The World Health Organisation is lifting a 9-month emergency declaration, shifting to a long-term response.

The Zika virus and related neurological complications no longer represent a global health emergency, thanks to intensified research during the past months leading to a better understanding of the virus, WHO said in Geneva on Friday.

But the United Nations health agency said the virus remained a serious problem which required a long-term approach.

"WHO's response is here to stay in a very robust manner," WHO's health emergency chief, Dr Peter Salama, said, citing a "significant and enduring" threat.

"We are not downgrading the importance of Zika," Salama said. "We are sending the message that Zika is here to stay and the WHO response is here to stay." 

WHO declared Zika a public health emergency of international concern in February as unproven links emerged to microcephaly, a condition where unborn children develop unusually small brains.

The emergency "was never really meant to try to stop the outbreak," said David Heymann, an epidemiologist who heads the WHO's Zika emergency committee.

Rather, it had been called "so that the world could come together and better understand these extraordinary events of microcephaly that were going on." 

Since it was called, scientists have proven the link between Zika and a rise in such neurological birth defects.

Microcephaly threat

Nearly 30 countries have reported birth defects linked to Zika, with 2,100 cases of nervous-system malformations reported in Brazil alone.  It can cause microcephaly, an abnormal smallness of the head, a congenital condition associated with incomplete brain development.

The virus is spread mainly by mosquitos but can also be transmitted through sex.

Salama said the new phase of fighting the virus required development donors "to step up
to the plate and see this for what it is, which is a long-term problem that the world will have to deal with for many years to come."

"We are sending the message that Zika is here to stay, and WHO's response is here to stay in a very robust manner," Salama confirmed.

Still an emergency 

Ahead of the meeting on Friday, Brazil stated it would continue to treat the Zika outbreak as an emergency.

"We will maintain the emergency (status) in Brazil until we are completely tranquil about the situation," Health Minister Ricardo Barros told journalists.

Officials said incidents of Zika appeared to be decreasing in Brazil but they required more data.

"Last year we didn't have enough tests (to detect Zika), so we can't specify how the virus circulated last year," said Wanderson Oliveira, in charge of emergencies response at the health ministry.

"We don't have a reference to establish whether it is increasing or decreasing," he said.

The decision to end the declaration makes sense in light of the recent drop in new infections, said Dr. Anthony Fauci, the infectious disease chief for the US National Institutes of Health.

But he also noted that Brazil is heading into its hottest months, when mosquito activity peaks, so the outbreak could re-intensify.

"I'm not going to agree or disagree" with the WHO decision, Fauci said. "But if we have another resurgence as we enter into the summer months in the southern hemisphere, they should be ready to re-install it."
 

aw/jm (AP, Reuters, dpa, AFP)