Colorized scanning electron micrograph of an apoptotic cell (blue) infected with SARS-COV-2 virus particles (red), also known as novel coronavirus, isolated from a patient sample. Image captured at the NIAID Integrated Research Facility (IRF) in Fort Detrick, Maryland. Photo: National Institute of Allergy and Infectious Diseases, NIH/Handout via REUTERS. In a study about how COVID-19 variants are formed, researchers in Israel have found that patients with a weakened immune system are at risk for chronic infection and can develop highly mutated forms of the virus, though these may be less likely to spread to others. “This study highlights the importance...