The Asian strain of Zika has been circulating - presumably at low levels - in Asia for a couple of decades. But unlike we've seen over the past year in the Americas, maternal infection with the virus in Asia has not been linked to congenital defects.
Over the past few weeks, however, we've seen a spike in the number of Zika cases reported in Asia, and concerns it may have led to congenital defects. This from the World Health Organization's Zika Update of Sept 29th.
- Countries in the Western Pacific Region continue to report new cases as seen in Singapore, Philippines, Malaysia and Viet Nam. Thailand, in the South-East Asia Region, has also recently reported Zika cases. Key areas of the response as identified by members of the Association of Southeast Asian Nations (ASEAN) are disease surveillance and risk assessment, relevant and timely sharing of data, regional surveillance and response, vector control, diagnostic testing, laboratory networks and risk communication, and sharing knowledge and best practices. The Ministry of Public Health of Thailand is investigating cases of microcephaly to determine if they may be linked to Zika infection.
- The investigation of microcephaly cases in Thailand is important to determine whether these cases are linked to Zika infection – if found to be linked, these would be the first identified cases of Zika-associated microcephaly in Southeast Asia. If Zika is identified, viral sequencing would be necessary to determine the strain of the virus to determine whether it is a local or imported strain.
Less than 24 hours later, we appear to have an answer. This from Xinhua News.
Two Thai babies confirmed born with Zika-linked microcephaly
Source: Xinhua 2016-09-30 16:08:22
BANGKOK, Sept. 30 (Xinhua) -- Thailand confirmed on Friday that the Zika virus had caused two cases of microcephaly, a condition results in babies being born with small heads, which is the first time microcephaly had been linked to Zika virus in Southeast Asia.
"We have found three infants who are born with microcephaly and two cases are caused by Zika," Prasert Thongcharoen, an adviser to the Department of Disease Control, told reporters in Bangkok, according to Thai media Khaosod.
"As for the third infant, we have not detected the virus until now, " Prasert said, adding that their is still a suspected case of microcephaly in an unborn baby.
He said a team has be set up to look up the mother of the unborn baby and try their best to keep her from being infected with Zika.
The World Health Organization said this was the first Zika-linked microcephaly in Southeast Asia.
Similar reports are available from Reuters and the AP.
It isn't clear at this time is whether these cases indicate that a change has occurred in the virus, making it more virulent, or if birth defects from Zika have occurred all along in Asia, but were at such a low level they we're never linked to the virus.
In either event, Zika in Southeast Asia is rapidly becoming a new front for the battle against the virus.