Omicron sickens people faster
Experts advise forgoing crowded New Year’s revelry
This would be a good New Year’s to spend at home.
Omicron makes people sick faster than earlier variants, according to a study released Tuesday by the Centers for Disease Control and Prevention.
Although most cases of omicron appear to be relatively mild, people generally get COVID-19 symptoms three days after being exposed to the virus, rather than about four days with delta and five or longer with the original virus, the study concludes.
People are probably contagious sooner after exposure – and maybe even before they test positive for infection.
Jacob Lemieux, an infectious disease expert at Massachusetts General Hospital, recommended saving new year parties for later.
“The thing to do is to postpone when the force of infection is so high and look for a time in the future when it’s safer to do these things,” he said. “In a few weeks, the situation may be substantially better.”
Cases have been rising sharply since Thanksgiving, according to the CDC, and more than 85% of U.S. counties meet criteria for “high” COVID-19 transmission, analysis of Johns Hopkins University data shows.
The new CDC study focused on a family in Nebraska, reinfected with omicron after catching COVID-19 last year. One of the five family members was vaccinated. All five had similar or milder symptoms with their new infections, the study found.
It’s not clear if the family members were reinfected because their immunity faded over the year between infections, if omicron is better at getting around immunity from infections or both.
Question: How does omicron affect children?
Answer: It’s still unclear if omicron is more likely to make children sick than earlier variants. Children under 5 are
not eligible for vaccination. “We keep seeing upticks in kids,” perhaps because they’re unvaccinated, said Pardis Sabeti, a computational geneticist. “We should protect those who can’t protect themselves, because we don’t know what a virus can do.”
Texas Children’s Hospital follows children to see if omicron affects them differently than previous variants or if there are different risk factors for severe disease, said James Versalovic, the hospital’s pathologist in chief. Staff will gather data on the vaccination status of children hospitalized with COVID-19.
“We will be watching and monitoring during the days and weeks ahead with the new variant,” he said. “At this point, we just expect to see more of the same.”
Q: How soon after exposure can a test determine if I’m contagious?
A: How quickly people will be contagious after infection is tough to predict, said Sabeti, who works for the Broad Institute of MIT and Harvard, a genetics research center. It depends on an individual’s viral load as well as the variant.
Omicron moves so quickly, she said, that it’s possible to test negative in the morning but be positive by the afternoon or evening. “I don’t feel as if we know enough about the exact dynamics
of when you test positive and how likely you are to then spread it,” she said. Diagnostic tests are helpful, but they’re not foolproof.
The best way to ensure protection, she said, is by layering protection: testing, masking and getting vaccinated.
There is an association between having symptoms and being contagious, Sabeti said, but it’s not a perfect correlation. “We’ve seen plenty of people who are completely unaware, asymptomatic, but with screaming viral loads,” she said. “And we’ve seen people who are symptomatic with very low viral loads.”
Q: What kind of tests can I get?
A: Molecular PCR tests, often administered at clinics, doctors’ offices, hospitals or large-scale testing sites, are more sensitive and can detect traces of the virus over a longer period during the course of an infection. These tests often require medical oversight, typically deliver results in a day or two and are more expensive, often costing $100 or more per test.
Rapid antigen tests can be taken at home, typically deliver results in about 15 minutes and don’t require a lab.
Q: Are home tests hard to find?
A: The two largest manufacturers, Abbott and Quidel, slowed production this spring as coronavirus cases dropped. The manufacturing cutbacks followed a CDC recommendation that vaccinated people did not need to get tested. The CDC reversed its guideline as more breakthrough cases emerged.
Home test shortages surfaced this summer when the delta variant increased cases and more people sought testing. Although the Food and Drug Administration gave emergency use authorization to more than a dozen home test manufacturers, home tests are frequently sold out at major retailers.
Q: How sick am I likely to get if infected?
A: Omicron appears to cause less severe disease than earlier variants, particularly among people who have been vaccinated or previously infected.
But it’s also causing more “breakthrough” infections in those who thought they were protected by vaccination or infection, and people with weakened immune systems remain at extra risk.
Q: What if I’m traveling or going out for New Year’s?
A: Because omicron spreads so quickly and efficiently, the odds are greater that you will come into contact with the virus. If you are committed to attending a gathering, get vaccinated and boosted and encourage friends and family to do the same.
“That’s probably not going to prevent people from getting this virus, but I would much rather have a mild cold than be worried about prospects of going to a hospital,” said Jennifer Nuzzo, an epidemiologist and senior scholar at the Johns Hopkins Center for Health Security.
Boosters usually take at least a week to provide protection, and the first doses, separated by three or four weeks, take about six weeks to reach full protection.
Experts recommend people get tested right before a gathering instead of a few days beforehand. One example might be to administer rapid tests in a car before entering someone’s house. Although home antigen tests are not perfect, “perfect is not the goal. We need everyone to be a bit better,” Nuzzo said.