By Julie Steenhuysen

CHICAGO (Reuters). Currently, the United States has announced that those over 50 years old can now get a second COVID-19 boost shot to increase their immunity. The decision for those in this group is more complicated.

These are the things that health professionals recommend people weigh.

WHAT IS THE RECOMMENDATION

According to the U.S. Food and Drug Administration and Centers for Disease Control and Prevention, anyone 50 years old or older could get an additional COVID-19 booster for an mRNA-vaccination from Moderna (NASDAQ:) Pfizer/BioNTech minimum four months after their last shot.

The same goes for people who are severely immunocompromised aged 12 and up as well as those who have received two doses of Johnson & Johnson (NYSE:)’s shot.

Director of FDA’s Center for Biologics Evaluation and Research Dr. Peter Marks stated that the goal is to allow older people to supplement their waning protection against severe diseases as long as there are still circulating the virus.

Omicron BA.2 is a highly transmissible subvariant that has fuelled cases in other countries. It now dominates the United States and accounts for most coronavirus-related infections.

WHAT IS THE EVIDENCE?

Last week, data presented by FDA advisors showed that vaccines have lost much of their effectiveness against Omicron-related infections but are still effective in preventing serious disease in healthy people. U.S. officials approved a second booster because of concerns about how the Omicron variant could evade vaccines and data that showed shots becoming less effective over time.

A study by Israel of more than 1.2million adults, published last week in The New England Journal of Medicine, supports the idea of an additional booster. The study showed that the fourth dose of BioNTech/Pfizer vaccine had a lower rate of severe COVID-19 in older adults, but it did not provide additional protection.

WATCHING FOR RISK

Experts advise that the decision whether or not to receive a fourth dose must be taken into consideration.

According to Dr. William Schaffner of Vanderbilt University Medical Center, this is the right answer for those 65 years and over, as well as people with severe medical conditions. A second booster should be given to them.

Experts aren’t sure if there is enough data to support the recommendation that healthy older adults get another boost.

“There’s no clear evidence that vaccine protection against severe illness is waning in healthy adults with functioning immune systems,” said Dr. Michael Daignault, and emergency physician and chief medical advisor to Reliant Health Services, an Atlanta-based testing company.

Daignault stated that confounding variables such as preexisting medical conditions or behavioral patterns may have caused the Israeli study to be flawed.

He stated, “I am not convinced most people require a fourth dose or second booster at this point.”

Gregory Poland (ex-FDA vaccine advisory panel member, Mayo Clinic’s Vaccine Research Group Head) said that the decision was difficult for many.

He said, “I receive many, many calls by my physician colleagues in the clinic and across the United States asking what I should do.”

People who have received a third dose of vaccine are at a lower risk for severe illness, according to Dr. Jesse Goodman from Georgetown University. He is also an expert in infectious diseases and former chief scientist at FDA.

Goodman indicated that while a fourth dose could reduce its effectiveness, we do not know how long it will last. He said that this was why it is so difficult to make a decision.

Goodman is 70 and Poland is 66. They both indicated that they have decided to hold off on taking a fourth dosage based on current health.

Poland suggests that people consider timing their shots for trips, high-risk events, and new cases to maximize protection.