VIRUS TODAY: Pfizer says vaccine can work against variants

Here’s what’s happening Friday with the pandemic in the U.S.:

THREE THINGS TO KNOW TODAY

— New research suggests the COVID-19 vaccine made by Pfizer and BioNTech can still work against a mutated coronavirus. Two easier-to-spread new variants of the virus have the world on edge. One was discovered in Britain, the other in South Africa, but they share a common mutation. Pfizer researchers say lab tests show that mutation doesn’t block the vaccine. But more tests are needed to see if an additional mutation is cause for concern. The preliminary study was posted on an online research site late Thursday and has not been reviewed by other experts.

— Facing a massive surge in cases, California has been issuing waivers allowing hospitals to temporarily bypass the nation’s only strict nurse-to-patient ratios. Nurses say that being forced to take on more patients is pushing them to the brink of burnout and affecting patient care. At least 250 of about 400 hospitals in California have been granted 60-day waivers. They allow ICU nurses to care for three instead of two people and emergency room nurses to oversee six patients instead of three. Nurses in other states have demanded law-mandated ratios like those in California but so far have failed to get them.

— World Health Organization experts have issued recommendations saying that the interval between administration of two doses of the Pfizer-BioNTech vaccine can be extended to up to six weeks. WHO’s Strategic Advisory Group of Experts on immunization formally published its advice, saying an interval of 21 to 28 days between the doses is recommended. But the U.N. health agency also noted some countries face “exceptional circumstances of vaccine supply constraints combined with a high disease burden,” and some have been considering delaying the administration...