Effectiveness of vaccines and vaccination programs for the control of foot-and-mouth disease in Uganda, 2001–2010

Abstract

Foot-and-mouth disease (FMD) is a highly contagious disease of cloven-hoofed animals. In Uganda, FMD outbreaks are mainly controlled by ring vaccination and restriction of animal movements. Vaccination stimulates immunity and prevents animals from developing clinical signs which include lameness, inappetence, and decreased production. Ring vaccination and restriction of animal movements have, however, not successfully controlled FMD in Uganda and outbreaks reoccur annually. The objective of this study was to review the use of FMD virus (FMDV) vaccines and assess the effectiveness of vaccination programs for controlling FMD in Uganda (2001-2010), using retrospective data. FMD vaccine distribution patterns in Uganda (2001-2010) matched occurrence of outbreaks with districts reporting the highest number of outbreaks also receiving the largest quantity of vaccines. This was possibly due to "fire brigade" response of vaccinating animals after outbreaks have been reported. On average, only 10.3 % of cattle within districts that reported outbreaks during the study period were vaccinated. The average minimum time between onset of outbreaks and vaccination was 7.5 weeks, while the annual cost of FMDV vaccines used ranged from US $58,000 to 1,088,820. Between 2001 and 2010, serotyping of FMD virus was done in only 9/121 FMD outbreaks, and there is no evidence that vaccine matching or vaccine potency tests have been done in Uganda. The probability of FMDV vaccine and outbreak mismatch, the delayed response to outbreaks through vaccination, and the high costs associated with importation of FMDV vaccines could be reduced if virus serotyping and subtyping as well as vaccine matching were regularly done, and the results were considered for vaccine manufacture.

Challenges for Serology-Based Characterization of Foot-and-Mouth Disease Outbreaks in Endemic Areas; Identification of Two Separate Lineages of Serotype O FMDV in Uganda in 2011

“…Moreover, the 60-90% prevalence of antibodies against FMDV NSPs in unvaccinated herds from Bukedea, Isingiro, Kumi and Rakai districts indicates that the sampling took place after considerable spread of the infection within the herds, while the lower seroprevalence consistently observed in herds from Gomba (29%) and Sembabule (24%) districts, as well as in the non-vaccinated herd in Kiruhura (45%), accords with sampling in an earlier phase of the outbreak (Sorensen et al, 1998). The very high prevalence of anti-NSP antibodies in herd Kr.2 in Kiruhura district, which last had an outbreak in 1991 but where the cattle are vaccinated on a yearly basis, may be attributed to repeated use of non-purified vaccines (Sutmoller et al, 2003;Ayebazibwe et al, 2012).…”

Serological and phylogenetic characterization of foot and mouth disease viruses from Uganda during cross‐sectional surveillance study in cattle between 2014 and 2017

“…The circulation of FMDV serotype A in Uganda during 2017 was linked to a strain previously reported in Uganda during 2013. Serotype A has been a rare in Uganda, with only limited evidence of its circulation in the Soroti district in 2002 (Muleme et al, ), and recently in the Wakiso district of Uganda (Namatovu, Tjørnehøj, et al, ). Evidence of this serotype from our study suggests the value of incorporating this serotype into the current vaccine for Uganda; a related prototype strain of serotype A antigen along with the current serotype O, SAT 1, and SAT 2 strains should be considered (Namatovu, Tjørnehøj, et al, ).…”

“…Different control strategies have been implemented in Uganda to mitigate the effects of FMD, including quarantine and vaccination of cattle using imported trivalent vaccines (Muleme et al, ). FMD vaccines used in Uganda are produced in Kenya and Botswana using viruses corresponding to serotypes O, SAT 1 and SAT 2; to the authors' knowledge, vaccine matching with Ugandan field FMDV isolates has not been performed.…”

“…Therefore, vaccines may not provide adequate protection against regionally circulating FMD viruses. For many years, FMD caused by serotype A has been a rare occurrence in Uganda, only observed in Soroti district in 2002 (Muleme et al, ) and in Wakiso district in 2013 (Namatovu, Tjørnehøj, et al, ). As such, imported FMD vaccines in Uganda have historically not contained FMD serotype A.…”

Genetic Diversity of Circulating Foot and Mouth Disease Virus in Uganda Cross-Sectional Study During 2014–2017

“…In this context, the implementation of quarantines and vaccination programs have failed to control FMD in this country (12). Reports indicate that FMD clinical cases increased in Uganda during the 2000's relative to the 1990's (13).…”