Stress and depression may weaken your immune response to COVID vaccines, studies show

Both available coronavirus vaccines have been shown to be highly effective at preventing infection during clinical trials, but a new review of nearly 50 studies on other vaccines suggests people’s mood and overall well-being play a role in how well their body’s respond to the COVID-19 shot.

Specifically, feelings of stress, depression and anxiety, as well as poor health, can negatively affect a person’s immune response to a vaccine.

These consequences can include a delay in the production of antibodies following vaccination, a reduction in how long immunity lasts and a more intense experience with side effects such as fatigue and muscle soreness.

The research team reviewed 49 studies on a variety of vaccines such as those for influenza, hepatitis B, typhoid and pneumonia dating back 30 years. They found consistent findings across different shots, suggesting to the researchers that they apply to the COVID-19 vaccines, as well.

Negative feelings and behaviors can hamper immune systems from working properly because they can produce loads of the hormone cortisol, which can “open the door” for inflammation, said Dr. Leonard Calabrese, a clinical immunologist with the Cleveland Clinic, who was not involved in the new study.

Stress can also lower the body’s lymphocytes — white blood cells that fight infections — increasing someone’s chances of getting sick.

A pandemic of hardships

Experts worry that ongoing job loss, isolation, economic stressors and other hardships brought on by the pandemic are fueling a mental health crisis that has the potential to weaken vaccine efficacy, “particularly among the elderly,” according to the non-peer reviewed study to be published in the journal Perspectives on Psychological Science.

“When we think of vaccine efficacy, we often think of the vaccine itself. My motivation was to draw attention to the fact that we bring important factors to the table as well — and those factors are modifiable,” study lead author Annelise Madison, a clinical psychology graduate student at The Ohio State University, said in a news release.

Managing stress with exercise, meditation, proper sleep and a healthy diet can help “ensure that the best and strongest immune response happens as quickly as possible” following vaccination.

The researchers also say now may be a good time for people with depression to seek professional help, if needed, as COVID-19 vaccines become more available across the country.

“I know it can be difficult day in and day out during the pandemic to keep prioritizing things we know we should do,” Madison said. “But we could use this time as a wake-up call. These are important health behaviors to keep engaging in, especially as we’re preparing to get vaccinated — which is a really good thing.”

A vaccine’s ‘Achilles heel’

Included in the review was a study of medical students’ response to the hepatitis B vaccine, according to the release. All participants developed antibodies, but those who were more stressed or anxious took longer to produce them.

A separate paper showed that antibodies to the pneumonia vaccine in older adults who cared for spouses with dementia and deemed “chronically stressed” disappeared more quickly than those in non-stressed adults.

Another study published in 2017 found that only positive mood over negativity, physical activity, diet and sleep predicted how well older adults responded to their influenza vaccine, based on higher levels of antibody production.

“Vaccinations are an incredibly effective way of reducing the likelihood of catching infectious diseases. But their Achilles heel is that their ability to protect against disease is affected by how well an individual’s immune system works,” study author Kavita Vedhara, a health psychology professor at the University of Nottingham in England, said in a news release.

“We have known for many years that a number of psychological and behavioral factors such as stress, physical activity and diet influence how well the immune system works and these factors have also been shown to influence how well vaccines protect against disease,” Vedhara added.

Research has also shown that getting good sleep the night before a vaccination can improve a person’s immune response to it.

University of California, Berkeley sleep specialist Matthew Walker told CNN in October that poor sleep in the week before getting a flu shot “can lead to the production of less than 50% of the normal antibody response — a reaction that would render the flu shot largely ineffective.”