As COVID-19 variants have emerged, so have questions about the effectiveness of tests for infection. While the risk of mutations significantly limiting their ability to detect the novel coronavirus is thought to be relatively low, companies that make COVID-19 tests are moving quickly to enhance and revalidate their products.

By mid-January 2021, the U.K., South Africa and Brazil had confirmed that “variants of concern” were driving massive surges in COVID-19 cases in their countries. Once alerted, other nations found these troubling strains rapidly multiplying within their populations as well. At the time, the world had reported 90 million cases, creating abundant opportunities for the coronavirus to mutate. Of those cases, the virus in just 360,000 had been sequenced – and nearly all of them from just a handful of countries.

As of the end of January, SARS-CoV-2 has demonstrably infected more than 100 million individuals globally. It has killed more than 2 million. And the long-term sequelae of COVID infections – to say nothing of the health consequences of grief, social isolation and widespread economic distress – are still unfolding and will be for years to come.

LONDON – After a number of equivocal small studies, the U.K. Recovery trial has applied its heft to turn in statistically significant evidence that the rheumatoid arthritis treatment Roactemra (tocilizumab) reduces mortality in hospitalized COVID-19 patients.

Limited manufacturing capacity, supply chain disruptions and a dearth of personnel with specialized skills are all challenges vaccine makers are facing as they race to produce contracted quotas of COVID-19 vaccines that were developed and authorized in record time.