By Graham Lawton
WHEN the novel pneumonia circulating in China was confirmed to be caused by a coronavirus, an already troubling situation suddenly got that bit worse. As a rule, coronaviruses don’t produce a very strong “immune memory”: the long-lasting response that allows our bodies to thwart a subsequent attack, and which makes vaccines possible. When reports emerged from Japan and China of people who had been given the all-clear catching the virus again, immunologists’ worst fears seemed to be confirmed.
But seven months later, hopes are …