With limited surveillance of Covid-19 variant, it’s déjà vu all over again
Helen Branswell writes: As health officials in the United States announced a second and possibly a third person infected with a new, more transmissible strain of the SARS-CoV-2 virus, infectious diseases experts are feeling a sense of déjà vu all over again. A little less than a year ago, the early response to the coronavirus crisis was stifled by an inability to scale up testing to detect the virus and curb its spread. Now, once again, it’s unclear how prevalent…