A fully vaccinated Houston marriage led to 6 cases of the Delta variant. Have some vaccines saved lives? – .
July 10, 2021https://www.fr24news.com/a/2021/07/...-variant-have-some-vaccines-saved-lives.html#
A couple hosting an outdoor wedding outside of Houston in April demanded a full COVID-19 vaccination from all of their guests. It was an outdoor event, with 92 people in attendance.
Their happy day turned into a nightmare, however, after the death of one participant, two more were hospitalized with serious illness and three more tested positive for the coronavirus. In a pre-printed study on the breakthrough infections of the COVID-19 Delta variant among guests who received the vaccine,
researchers at Baylor College of Medicine say the new dominant strain of the virus may pose the greatest risk of infection. high of all variants spreading in the world.
The deceased was vaccinated with Covaxin, a vaccine not authorized for emergency use in the United States. One of the hospital patients received Covaxin, while another received Pfizer. The two recipients of Covaxin had come from India for the wedding.
The three people who caught the virus but exhibited mild symptoms were vaccinated with Pfizer or Moderna products.
“All current data shows a robust ability to block severe disease from the Delta variant,” said Tim Farinholt, one of the study’s authors. “This is not to scare, it is to remain cautious that the pandemic is not over and to remain vigilant. It’s up to people to know that just because you’re vaccinated doesn’t mean you can come back to 2019 alive. “
A pre-printed study has not been evaluated by independent scientists and should not be used to guide clinical practice, the researchers said. However, this is a preliminary finding to relay interesting developments and help other scientists determine what to study. The peer review can take two to four weeks.
Unvaccinated people account for the majority of hospitalizations and deaths related to COVID-19 reported in the United States in recent weeks, according to infectious disease specialists. Of the tiny fraction – less than 3% in the Baylor study – who are vaccinated and get serious infections, most have other comorbidities or are immunocompromised. One of the patients who contracted a serious illness had diabetes and received monoclonal antibody infusion therapy. The deceased patient did not have a chronic illness, but was over 65, an age group at increased risk for serious infections.
All six infected people tested positive for the Delta variant. The other three wedding guests who caught COVID-19 and were vaccinated with Pfizer and Moderna had mild symptoms such as fever, cough and fatigue. The results align with the efficacy rates promised by pharmaceutical giants in their clinical safety trials, said Dr Pei-yong Shi, professor of biochemistry and molecular biology in the medical branch of the University of Texas at Galveston , which independently reviewed pre-print on demand. from the Houston Chronicle.
“The vaccine didn’t absolutely prevent you from getting infected,” Shi said. “But one of the main benefits is that it keeps you from getting really sick. “
Covaxin, a vaccine developed from inactive coronaviruses, has an efficacy rate of 81%, according to BBC News. However, the drugmaker came under fire in January after being cleared for emergency use during its clinical trial phase.
In comparison, Pfizer’s vaccine is 95% effective and Moderna’s vaccine is 94% effective against the original virus strain. Various studies have been published on the effectiveness of the vaccines and the Delta variant, ranging from 64 percent effectiveness to 88 percent effectiveness.
The preprinted journal article linked Delta, which features mutations in part of the spike protein that could help it strengthen its binding to receptors in a cell, as the cause of breakthrough infections. Delta, which some epidemiologists say is 60% more transmissible than the original strain of SARS-CoV-2, already accounts for more than half of new infections in the United States
Houston Methodist researchers earlier this week published results that said the Delta variant could account for 92% of all new infections in the coming weeks if it continues at its current rate of spread.
“It’s hard to say if the breakthrough they’re seeing is something that is a hallmark of Delta or if it’s something that happens occasionally. We don’t have data to say a coincidence from a rare event at this point, ”said Ben Neuman, virologist at Texas A&M.
While the wedding is only a case study, it’s also remarkable that the event took place in April – long before Delta became the dominant variant in the US, UK, Israel, and Australia. India, said Joseph Petrosino, one of the co-authors and director of the study. of Molecular Virology and Microbiology at Baylor College of Medicine. The first cases of the Delta variant were reported in the US and UK from mid-April to late.
Contact tracing showed that none of the infected patients had recently interacted with someone who had tested positive for a different variant of COVID-19.
“The epidemiology combined with the sequencing data suggests that the variant was shared within the group,” said Petrosino.
Another conclusion of the study? The two Indian travelers likely brought the Delta variant to the wedding.
“It is not known if people can transmit with both doses of the vaccine,” Petrosino said. “There seems to be a lot of evidence to suggest that if your vaccine did not elicit a significant immune response, which is possible with a single dose and the Delta variant, you can still pass it on. “
Feeling unwell after a second dose of the vaccine is not the only indicator of the strength of a person’s immune system. But studies show that mRNA vaccines such as Pfizer and Moderna provide robust protection in 90 percent of recipients.
Scientists caution against using the study to justify skipping vaccinations. If someone is not fully vaccinated and carries the infection to an under-vaccinated community, it could spread the virus even further and cause new variants to mutate.
Vaccines aren’t perfectly effective, but they offer more protection than what the human body starts with against coronaviruses, said Katelyn Jetelina, an epidemiologist at the University of Texas Health Sciences Center at Houston.
“We have to be careful about how we frame the case study and what we get out of it,” Jetelina said.
