• European officials report that countries in the bloc made decisions to suspend AstraZeneca ‘s coronavirus vaccine individually, without  coordination between countries or with the EU executive in Brussels. Source
Science publishes a summary of reports of severe blood disorders among recipients of the AstraZeneca coronavirus vaccine; researchers do not know whether the vaccine is causing these abnormalities, or how it could be doing so. In Germany, the rate of cerebral venous thrombosis cases was higher among recent vaccine recipients than the general public during the same period ( seven versus 1), affected young people at lower risk of death from COVID-19, and was severe, leading health authorities to pause vaccination.

Theories include a very strong immune reaction, triggered by pre-existing COVID-19 and the vaccine, or that specific vaccine batches which were either contaminated or higher-dose, could be the culprit. The complement system – which plays an important role in the innate immune response – is likely to be involved, since they can cause abnormal clotting and bleeding in response to pregnancy, infections, vaccines, cancer and inflammation. Overall, although experts raised caution about these severe events, most agreed that the benefits of uninterrupted vaccination outweighed risk. Source
Lancet publishes an observational study looking at coronavirus reinfection among 533 381 people originally tested before June 2020 and 525,339 who were re-tested during the second surge (September- December 2020). Overall, 72 people tested positive a second time, with people age 65 years and over  more likely to be reinfected than younger people, regardless of gender; the overall protection against reinfection was 80 percent in younger people versus 47 percent in those age 65 and over. Source
• European Commission President Ursula von der Leyen said that the EU – which has exported 41 million vaccine doses to 33 countries since February – may stop exports of coronavirus vaccines to countries with higher vaccination rates, so it can prioritize vaccinating  Europeans. Source
• As Brazil faces record-breaking rates of new coronavirus infections and deaths and a hospital system that is near to collapse, President Bolsonaro appoints his fourth Minister of Health in less than one year. Source
• The Washington Post publishes a warning to the world about Brazil’s coronavirus “disaster”. Experts warn that the country’s uncontrolled epidemic could lead to more dangerous strains – which could spread to other countries in the region. Source
• Former President Trump, who repeatedly downplayed the pandemic, recommends coronavirus vaccines amid reports that a third of Republicans do not plan to be vaccinated. Source
• The EU proposes a Digital Green Certificate that would allow residents of member states to travel freely between countries with proof of coronavirus vaccination, or a negative test result, or documentation of recovery from COVID-19 Source
• COVAX delivered its first shipment of 37,440 doses of the Pfizer/BioNTech vaccine and 24,000 doses of the AstraZeneca vaccine  to the occupied West Bank and the blockaded Gaza Strip. Source
• In the UK, the NHS warned of a month-long reduction in vaccine supplies, with all appointments in April to be cancelled; the cause of the shortage is unclear. Source
• Serbia, home to Europe’s second-highest vaccination rate (after the UK), attributes it to broad negotiations and deals with Pfizer/BioNTech and vaccine producers in Russia and China. Source
• FDA’s acting Commissioner, Janet Woodcock, announces that the US government  has stopped distributing the monoclonal antibody bamlanivimab in California, Arizona and Nevada, where a prevalent coronavirus variant, B.1.429/B.1.427, is not susceptible to it. Source
• Tanzania’s president –  and coronavirus denialist- John Magufuli, dies after a two-week absence from public view and coronavirus deaths among senior government officials sparked rumors he was gravely ill with COVID-19; state radio announced heart disease as the cause. Source