5 things to know about COVID-19 this week

As the COVID-19 pandemic continues, new information is coming out constantly. Here are five important developments from the past week.

1. Experts worry that variants may lead to more COVID-19 virus reinfections, the Associated Press reported on Monday. Some emerging research suggests that a second infection can occur in those who mounted a weak defense the first time. Studies in South Africa and Brazil, where more virulent variants of the virus have originated, have found that at least some percentage of the population is vulnerable to reinfection.

   The Brazilian city of Manaus is of particular interest, as COVID cases there are continuing to surge, even though it is believed that 75% of the population had already been infected.

2. Dr. Anthony Fauci said on MSNBC on Monday that both doses of the two currently approved COVID-19 vaccines are “critical” in the effort to stay ahead of these emerging variants. Dr. Fauci also stressed that the U.S. will need to continue vaccinating as many people as possible while sticking to the current two-dose plan.

   Some have called for delaying second doses and trying to give more people a single shot first, but Dr. Fauci and other experts maintain that one dose of the current vaccines in circulation is not enough to stem the pandemic. “If you have a lesser immune response, which is what you’re getting after that first dose, then you are more likely to wound this virus than kill it,” Paul Offit, MD, a leading vaccine researcher, said last week.

3. South Africa is suspending its rollout of the AstraZeneca vaccine due to a small study that found it to be less effective against the more virulent variant circulating in that country. The study, which was published on Sunday but has not yet been peer-reviewed, reported that the AstraZeneca vaccine only offers minimal protection against mild to moderate disease caused by the South African COVID-19 variant.

   Because the study only included people at low risk of severe illness or death from the disease, researchers say it does not address whether the vaccine protects against serious illness, hospitalization or death in patients who contract the South African variant.

   Sarah Gilbert, a professor of vaccinology at the University of Oxford, which developed the vaccine with AstraZeneca, said that efforts are already underway to modify the vaccine in a way that provides protection to emerging variants. That could include booster shots, if necessary.

4. COVID-19 cases are dropping at US homes for the elderly, due in large part to immunization efforts, the AP reported last Friday. Health officials are encouraged by current infection rates reported by nursing homes across the country, which were 31% lower in January than they were prior to the rollout of the Pfizer and Moderna vaccines.

   The federal government reports that 1.5 million residents of long-term care facilities have at least gotten their first dose of the vaccine. An industry group reports that 13% of such facilities are now free of the virus.

5. NPR asked infectious disease experts about the relative safety of a non-vaccinated person visiting a vaccinated, elderly relative. While seniors who have been vaccinated are protected to some extent against COVID-19 infection, physicians still advise that they, as well as those who are not vaccinated, continue to take steps to avoid transmitting the virus.

   The FDA has reported that those over 65 may not develop the immune response necessary to make visiting without a mask risk-free. Though fully vaccinated seniors can likely visit safely in small groups, protocols can only be fully relaxed once the U.S. achieves herd immunity.