Overnight, World Health Organisation Director-General Margaret Chan declared the outbreak of Zika virus a public health emergency. So what does this mean?

This is the fourth time the WHO has declared a state of emergency. The first was in 2009 for the H1N1 virus. The second and third were in 2014 for outbreaks of polio and Ebola.

Headlines declaring this news might sound alarmist but this is not the WHO’s intention. The alert is a political tool, to bring attention to people all over the world that this is an issue of concern.

It’s estimated there are more than four million people living in areas populated by the Yellow Fever mosquito, which is responsible for spreading the disease. We need to communicate the risks to these people. We need the global community to get on board to aid in control efforts in South America and the other areas affected by the Zika virus.

In particular, this is an opportunity for expertise to be shared across the globe, for research money to be directed to diagnostics and vaccine development and for an increase in international aid money required to control mosquito populations in some of the poorer affected countries.

Declaring Zika virus a public health emergency has happened relatively early in the outbreak compared to the comparable declaration for Ebola virus. But this simply reflects the acknowledged need by the world community to deal with these emergencies more quickly.

The emergency alert is also a call to arms to focus on research in this area, particularly to establish a causal link between the Zika virus and the reported subsequent birth defects, especially microcephaly (reduced head size and brain damage).

The WHO’s briefing overnight made clear that the emergency of international concern is not for Zika itself, but for the cluster of microcephaly cases and its suspected link to the Zika virus.

As the WHO pointed out, Zika itself is not a clinically serious condition.

The US has added Zika virus to its research agenda. The affected countries within the Global Research Collaboration for Infectious Disease Preparedness, a body of infectious disease experts and funders, are meeting this evening to discuss what resources can be diverted to help in diagnostic and vaccine development.

Read more: Does Zika pose a threat to Australia?

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