RSV has many of the same symptoms of other respiratory infections: runny nose, decreased appetite, coughing, sneezing, fever and wheezing. Nearly all children get infected at some time in their childhoods. Most children and adults who have it have mild illness, but it can cause major complications in very young children and some adults, physicians said.
Dr. Sarah Rudman, Santa Clara County deputy health officer, said the county is seeing a large uptick in cases that are stretching hospital capacity.
"We're hearing that hospital pediatric care is starting to feel the burden of RSV in young children. The hospitals are at, or near, full capacity and are starting to think about transferring patients" or expanding their care units, she said.
"It's clear that our winter respiratory illness cases are looking worse, and even worse than pre-pandemic," she said.
The situation also is compounded by influenza and COVID-19. This may be the first year that hospitals have to contend with all three, she said.
Wastewater surveillance through the Stanford SCAN system, which tracks the presence of disease genetic material in sewage, also is showing a steep rise in the presence of RSV.
In an email, the County of Santa Clara Health System stated that its three public hospitals, Santa Clara Valley Medical Center (SCVMC), O'Connor Hospital and St. Louise Regional Hospital, reported treating approximately 300 RSV cases from this past September through October, versus only 20 last year at the same time. There currently are no cases of adults hospitalized with RSV at Valley Medical.
"Some of these patients have been seen in our three emergency departments, but patients were also treated at our Pediatric Acute Care clinic and other urgent care clinics. Eight RSV-positive pediatric patients are currently admitted to SCVMC for treatment, all younger than 5 years old. Most of these currently admitted patients have a diagnosis of bronchiolitis, which is inflammation of the small airways of the lungs."
RSV, although it has many of the same symptoms as other respiratory diseases, can be particularly dangerous for infants.
"The reason why RSV and some of these other viruses can get babies into trouble is that their airways and their lungs are so small that if you get some mucus buildup and swelling in those small airways it makes it very hard for babies to breathe. For older people, older children and adults because the airways are bigger, we tend not to see nearly as much trouble with these viruses. That being said, certain patients — older patients who are immunocompromised or have chronic medical illnesses — may be quite susceptible to getting sick from RSV and other viruses," Dr. Alan Schroeder, a critical care physician at Stanford Medicine Children's Health, said.
RSV is likely dominating and causing many children to end up in the emergency department at Lucile Packard Children's Hospital Stanford because people have dropped cautionary practices that were in place during the earlier phases of the COVID-19 pandemic. With less immunity built up in the population, more people are vulnerable, he said.
About half of the overall cases at Stanford Medicine Children's Health are from RSV, Schroeder said. COVID-19 cases are causing about 10% of the overall cases being seen. Influenza cases also are about 10% of cases at Packard Hospital.
RSV and influenza are also starting earlier than in past years.
"Normally our busiest winter months from a virus perspective tend to be January and February. We may start seeing some cases in December or even a little bit in November, but we've been busy with viruses really, starting in early October," he said.
Partnerships with a number of regional hospitals has enabled Packard Hospital to send children to some of these other hospitals and conversely, to receive children when there are overflows. "We've certainly been doing that," he said.
Packard hasn't had the high-stress levels of other facilities.
"Orange County just declared a state of emergency. We're hearing about Chicago, Connecticut, elsewhere where (patients) are having to go hundreds of miles to be hospitalized. And we haven't quite gotten to that level yet," he said.
The hospital does have some very high-capacity days in its emergency room. "We're having to be creative about getting the care that (patients) need, but we're able to do it safely," he said.
Dr. Darvin Scott Smith, chief of infectious diseases at Kaiser Permanente in Redwood City, said there is a rise in RSV cases in the community but last week it leveled off a bit.
"That's kind of the story across the country as well with respect to pace numbers. And mainly it's in kids. Of course, that's where we observe it. But it has gone up week over week for the last six weeks," he said.
Kaiser does have the capacity to manage the cases the hospital is observing, he said.
RSV has symptoms that are virtually indistinguishable from other respiratory viruses, so unless one is testing for it, they wouldn't know it's RSV, he said.
Parents should seek medical intervention if the child has severe wheezing or rapid breathing, if they change color, or are blue or have blue lips, Smith said..
"Those are obvious things. You have to be aware of it and looking for it, but decreased uptake or intake of fluids and food, just extreme lethargy, tiredness, dehydration that might be picked up in a young kid with dry diapers repeatedly. Those kinds of things are what to look out for," he said.
Besides the usual precautions of hand washing and limiting contact with people who are ill, Smith said that the best strategy to avoid complications is vaccination against the other viruses known to be circulating at the same time: influenza and COVID-19.
"It's a clear and well-known step to take in order to mitigate that risk. We advocate with great enthusiasm getting fully vaccinated, especially against three things: COVID, influenza, and now we have a new Pneumovax vaccine against a variety of strains of pneumonia. The CDC is advocating for people with risk categories to get all of those things. Those vaccines will really help to decrease RSV and other respiratory virus risks," he said.
A vaccine against RSV is coming, Smith said. "There have been announcements about it by a couple of different companies. So it is in the pipeline and it might be here within a year or so," he said.