Monday, January 21, 2013

Polio Virus Detected By Environmental Surveillance In Egypt



Child receiving Polio Vaccine – CDC PHIL


# 6871



Earlier today a media story of Polio being discovered in Egypt (which has been free of the disease since 2004) began began circulating via several Middle Eastern sources. I’ve held off reporting this until I could find a second source (see below).


First the original report from Pakistan Today.  What wasn’t immediately clear from this report is whether any actual polio infections have been identified in Egypt (they apparently haven’t):


Polio spreads from Pakistan to Egypt


A state of emergency has been declared in Egypt’s Alexandria and Cairo after authorities found spread of polio virus in the two cities, reportedly transferred to the country from Pakistan.


Meanwhile, Prime Minister’s Polio Monitoring Cell in Pakistan has directed all provincial governments to set up polio counters at airports and all internal and external routes across the country.


In a joint statement, World Health Organisation, UNICEF and Polio Monitoring Cell have termed this situation as critical and alarming for the anti-polio campaign in Pakistan.

(Continue . . .)

From AFP we learn that samples of the poliovirus have been detected in sewage samples taken in Cairo, Egypt, and they closely match those found in Pakistan.


Polio virus found in Egypt linked to Pakistan: officials

ISLAMABAD: Pakistani health officials on Monday called for infants leaving the country to be issued polio vaccinations at airports after virus samples linked to a southern Pakistani city were discovered in Egypt.


Two sewage samples from Cairo were analysed and found to resemble a recently discovered strain in the city of Sukkur, a joint statement by health officials, the World Health Organization (WHO) and Unicef said.

(Continue . . . )



Sampling of sewage samples for the poliovirus has increasingly become part of the surveillance effort on polio, since only 1 person in 100 who becomes infected actually develops the acute flaccid paralysis (AFP) we normally associate with the disease.

Everyone who is infected, however, sheds large quantities of the virus in their feces for weeks, making environmental sampling of sewage an efficient method of determining the presence of the virus in the community.


From the Polio Global Eradication Initiative.


Acute Flaccid Paralysis (AFP) surveillance

Nationwide AFP (acute flaccid paralysis) surveillance is the gold standard for detecting cases of poliomyelitis. The four steps of surveillance are:

  1. finding and reporting children with acute flaccid paralysis (AFP)

  2. transporting stool samples for analysis

  3. isolating and identifying poliovirus in the laboratory

  4. mapping the virus to determine the origin of the virus strain.

Environmental surveillance

Environmental surveillance involves testing sewage or other environmental samples for the presence of poliovirus. Environmental surveillance often confirms wild poliovirus infections in the absence of cases of paralysis. Systematic environmental sampling (e.g. in Egypt and Mumbai, India) provides important supplementary surveillance data. Ad-hoc environmental surveillance elsewhere (especially in polio-free regions) provides insights into the international spread of poliovirus.


Vaccination of all children under the age of 5 has been ordered in the regions where the virus has been detected in the environment. 

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