Nov 14, 2023
A new COVID variant, HV.1, is now dominant. These are its most common symptoms
A highly contagious new COVID-19 variant called HV.1 is spreading rapidly across the United States.
HV.1, which is a subvariant of omicron, is now the dominant strain in the country, according to the the U.S. Centers for Disease Control and Prevention.
Scientists have been tracking HV.1 since the summer, when it was circulating at relatively low levels. In October, HV.1 quickly gained speed and overtook other variants, including EG.5, aka Eris, to become the most prevalent strain.
Currently, HV.1 is responsible for nearly one-third of all COVID-19 cases in the U.S., per the CDC. The variant's rise to dominance comes as the country enters respiratory virus season and health officials roll out updated COVID-19 vaccines ahead of a potential winter surge.
According to the CDC, HV.1 accounted for an estimated 29% of new COVID-19 cases during the two-week period ending Nov. 11. After HV.1, the next most common variant in the U.S. was EG.5, which made up just under 22% of cases, followed by FL.1.5.1 or “Fornax,” and XBB.1.16 or “Arcturus.” (EG.5 is still the dominant strain worldwide, according to the World Health Organization.)
All of the most prevalent COVID-19 strains in the U.S. are offshoots of omicron, which first emerged in November 2021. The SARS-CoV-2 virus, which causes COVID-19, is able to mutate and give rise to new, highly contagious variants.
However, health experts say there's no reason to panic about this new COVID variant.
After a late summer surge, COVID-19 cases and hospitalizations have been trending downward in recent weeks, according to CDC data. Additionally, the updated COVID-19 booster still offers protection against newer variants — although uptake has been very low so far, TODAY.com previously reported.
Infections are expected to increase again this winter as was the case the past three winter seasons, Dr. William Schaffner, professor of infectious diseases at Vanderbilt University Medical Center, tells TODAY.com.
As HV.1 spreads, many are curious if the new subvariant is more contagious or severe, whether it could cause different symptoms, and when they should get the new COVID-19 booster. Here’s what we know about HV.1 so far.
What is HV.1, the new COVID variant?
HV.1 is part of the omicron family. “You can almost think of HV.1 as a grandchild of omicron,” says Schaffner. HV.1 is a sublineage of omicron XBB.1.9.2 and a direct descendent of EG.5, according to the CDC's SARS-CoV-2 lineage tree.
“The COVID family of viruses likes to mutate. We’ve all learned that by now," says Schaffner. While HV.1 is mutated, it's still very close to the existing omicron subvariants, Schaffner explains.
For the most part, scientists are not concerned about new variants like HV.1, which look very similar to strains we've already seen before, NBC News reported.
However, there are a few highly mutated strains which have set off alarm bells. These include BA.2.86 or Pirola, which has an extra 36 mutations that differentiate it from XBB.1.5., and a newer variant called JN.1, which has one more mutation than Pirola.
Fortunately, neither BA.2.86 nor JN.1 are common in the U.S. right now, according to the CDC — JN.1 is so rare that it makes up fewer than 0.1% of SARS-CoV-2 cases.
As for HV.1, it rapidly gained steam after it was first detected this past summer. In late July, HV.1 accounted for just 0.5% of COVID-19 cases in the U.S., CDC data show. By Sept. 30, HV.1 made up 12.5% of cases, and by November, it was the dominant strain.
Is HV.1 more transmissible?
“One of the characteristics of this entire omicron family is that they are highly transmissible," says Schaffner. Sometimes, mutations can enable a new variant to spread more effectively or quickly, per the CDC.
Right now, it appears that HV.1 could be slightly better at spreading from person to person than previous strains, NBC News reported. The increased transmissibility of HV.1 likely explains how it became dominant so quickly in the U.S., Schaffner notes.
It appears that HV.1 could also be slightly better at escaping prior immunity to COVID-19, but not enough to cause alarm, Dr. Dan Barouch, director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center in Boston, told NBC News.
Although it is more transmissible, HV.1 does not appear to produce more severe disease or lead to more hospitalizations, Schaffer says.
What are HV.1 symptoms?
The symptoms caused by infection with HV.1 are similar to those caused by recent variants, says Schaffner, which include:
Congestion or stuffiness
Fever or chills
“Congestion, sore throat and dry cough seem to be the three most prominent symptoms right now,” says Schaffner.
Increasingly, doctors report that COVID-19 symptoms appear to follow a pattern of being concentrated in the upper respiratory tract, starting with a sore throat and followed by congestion or a runny nose, NBC news reported.
