Though the daily march of new cases of COVID-19 has continued in a grim, upward trajectory, the numbers of hospitalizations and deaths have remained relatively lower than expected.

UPMC doctors attribute this to a new COVID-19 strain that has emerged, that may be more infectious, but less virulent than the original strain that started the global crisis.

“You may have heard in the news that there is a dominant global strain, one that seems to transmit easier but is less deadly,” said UPMC Medical Director of Infection Prevention and Hospital Epidemiology Graham Snyder, at a press conference on Thursday.

“That’s the strain that we’re detecting, and our data supports those characteristics. Additionally, we’re finding a lower viral load, meaning less virus within the person in the samples that we collect from our patients for testing. We don’t know for sure why this is, but suspect that seasonality, particularly humidity, impacts virus transmission.”

The rise in cases does not seem to be corresponding with a jump in patients requiring serious intervention.

“What appears to be happening with this strain of virus is that it appears to be more readily transmitted, but less likely to cause serious outcomes of infection,” said Snyder. “In other words, we’re less likely to see somebody require a ventilator in the hospital, for example.”

“We’re also not seeing the same mortality that we were seeing in the spring at the emergence of the epidemic.” Only 2% of recent infections are causing illness severe enough to result in hospitalizations, with one-tenth of those hospitalizations resulting in death.

Another likely reason is that younger people in Allegheny County are becoming infected at a much higher rate than earlier on in the pandemic.

“Our testing data, and that of our partners at the county and state health departments, indicates that these cases are largely linked to younger people who contracted the virus while traveling or while socializing without masks or proper social distancing,” said Snyder. “The median age is under 30. We’ve learned that this virus is not as severe in this age group.”

“Systemwide, we have 118 people hospitalized. The average age of these hospitalizations is over 60. The rate of hospitalization has not kept pace with the rate of growth of positive test cases that we’ve seen. We’d expect to see more patients with severe lung disease, needing ventilation.”

Despite the rise in overall cases, efforts to protect the vulnerable seem to be paying off.

“Right now, the data indicates that we as a community are doing a good job protecting those we have learned are most vulnerable to bad outcomes from COVID-19: the frail, elderly and those who are immunocompromised,” said Snyder. “And the infection prevention measures we’re taking in our hospitals are working.”

The virus can be transmitted by asymptomatic carriers, as well as before symptoms are shown. It’s also not going away.

“The virus will be with us for the foreseeable future,” explained UPMC Senior Medical Director and Chair of Emergency Medicine Donald Yealy.

It’s not a time to let one’s guard down.

“Wear a mask in public always,” said Yealy. “Wear it properly, cover your mouth and your nose. Stay home if you’re sick and stay home if you can. Large congregations put people at risk. Wash your hands. Stay extra vigilant, to protect the elderly and those who are vulnerable. You can’t always tell from looking who’s vulnerable, so follow these simple steps, always.”

Tracing the contacts of those who have been exposed to the virus is essential to limiting the spread.

“If you’re contacted about a tracing from either a symptomatic or asymptomatic patient, let me ask that you really participate,” said Yealy. “We’ve heard reports of people who just won’t respond to these requests. This goes beyond Big Brother watching you, or a personal rights kind of issue. This is how we protect all of us — including some people who you’ve come in contact with, whom you don’t know if they’re vulnerable. I really would ask that you help us fight this disease together.”