WASHINGTON, United States (CMC) — The Pan American Health Organization (PAHO) says the mosquito-borne Zika virus has spread rapidly throughout the Americas, including the Caribbean this year, after it was first detected in Brazil in 2015.

“By the close of this year, 48 countries and territories in the Americas had reported more than 532,000 suspected cases of Zika, including 175,063 confirmed cases. In addition, 22 countries and territories reported 2,439 cases of congenital syndrome associated with Zika. Five countries had reported sexually transmitted Zika cases,” PAHO said.

It said Zika, the first mosquito-borne flavivirus found to be also sexually transmissible and to cause birth defects, spread quickly, noting that before 2015, little was known about Zika apart from reports of earlier small outbreaks in Micronesia and French Polynesia.

“But the outbreak in Brazil’s northeast drew global notice and apprehension as graphic images of newborns with microcephaly, or smaller than normal heads, appeared widely.

PAHO’s Dominica-born Director Carissa F Etienne recounting Zika’s sudden appearance in Brazil in May 2015 and its rapid spread throughout the Americas, noting, “no one could have imagined two years ago that our children would be affected by microcephaly as a result of this once-dormant villain.

“There is a still long way to go on Zika. The development of affordable new tools by the scientific community, including diagnostic tests and a vaccine against Zika, as well as innovation in vector control, is an urgent priority. Our health systems will need to be prepared to ensure such new tools are introduced and that their benefits reach everyone, not merely a few,” she added.

She said in the Americas, “Zika was first confirmed while we were preparing for Ebola and responding to chikungunya.

“It was astute front-line healthcare workers who first realised that they were detecting something unusual. Indeed, our Zika experience proves once again that good clinical judgement and awareness of atypical events are crucial for the timely detection of emerging diseases. It also points to the importance of investing in the health workforce as the first line of defence against emerging disease threats,” she added.

Zika virus disease is caused by a virus that is mainly transmitted by infected female Aedes aegypti mosquitoes but also through sexual intercourse.  People infected by Zika virus usually have mild symptoms that normally last for two to seven days and can include fever, skin rashes, conjunctivitis, muscle and joint pain, malaise or headaches.

There is no specific treatment or vaccine currently available. The virus is now known to circulate in Africa, the Americas, Asia and the Pacific.

PAHO said when clusters of babies with microcephaly and cases of Guillain-Barré syndrome were reported at the same time and place as Zika virus outbreaks, it published a series of alerts starting in December 2015.

Zika spread rapidly not only through the Americas but also to other regions. In all, 75 countries and territories now report evidence of mosquito-borne Zika local transmission since 2007, 12 countries have evidence of person-to-person transmission of Zika virus other than through mosquitoes, and 28 countries have reported microcephaly and other malformations.

Experts now consider Zika to be a long-term public health challenge, following the declaration by the World Health Organisation (WHO) Emergency Committee on Zika that the epidemic’s emergency phase was over.

Coordination and response activities by PAHO and WHO are being folded into longer-term efforts in detection, prevention, care, and support. Further research is underway to strengthen preparedness and response in affected countries.