The World Health Organization warned on Wednesday that the continued circulation of the Delta variant and the emergence and rapid spread of Omicron could create a “tsunami” of infections that could overwhelm health systems, though high US health officials pointed out that early data showed Omicron infections producing milder disease.
The global average for new cases hit a new record high of more than 930,000 on Tuesday, according to a New York Times database. The previous record was over 827,000, reached at the end of April.
“Delta and Omicron are now twin threats that are pushing the number of cases to a record high, leading to spikes in hospitalizations and deaths,” Dr Tedros Adhanom Ghebreyesus, WHO Director-General, said at the meeting. a press conference in Geneva. “I am very concerned that Omicron, being highly transmissible and spreading at the same time as Delta, is leading to a tsunami of cases.”
But alongside the warnings, US officials and leading scientists at the UN agency said the first data from where Omicron was spreading offered cautiously positive signs.
Dr Rochelle P. Walensky, director of the Centers for Disease Control and Prevention, told a White House press conference that although cases had increased by about 60% over the past week, to reach about 240,000 recorded cases each day, hospitalizations and deaths hinted at a milder wave of the virus.
“Although our cases have increased significantly from last week, hospitalizations and deaths remain relatively low at this time,” she said, noting an average of seven days of hospitalizations of 9,000 per day, an increase of about 14% compared to last week. The seven-day average of daily deaths stood at about 1,100 per day, she added, a drop of about 7%.
“This could be due to the fact that hospitalizations tend to delay cases by about two weeks,” she said, “but could also be due to the first indications that we have seen in other countries like the ‘South Africa and the United Kingdom – Omicron disease, especially in the vaccinated and vaccinated.
Citing a series of international studies showing more moderate Omicron results, Dr Anthony S. Fauci, chief medical adviser to President Biden, said at the same press conference that “the pattern and disparity between cases and hospitalizations strongly suggest that there will be a lower hospitalization – report to the case when the situation becomes clearer.
WHO scientific director Dr Soumya Swaminathan said the first real-world data indicated that the link between the number of infections and hospitalizations had been “disrupted”.
She warned that the evidence on Omicron was only emerging. “We still cannot predict what this virus will do,” she said.
As it became increasingly clear that those vaccinated were infected with Omicron, meaning that there was a reduction in the ability of vaccines to neutralize the virus, the first evidence on the protection that vaccination could provide were positive.
Vaccines, she said, “always seemed to protect” against serious illness and death. But it was a complicated equation that had to take into account a multitude of factors – including the clinical vulnerability of those infected – and there just wasn’t enough data.
Dr Mike Ryan, WHO’s emergency program chief, said Omicron has yet to make its way into all parts of society, including the most vulnerable and unvaccinated populations.
Outbreaks of Omicron around the world, he said, started mostly in younger age groups and the variant is only now spreading in older populations.
“I think we will always see a decoupling of cases and serious illnesses,” he said. But the large number of daily cases – the “force of infection” – could lead to an increase in the number of patients and increased pressure on health systems.
He also noted that even in countries where vaccines are plentiful, there were large pockets of unvaccinated people, and it was simply too early to know if Omicron itself is less virulent than previous variants.
Dr Tedros said “the ongoing narrative that it’s milder or less severe” could be dangerous as high transmission rates alone could lead to increased hospitalizations and deaths.
“We must not undermine the bad news with the good news,” he said. “There are both elements here.”