Experts: Personal behavior is key to decline in virus cases and deaths

New cases have dropped substantially since beginning of 2021

Daily COVID-19 cases statewide and nationally continue to decline as a result of measures taken to mitigate the virus’s spread, and the trend may continue as long as people hunker down and new variant cases don’t increase more rapidly than vaccinations, experts said Tuesday.

Throughout January, Pennsylvania saw new cases of COVID-19 drop substantially. During the week of Jan. 1, the state saw approximately 42,300 cases of the virus, but that number dropped to about 26,000 new cases during the month’s final week.

The decline likely has been caused by measures taken by citizens to slow the spread of the virus during the holiday season, public health researchers interviewed by the Pittsburgh Post-Gazette said, including avoiding gatherings and travel during the Christmas and New Year’s holidays.

“What we have seen around the holidays — Thanksgiving and Christmas especially because they tend to be family holidays — Americans did an amazing job, I mean a really amazing job, by controlling the spread,” said Ali Mokdad, a professor with the Institute for Health Metrics and Evaluation at the University of Washington.

The professor attributed the good performance to the likelihood that rapidly increasing cases and deaths, alongside strong warnings about holiday gatherings from public health officials, made Americans more vigilant of their behavior and hesitant to get together.

“I hope this will continue as we see a decline,” he said.

Now, researchers said they are wary of the spread of new variants, like the ones first discovered in the

U.K. and South Africa, which can be more contagious and even more deadly.

The one variable that could stop the variants from becoming the dominant virus strain in the U.S. would be getting more vaccines into people’s arms, said Dr. Amesh Adalja, a senior scholar at Johns Hopkins Center for Health Security.

“I would say several million [vaccinations] a day are what I’d want to see,” Dr. Adalja said. “I don’t think there should be any speed limit, so the more the better.”

The New York Times, which tracks vaccinations using data from the Centers for Disease Control and Prevention, estimates providers are administering an average of about 1.4 million doses of the vaccine per day.

In Pennsylvania, more than 916,000 people have received at least

one dose of the two-shot vaccine, according to the CDC.

In addition to increased vaccinations, Mr. Mokdad said two other conditions are essential to keeping the virus in check: There must be no new variant that will seriously affect the efficacy of the vaccine, and people must continue to behave carefully.

“We are concerned when the American public sees all these great indicators — vaccines are going up, cases are coming down — they will relax, and they will not be as vigilant,” he said. “And with the new variants, we’re going to see a surge in cases.”

Some vaccines appear to be less effective against the South African variant, but Mr. Mokdad said the key is to remember all of the vaccines available in the U.S. will generally be effective at preventing severe illness and death.

He said he plans on taking whatever vaccine is available to him when his turn comes, and he’s been giving the same advice to his family. Some manufacturers are already looking into how to increase the vaccines’ efficacy against the virus.

Right now, it’s a race between the vaccine and the virus, said Jeffrey Shaman, a professor at Columbia University’s Mailman School of Public Health.

The two variables in our control are non-pharmaceutical interventions, such as masks and social distancing, and accelerating vaccinations, he said.

A big risk, a December article published by Mr. Shaman and his colleagues warns, is that easing distancing measures will lead to another surge before vaccines get a foothold in the wider population.

“Even though we’re on a downward trend, if we start opening up restaurants and whatnot, we’re not going to be on that same downward trend,” he said. “It might still be downward, but it might be less so. And you’re going to be accumulating more infections, cases, hospitalizations and deaths than you would otherwise.

“You’d like to actually suppress the virus transmission as much as possible and get the vaccine out as quickly as possible and into people’s arms.”

Meanwhile, Pennsylvania on Tuesday recorded 4,410 new cases of COVID-19 and 125 deaths from the virus.

The new numbers bring the state’s total to 850,488 cases and 21,812 deaths since mid-March, according to the Pennsylvania Department of Health.

Allegheny County added 300 COVID-19 cases to its count and confirmed eight more deaths from the virus, the county Health Department reported.

The new deaths ranged from Dec. 29 to Jan. 31 and included one person in their 20s, a person in their 50s, two people in their 60s, two in their 80s and two more in their 90s. Three of those people were associated with long-term care facilities.

The Allegheny County Health Department declined to release more information about the person in their 20s, one of only a few in that age range to die from the virus locally. Although they are generally less vulnerable to getting severe symptoms of the disease, people aged 20 to 29 account for 20% of local cases, the highest percentage of COVID-19 cases in the county among any age grouping, according to the county Health Department.

Newly infected people range in age from 3 to 97 years, making a median age of 41. One test dated back to Dec. 13, while 26 others were from January. The majority of the tests were conducted in the past week.

The county Health Department said it investigates delayed results and refers any labs with delays to the state.

Of the new positives, 153 are confirmed cases and 147 are probable.

To date, ACHD has reported 69,837 cases of COVID-19 in county residents, causing 4,412 hospitalizations and 1,462 deaths.