The Global Effort to Eradicate Rinderpest - International Food Policy ...
vaccine was widely used to great effect in Africa within community-based vaccination programs, particularly in remote areas of Sudan, Somalia, Kenya, Ethiopia, Tanzania, and Uganda as well as in Afghanistan. Because no serological tests exist that can discriminate between vaccination and field infection, rinderpest is currently impossible to detect serologically in the face of ongoing vaccination and for several years after vaccination has ceased. Clearly a marked vaccine with a differentiating test would be of great benefit in the final accreditation stage of the rinderpest eradication program. Development of recombinant vaccines has been described by several groups of scientists (Yilma et al. 1988; Yamanouchi et al. 1993; Romero et al. 1994) using vaccinia or capripox vectors expressing the fusion (F) and hemagglutinin (H) proteins of rinderpest virus, either alone or in combination, and have been shown to be highly efficacious (Ohishi et al. 2000; Verardi et al. 2002). Combined with a differentiating serological test in the form of an enzyme-linked immunosorbent assay (ELISA) based on a baculovirus-expressed rinderpest N protein, a vaccinia recombinant vaccine expressing only F and H rinderpest proteins has been strongly promoted (Yilma et al. 2003). Unfortunately, the N-based ELISA has shown performance characteristics that render it unacceptable as an OIE-prescribed test (OIE 2004) and to date none of the recombinant vaccines have been licensed for general use. An alternative approach has been to explore the production of positively marked vaccines by inserting genes for the expression of jellyfish green fluorescent protein and influenza A hemagglutinin into the Kabete vaccine strain of rinderpest virus (Walsh et al. 2000). The hemagglutinin-marked vaccine retained immunogenicity—and with its companion indirect ELISA to detect the strong hemagglutinin antibody response—appeared to have potential for field use, as did a PPR recombinant vaccine (Diallo et al. 2007). However, none of these recombinant vaccines have been used in vaccination programs and it is unlikely that this will happen now that rinderpest vaccines are no longer routinely used anywhere in the world. 14
4. CAMPAIGNS DESIGNED TO CONTROL OR ERADICATE RINDERPEST FROM ASIA The first major campaigns aimed at eliminating rinderpest began in Asia as the world recovered from World War II. In addition to a coordinated effort that saw rinderpest eliminated by a FAO-supported regional program in support of national efforts across Southeast Asia, two major national campaigns stand out: one in China, which was rapidly successful, and the other in the Indian subcontinent, which took almost 50 years to achieve its target. China During the war period of 1938 to1941 more than 1 million cattle died from rinderpest in western China, and rinderpest spread widely in 1948–49. In 1948 cattle plague was killing millions of cattle, buffaloes, and yaks and the new government decreed that its eradication was to be a priority for it was realized that agricultural development could not occur unless the disease was removed from the equation. An intensive vaccination program was at first constrained in China because early live vaccines retained unacceptable virulence for some breeds of Chinese cattle and yaks. However, passage of the Japanese lapinized vaccine virus in goats and sheep produced a safe attenuated vaccine. Clearing pockets of infection in the Himalayas at a time when there was little or no motorized transport and no refrigeration involved heroic feats. Chinese animal health staff transported the vaccine virus in live, infected sheep on the back of yaks and horses to the sites where the vaccine was produced for immediate use (Figure 1). This campaign had achieved success by 1955, but it was not until 2008 that China was accredited by the OIE as free from rinderpest. Figure 1. Qinghai Animal Husbandry Division staff in 1954 transporting goats on horseback after their inoculation with caprinized vaccine virus. Source: Courtesy of Yang Shibiao. 15
Table A15. Activity multipliers fro
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