African doctors and health officials on Tuesday denounced the U.S. Centers for Disease Control (CDC) for recommending Pfizer and Moderna vaccines above Johnson & Johnson, after it reported the J&J vaccine carries a small risk of causing blood clots.

J&J is the most widely used vaccine in Africa, which has been struggling to inoculate its population against the Chinese coronavirus. African doctors said they consider the J&J vaccine perfectly safe and felt the CDC recommendation would cause “irreparable” damage to Africa’s vaccination efforts by needlessly frightening an already recalcitrant public.

Several African health authorities criticized CDC in remarks to Voice of America News (VOA):

“I’ve been inundated with calls from people saying, ‘You’re poisoning us’ and ‘We don’t want to take this’ and ‘We’re getting second-hand vaccines; we shouldn’t be getting the J&J, we should only be getting the Pfizer,'” said Barry Jacobson, president of the Southern African Society of Thrombosis. “The CDC, by putting out this statement, has made people scared about taking the J&J booster, and they shouldn’t be.”

South Africa’s top epidemiologist, Salim Abdool Karim, maintains J&J’s vaccine is safe.

“If you had to just look at, for example, thrombosis from cases of COVID-19, it’s far higher than from what we see from the vaccine,” said Karim, an epidemiologist at South Africa’s University of KwaZulu-Natal, who previously advised the South African government on COVID-19 [Chinese coronavirus]. “So there’s no question that this vaccine has a net benefit, even in the face of these side effects.”

Jacobson added that the risk of thrombosis is present with all of the vaccines, and “massive” from Chinese coronavirus itself, so he felt it was unreasonable to single out J&J as the CDC did.

The CDC recommendation that angered African doctors said thrombosis is “rare” with J&J, citing 57 confirmed reports in the United States after 16.9 million doses of J&J were administered.

The highest-risk group appears to be women in their 30s and 40s, and the symptoms of blood clotting usually appear within nine days of receiving the injection.

The advisory committee that studied the vaccines also concluded J&J’s product is somewhat less effective at repelling Chinese coronavirus than the Pfizer and Moderna vaccines, which were created with mRNA technology, but J&J requires only a single dose and its vaccines can be stored at higher temperatures, which are advantages for patients in inaccessible regions – a major reason why Africa has come to rely on the J&J product.

CDC stated that “receiving any vaccine is better than being unvaccinated,” given “the current state of the pandemic both here and around the world,” but expressed a “clinical preference” for Pfizer or Moderna over J&J.

South Africa last week pledged to donate over two million doses of J&J vaccine to other African countries over the coming year.

“This donation embodies South Africa’s solidarity with our brothers and sisters on the continent with whom we are united in fighting an unprecedented threat to public health and economic prosperity,” said South African President Cyril Ramaphosa, who tested positive for Chinese coronavirus himself and just completed a week of self-isolation.

“The only way in which we can prevent COVID-19 transmission and protect economies and societies on our continent is to successfully immunize a critical mass of the African population with safe and effective vaccines,” Ramaphosa said.

According to the World Health Organization, Africa is the least vaccinated populated continent in the world. Only 20 of Africa’s 54 countries have fully vaccinated ten percent or more of their populations. Ten countries have fully vaccinated less than two percent of their populations. 

About 38 percent of South Africans are fully vaccinated, but on Friday Health Minister Joe Phaahla said he was worried about “the drastic decline in the uptake of vaccinations, especially in the last seven to 10 days.”