The World Health Organization (WHO) is calling for a moratorium on all booster shots worldwide to prevent the supply for COVID-19 vaccine doses from dwindling amid the huge demand in several hard-hit nations.

Tedros Adhanom Ghebreyesus, the Director-General of the WHO, asked countries to hold off on administering booster shots to residents as the demand for dose supply in other countries is rising. Officials from the agency said the science behind a booster shot for the coronavirus has not yet been proven.

Moratorium on Booster Shots

While many people believe a booster shot could increase an individual's protection against the COVID-19, the UN Health Agency has called out to more developed countries to support struggling nations with keeping up with the supply of vaccine doses.

Ghebreyesus noted that the WHO set a target earlier this year to vaccinate at least 10% of the population of each country against COVID-19. On Wednesday, the WHO director-general said the agency was calling for a moratorium on booster shots until at least the end of September to allow at least 10% of every nation's population to be inoculated, Fox News reported.

The health agency has been trying to give adults, healthcare workers, and other target populations better access to the vaccines to increase the chances of fighting against the pandemic before focusing on booster shots.

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While the WHO has no authority to mandate how countries act amid many nations previously ignoring its appeals on other issues such as vaccine donations, it continues to urge leaders to think more carefully about their actions.

Dr. Bruce Aylward, a special adviser to Ghebreyesus, said the request to stop booster shots was an appeal to country leaders worldwide to suspend the distribution of the unproven treatment. The medical expert said they would have to wait for the rest of the world to catch up first in vaccinations before allowing booster shots, the Associated Press reported.

Lingering Vaccination Hesitancy

The statements came as United States President Joe Biden on Tuesday implored unvaccinated residents to get inoculated. The Democrat's calls came amid his request on resistant Republican governors to "get out of the way" of vaccine rules if they did not plan to enforce them.

The U.S. president said people were trying to do the right thing and some politicians were hampering those efforts. In the last week, Biden has become increasingly more willing to act on what he was previously hesitant to do.

Biden has worked to keep politics out of his efforts to vaccinate Americans during the early days of his presidency. But the increasing opposition to vaccination efforts as some Republicans' behaviors has made him lose his patience.

Another surge of coronavirus cases threatens the health and safety of Americans once again amid the rising number of cases brought by the Delta variant. Later, a reporter asked Biden about governors from Florida and Texas specifically. The Democrat claimed the officials' decisions were unsound, CNN reported.

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