Polio outbreak in Yemen grows to 22 cases, UN health agency says

Yemen, polio-free since 1996, now has an outbreak of 22 confirmed cases, and low immunization rates among the children of the Red Sea country may help the spread of the paralyzing virus, the United Nations public health agency said today.

“Four cases of polio were confirmed on 20 April in just one governorate in the south-western part of the country, on the Red Sea coast. The latest 18 cases occurred across five governorates throughout Yemen, including in two districts in the country’s capital, Sanaa, and suggesting that the virus had spread across the country,” the World Health Organization (WHO) said.

Additional cases were suspected in the affected governorates, it added.

WHO said it was firming up plans to follow the mass immunization campaign from 11 to 14 April with a new campaign in late May, using the monovalent oral vaccine type (mOPV1) and covering every Yemeni child younger than 5.

The monovalent vaccine needs fewer doses to provide greater immunity to the type 1 wild virus than does the more commonly used trivalent-OPV, which protects against all three types of wild poliomyelitis virus, it said.

Yemen has been considered at high risk of a polio outbreak since resurgent polio spread to Sudan, with Nigeria accounting for about 60 per cent of the worldwide toll. In February WHO coordinated a mass immunization across 22 African countries.

Global immunization had reduced the annual number of polio cases to 1,267 cases in 2004 from 350,000 in 1988.