Monday, September 19, 2011

Polio in China

As of 13 September 2011, nine cases of polio have been reported in the Xinjiang region.  There has been one death.  All of the cases had wild-type polio 1 (WPV-1) which originated from Pakistan.  Xinjiang shares a border with Pakistan where polio is endemic, along with other neighbouring countries, India, Afghanistan and Tajikistan that are also polio-endemic.

Four children between the ages of four months and 2 years were infected in July, data for the other five are unknown but appear to be all infants, including the one fatality.  This is the first outbreak of polio in China since 1999, when an importation from India was identified.  The last indigenous case was in 1994.  An intense surveillance and vaccination programme has been launched in the region in hopes that the spread can be contained.  However, given that paralytic polio occurs in ~1% of polio cases and of that, 5-10% result in death and there were at least four cases of paralysis and one death, it is more than likely that hundreds, if not thousands of cases have gone undetected.

This outbreak demonstrates the vulnerability of populations who are not adequately vaccinated and the relative ease at which an infectious disease can cause an outbreak even in a country previously certified as polio-free.

1 comment:

  1. It is true, that we have to immunize against Polio-infections until the end game ist over.

    But there are also good news:

    India only confirmed one case of WP3 on 13.1.2011 this year.

    There was only one case of WP3 in whole asia (Pakistan 9.June 2011).

    WP2 as proof of principle was wiped out globally in 1999.

    Now it seems that WP3 is only transmitted in Afrika - where Nigeria is to only endemic country.

    So there is progress at least in India- it may achieve a polio free status in the near future