A new study estimates that 1 in 50 deaths of otherwise healthy children under age 5 around the world is due to a common virus that's currently surging in the U.S. and Canada: , or RSV. And in high-income countries, 1 in 56 babies who are born on time and are healthy will be hospitalized with RSV in the first year of life, according to the researchers' estimates.
The virus is known to be especially dangerous for premature and medically fragile babies, but it causes a "substantial burden of disease in infants worldwide," wrote the authors of the study, published Thursday in the journal Lancet Respiratory Medicine.
Other research has examined the number of children with pre-existing conditions who are hospitalized with RSV, but the new study is one of the first to look at the numbers in otherwise healthy kids.
"This is the lowest-risk baby who is being hospitalized for this, so really, numbers are really much higher than I think some people would have guessed," said study co-author Dr. Louis Bont, a professor of pediatric infectious diseases at Wilhelmina Children's Hospital at University Medical Center Utrecht in the Netherlands. Bont is also the founding chairman of the ReSViNET foundation, a nonprofit dedicated to reducing the global burden of RSV infection.
The estimates are based on a study that looked at the number of RSV cases in 9,154 infants born between July 2017 and April 2020 who were followed for the first year of life. The babies received care at health centers across Europe.
About 1 in 1,000 children in the study were put in an intensive care unit to get help breathing from a mechanical ventilator. This care is vital: In parts of the world where there is a lack of hospital care, the risk of death is significant.
"The vast majority of deaths with RSV occur in developing countries," Bont said. "In the developed world, mortality is really rare, and if it happens, it's virtually only in those who have severe comorbidities. But in most places in the world, there is no intensive care unit."
Globally, RSV is the second leading cause of death during the first year of a child's life, after malaria. Between 100,000 and 200,000 babies die from the virus every year, Bont said.
There are fewer RSV deaths in high-income countries, but the virus still causes substantial morbidity, and even hospitalization can have serious effects, said Dr. Kristina Deeter, chair of pediatrics at the University of Nevada, Reno and a specialty medical officer for pediatric critical care at Pediatrix Medical Group.
"Whether that is just traumatic psychosocial, emotional issues after hospitalization or even having more vulnerable lungs -- you can develop asthma later on, for instance, if you've had a really severe infection at a young age -- it can damage your lungs permanently," said Deeter, who was not involved in the new study. "It's still an important virus in our world and something that we really focus on. It's kind of the bread and butter of a pediatric ICU."
Health-care providers know that November through March is the traditional "viral season," and they must plan accordingly for RSV and other respiratory problems.
Dr. Nicholas Holmes, senior vice president and chief operating officer at Rady Children's Hospital in San Diego, said officials there are always sure to have enough respiratory therapists and physicians to manage the influx of cases.
Even then, at the largest pediatric hospital on the West Coast, officials have had to get creative to keep up with the patient load, Holmes said.
"One thing that we just recently implemented to help is that we have many clinicians who are licensed nurses or therapists, or physicians like myself, who are in nonclinical roles in the organization. So we are engaging those licensed staff back in to help support and bridging that gap to support our nurses, physicians who are in direct line of patient care," Holmes said.
On Wednesday, Holmes said, through the hospital's Helping Hands program, he spent an hour and a half in the emergency department rather than doing his usual work. He checked on families and patients, handing out blankets and fruit pops. It gave him a chance to watch for problems and alert nurses if a child was getting sicker and needed medical attention right away.
"This allows the nursing team in the triage area to really focus on the sickest of the sick kids," Holmes said.
Although there is no specific treatment for RSV in healthy babies, recent developments around vaccines and therapies mean help could be on the way for busy hospitals.
There is only one for patients who have pre-existing conditions or who were born prematurely. It's been available since 1998 and has made a significant difference, Deeter said.
"Once premature babies started to receive that, the numbers drastically dropped," she said. "It is incredibly rare at this point for us to put a baby on a ventilator for RSV. This tiny, fragile group is so well-protected by those injections; however, we still have thousands of babies coming in who didn't receive those injections who still need supportive care, and often, they're managed without a respiratory support system."
There are things parents of infants can do to prevent RSV, said Dr. Priya Soni, an assistant professor of pediatric infectious diseases at Cedars Sinai Medical Center. They're the simple behaviors everyone is familiar with from the Covid-19 pandemic: Thoroughly wash your hands, stay home if you're sick, and keep surfaces clean.
"The virus is a little more hardy on hard surfaces, so really cleaning those surfaces and hand-washing goes a long way with RSV, as well as limiting the child's exposure to infected respiratory secretions and droplets overall," said Soni, who wasn't involved in the new research.
The study's findings about the number of children who get RSV in the first months of life show how important it will be to have an immunization strategy for pregnant women, she said.
"Whatever we could do to close that gap for those young infants that are within the first six months of life, that may be really really prone to that RSV infection, will help," Soni said.
In the U.S., four RSV vaccines may be nearing review by the FDA. Globally, more than a dozen are going through trials. A preventive treatment for lower respiratory tract infections caused by RSV got the go-ahead from the European Commission
These developments can be game-changers, experts say.
"Every pediatrician that I know has always been working very, very hard during Christmastime. We are always swamped with RSV patients every year," Bont said. "This or next year could be the last time that we actually see that, because it could really prevent the bulk of severe infection."
