Lancet publishes a population-based longitudinal study on prevalence and durability of antibodies to SARS-CoV-2 in Wuhan, China, with data from more than 9,000 residents. Overall, 5.6 percent were antibody-positive – meaning that much of Wuhan’s population is still vulnerable to COVID-19. Over 80 percent of antibody-positive people had asymptomatic infections. Overall, 39·8 percent of those who were infected had neutralizing antibodies, which  were sustained for at least nine months – regardless of whether they experienced  symptoms. Source
• In Denmark, where AstraZeneca’s coronavirus vaccine remains suspended until Thursday, two people have had cerebral hemorrhages – one fatal-  after receiving the vaccine; the Danish Medicines Agency is investigating whether they could be a vaccine side effect. European researchers have identified antibodies that may be responsible. Source
• Pakistan’s Prime Minister Imran Khan tested positive for COVID-19 two days after getting his first dose of the Sinopharm coronavirus vaccine;  according to his aide, he is experiencing mild symptoms but is able to work from home. Source
• Some people living with long COVID report an improvement in their symptoms after being vaccinated, while others report no change, or have worsened. A pre-print article details changes in symptoms among 44 people with long COVID who were vaccinated and 22 who were not. Researchers noted a small improvement among vaccinated people, regardless of  vaccine type – overall, 14.3 percent of unvaccinated people reported worsening symptoms versus 5.6 percent  of people who were vaccinated, while 15.4 percent of unvaccinated people reported an improvement in their symptoms versus 23.2 percent of people who received the vaccine. An equal number of people in each group reported no change in their symptoms. The authors recommended vaccines for people with prolonged symptoms. Source
• After a surge in coronavirus infection rates, authorities in the Indian city of Mumbai will conduct random – and mandatory  – rapid antigen tests in malls (where people will be charged for their test) and other crowded places (where they will not be charged for tests). Source
• AstraZeneca announced that it will provide 230 million coronavirus vaccine doses to 142 countries in the next few months. Source
• Sri Lanka approves Sinopharm’s coronavirus vaccine for emergency use. Source
• Brazilian government officials are negotiating with the US to obtain surplus coronavirus vaccines. Source
• Although Greece is reporting its highest number of new daily infections in a year and its healthcare system is stretched by caring for people with COVID-19, it opened outdoor tourist attractions such as the Acropolis before the official  reopening on 14 May. Source