WASHINGTON -- As the United States is hoarding COVID-19 vaccines, many developing countries are still struggling to get access to doses, with exacerbating inequality of vaccine access, according to US media.

"In India, just 1.4 percent of the population has been fully vaccinated, and overwhelmed hospitals have been running short of oxygen. Meanwhile, in the United States -- where one in four Americans are fully vaccinated and more than 40 percent have gotten at least the first dose," said a report published by the Washington Post on Sunday.

Countries in dire need of vaccines are calling for policy changes in Washington, and African nations such as Namibia and Kenya are denouncing a "vaccine apartheid," the report said.

Maria Van Kerkhove, an epidemiologist with the World Health Organization (WHO), described global vaccine inequities as "outrageous ethically, morally, scientifically."

"We have all the kindling to start fires everywhere," she said in an interview. "We're siting on a powder keg."

Countries with high inoculation rates are seeing declines in COVID-19 infections, while globally, the number of new cases per week has nearly doubled since February, WHO data showed.