The Food and Drug Administration could unveil a nationwide strategy on COVID-19 booster vaccines as early as next month amid the ongoing surge in new infections linked to the highly transmissible delta variant of the virus, according to reports.

The Wall Street Journal, citing people familiar with the agency’s discussions, first reported that the administration of President Joe Biden is working quickly to develop policies around booster shots amid concern about the ongoing length of the pandemic and if those who are vaccinated will remain protected, particularly Americans that are more susceptible to severe infection.

The push comes amid a dramatic surge in cases, with new infections rising in every state in the country and some hospitals reporting they are running out of beds.

About half of the country has been fully vaccinated against COVID-19. Inoculations remain the most effective way to prevent severe cases of the coronavirus or death associated with the disease, including against the delta strain. A small group of vaccinated people have reported breakthrough infections of COVID-19, but very few require hospitalization or die. Almost all of the nation’s deaths over the past months have been among unvaccinated people.

Both Pfizer and Moderna have reported their inoculations providing lasting protection against severe cases of the coronavirus, but studies have shown vaccines’ effectiveness at preventing symptomatic infection can diminish over time. The companies have said in recent months they expect booster shots will be needed to improve immunity for the foreseeable future as the pandemic continues, a reality that could result in billions of dollars in additional vaccine sales.

There is no clear scientific consensus yet on if boosters will be needed, but public health officials have expressed concern about variants like the delta strain and others that could evolve in the future. The Wall Street Journal added that the FDA is investigating if a multi-course vaccine regimen, like the four-shot program for poliovirus, could result in lifelong immunity or a much longer protection period.

Germany and Israel have said in recent days they will provide booster jabs to subsets of the population considered vulnerable to severe infection, namely older residents and those with compromised immune systems.

The World Health Organization expressed alarm, however, with western nations’ focus on booster jabs this week as many middle- and lower-income nations have yet to vaccinate large swaths of their populations. The group said more than 80% of the vaccines delivered so far have gone to high- and upper-middle-income countries, and WHO’s leader said those who already have advanced vaccination campaigns should help deploy vaccines worldwide so lower-income nations can inoculate at least 10% of their populations. 

“I understand the concern of all governments to protect their people from the delta variant,” Dr. Tedros Adhanom Ghebreyesus, WHO’s director-general, said at a news briefing on Wednesday. “But we cannot — and we should not — accept countries that have already used most of the global supply of vaccines using even more of it, while the world’s most vulnerable people remain unprotected.”