Time zone is important when inoculating COVID vaccine – Harvard Gazette

Our internal 24-hour circadian clock regulates many aspects of physiology, including infectious diseases and responses to vaccination.New research published in Journal of Biological Rhythms It shows that people have higher antibody levels when they receive the SARS-CoV-2 vaccine in the afternoon and in the morning.

“Our observational studies provide evidence of the notion that time affects the immune response to SARS-CoV-2 vaccination, which may be related to optimizing vaccine efficacy. “It’s a finding,” said Elizabeth Clarman, co-chief author and researcher in the Department of Neurophysiology. A sleep unit at Massachusetts General Hospital, a professor of neurology at Harvard Medical School.

The symptoms of some illnesses and the effects of many drugs vary from time to time. People with lung disease, for example, often have more severe symptoms and altered respiratory function at certain times of the day. A study of older men vaccinated against influenza showed that they had higher antibody titers when they were vaccinated in the morning compared to the afternoon.

“Studies have shown that administration of several chemotherapeutic agents at specific times effectively targets cancer cells but limits toxicity to other cells,” Klerman said. increase. The authors propose a role in circadian signaling in the regulation of SARS-CoV-2 immune response and COVID-19 severity.

An observational study evaluated antibody levels after SARS-CoV-2 vaccination in 2,190 healthcare workers in the United Kingdom. Blood samples were collected from asymptomatic hospital personnel at the time of vaccination as part of the UK infection prevention program. Researchers have created a model to investigate the effects on antibody levels based on the time of vaccination, type of vaccine (Pfizer mRNA vaccine or AstraZeneca adenovirus vaccine), age, gender, and number of days after vaccination. Did.

Researchers found that antibody responses were generally higher in all vaccinated people later in the day. Antibody responses were also higher in people, women, and young people vaccinated with the Pfizer mRNA vaccine, in addition to the effects of vaccination time.

The SARS-CoV-2 study contrasts with previous studies of older men who reported high anti-influenza titers in the morning. Potential Reasons for Different Findings: “SARS-CoV-2 and influenza vaccines have different mechanisms of action, and the antibody response depends on whether the immune system recognizes pathogens from early infections such as influenza. It can be very different, or whether it faces a new virus, “says Klerman.

The limitation of the study is the lack of data on participants’ medical history and medication history, sleep and shift patterns, which can also affect vaccine response.

“Before recommending it to anyone who wants to further enhance the vaccine, such as the elderly, it is necessary to reproduce the findings and gain a better understanding of the underlying physiology of SARS-CoV-2 and the body’s response to vaccination. People with immunodeficiency should be scheduled to be vaccinated in the afternoon, “says Krelman. “This study is the first step in demonstrating the importance of time response to the SARS-CoV-2 vaccine.”

Klerman emphasizes that vaccination is the most important step in preventing COVID-19 infection, regardless of time of day.

These data also underscore the importance of recording the time of vaccination or intervention in clinical and research studies. “If preliminary data show differences in time-based drug or vaccine efficacy and side effects, pharmaceutical companies are advised to administer the drug at the optimal time, which is statistically significant. It reduces the number of participants needed to get things. The difference between medicine and placebo, “says Krelman.

Klerman and her colleagues are currently analyzing data on vaccine side effects from people vaccinated at a common Brigam facility in Massachusetts. “We find that the higher the antibody levels when people are vaccinated in the afternoon, the greater the side effects,” says Klerman. She also wants to have the opportunity to re-analyze data from randomized controlled trials of the SARS-CoV-2 vaccine to determine if the time when participants received the vaccine affected efficacy. I am.

Other major authors include Wei Wang, an assistant professor of medicine at HMS and an associate mathematician at Brigham and Women’s Hospital. Peter Balfe, Research Scientist, Nafield School of Medicine, University of Oxford. Jane Mackie, a professor of molecular biology at Oxford University.