tenofovir, SARS-CoV-2 infection and COVID severity have yielded mixed results, but new study suggests it helps.