MANILA - The World Health Organization (WHO) on Tuesday urged countries to "hold back" on providing booster shots as experts have yet to see "any evidence" that an additional dose of COVID-19 vaccine could prevent breakthrough infections.

Experts are "not sure if boosters with the existing vaccines are going to protect" people against COVID-19 as the more virulent Delta variant has reduced the efficacy of the jabs, WHO country representative Dr. Rabindra Abeyasinghe said.

"We have not seen any evidence," he said in an online press conference.

"If we agree to that without evidence, we are actually putting at risk people who have not had even a single dose. That is ethically incorrect," he said.

"That is why we are calling for countries to hold back until there is evidence that a booster dose will add benefit," he said.

• DOH says COVID-19 booster shots not yet needed in PH

If countries want to prevent breakthrough infections, more senior citizens and persons with comorbidities should be fully vaccinated which waiting for a second generation vaccine, Abeyasinghe said.

"We may need a second generation vaccine," he said.

"Once we have that, we can decide what is the most appropriate time for a booster dose, what should be that booster dose... We don't have any of that information now," he said.

• Health chief laments rich countries talking of COVID booster shots while millions unvaccinated

In June, the WHO said that people most vulnerable to COVID-19, such as the elderly, will need to get an annual vaccine booster to be protected against variants.

The forecast is subject to changes and is also paired with two other less likely scenarios, according to an internal document seen by Reuters.

• WHO estimates COVID-19 boosters needed yearly for most vulnerable

The Department of Health (DOH) earlier said that its proposed 2022 funding for COVID-19 booster shots has been cut to P45 billion.

The Department of Budget and Management had put the budget for vaccine booster doses under unprogrammed funds at P45 billion since the Philippines has yet to decide if it would administer boosters next year.

• Proposed 2022 funding for COVID-19 booster shots cut to P45 billion: DOH

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