As concern about the outbreak of the Zika virus gathers pace, US researchers have warned that a rapid response is needed to avoid a possible pandemic.
While Zika causes a mild disease in adults, it can have devastating effects on unborn children and has been linked to neurological malformations such as microcephaly. Last year, one of the hotspots for Zika infections – Brazil – reported almost 4,000 cases of microcephaly, a 20-fold increase from 2010.
Brazil has deployed its army to tackle the spread of the infection and in a statement the country’s health minister Marcelo Castro has controversially said the country is “badly losing” its battle against the virus.
With the annual Rio Carnival and Olympics due to take place there in the coming months there are fears of an acceleration in the international spread of Zika.
Lawrence Gostin and Daniel Lucey of Georgetown University write in the Journal of the American Medical Association (JAMA) that, despite lessons learned from the recent Ebola epidemic, the World Health Organization (WHO) “is still not taking a leadership role in the Zika pandemic”.
A failure to act quickly by the WHO – which is briefing member states on the Zika outbreak later today in an extraordinary session at its annual executive board meeting in Geneva – is likely cost thousands of lives during the Ebola outbreak, they claim.
A statement from WHO Director-General Margaret Chan released today acknowledged that the latest outbreak is spreading “explosively,” adding: “the level of alarm is extremely high.”
Zika virus is a mosquito-borne disease transmitted by Aedes aegyptii, the same species that spreads chikungunya, dengue and yellow fever. The virus has been circulating since the 1950s in human populations and is found in Africa, Asia, the Pacific Islands and most recently in the Americas.
As of 23 January 21 countries and territories in the Americas were reporting local transmission of Zika, according to the WHO, indicating rapid geographic expansion of the virus.
With an effective vaccine likely at least three years – and potentially a decade or more – away, governments should focus on clearing still water and other measures to break the mosquito breeding cycle.
Advising the public how to avoid exposure to mosquitoes and stepping up surveillance of Zika cases, is a must, according to Gostin and Lucey, while benefit can also come from advising pregnant women not to travel to Zika hot spots.
The best hope lies however in the development of a vaccine, they note. To that end, the US National Institutes of Health (NIH) launched a Zika vaccine initiative in late 2015 while Brazil has also started vaccine development.
Chan said today that the WHO has decided to convene an Emergency Committee meeting on February 1 to get “advice on the appropriate level of international concern and for recommended measures that should be undertaken in affected countries and elsewhere.”
The agency is also supporting the scale-up and strengthening of surveillance systems in countries exposed or at risk of Zika cases and said it will “prioritise the development of vaccines and new tools to control mosquito populations, as well as improving diagnostic tests.”