DHAKA: The Southeast Asia Region of the World Health Organization (WHO) comprising 11 countries continues to be polio free.

No child has been afflicted by wild poliovirus since the last case was reported from West Bengal, India, in January 2011.

The countries in the Region are Bangladesh, Bhutan, Democratic People’s Republic of Korea, India, Indonesia, Maldives, Myanmar, Nepal, Sri Lanka, Thailand and Timor-Leste.

They continue to maintain a very high vigil for poliovirus detection. As part of this, environmental surveillance – collection of samples from sewage – is being conducted regularly from 30 sites across seven states in India, said a media statement.

On very rare occasions, vaccine-derived polio viruses (VDPVs) are isolated from sewage samples. Prompt and adequate response to VDPVs detected in the sewage samples in the past has prevented any spread of these viruses in the community.  

It is important to note that such viruses have been detected from environmental samples only – no children have been affected nor cases of paralysis associated.  

Detection of such rare VDPVs is not unusual or unexpected, and robust short- and long-term management strategies are in place to adequately manage the small risks associated with such isolates.

To further mitigate the small risk of VDPVs, globally nearly 155 countries have switched from using the trivalent oral polio vaccine to the bivalent oral polio vaccine.

The switch in April 2016, under the Polio End Game Plan is a critical step to prevent VDPVs and stop all polio, whether due to wild or vaccine-derived viruses.

The South-East Asia Region was certified polio-free on 27 March 2014 and there is no threat to the Region’s polio-free status from the VDPV isolates in the sewage samples.

BDST: 1817 HRS, JUN 18, 2016
MN/BD/RR