Booster shots will likely be necessary as antibodies from both COVID-19 vaccines and infections wane at the same rate, according to a new UCLA study published Wednesday.

The study published in ACS Nano looked at the two-dose Pfizer and Moderna vaccines, finding that after the second jab, antibody levels decreased an average of 90% within 85 days. That’s the same relatively rapid antibody loss that comes after a natural infection, according to the study.

Senior author of the study, Dr. Otto Yang, said that while more research is needed on the response of the immune system’s long-lasting “memory” T cells to the vaccines, the sharp drop in antibodies suggests that booster vaccinations will likely be needed to maintain protection against the potentially deadly virus.

There has been evidence that immunity from the mRNA vaccines doesn’t just depend on antibodies that dwindle over time, with some experts saying booster shots may only be needed every few years, the Associated Press reported.

It’s also still unclear what levels of antibodies would be sufficient.

But a recent Johns Hopkins University study did find that the booster shots may be beneficial for those who have had transplants.

On Wednesday, Centers for Disease Control and Prevention scientists said there isn’t enough data to support recommending COVID-19 booster shots for the general public.

Still, Pfizer and Moderna are both working on getting booster shots ready.

Moderna expects to have the jab ready much faster than the original vaccines, the company’s president, Dr. Stephen Hoge, told the AP.

UCLA’s study also found that having a previous COVID-19 infection could serve as the first “dose” of a two-dose vaccine, with researchers saying that one shot provides the same amount of protection in a previously infected person as two doses would in someone who was never infected.

Yang and his colleagues measured the COVID-19 antibodies after one and two doses of the vaccines in people who previously had COVID-19 and those who hadn’t. They found that the second dose provided no additional antibodies for previously infected people.

“Our data suggest that a person who previously had COVID-19 has a huge response after the first mRNA vaccination and has little or no benefit from the second dose,” Yang said.

The professor said it’s worth changing public health policies to take this into account in order to maximize vaccine usage and avoid unnecessary side effects.