BA.2.75 is spreading rampantly in India and has so far reached at least 20 other countries, but it doesn’t seem to be outcompeting other Omicron SARS-CoV-2 subvariants.

Studies show that a fourth mRNA vaccine dose offers the elderly and other high-risk groups strong protection against hospitalization and death from COVID-19, but experts say benefits for other populations may be more limited.

The Scientist asks Brigham and Women’s Hospital infectious disease specialist Lindsey Baden about testing for prior infections.

IgA antibodies appear to bind to specific species of commensal gut bacteria in mice, according to a study.

How scientists aim to induce an immune response against addictive drugs

Researchers are turning to the immune system for help in treating addiction and preventing overdose.

Two recent papers provide insight into possible risk factors for developing the chronic condition, including autoantibodies and diabetes.

Unlike studies of antibody-rich transfusions in hospitalized patients, which overall have not found clear benefits, a new randomized trial finds that early convalescent plasma treatment cuts hospitalizations in half.

Researchers report what appears to be the second case of a person’s immune system clearing the virus on its own.

It’s unclear whether differing odds of dying between men and women reflect inherent differences between male and female immune systems or differences rooted in gender norms.

If the immune system makes mistakes—reacting late or getting the target wrong—it can amplify the damage wrought by SARS-CoV-2.

Both of the mRNA vaccines available in the US are highly effective against severe COVID-19, but recent studies suggest that Moderna’s elicits a stronger immune response and might be better at preventing breakthrough infections.  

President Biden’s planned rollout of additional COVID-19 vaccine doses is set to begin next week, but questions remain about who should get them.