Immunology

'Natural immunity' from omicron is weak and limited, study finds

In unvaccinated people, infection with the omicron variant of SARS-CoV-2 provides little long-term immunity against other variants, according to a new study by researchers at Gladstone Institutes and UC San Francisco (UCSF), ...

Diseases, Conditions, Syndromes

Canada eases virus travel measures for kids aged 5 to 11

Unvaccinated children aged five to 11 traveling with a fully vaccinated adult will no longer need a COVID-19 test to enter Canada beginning Monday, the federal government said.