As respiratory syncytial virusotherwise known as RSV, continues to surge in the United States, experts warn that it is possible for people to become infected with it more than once.
Dr. Aaron Glatt, chief of infectious diseases at Mount Sinai South Nassau Hospital on Long Island, New York, told Fox News Digital this week, “A person can get RSV more than once in their lifetime.”
A second infection is unlikely to occur immediately after a recent episode. Yet it can infect someone more than once in the same season, especially immunocompromised children and older adults, Glatt said.
“Weekly rates of RSV hospitalizations are currently much higher than they have been in the previous four seasons, exceeding peak weekly rates in all pediatric age groups since pediatric data were released. started being collected in RSV-NET in October 2018,” a spokesperson for the centers said. for Disease Control and Prevention (CDC) told Fox News Digital.
RSV-NET reports surveillance of recent laboratory-confirmed RSV-associated hospitalizations in children under 18 years of age, as well as adults.
“The timing is also unusual because we don’t typically see such high hospitalization rates in October and November,” the CDC spokesperson also said.
“Rates are higher now than they were even compared to the fall of 2021, when there was an unusual RSV circulation pattern.”
“Certainly RSV is normally seen in winter, so weather plays a critical role and in its endemicity,” added Glatt, also a spokesperson for the Infectious Diseases Society of America.
“But if RSV is where you are, you can catch it in any weather, even though it’s really a winter disease,” he said.
Why are we seeing an increase in cases?
“Before 2020, seasonal RSV trends in the United States were very consistent,” the CDC noted on its website.
“However, the circulation patterns of RSV and other common respiratory viruses have been disrupted since the onset of the Covid-19 pandemic early 2020,” the agency added.
“The CDC is now releasing weekly hospitalization rates for laboratory-confirmed RSV hospitalizations, as determined by the RSV-NET sentinel surveillance system,” a CDC spokesperson told Fox News Digital.
RSV hospitalization rates are highest in children [who are less than] six months, but hospitalization rates have also increased among older children compared to previous seasons.”
Many people focus on those at high risk for RSV, such as premature infants, young children with heart defects at birth and chronic lung disease – or those who have depressed immune systems.
“About two-thirds of children who are admitted with RSV are actually normal, healthy children.”
But those patients account for only a third of hospitalizations, said Dr. James H. Conway, a pediatric infectious disease physician and medical director of the immunization program at UW Health Kids in Madison, Wisconsin.
“About two-thirds of children who are admitted with RSV are actually normal, healthy children,” said Conway, who is also a professor of pediatrics at the University of Wisconsin School of Medicine and Public Health. .
Hospitalization rates for RSV in adults have also increased, “with the highest adult hospitalization rates occurring in those 65 and older,” a CDC spokesperson said.
The data, however, should be interpreted with caution, as the last two weeks of RSV-NET data are subject to lag in reporting.
Why are some people infected more than once?
“We’ve known for decades that for most respiratory viruses — whether rhinovirus, parainfluenza virus, or RSV — immunity against natural respiratory viruses just isn’t great,” Conway noted. .
“That’s why people can get these infections over and over again.”
And like the flu, people can be infected with different strains of RSV.
“Similar to the flu, there are several strains of RSV, so there is RSV-A [strain] and there is an RSV-B [strain] – as there is the flu [type] A and flu [type] B,” Conway told Fox News Digital.
“People can get it multiple times because even if they have one type, the cross-protective immunity is only partial.”
It is often difficult to prevent an infection once the virus has already invaded the body.
Our immunity has several components, including different types of antibodies — circulating antibodies that patrol our bloodstream for foreign invaders and secretory antibodies, Conway said.
“There are parts of your immune system that are basically responsible for grabbing [the virus and] saying: ‘It’s important’ [to] present to your immune system’ and ‘It’s something we really have to deal with.'”
However, it is often difficult to prevent an infection once the virus has already invaded the body, he added.
The next time the person is exposed to the virus, the immune system remembers and “aligns” its arsenal of T cells to neutralize the virus.
“But as a temporary measure, [the immune system] takes your B cells and activates a bunch of antibodies that will go around grabbing those viruses to get them out of that circulation [perhaps] before they cause disease,” Conway noted.
Possible vaccines for the elderly
Conway noted that by next fall we could have our first RSV vaccines for the elderly in the United States.
Several companies, including Pfizer, GSK and Janssen, have RSV vaccines in the final stages of human trials for adults, namely the elderly, according to multiple reports.
“Baby protection in the form of monoclonal antibody injections is already available for high-risk preterm infants, and long-acting versions for all children are also on the horizon,” Conway added.