POST 00868E : POLIO ERADICATION AND INDIA
Follow-up on Posts 00863E and 00865E
22 December 2005
_____________________________________
The following comment is submitted by Hans Everts (mailto:
[email protected])
from WHO/Geneva.
_____________________________________
When about 95% of the world's population, including 90% of Indian and 50%
of Nigerian population, has not seen polio for a few years or longer, it is
hard to maintain eradication is not technically feasible.
For every high density area with low sanitary standards, low routine
coverage and with ongoing polio transmission, there are several areas with
similar sanitary, demographic or infrastructural characteristics, but
without polio. Think about Bangladesh, Southern Nigeria, the Democratic
Republic of Congo and many others. In Nigeria the population density is
actually higher in the south, where all recent viruses do not represent
indigenous transmission, but importations from the north.
The difference between eradication and elimination is that with the first
the disease disappears, because the pathogenic agent disappears, is
eradicated. With elimination the disease may no longer occur, but its cause
is still there.
The authors present the fact that only 0.5% of polio cases actually develop
paralysis as something that is not widely known. The requirement of a
sufficiently sensitive AFP surveillance is exactly based on that fact as is
the 3 years delay between the last wild virus and certification. In a
setting of good surveillance, circulating virus has never remained
undetected for more than a few months. Longer periods of missed
transmission were only found in areas with major surveillance gaps.
Hans Everts
WHO Geneva
Technical officer EPI
______________________________________________________________________________
______________________
Visit the TECHNET21 Website at
http://www.technet21.org
You will find instructions to subscribe, a direct access to archives, links to reference documents and other features.
______________________________________________________________________________
To UNSUBSCRIBE, send a message to : mailto:
[email protected]
Leave the subject area BLANK
In the message body, write unsubscribe TECHNET21E
______________________________________________________________________________
The World Health Organization and UNICEF support TechNet21. The TechNet21 e-Forum is a communication/information tool for generation of ideas on how to improve immunization services. It is moderated by Claude Letarte and is hosted in cooperation with the Centre de coopération internationale en santé et développement, Québec, Canada (
http://www.ccisd.org)
______________________________________________________________________________