Alberto Zangrillo, director of the San Raffaele Hospital in Milan, grilled the global public health community on Sunday when he told RAI, the national TV station, that “the virus clinically no longer exists in Italy”, with patients showing small amounts of virus in the nose swabs. Zangrillo theorized in a follow-up interview with The Washington Post that something else might happen “in the interaction between the virus and human respiratory receptors.”
He added, “We cannot show that the virus has mutated, but we cannot ignore that our clinical results have improved dramatically.”
The comments, which received a lot of attention after a Reuters report, prompted a strong pushback from Michael Ryan, a senior official at the World Health Organization, who said on Monday during an online conference that “we have to be exceptionally careful not to create a sense of having suddenly the virus of its own will now decided to be less pathogenic. That is not the case at all. “
Consensus among other experts interviewed on Monday is that the clinical results in Italy probably do not reflect any change in the virus itself.
Zangrillo’s clinical observations are more likely to reflect the fact that, with the onset of the outbreak, it has less virus in circulation, and people may be less likely to be exposed to high doses of it. In addition, only severely ill people were tested early compared to the situation now when even those with mild symptoms are more likely to become tense, experts said.
The pandemic is developing rapidly, with the number of new cases decreasing in some severely affected areas of the world, including northern Italy and New York City, while rising dramatically in Brazil, Peru and India. However, the virus is slowly mutating, experts say.
Some strains of the virus have become more dominant, but there is no solid evidence yet that any of them are more infectious or deadly, according to researchers who have reviewed recent genetic studies.
Vaughn Cooper, an expert on infectious diseases at the University of Pittsburgh School of Medicine, said the new coronavirus is mutating slowly compared to influenza and other microbes, and its genetic changes appear to be “mostly insignificant.”
“I think it is safe to say that the differences that doctors report in Italy are entirely due to changes in medical treatment and in human behavior, which limits the transmission and number of new infections initiated by large inocula – a larger dose of virus appears to be worse – rather than changes in the virus itself, ”he said.
All viruses develop over time and many infectious disease experts believe that the new coronavirus will eventually become less fatal to humans and will join four other coronaviruses to cause colds. But there is no firm evidence to date that it has changed significantly in the five months since it was first recognized among patients in Wuhan, China.
“The virus has not lost function on the time scale of two months,” said Andrew Noymer, an epidemiologist at the University of California at Irvine. “Functional loss is something I expect over a time scale of years.”
In the United States, the pandemic has received a patchwork pattern, where large parts of the northeast have shown a marked improvement. But some locations in the South – Alabama, Texas and Virginia, for example – as well as the state of Wisconsin, California and Washington show increases in confirmed cases, according to coronavirus tracker from Johns Hopkins University.
“Each site has a different epidemic, and it’s not because of the virus,” said Jennifer Nuzzo, an epidemiologist at the Johns Hopkins Center for Health Security.
A few tweaks in the microbe’s genetic makeup appear at various places on the planet. Epidemiologists use these mutations to track the spread of the virus. These changes are similar to stickers that are dropped on a traveling suitcase – markers for where your luggage has gone that do not provide any functional change.
Researchers Harm van Bakel, Emilia Sordillo and Viviana Simon at Icahn School of Medicine at Mount Sinai, who have focused on genetics for the new coronavirus, said in an interview that they had not seen a dip in viral load among patients in the hospital system since March, and they have also not detected any major genetic changes in the virus in New York City.
People in the United States collectively hold their breath, to see if there is an upward trend in cases in response to the economy’s resumption, public gatherings over public holidays and the outbreak of police violence in recent days.
Nuzzo pointed out that it usually takes about five days, and up to 14 days, for an infection to result in symptoms, and then there is an additional time delay before anyone seeks a test and gets a result. There is also a delay between when the symptoms begin and a person with a serious illness needs hospitalization. Thus, it may be several weeks before the decrease in social distance can lead to a detectable change in the path of a local epidemic, she said.
The confusion of uncertainty is the lack of a clear understanding of where and how the virus spreads, as the country has not made the extensive test and contact tracking to know where or how infections have occurred.
“We never knew where the transfer was in the United States. And still don’t know, she said. “Is it risky to go to the grocery store?”
Caitlin Rivers, an epidemiologist and senior researcher at Johns Hopkins, noted that it is difficult to know the extent to which people exercise recommended safety measures, such as social distance, in communities that have facilitated home-at-home orders. She is most concerned about tight institutions where social distance is difficult or impossible.
“I think we will continue to see explosive outbreaks associated with institutions,” Rivers said.
Of the ten counties in the United States that are experiencing the largest increase in their seven-day new case on average from Friday, May 22 to Friday, May 29, at least nine have experienced outbreaks at a prison facility, detention center, food processing center, or health care facility.
“An outbreak starts at an institution, then it starts moving into the community,” Rivers said. “We can’t just say, ‘It’s there, it’s irrelevant to the rest of us.’ It’s not true. ‘