Coughing isn't typically a primary symptom, but it can persist. "The virus seems to produce a kind of a chronic bronchitis, so that you can have a cough syndrome that lasts beyond the period where you’ve recovered from other symptoms," says Schaffner.
Another trend is that COVID-19 seems to be causing milder infections, likely because people have some prior immunity. “By milder, we mean it doesn’t require hospitalization even though you can feel quite miserable for several days,” says Schaffner.
Do COVID-19 tests detect HV.1?
All COVID-19 tests — including PCR tests performed by a health care provider and rapid at-home antigen tests — will detect HV.1, says Schaffner.
Testing is a crucial tool to protect yourself and others from COVID-19. The symptoms of HV.1 and other COVID-19 variants can look very similar to other viruses, including respiratory syncytial virus (RSV), influenza and rhinovirus, which usually causes the common cold.
"The only way to distinguish (COVID-19) from RSV and flu, both of which are now gaining steam, is by testing," says Schaffner.
Experts encourage anyone who has symptoms to get tested, especially those in high-risk groups — people over the age of 65, who are immunocompromised or who have underlying health conditions.
“We have treatments that can prevent more serious disease," says Schaffner, but early detection is key. COVID-19 antivirals such as Paxlovid are effective against HV.1 and other variants, but they work best when within five days of symptom onset, TODAY.com previously reported.
Testing has significantly diminished in the U.S. in the last year, which is concerning, says Schaffner.
When the U.S. federal public health emergency for COVID-19 ended in May, so did the guarantee of free testing for many people.
However, every American can still get COVID-19 tests for free or low-cost right now. One way is to order four free at-home COVID-19 tests from the government, which will be delivered by mail via the U.S. Postal Service. To order your free tests, go to COVIDTests.gov.
In addition, all health insurance plans are required to reimburse eight at-home COVID-19 tests per month, according to the Centers for Medicare & Medicaid Services. State Medicaid programs are also required to cover at-home tests, and Medicare beneficiaries and uninsured individuals can access free tests provided by Health & Human Services at thousands of community health centers, clinics and pharmacies.
If you still have a stockpile of tests sitting around, remember to check the expiration date and whether it's been extended by the U.S. Food and Drug Administration.
Does the new COVID-19 vaccine protect against HV.1?
The updated COVID-19 vaccine is recommended by the CDC for everyone ages 6 months and older. It is now widely available at pharmacies, doctor's offices and other locations around the U.S., says Schaffner.
The new boosters have been reformulated to target omicron XBB.1.5, which was the dominant COVID variant for most of 2023. While XBB.1.5 has since been overtaken by HV.1, Eris, Fornax and Arcturus, it is still closely related to these newer strains.
The updated vaccines seem to be well-matched to the variants currently circulating and making people sick, Andrew Pekosz, Ph.D., virologist at Johns Hopkins University, previously told TODAY.com.
“Laboratory studies indicate that the updated booster will protect against serious disease caused by HV.1,” says Schaffner. Vaccination also significantly lowers the risk of becoming hospitalized or dying, per the CDC.
However, only 23 million Americans or 4.5% of the population had received the updated shots by Oct. 27, Reuters reported.
The first phase of the new booster rollout hit several speed bumps, including supply delays, high demand, cancelled appointments and insurance obstacles. Some parents have been unable to get their kids vaccinated as some pharmacies and pediatrician's offices have struggled to secure enough child-size doses.
Although many of these initial issues have been resolved, says Schaffner, uptake is still slow. "We've underutilized this updated vaccine, and we anticipate that COVID will once again increase even more during the winter season," says Schaffner.
It's not too late to take advantage of the new booster, Schaffner adds, and people should get the shot as soon as they can.
The FDA has authorized three vaccine options for 2023-2024: one mRNA shot each from Moderna and Pfizer, and a protein-based non-mRNA shot from Novavax.
Insurance plans should cover the updated booster, says Schaffner, and those without insurance should still be able to get the shot for free, according to the CDC.
“We’re in a good place because for a considerable time now, we have not had a new variant that causes more severe disease or evades the protection of currently available vaccines,” says Schaffner.
How to protect yourself from HV.1
As the winter and holiday season approaches, it's important to take steps to protect yourself from COVID-19 and prevent transmission to others, especially the most vulnerable. These include:
Staying up to date with COVID-19 vaccines
Getting tested if you have symptoms
Isolating if you are testing positive for COVID-19
Avoiding contact with sick people
Improving ventilation or gathering outdoors
Washing your hands with soap and water frequently
Wearing a mask in crowded, indoor spaces
This article was originally published on TODAY.com