BA.5: The ‘worst variant’ is here

In Europe, the Omicron subvariants are powering a spike in cases of about 25%, though Dr. Michael Ryan, the executive director of WHO’s Health Emergencies Program, has said that number may actually be higher, given the “almost collapse in testing.” BA.5 is on the march in China, ratcheting anxieties that major cities there may soon re-enforce strict lockdown measures that were only recently lifted. And the same variant has become the dominant strain in the United States, where it accounted for 65% of new infections last week, according to the Centers for Disease Control and Prevention (CDC).

As for how to manage the new wave, Jha urged Americans aged 50 and older to get second booster shots. Adults who are up to date with vaccinations are less likely to be hospitalized than those who are unvaccinated. But only about one in four adults in the US over 50 have gotten their recommended second boosters, data collected by the CDC show.

In other words, BA.5 can easily evade immunity from previous infections and vaccines, increasing the risk of reinfection. Though the variant does not appear to lead to more severe illness, in an interview with CNN on Monday, Topol said that given the extent of BA.5’s immune evasion, he expects to see an escalation in hospitalizations, as we’ve seen in Europe and elsewhere that the variant has taken root. “One good thing is it doesn’t appear to be accompanied by the ICU admissions and the deaths as previous variants, but this is definitely concerning,” he added.

Public health experts in the US may take some solace from the trajectory of the variant in Europe. WHO’s Ryan said last week that while many European countries are experiencing a jump in hospitalizations, “what we’re not seeing is an increase in intensive care unit admissions, so the vaccines are very much still working and it is those gaps in immunity that are causing the problem.”

But still, steep reductions in Covid-19 surveillance worldwide are hindering epidemiologists’ efforts as they race to trace the virus’ evolution.

“New waves of the virus demonstrate again that the Covid-19 [pandemic] is nowhere near over,” he added.

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Q: How should I protect myself amid the new Covid-19 wave?

“I don’t think that most people should have to change their daily activities, but I do think people need to be aware of their risk of contracting Covid-19 if they don’t take additional precautions,” Wen said. The question to ask yourself, she added, is this: How much do I want to continue to avoid infection?

For individuals who want to reduce their risk, Wen advises that they stay up to date with their boosters (in the US, everyone age 5 and older can receive a first booster, and those 50 and older can receive a second booster for a total of four shots). She also recommends wearing a high-quality N95 mask or equivalent in indoor, crowded settings, and staying outside for large gatherings as much as possible — something easier to do in the summertime.

“For those who find masks uncomfortable, I’d encourage mask-wearing in the highest-risk settings — for example, mask while in a crowded security line at the airport and during boarding and deplaning,” she said.

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Drug-resistant infections and deaths have risen among hospital patients

A special report released Tuesday by the CDC found that more than 29,400 people died from antimicrobial-resistant infections in the first year of the pandemic — nearly 40% of those deaths were among people who got the infection while in the hospital. The full number is probably even higher, given that data for half of the 18 pathogens identified as threats are unavailable or delayed.

WHO has called antimicrobial resistance a “silent pandemic,” and drug-resistant infections were linked to nearly 5 million deaths globally in 2019. The Covid-19 pandemic probably contributed to the increased risk in the US, particularly because many people delayed care or left infections untreated — either because of closed clinics or fear of exposing themselves to Covid-19 — which can increase the risk of developing drug resistance.

Pulse oximeters don’t work as well for people of color

Often when Dr. Thomas Valley sees a new patient in the intensive care unit at Michigan Medicine in Ann Arbor, he clamps a pulse oximeter on their finger — one of the many devices he uses to gauge their health and what course of care they require, whether they are a child having seizures, a teenage car accident victim or an older person with Covid-19.

But recently, Valley, an assistant professor in the University of Michigan’s Division of Pulmonary and Critical Care, realized that the small device may yield less accurate oxygen readings in patients with dark skin. If the device isn’t calibrated correctly, the darker pigmentation can affect how the light is absorbed by the sensor, leading to flawed oxygen readings and patients being discharged when they shouldn’t.

TOP TIP

Advice for anxious new moms

Edith Bracho-Sanchez, director of pediatric telemedicine and assistant professor of pediatrics at Columbia University Irving Medical Center, didn’t think she’d be an anxious mom. But that changed when she had her son. “I stress over every decision I make for William. I make long pro and con lists, I discuss everything with my partner, sleep on things and ultimately, I pray,” she wrote in a recent column for CNN.

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