Eight
national laboratories constitute the India Poliovirus Laboratory
Network, of which one is functioning as a global specialized
laboratory and two as upgraded national laboratories performing
intratypic differentiation of poliovirus isolates. With the
financial support of Rotary International, NPSP has supplied
all of the laboratories with equipment, consumable supplies
and training of laboratory personnel, so that the heavy specimen
load from India’s AFP cases can be processed efficiently,
accurately and promptly.
The
Indian Polio Lab Network has shown sustained remarkable and
excellent performance in the key WHO programme indicators.
· Accreditation status:
all eight laboratories have passed the most recent on site
review visit and proficiency test panel, which requires
that laboratory virologists and technicians can correctly
identify blind samples that are sent annually from WHO HQ,
Geneva. All laboratories in the network are accredited by
WHO.
· Timeliness: virus
isolation results from stool specimens received in all the
laboratories are available to surveillance programme managers
within 28 days in more than 95% of cases.
All
the national laboratories are isolating poliovirus from the
stool specimens collected from AFP cases by using specific
and transgenic cell lines maintained in the laboratories.
Polioviruses isolated from stool specimens are further tested
for their serotypes (type1, 2 or 3) by a neutralization test
using antisera raised against these serotypes.
If
any poliovirus is isolated from a stool specimen, the reference
laboratories conduct intra-typic differentiation (ITD) of
the isolated virus to determine whether it is a wild type
poliovirus or a vaccine (Sabin) strain.
The Enterovirus Research Centre (ERC), Mumbai has been designated
as one of the seven Global Specialized Laboratories. At
this laboratory, any wild poliovirus that is isolated in
India is sequenced in order to determine the exact genetic
lineage of the virus. This is a powerful tool to determine
the target area of transmission of the poliovirus for programmatic
action and also helps to identify importation and exportation
of polio across borders.
All
the laboratories utilize computerized data management of
stool specimen results and data transmission to the immunization
and surveillance programme managers.
The
India polio lab network is an integral part of the Global Polio
Laboratory Network, and is constantly monitored for accreditation.
All efforts are made by NPSP to support the network.
