The number of children in American hospitals with covid-19 is rising fast

In many countries where the Omicron variant has taken hold, the number of children hospitalised with covid-19 is rising quickly. In America, more are in hospital with the disease than ever before, including five times as many under-fives as in January last year. In England, in the week to January 9th, the hospitalisation rate for that age group was around 14 per 100,000, the highest for any group under 55.

These increases have been caused in part by the greater transmissibility of Omicron, which means more children are being infected with covid. But it is possible that the variant also poses a greater risk to youngsters. The Economist’s analysis finds that in America the share of children under five who caught the disease and needed hospital treatment has risen. The case-hospitalisation ratio in the last two weeks of December was 50% higher than in the two weeks before Omicron was first detected.

Data from New York state, released on January 7th, suggest something similar. Its health department found a near 50% increase in hospital admissions per 100,000 cases in children aged four or younger after the variant was first detected, and a 70% increase in unvaccinated children aged five to 11 (but a decrease in those over the age of 12). Doctors have speculated that this is because Omicron reproduces higher in the respiratory tract than previous variants, causing milder symptoms in adults as the virus does less damage to the lungs, but worse ones in children, because their smaller airways can become blocked more easily.

Figures on hospitalisations tend to fluctuate over time even without the emergence of new variants, so the increases are far from definitive proof that Omicron is riskier for children. Differences in vaccination rates provide another potential explanation. In America, 63% of adults are fully vaccinated and 24% have had a booster shot. Fewer children have had the jab. No shots have been approved for those aged four and younger, and only 18% of five- to 11-year-olds have been fully vaccinated. The proportion of people being admitted to hospital “with” rather than “for” covid has also risen.

Evidence on the matter is still emerging. A report from Britain’s health-security agency suggests that, for children above the age of five, Omicron presents a lower risk of hospitalisation than Delta. Other British data show that, although more infants are being admitted to hospital with covid, the number in intensive care, the percentage needing ventilation and the average length of their stay have fallen compared with previous waves. The vast majority of children infected with covid experience mild illness and are far less likely than older folk to need hospital treatment. Parents should still worry more about themselves than about their offspring. ■

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