Yet again, the U.S. is trudging into what could be another COVID-19 surge, with cases rising nationally and in most states after a two-month decline. One big unknown? “We don’t know how high that mountain’s gonna grow,” said Dr. Stuart Campbell Ray, an infectious disease expert at Johns Hopkins University. No one expects a peak nearly as high as the last one, when the contagious omicron version of the coronavirus ripped through the population. But experts warn that the coming wave – caused by a mutant called BA.2 that’s thought to be about 30% more contagious – will wash across the nation. They worry that hospitalizations, which are already ticking up in some parts of the Northeast, will rise in a growing number of states in the coming weeks. And the case wave will be bigger than it looks, they say, because reported numbers are vast undercounts as more people test at home without reporting their infections or skip testing altogether. At the height of the previous omicron surge, reported daily cases reached into the hundreds of thousands. As of Thursday, the seven-day rolling average for daily new cases rose to 39,521, up from 30,724 two weeks earlier, according to data from Johns Hopkins collected by The Associated Press. Dr. Eric Topol, head of Scripps Research Translational Institute, said the numbers will likely keep growing until the surge reaches about a quarter the height of the last “monstrous” one. BA.2 may well have the same effect in the U.S. as it did in Israel, where it created a “bump” in the chart measuring cases, he said. Also read: Fewer boys return to schools than girls after long Covid hiatus: Study Keeping the surge somewhat in check, experts said, is a higher level of immunity in the U.S. from vaccination or past infection compared with early winter. But Ray said the U.S. could wind up looking like Europe, where the BA.2 surge was “substantial” in some places that had comparable levels of immunity. “We could have a substantial surge here,” he said. Both experts said BA.2 will move through the country gradually. The Northeast has been hit hardest so far — with more than 90% of new infections caused by BA.2 last week compared with 86% nationally. As of Thursday, the highest rates of new COVID cases per capita over the past 14 days were in Vermont, Rhode Island, Alaska, New York and Massachusetts. In Washington, D.C., which also ranks in the top 10 for rates of new cases, Howard University announced it was moving most undergraduate classes online for the rest of the semester because of “a significant increase in COVID-19 positivity” in the district and on campus. Some states, such as Rhode Island and New Hampshire, saw the average of daily new cases rise by more than 100% in two weeks, according to Johns Hopkins data. In New Hampshire, the increase in cases comes two weeks after the closure of all 11 state-managed vaccination sites, and the governor is being pressured by some advocates to reverse course. Joseph Wendelken, spokesperson for the Rhode Island Department of Health, said the metric they are most focused on right now is hospitalizations, which remain relatively low. About 55 COVID-19 patients are hospitalized, compared with more than 600 at one point in the pandemic. Officials credit high vaccination rates. State statistics show 99% of Rhode Island adults are at least partially vaccinated and 48% have gotten the booster dose that scientists say is key in protecting against severe illness with omicron. Vermont also has relatively high levels of vaccination and fewer patients in the hospital than during the height of the first omicron wave. But Dr. Mark Levine, the health commissioner there, said hospitalizations and the numbers of patients in intensive care units are both up slightly, although deaths have not risen. Data from the Centers for Disease Control and Prevention shows that new hospital admissions of patients with confirmed COVID-19 were up slightly in New England and the New York region. On the West Coast, modelers from Oregon Health & Science University are projecting a slight increase in hospitalizations over the next two months in that state, where cases have also risen steeply. As the wave moves across the country, experts said states with low rates of vaccination may face substantially more infections and severe cases that wind up in the hospital. Ray said government leaders must be careful to strike the right tone when talking to people about protecting themselves and others after COVID restrictions have largely been lifted. Philadelphia recently became the first major U.S. city to reinstate its indoor mask mandate after a sharp increase in infections. But Vermont’s Levine said there are no plans to bring back any of the restrictions that were imposed earlier during the pandemic. “It’s going to be hard to institute restrictive, draconian measures,” Ray said. “Fortunately, we have some tools that we can use to mitigate risk. And so I hope that leaders will emphasize the importance for people to watch the numbers,” be aware of risks and consider taking precautions such as wearing masks and getting vaccinated and boosted if they’re not already. Lynne Richmond, a 59-year-old breast cancer survivor who lives in Silver Spring, Md., said she plans to get her second booster and keep wearing her mask in public as cases rise in her state and nearby Washington, D.C. “I never really stopped wearing my mask…I’ve stayed ultra-vigilant,” she said. “I feel like I’ve come this far; I don’t want to get COVID.” At the 250-bed New Hampshire Veterans Home in Tilton, staff are still wearing masks and social distancing. Veterans are allowed limited excursions to places like an antique race car museum and restaurants where they can have a separate room and the wait staff is masked. Vigilance is a good strategy, experts said, because the coronavirus is constantly throwing curveballs. One of the latest: even more contagious subvariants of BA.2 found in New York state, known as BA.2.12 and BA.2.12.1. And scientists warn that new and potentially dangerous variants could arise at any time. “We shouldn’t be thinking the pandemic is over,” Topol said. “We should still keep our guard up.”

