Twenty countries on four continents reported record-breaking numbers of Covid-19 cases in the past week, highlighting the strain Omicron is putting on health systems in both rich and poor countries around the world.
The World Health Organization has warned of an impending “tsunami” of infections as the highly transmissible variant of the coronavirus and the Delta strain circulate together.
According to an analysis by the Financial Times, at least five countries – including Australia, Denmark and the United Kingdom – saw increases more than double their previous highs.
The 7-day moving average of cases in the US approached 300,000 on Wednesday, its highest daily number since the pandemic began, according to the FT data tracker.
Countries are also testing much more now than in earlier stages of the pandemic, but the proportion of tests that give a positive result is increasing across the board, suggesting the rise in cases is real.
In several countries – including England, Canada and Denmark – test positivity has already risen to record highs since the beginning of the widespread community testing.
PCR and lateral flow tests are currently unavailable or difficult to obtain in a number of countries including the UK and Italy.
Australia, which once pursued a “zero Covid” policy, has seen infections rise five and a half times its previously recorded peak, the analysis shows.
Initial evidence suggests that Omicron is less severe compared to previous variants. This may be because the coronavirus has infected millions since it first appeared two years ago, giving those infected some immunity, and because of the vaccination. However, it is not yet known whether Omicron is less virulent for those who have never been vaccinated or exposed to the virus, especially those who are most susceptible.
Public health experts have warned against underestimating the effects of Omicron after concluding that the disease is milder.
“The exponential increase in cases in countries and cities around the world can put health systems under increasing pressure,” Soumya Swaminathan, WHO chief scientist, told the FT.
“A small percentage of a very large number of people can still occupy hospitals and also enormously increase the need for outpatient care,” she said.
The surge in cases has already weighed on hospitals in the United States, where vaccination rates including New York and the District of Columbia are also seeing spikes in infections.
New York governor Kathy Hochul said Wednesday that the state is sending additional medical staff and increasing bed capacity as hospitalization rates rise but remain lower compared to the same point in time last year.
“We’re basically preparing for a January surge,” she said. “We know it is coming”.
Mike Ryan, WHO emergency director, said it was likely that the virus would develop into an endemic phase, but “the virus itself is very unlikely to go away completely”.
Since Omicron was first discovered in southern Africa late last month, nations have tried to stem its spread by restricting travel or closing borders altogether and expanding booster campaigns. Omicron appears to be more transmissible than Delta and able to pierce the immunity caused by vaccines and previous infection.
Early evidence suggests that full courses of existing vaccines may be less effective at controlling the variant, although booster vaccination may help restore some of that protection. This protection is even lower for vaccines, which are mainly used in poorer countries. Johnson & Johnson was the latest company to say an extra dose of its vaccine had helped against the variant on Thursday.
In the two years since it was first discovered, the coronavirus has infected more than 284 million people and killed more than 5.4 million people worldwide, according to Johns Hopkins University, although both numbers are likely significantly underestimated.
Additional reporting from Martin Stabe in London