Study shows vaccine offers little lasting protection against Covid

The Covid vaccines, while protecting against hospitalization and death, offer little protection against long time covidAccording to research published Wednesday in the journal Natural Medicine.

The findings disappointed, if not surprising, for researchers, who had hoped that vaccinations could dramatically reduce vaccinations. long covid risk.

Compared with an unvaccinated individual, the risk of sustained Covid disease in a fully vaccinated individual is reduced by only about 15%, the study found.

Ziyad Al-Aly, a clinical epidemiologist at Washington University in St. Louis and lead author of the study, said: “Vaccines are miraculous at doing what they are designed to do” – i.e. preventing hospitalization and death. But they “provide very modest protection against long Covid,” he said.

Covid vaccines were developed very early in the pandemic, long before doctors, scientists and patients knew of Covid’s existence. Al-Aly, who is also a research lead for the VA St. Louis, said they were never designed to protect against it. “We need to rethink them now because we know that viruses can also have long-term consequences.”

Dr. Greg Vanichkachorn, director of the Mayo Clinic Covid Rehabilitation Program in Rochester, Minnesota, who was not involved in the new study, said the results were not “too surprising.”

“We know that the majority of people with long-standing Covid disease don’t have severe infections,” he said.

The study looked at national health care data from the U.S. Department of Veterans Affairs and included the medical records of nearly 34,000 vaccinated people with the breakthrough Covid-19 infection and more than 113,000 unvaccinated people when infected. Covid from January 2021 to October 2021. People are considered fully immunized if they have received two doses of Pfizer-BioNTech or Moderna vaccine or one dose of Johnson & Johnson vaccine.

The researchers followed up six months after infection to see if The patient has persistent symptoms. While protection against Covid lasts overall is relatively small, vaccines are more effective at preventing some of the most life-threatening long-term Covid symptoms: Vaccination reduces risk lung disorder nearly 50% and coagulopathy 56%, compared with unvaccinated individuals.

Al-Aly notes that a breakthrough case does not mean that a person will develop Covid for long – only about 10% of breakthrough cases will lead to the condition – but with so many people infected, this still transfer to a large number of people.

The data doesn’t show whether a person gets a boost, but Al-Aly said he doesn’t expect the boost to make a big difference in terms of vaccine protection against Covid lasting, nor like variations like omicron.

Vanichkachorn agrees. “Unfortunately, I don’t think boosting will do much to prevent Covid lasting with a vaccine,” he said. “We have as many patients with the breakthrough infection as immunized as possible. We also don’t see much difference between the variants that have persistent Covid symptoms.”

This is not to say vaccines are not an important tool in the fight against the pandemic, experts say.

AcceleratorIn particular, offers the best protection against severe acute Covid and reduces the risk of complications, said Dr. Jason Maley, director of the Critical Illness and COVID-19 Survivors Program at Beth Israel Medical Center Deaconess in Boston said.

But for the long-term Covid, they are not necessarily the solution. “I don’t believe vaccination is the key to eliminating perennial Covid,” Al-Aly said. “We really need to think about additional layers to protect us from the long-term consequences of this virus.”

Covid cases are once again on the rise in the US, now driven by an omicron subvariable known as BA.2.12.1, according to the report. Centers for Disease Control and Prevention. Even so, public health measures such as wearing masks and keeping social distance have largely disappeared.

Al-Aly says he doesn’t blame people for that.

“It’s not practical to tell everyone to wear masks for the next 10 years,” he said. But it highlights the need to improve vaccines and treatments in a way that can provide lasting protection from Covid.

“Now that we have lifted all other public health measures, a vaccine is really the only layer of protection we have,” Al-Aly said. “That raises the more pressing question of what other prevention or treatment measures might be available. Can we tailor those early vaccines to tackle the lingering Covid problem?” Or do we also need nasal vaccines or other therapies?”

For example, vaccines injected into the nose are better able to prevent transmission than current vaccines, but this is an area that needs to be studied, he said.

Maley, who was also not involved in the study, said that engagement studies showed that one of the main risk factors for prolonged Covid is the level of virus in the body during the acute infection phase. This suggests that early treatment with therapies that include antiviral drugs can help prevent long-term Covid by keeping those virus levels low.

“Currently, antiretroviral drugs have been approved for emergency use by patients at high risk for severe Covid-19 illness, often the elderly or those with pre-existing medical conditions,” said Maley. compromised immune system. He is also interested in studying whether antiviral treatments can benefit long-term Covid patients.

Both Al-Aly and Vanichkachorn agree that more long-term Covid research is needed. “We need to continue long-term Covid-specific studies so we can develop specific therapies,” Vanichkachorn said.

But right now, he said, “the best way to stay Covid-free for long is to not take Covid.”