Hospitals seeing 'exponential' rise in flu cases in Western Pa.

After a holiday season filled with travel, family gatherings and relatives breathing on each other, respiratory illnesses are on the rise in Western Pennsylvania — with flu cases spiking the fastest.

Area hospitals are seeing an “exponential increase” in flu diagnoses, said Dr. Graham Snyder, medical director of infection prevention and hospital epidemiology at UPMC.

Those numbers are expected to rise over the next few weeks.

“There is no indication yet that we have reached a ‘peak,’” said Snyder.

Allegheny County saw nearly 1,100 flu cases during the week ending Dec. 24, a jump of about 400 cases from the previous week, according to data from the Allegheny County Health Department. Flu cases increased by about 200 between the week ending Dec. 17 and the week ending Dec. 10. Westmoreland County does not track weekly flu statistics.

Between Oct. 2 and Dec. 30 in Allegheny County, there have been 4,883 cases of flu and 1,990 cases of RSV, according to the state Department of Health’s website. In Westmoreland County, there have been 1,904 cases of flu and 509 cases of RSV.

It’s a great unknown whether this season’s weekly pace of new flu cases will reach last year’s, which topped out at 2,000 during the last week of November.

At this time last year, Allegheny County had logged just under 14,000 cases. The county has only registered about one-third of last year’s total so far, but there’s ample room for that tally to grow with the peak likely still ahead.

Flu cases have been increasing across the country, and despite the recent spike and countless anecdotes of flu and other respiratory illnesses canceling holiday plans, experts aren’t hitting the panic button.

Dr. Amesh Adalja, a Pittsburgh-based infectious disease specialist for Johns Hopkins Center for Health Security, said it’s not clear if flu cases have topped out in the area. He said the amount of cases are not unusual.

This season’s flu cases are tracking closely with the 2019-2020 season, which hit its zenith at about 1,300 cases the week of New Year’s Day.

“The numbers are in line with what I expected in a normal respiratory season, especially when covid is integrated into it,” Adalja said.

Rising respiratory cases

If you’re not getting over a cough, you probably know someone who is. Pennsylvania has a high level of covid-19, influenza and RSV activity, according to the national Centers for Disease Control and Prevention.

The count of covid-19 cases jumped as well, to 1,084 in the week ending Dec. 24, up from 830 a week earlier. That rise mirrored trends from last year. RSV cases have remained more stable, hovering between 200 and 300 per week since mid-November. An increase could be ahead, according to the Allegheny County Health Department, which said the virus is getting a later start compared to last year.

Snyder said rising cases have not translated to an increase in the severity of covid, the flu, or RSV.

“The shape of this year’s influenza and RSV epidemics are a little different than last year, when both influenza and RSV emerged earlier than typical for these viruses,” he said. “But this year, so far, these viruses are spreading similarly to pre-covid-19 pandemic.”

Adalja said there is no data showing symptoms from these viruses are any worse than would be expected, and hospitalization rates indicated the cases are “manageable and not out of the ordinary.”

Hospitals in some parts of the country have reinstituted mask mandates during the spike. UPMC hospitals restarted mandatory masking on Dec. 20, but other area hospitals have held off.

Dr. Brian Parker, Allegheny Health Network’s chief quality and learning officer, said that AHN is monitoring data and doing daily evaluations about whether to bring back mandatory masking.

Vaccine ‘Complacency’

During this increase in respiratory illnesses, doctors are reminding patients of the virtues of a regular vaccination regimen. They said covid cases, which have also been increasing, are now a typical part of the winter illness season.

The best way to fight off the flu, covid, and RSV are to be up to date on vaccines.

About 43% of eligible adults are vaccinated for flu this season in Pennsylvania, just marginally higher than the national average, according to Dec. 9 data from the CDC.

In 2022, about half of eligible Pennsylvanians received a flu vaccine.

Adalja said getting the majority of the eligible population to take the flu vaccine has consistently been a struggle.

“Complacency is a major factor and always has been with flu vaccines,” he said.

The Allegheny County Health Department did not have county-level vaccine data. It referred inquiries to the state Department of Health, which did not respond to repeated requests for comment Thursday.

The health department has not provided county-level vaccine updates since September.

CDC data shows 20% of Pennsylvanians are up to date on covid vaccinations, slightly higher than national average. Those rates have increased from only 3% in September, which was when the new covid vaccines became widely available. Vaccination levels appear to have leveled off in December.

Up-to-date covid vaccine rates for the latest variant are in line with vaccine booster rates from 2022, but they are significantly down from the initial vaccination rates of 2021. The New York Times reported that 74% of Pennsylvanians received their completed covid vaccine series in 2021.

Adalja said people should be, at the very least, treating seasonal covid vaccines like they treat the flu. Covid vaccine rates are about half of flu vaccine rates in Pennsylvania.

“For covid vaccines it is important for high-risk individuals to stay up to date, and everyone should be getting a flu vaccine,” he said. “These are important tools that make these illnesses more manageable both individually and on a societal level.”

Snyder of UPMC agrees.

“The covid-19 vaccination strategy is now similar to influenza — each season we will have vaccines that will prepare us for the changing viruses that are anticipated to circulate that season,” he said.

He reminded patients that the flu vaccine is not complete protection against getting sick, but said it provides protection against severe complications including hospitalization and death.

“While we await data on the impact of the 2023-2024 seasonal covid-19 vaccine on hospitalizations and deaths, all prior doses have demonstrated this benefit particularly in people vulnerable to complications,” said Snyder.

The RSV vaccine is only available to people over 60 years of age and pregnant mothers. Snyder encourages those populations to get vaccinated.

He said that RSV has the greatest impact on newborns and older people, and that’s why the vaccination strategy has been focused just on these two groups.