The U.S. is urging that everyone 12 and older get a COVID-19 booster as soon as they’re eligible, to help fight back the hugely contagious omicron mutant that’s ripping through the country. Boosters already were encouraged for all Americans 16 and older, but Wednesday the Centers for Disease Control and Prevention endorsed an extra Pfizer shot for younger teens — those 12 to 15 — and strengthened its recommendation that 16- and 17-year-olds get it, too. “It is critical that we protect our children and teens from COVID-19 infection and the complications of severe disease,” Dr. Rochelle Walensky, the CDC’s director, said in a statement Wednesday night. “This booster dose will provide optimized protection against COVID-19 and the Omicron variant. I encourage all parents to keep their children up to date with CDC’s COVID-19 vaccine recommendations,” she said. Also read: FDA paves way for Pfizer COVID-19 vaccinations in young kids Vaccines still offer strong protection against serious illness from any type of COVID-19, including omicron — what experts say is their most important benefit. But the newest mutant can slip past a layer of the vaccines’ protection to cause milder infections. Studies show a booster dose at least temporarily revs up virus-fighting antibodies to levels that offer the best chance at avoiding symptomatic infection, even from omicron. Earlier Wednesday, the CDC’s independent scientific advisers wrestled with whether a booster should be an option for younger teens, who tend not to get as sick from COVID-19 as adults, or more strongly recommended. Giving teens a booster for a temporary jump in protection against infections is like playing whack-a-mole, cautioned CDC adviser Dr. Sarah Long of Drexel University. But she said the extra shot was worth it to help push back the omicron mutant and shield kids from the missed school and other problems that come with even a very mild case of COVID-19. Also read: Pfizer asks FDA to OK COVID-19 booster shots for all adults More important, if a child with a mild infection spreads it to a more vulnerable parent or grandparent who then dies, the impact “is absolutely crushing,” said panelist Dr. Camille Kotton of Massachusetts General Hospital. “Let’s whack this one down,” agreed Dr. Jamie Loehr of Cayuga Family Medicine in Ithaca, New York. The vaccine made by Pfizer and its partner BioNTech is the only option for American children of any age. The CDC says about 13.5 million children ages 12 to 17 — slightly more than half of that age group — have received two Pfizer shots. Boosters were opened to the 16- and 17-year-olds last month. Wednesday’s decision means about 5 million of the younger teens who had their last shot in the spring are eligible for a booster right away. New U.S. guidelines say anyone who received two Pfizer vaccinations and is eligible for a booster can get it five months after their last shot, rather than the six months previously recommended. But one committee member, Dr. Helen Keipp Talbot of Vanderbilt University, worried that such a strong recommendation for teen boosters would distract from getting shots into the arms of kids who have not been vaccinated at all. The advisers saw U.S. data making clear that symptomatic COVID-19 cases and hospitalizations are between seven and 11 times higher in unvaccinated adolescents than vaccinated ones. While children do tend to suffer less serious illness from COVID-19 than adults, child hospitalizations are rising during the omicron wave -- the vast majority of them unvaccinated. During the public comment part of Wednesday’s meeting, Dr. Julie Boom of Texas Children’s Hospital said a booster recommendation for younger teens “cannot come soon enough.” The chief safety question for adolescents is a rare side effect called myocarditis, a type of heart inflammation seen mostly in younger men and teen boys who get either the Pfizer or Moderna vaccines. The vast majority of cases are mild — far milder than the heart inflammation COVID-19 can cause — and they seem to peak in older teens, those 16 and 17. The FDA decided a booster dose was as safe for the younger teens as the older ones based largely on data from 6,300 12- to 15-year-olds in Israel who got a Pfizer booster five months after their second dose. Israeli officials said Wednesday that they’ve seen two cases of mild myocarditis in this age group after giving more boosters, 40,000. Earlier this week, FDA vaccine chief Dr. Peter Marks said the side effect occurs in about 1 in 10,000 men and boys ages 16 to 30 after their second shot. But he said a third dose appears less risky, by about a third, probably because more time has passed before the booster than between the first two shots.

North, Central and South Americas still bear the global burden of 40% of Covid-19 fatalities and more than 25% of cases, according to the World Health Organization (WHO). Almost 1 million cases were reported in the Americas last week, said Maria Van Kerkhove, technical lead on Covid-19 for the WHO, Monday. Read:US tops 30 million confirmed cases of COVID-19 In Brazil, around 300,000 cases were recorded last week; in the US, more than 200,000 cases were reported, Maria added. She warned of a peak in the transmission level that has been observed in the region, saying that "they are stuck at a high level of intensity, and cannot quite bring that transmission down." An 11.5% rise in global cases were seen last week, with Europe and the Western Pacific being hit the hardest, Maria said. "The Americas saw a moderate increase of 0.5%, but some countries were plagued by really sharp spikes in transmission possibly due to new variants." Meanwhile, US life expectancy fell by a year and a half in 2020, the largest one-year decline since World War II, according to the Centers for Disease Control and Prevention. Read: Global Covid cases near 190 million The covid-19 pandemic is responsible for around 74% of the overall life expectancy decline. More than 3.3 million Americans died last year, far more than any other year in US history, with Covid-19 accounting for about 11% of those deaths, the health officials said. However, the virus' role varied by race and ethnicity. It was responsible for 90% of the decline in life expectancy among Hispanics, 68% among white people and 59% among Black Americans. For decades, US life expectancy was on the upswing. But that trend stalled in 2015, for several years, before hitting 78 years, 10 months in 2019. Last year, it fell to about 77 years, four months, the CDC said. "South America, Central America and other places around the world need more vaccines if they are going to break this deadly cycle of cases," said Michael Ryan, executive director of the WHO's Health Emergencies Program. 

The confirmed COVID-19 cases have surpassed 42.9 million globally as of Monday morning, according to the latest tally from Johns Hopkins University (JHU).