The World Health Organization moved Tuesday to clarify its position on whether people without symptoms are widely spreading the new coronavirus, saying much remains unknown about asymptomatic transmission.
A comment by a WHO official on Monday — calling such asymptomatic transmissions ‘‘very rare’’ — touched off a furious scientific debate over the unresolved question and attracted widespread criticism of the organization.
Less than 24 hours later, the WHO convened a special news conference to walk back its comments, stressing that much remains unknown. But the comment from Monday had already spread widely and been seized upon by conservatives and others to bolster arguments that people do not need to wear masks or maintain social-distancing precautions.
The episode sparked criticism of the WHO’s public health messaging and highlighted just how fraught and easily politicized such work remains months into the pandemic.
Calling the controversy ‘‘a misunderstanding,’’ Maria Van Kerkhove, head of the WHO’s emerging disease and zoonosis unit, said that during the news conference Monday, she was trying to respond to a journalist’s question when she said asymptomatic transmission was ‘‘very rare.’’
‘‘I wasn’t stating a policy of WHO or anything like that,’’ she said. ‘‘We do know that some people who are asymptomatic, or some people who do not have symptoms, can transmit the virus on.’’
While asymptomatic transmission does occur, no one knows for sure how frequently it happens. Studies and models have suggested many of those infected never show symptoms.
And it remains an open question whether they are a large force driving transmission. Some countries using contact tracing to work backward from confirmed cases have not found many instances of asymptomatic spread, WHO officials noted.
At the same time, WHO officials acknowledged on Tuesday that some modeling studies have suggested as much as 41 percent of transmission may be due to asymptomatic people.
Adding to the confusion are differing definitions of what it means to be asymptomatic. Some people who are infected never show symptoms; specialists would consider those truly asymptomatic cases. But some show symptoms later and could be spreading the virus before those symptoms manifest; they would be considered presymptomatic cases.
Further complicating matters is the fact that for some people, symptoms are so mild — or manifest themselves in less expected ways such as diarrhea or muscle aches, instead of the more well-known fever and cough — that people aren’t aware of them until later on.
Fauci warns that coronavirus pandemic is far from over
In a wide-ranging talk to biotech executives, Dr. Anthony Fauci delivered a grim assessment of the devastation wrought around the world by the coronavirus.
COVID-19 is the disease that Fauci always said would be his “worst nightmare” — a new, highly contagious respiratory infection that causes a significant amount of illness and death.
“In a period of four months, it has devastated the whole world,” Fauci, director of the US National Institute of Allergy and Infectious Diseases, said Tuesday during a conference held by BIO, the Biotechnology Innovation Organization. “And it isn’t over yet.”
His discussion with a moderator was conducted remotely and recorded for presentation to conference participants. Although he had known that an outbreak like this could occur, one aspect has surprised him, he said, and that is “how rapidly it just took over the planet.”
An efficiently transmitted disease can spread worldwide in six months or a year, but “this took about a month,” Fauci said. He attributed the rapid spread to the contagiousness of the virus, and to extensive world travel by infected people.
Vaccines are widely regarded as the best hope of stopping or at least slowing the pandemic, and Fauci said he was “almost certain” that more than one would be successful. Several are already being tested in people, and at least one is expected to move into large, Phase 3 trials in July.
But much is still unknown about the disease and how it attacks the body, research that Fauci described as “a work in progress.”
New York Times
Brazil obeys order to resume providing full virus data
RIO DE JANEIRO — A Brazilian Supreme Court justice ordered the government of President Jair Bolsonaro to resume publication of full COVID-19 data, including the cumulative death toll, following allegations the government was trying to hide the severity of the pandemic in Latin America’s biggest country.
The government complied with the decision Tuesday afternoon.
Justice Alexandre de Moraes said late Monday that the government is obliged to provide necessary information to Brazilian citizens, days after the Health Ministry scrubbed the cumulative death toll from the new coronavirus from its website.
De Moraes said in his decision that the gravity of the pandemic, which has killed more than 37,000 Brazilians, requires transparency from the government as the country shapes policies to curb the virus.
Brazil’s health ministry stopped publishing the number of total COVID-19 deaths and confirmed coronavirus cases on Friday.
The restriction on the release of data, combined with its announcement after evening news programs had ended, generated widespread criticism. Gilmar Mendes, another Supreme Court justice, said Saturday that manipulation of data is a tactic of authoritarian regimes and that hiding the numbers wouldn’t exempt the government from responsibility for the pandemic’s heavy toll in Brazil.
Facing intense criticism, a top Health Ministry official told reporters Monday night that the ministry would restore the cumulative death toll to its website, but with changes to the methodology for how daily deaths are tallied.
South Asia cases rise at fastest rate across the globe
South Asia coronavirus cases have increased at the fastest rate globally in the past week.
Infections have risen by 27 percent in Pakistan, while Bangladesh cases spiked by 19 percent and 17 percent in India, according to data of the 20 most affected nations compiled by Bloomberg. Pakistan and Bangladesh also had their single-biggest daily spike in fatalities.
As cases dwindle in parts of the United States and Europe, they are still increasing in South America and South Asia. More than 136,000 cases were reported worldwide on Sunday, the most in a single day so far, with nearly 75 percent from 10 countries in the Americas and South Asia, according to WHO Director General Tedros Adhanom Ghebreyesus.
Pakistan crossed 108,000 cases and became the second-largest most infected nation in Asia with about 2,000 deaths. In Bangladesh, the tally surged to 71,675 including 975 deaths, while India has 267,046 cases and 7,473 deaths.
God has ‘removed’ virus, Tanzania’s president claims
NAIROBI — Tanzania’s president is again claiming the country is free of the coronavirus because of the power of prayer — six weeks after his government stopped publicly updating virus data.
‘‘Corona in our country has been removed by the powers of God,’’ President John Magufuli declared at a church service on Sunday. He praised the congregation for not wearing face masks, amid cheers from the faithful. He has warned that masks not approved by the government could be infected with the virus.
Tanzania’s number of COVID-19 cases has been stuck at 509 for six weeks as health officials, opposition figures, and some neighboring countries worry that cases in the East African nation continue to climb. Opposition figures have estimated that cases could be in the tens of thousands.
While many African countries have been praised for their response to the virus, Magufuli believes the pandemic has been greatly exaggerated and is being used by unnamed forces to sabotage the economy.
The president has questioned, even fired, health officials and refused to limit people’s movements, and he has claimed his son was healed of COVID-19 by drinking a mixture of ginger and lemonade.