A jump in COVID-19 hospitalisations of children in New York has sparked concerns in California amid a surge in Omicron variant infections.
Rong-Gong Lin II and Luke Money, writing in Los Angeles Times said that the Omicron wave hit New York before California, where cases have been surging in the last week.
According to California health officials, they are monitoring the rise in paediatric hospitalisations.
"Unfortunately NY is seeing an increase in paediatric hospitalizations (primarily amongst the unvaccinated), and they have similar (5- to 11-year-old) vaccination rates," Dr Erica Pan, the California state epidemiologist, wrote on Twitter.
"Please give your children the gift of vaccine protection as soon as possible as our case [numbers] are increasing rapidly."
The increase is concentrated in New York City and the surrounding metro area. Officials described paediatric admissions quadrupling in New York City in recent weeks, reported Los Angeles Times.
Half of the children being admitted to hospitals are younger than 5 and ineligible for vaccination.
Three-quarters of those ages 12 to 17 who were admitted into hospitals for COVID-19 were not fully vaccinated, and 100 per cent of those ages 5 to 11 who were admitted into hospitals were not fully vaccinated, said Rong and Money.
The warning about paediatric hospital admissions comes as California's public health director and health officer, Dr Tomas Aragon, warned that state modellers are predicting hospital surges for California.
"Why? Omicron is so contagious that it finds unvaccinated/non-immune people who are most vulnerable for hospitalisations and deaths," Aragon wrote.
Aragon urged people to get vaccinated and boosted; to test before risky events, as well as three to five days after them; and to consider skipping or postponing high-risk indoor gatherings.
Aragon also suggested improving ventilation and air filtration and improving the fit and quality of masks.
Health experts have increasingly urged people to upgrade their masks from cloth masks alone.
A more protective mask-wearing setup involves a cloth mask over a surgical mask, which improves the fit; an even more improved setup involves wearing those that are higher grade, such as a KF94, KN95 or N95 mask, said Rong and Money.
Dr Anthony Fauci, President Biden's chief medical advisor, recently urged people to not go to the kinds of indoor parties attended by dozens of people whose vaccination status you don't know.
Fauci said it's safer for people to attend smaller-size gatherings with family and friends in homes where everyone is known to be vaccinated and boosted, and even safer if people get rapid tests just before the event, reported Los Angeles Times.
Fauci on Sunday told ABC that recent data from Britain show that, in its Omicron wave, a lower percentage of newly infected people are needing hospitalisation.
Unvaccinated people "are the most vulnerable ones when you have a virus that is extraordinarily effective in getting to people and infecting them the way Omicron is," Fauci said in the televised interview.
Omicron "might still lead to a lot of hospitalisations in the United States."
While unvaccinated people are at the highest risk of contracting the virus and suffering severe illness, the Omicron variant's mutations increase the risk of breakthrough infections among those who are vaccinated.
Still, vaccinated people, especially those who are boosted, are expected to be generally protected from severe illness and death, unless they have a weakened immune system.
New coronavirus cases dramatically increased through Christmas in Los Angeles County.
On Tuesday, 3,052 new cases were reported; on Wednesday, 6,509; Thursday, 8,633; Friday, 9,988; Saturday, 11,930; and Sunday, 8,891.
Officials warned that coronavirus case counts over the weekend are actually an undercount because of delays in reports over the holiday, reported Los Angeles Times.
Southern California's COVID-19 hospitalisations are increasing faster than the San Francisco Bay Area's.
Since December 1, the COVID-19 hospitalisation rate in Southern California has risen by about 41 per cent, from 7.7 hospitalisations for every 100,000 residents to 10.8, reported Los Angeles Times.
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