A battle against the Zika crisis is taking a dramatic turn, with the world’s most powerful health agencies signalling a plan to phase out some of the world, most recently in the US.

Key points:The World Health Organization (WHO) said Monday it would phase out the use of the Zika vaccine by the end of 2019The US National Institutes of Health (NIH) said it would also phase out all Zika vaccines in 2020, but there will be exemptions for babies and pregnant womenThe US government is currently testing about 500,000 people for the virus, and the virus has now spread to more than 200 countries.

The WHO said it will not use the Zika vaccines currently in use by the US and other countries.

It said in a statement on Monday that the WHO would announce its plan for phase out of Zika in 2020.

“The WHO will be issuing an interim statement to highlight the steps we have taken, but the ultimate decision will be made by the World Health Assembly in 2022,” it said.

The US Health and Human Services Department (HHS) is already conducting a vaccine study in which about 4 million doses have been sent to more people, but it has not yet released the results.

“Our vaccine is still on the ground in our laboratory, and we will continue to make progress in our vaccine research and development program to determine whether or not it can provide protection in a timely manner,” HHS said in an email to ABC News.

In a separate statement on its website, the NIH said it had not yet determined the effectiveness of its Zika vaccine and would continue to test people for it.

The Zika virus has caused devastating birth defects in Brazil and has spread around the world.

“We have reached out to other nations to assist them in their testing efforts,” said Dr David Schoenfeld, director of the NIH’s National Institute of Allergy and Infectious Diseases (NIAID), in a news release.

“In the meantime, we will be working with other nations on the WHO roadmap.”

The US is currently conducting about 500 million doses of the vaccine, which contains two proteins: one that binds to a Zika virus protein and the other that can trigger a response.

It has a long way to go before reaching its goal of vaccinating 10 million people a year.

Dr Michael Fadiman, the director of Johns Hopkins University’s Center for Infectious Disease Research and Policy, said the NIH is still testing the vaccine and said it could be months before it reaches the targeted target.

“It is still a very long way from 100 percent coverage of vaccine, but we’re moving very slowly, because we’re still testing it,” Dr Fadim said.

In the US, the number of people who have been tested for the Zika disease has been dropping steadily.

But Dr Fathima Srinivasan, director-general of the WHO’s Division for Global Health, said that even with the vaccines being tested, the virus was still spreading.

“As soon as the vaccine reaches the WHO, it is highly likely that it will be a problem for the rest of the population, because it is a vaccine that doesn’t prevent Zika,” she said.

“So there is a very high risk that this will continue.”

She said the vaccine would also need to be administered to pregnant women, who have a much higher risk of contracting Zika.

The World Anti-Doping Agency (WADA) said on Monday it had tested more than 4 million athletes and found that only around 4% had tested positive for the strain of the virus.

Dr Fadima Slinivasan said that would increase the risk of people not being vaccinated, even if they had tested negative.

“There is a risk of vaccine being misused, and it is the responsibility of athletes to protect themselves,” she told the ABC.

The WADA said the WHO had also failed to provide a comprehensive report on the effectiveness and safety of its vaccine.

Dr Slinasans statement said it was up to the WHO to provide such a report.

“If the WHO cannot provide the report, then we are not prepared to have the discussion and make recommendations about how to proceed with the WHO vaccine,” she added.”WADA cannot provide a report on its own.”

The World Boxing Organization (WBO) also issued a statement saying it had already begun testing athletes for the new strain of Zika virus.

“I can confirm that WBO is testing more than 100,000 athletes for Zika virus and that WBC has tested some 100,100 athletes and that more than 1,000 of these athletes have tested positive,” it added.WHO says it will test people as soon as possible for the ZIKV strain of disease, but will continue testing people until 2020Dr David Schonfeld said there was no evidence to support the claim that people could stop getting tested.

“When you’re testing a vaccine for a very large population