Polio
KABUL — A new vaccine against polio will be used for the first time Dec. 15 in polio immunization campaigns in Afghanistan, according to the World Health Organization.
The bivalent oral polio vaccine (bOPV), recommended by the Advisory Committee on Poliomyelitis Eradication, the global technical advisory body of the Global Polio Eradication Initiative, can provide the optimal protection needed by children against both surviving serotypes (types 1 and 3) of the paralyzing virus.
This will vastly simplify the logistics of vaccination in the conflict-affected parts of this country. This sub-national immunization campaign, from Dec. 15 to 17, will deliver bOPV to 2.8 million children younger than 5 in the southern, southeastern and eastern regions of Afghanistan.
Of the three wild polioviruses (known as types 1, 2 and 3), type 2 has not been seen anywhere in the world since 1999. This achievement led to the development of monovalent vaccines, which provide protection against a single type with greater efficacy than the traditional trivalent vaccine.
To determine whether a bivalent vaccine could effectively protect children living in areas where both types circulate, a clinical field trial completed in June 2009 compared bOPV with the existing vaccines. For both types 1 and 3 polio, bOPV was found to be at least 30 percent more effective than the trivalent vaccine and almost as good as the monovalent vaccines, yet in a package that could deliver both at once.
The bOPV allows countries to simplify vaccine logistics and to optimize protection using a mix of the available polio vaccines according to local needs. In southern Afghanistan, where access to children can be limited depending on the security situation, using bOPV helps maximize the impact of each contact with a child.
Most of Afghanistan is polio-free: 28 out of the 31 children paralyzed by polio this year come from 13 highly insecure districts (of 329 districts in the country). In 2009, polio eradication efforts in Afghanistan have focused on improving operations and creating a safe environment for vaccination teams. Nongovernmental agencies have been contracted and local leaders involved to ensure that parties in conflict are approached, safe passage for vaccinators assured and children reached.
Four countries in the world have never stopped polio transmission — Afghanistan, India, Nigeria and Pakistan. Types 1 and 3 polio circulate in limited parts of all these countries, and the others will follow Afghanistan’s lead in using bOPV during the coming months, marking the adoption of a major new tool in the international effort to eradicate polio.
The availability of bOPV is part of a range of new and area-specific tactics in 2009 to reach eradication more quickly. The swift production of the vaccine was the result of collaboration among the World Health Organization, UNICEF, vaccine manufacturers and regulatory agencies.
The government of Canada finances the vaccination campaign in Afghanistan. Canada, which assumes presidency of the G8 in 2010, first placed polio on the group’s agenda when it last held the presidency in 2002. The G8 is the single-largest donor bloc to polio eradication.
The World Health Organization, Rotary International, the U.S. Centers for Disease Control and Prevention and UNICEF spearhead the Global Polio Eradication Initiative.