Can omicron spread have a positive?
0:42
(CNN) -
The first reports of the rapid spread of the omicron variant in South Africa were frightening at first, but then began to offer some hope.
The new variant may have quickly outpaced other strains in South Africa as it entered the summer, but the cases so far appear to have been mostly mild.
Then came a report showing that the variant carries a piece of genetic material that is very similar to the segments seen in one of the types of coronaviruses that cause common colds, one called HCoV-229E.
Some researchers said it could indicate that the variant is starting to look more like a pesky virus than a big killer.
It is a tempting idea.
Many infectious disease experts have been predicting that the new coronavirus, called SARS-CoV-2, would go in this direction, evolving into a milder form that joins the annual mix of seasonal respiratory viruses.
Could this be the variant that at least starts that path?
It's too early to start thinking that, several experts told CNN.
On the one hand, that segment of genetic material may look like a fragment of the common cold virus, but it's a long way to say from there that that means SARS-CoV-2 has started to evolve into something milder.
advertising
"Even assuming the insert came from a common cold virus, that's very dangerous, it probably wouldn't make it more like the common cold virus," virologist Robert Garry of Tulane University School of Medicine told CNN. .
Tshwane, the epicenter of omicron in the sights of scientists 1:09
It is a small piece of genetic material and not necessarily a part of the virus that would affect its virulence, Garry said.
"The idea that this variant is milder is pure speculation. There's no reason to think it is," said Michael Worobey, who heads the Department of Evolutionary Biology at the University of Arizona.
It takes time to develop a serious illness
Furthermore, there has not been enough time to state that real-world experience with omicron shows that it primarily causes mild illness.
It takes between two days and two weeks to develop symptoms after exposure to the coronavirus, according to the US Centers for Disease Control and Prevention.
There hasn't been enough time to know how likely omicron is to cause serious illness, said Dr. William Schaffner, medical director of the National Infectious Disease Foundation and an infectious disease expert at Vanderbilt University.
"There is a distinction between hope and reality. It is good to have hope, but it is too early to conclude that omicron only causes mild infections. We do not have that data," Schaffner told CNN.
"Covid-19 has thrown us several curve balls."
Data from South Africa, the first country to detect the omicron variant, looks encouraging.
This is the search for the omicron variant in the US 2:38
"We are not seeing many serious cases. I want to warn that we have only known about this for a week, so it is early," Dr. Salim Abdool Karim, an infectious disease epidemiologist who is helping coordinate South Africa's response to the covid-19.
"I've been talking to the president of our medical association. She collects this data from all doctors, and essentially what they are telling us at this stage is that the cases are generally mild," he added.
"Now, you have to be very careful about overinterpreting that, because it's still too early, as severe cases usually take longer. They occur in weeks two, three, and four. So it may be that severe cases come later." .
Schaffner puts it a little more bluntly.
"Death is a lagging indicator," he said.
"It takes time to progress to a serious infection. It takes time for more serious infections to follow," he said.
Different populations in different countries
Dr. Amesh Adalja, principal investigator at the Johns Hopkins Center for Health Safety at the Bloomberg School of Public Health, said he hopes early reports indicate that omicron could cause milder illness.
"There is a possibility that maybe this is not as bad as some feared," Adalja told CNN.
"That does not mean that it is not bad at all," he added.
"The caveat is that South Africa has a younger population."
Younger people have been less likely to develop a serious illness from Covid-19, which has already killed 5.2 million people worldwide and 789,000 in the United States alone, according to Johns Hopkins University.
But more people are vaccinated in the United States than in South Africa.
Vaccine studies against omicron are underway.
"I think it is quite easy to say that if you are fully vaccinated, the reinfection that you will get with omicron will be milder," Adalja said.
"Even if this avoids some of our vaccine-induced protection, it is not an all or fact effect."
And it is becoming apparent that omicron is highly transmittable.
"Over the past week, the number of daily infections has increased fivefold," South African President Cyril Ramaphosa said in a weekly bulletin on Monday.
The rate of positive tests for covid-19 in South Africa has risen 24% since the omicron variant was detected two weeks ago, according to the latest data from the South African National Institute of Communicable Diseases.
The omicron variant advances in America 0:43
A virus that is more transmissible and causes milder illness is just what scientists would expect to see in something that was evolving to look more like other common cold viruses.
"Those of us who know that this is going to be an endemic respiratory virus have been waiting to understand what the virus does to become more like the other members of the family that cause about 25% of our common colds. So the people are attentive to these changes. And maybe this is it, maybe it is not, "said Adalja.
Delta, the 'old enemy' is still dominant
Also, it's not clear that omicron can compete with delta in countries like the United States, said Dr. Crystal Watson of Johns Hopkins.
"Even if we have good protection against serious illness and death from vaccines, a large increase in omicron could be dangerous if it is highly communicable," said Watson, a senior associate at the Johns Hopkins Center for Health Safety.
"High numbers can still mean a lot of people in the hospital," he said.
"There will be some people, a population large enough to create stress on the health system, who will not be as protected by vaccination or previous infection."
That could put more pressure on hospitals that are already stressed.
"Our health care system is so fragile right now," Watson said.
"We have lost a lot of staff and people are really exhausted. The system itself is exhausted."
That's the same all over the world, said Francois Balloux, director of the University College London Genetics Institute.
"Preliminary evidence, largely anecdotal, suggests that omicron may be less virulent than delta. This would be good news if confirmed, in principle," Balloux said in a statement.
"It remains that even if omicron infections were associated with fewer hospitalizations and deaths, a small fraction of the serious outcomes from a large number of infections could still put intense strain on healthcare systems."
Cases of omicron seem mild, according to authorities in Asia-Pacific 0:52
And Schaffner worries that unvaccinated people might take reports of a milder variant as a reason to keep putting off vaccination.
"While we are concerned and fascinated by omicron, delta, the old enemy of summer is still here causing damage," he said.
"We all have to get vaccinated. All this omicron spell is not an excuse not to get vaccinated."
CNN's Niamh Kennedy, Larry Madowo, Wayne Chang, and Naomi Thomas contributed to this report.
omicron