Research News

UB researchers provide update on delta variant, long COVID

illustration of COVID variants.


Published August 17, 2021


Keeping up with all of the science related to COVID-19 is not easy. With so many news sources and so much information circulating on social media, it can be overwhelming and confusing trying to keep all the details straight.

Two of the most recent examples? The delta variant and “long COVID.”

UBNOW recently asked four UB experts to discuss these two emerging topics.

Delta variant

The delta variant is a highly contagious strain of the coronavirus that was first identified in India, and was later responsible for a large outbreak in the United Kingdom. It’s now causing the majority of COVID-19 infections across the country, including Erie County.

headshot of Jennifer Surtees.

Jennifer A. Surtees, associate professor, Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences.

“The delta variant has become the dominant lineage of SARS-CoV-2 in the United States. The delta variant is very contagious — about twice as contagious as the original virus. It makes copies of itself very quickly, leading to a large amount of virus in those who are infected and facilitating its quick spread.

“Once delta is in a community, it has the capacity to spread quickly and easily, infecting people who are not vaccinated. We have seen this happen in places like Florida, Missouri, Arkansas and Louisiana.

“Children under 12, who cannot be vaccinated yet, are most vulnerable and if infected can become quite ill. The best way to protect children and immunocompromised people is for everyone eligible for vaccination to be fully vaccinated. High levels of vaccinated people mean significantly less infection [in the community], thus reducing the spread of the virus.

“Full vaccination — getting both shots of the Pfizer or Moderna vaccines — is really important with delta. We know that the vaccines are highly effective at preventing serious disease with delta when people are fully vaccinated.”

headshot of Tim Murphy.

Timothy F. Murphy, SUNY Distinguished Professor of Medicine, Jacobs School, and director, UB Clinical and Translational Science Institute.

“When it comes to the delta variant, there is good news and bad news. The bad news is that the delta variant is highly contagious and the good news is that all three vaccines available in the U.S. are highly effective in preventing serious delta variant infections.

“Currently in the U.S., over 97% of people in the hospital and 99% of deaths from COVID-19 are in people who are unvaccinated. Rochelle Walensky, director of the CDC, has said it well: We now have a “pandemic of the unvaccinated.”

“Breakthrough cases of COVID-19 in vaccinated people are rare, estimated to occur in less than 1% of people who fully vaccinated. When these cases do occur, they cause asymptomatic or mild disease.”

headshot of Sanjay Sethi.

Sanjay Sethi, CTSI associate director; director, Clinical Research Office; professor and chief, Division of Pulmonary, Critical Care and Sleep Medicine, Jacobs School of Medicine and Biomedical Sciences.

“The delta variant clearly spreads faster than other variants. Though it is less susceptible than other variants to the antibodies we develop after vaccination, almost all people who are fully vaccinated are protected against the variant.”


The Centers for Disease Control and Prevention (CDC) defines long COVID, or post-COVID conditions, as a “wide range of new, returning or ongoing health problems people can experience four or more weeks after first being infected with the virus that causes COVID-19. Even people who did not have COVID-19 symptoms in the days or weeks after they were infected can have post-COVID conditions. These conditions can have different types and combinations of health problems for different lengths of time.”

headshot of Teresa Quattrin.

Teresa Quattrin, UB Distinguished Professor and senior associate dean for research integration, Jacobs School; director, CTSI Special Populations Core.

“The public must be made more aware of COVID-19 frequent long-term conditions, some of which are much worse than losing the sense of smell or taste. We realize that some people have a feeling of unease related to the fact that the vaccine is approved “for emergency use.” However, we need to spread the message that getting immunized is important not only to prevent the disease and its spread, but ultimately also to help reduce the potential for long-term complications [of COVID-19 infections]. This is even more true of the delta variant, where the virus is more contagious, which means that it spreads more rapidly.”

Sanjay Sethi

“We have much to learn about long COVID. [Even so], an evaluation to make sure it is not another disease unrelated to COVID is important. Participation in research in long COVID is also a good idea because only then will we understand it and develop new treatments.”

Timothy Murphy

“Long COVID is causing debilitating symptoms in many people who have recovered from COVID-19 infections. It is important to realize that people who recover from mild COVID-19 infections are experiencing long COVID at a similar rate as those who recovered from severe COVID illness. The vaccines are highly effective at preventing long COVID by preventing acute COVID infections.”

The four researchers say there is still much to learn about the delta variant and long COVID, but all agree on the importance of vaccination.

“The best way to avoid long COVID [and the delta variant] is not to get the virus to start with,” Sethi says. “The only sure way to do that is to get fully vaccinated.”