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Rabies remains an important public health issue in Bolivia, South America. Public concern and fears are most focussed on dogs as the source of rabies. The objective of the present study was to assess immunity of an inactivated suckling mouse brain vaccine against canine rabies used for the official vaccination campaigns under field conditions in an endemic area of rabies in Bolivia. A total of 236 vaccinated and 44 unvaccinated dogs in Santa Cruz de la Sierra, selected using stratified random sampling, were investigated in order to obtain owned dog characteristics and antibody titres against rabies in April 2007. The proportion of vaccinated dogs with an antibody titre exceeded the protection threshold value of 0.5 EU/ml was 58% [95% confidence intervals (CI): 52–65], indicating that vaccination is likely to elicit an antibody response (odds ratio 6.3, 95% CI: 1.2–11.5). The range of geometric mean of antibody titre for vaccinated dogs (0.89 EU/ml; 95% CI: 0.75–1.04) was considered to meet the minimal acceptable level indicating an adequate immune response to the vaccine. However, the titre level was not satisfactory in comparison with the results from other field investigations with inactivated tissue culture vaccines. It is recommended for public health authorities to (1) consider modernizing their vaccine manufacturing method because the level of immunity induced by the current vaccine is comparably low, (2) conduct frequent vaccination campaigns to maintain high levels of vaccination coverage, and (3) actively manage the domestic dog population in the study area, which is largely responsible for rabies maintenance. [ABSTRACT FROM AUTHOR]

The Bolivian government issued a regulation for rabies control in November 2005, owing to increasing the prevalence of dog and human rabies cases in recent years. An assessment of rabies-vaccination coverage and other factors that might influence the success of the on-going vaccination campaign was needed. The objective of this study was to investigate dog rabies vaccination coverage and risk factors associated with dogs being unvaccinated against rabies, and profiles of the owned-dog population in Santa Cruz de la Sierra, Bolivia, where dog rabies was endemic. Mainly due to logistical reasons, the WHO’s expanded programme on immunization cluster-survey method was used. The 390 households were included in the study. Information about dog population and management characteristics was obtained for 542 dogs from 301 households. On average, households had 1.4 dogs and 1.8 dogs per dog-owning household (median = 1). The human-to-dog ratio was 4.6 : 1. During the last 1 year prior to the study, of the 539 dogs aged ≥1 month, 463 (85%; 95% CI 79–91; design effect 3.6) were classified as vaccinated. Amongst the study dogs, dogs aged 1–11 months were the higher risk of dogs not being vaccinated (OR = 8.2; 95% CI 4.3–15.6; P < 0.01). Almost two-thirds of the study dogs were allowed to roam freely throughout the day or in part. Community education efforts should address the importance of dog ownership and movement restriction, and the need to vaccinate young dogs. [ABSTRACT FROM AUTHOR]

In Bolivia, the genealogic registration system is based solely on gestation length (GL) from the last reported AI or embryo transfer (ET) to the date of calving. Some ET calves have been rejected for registration because their GL was more or less than the established 305 d. The objective of this study was to determine the influence of reproductive system (RS), ET, or AI on GL and birth weight (BW) of Nelore cattle in Bolivia. A total of 2,062 observations from three herds over two years in the Bolivian Nelore Cattle Association were analyzed with mixed model procedures. Included in the model were the fixed effects of RS, sex of calf (SX), month of birth (BM), and their interactions. Age of dam was a covariate and sire of calf was considered a random effect. The interaction of BM × RS was significant (P < 0.001) for mean BW. The combination of ET and November BM of calf resulted in greater mean BW (36.4 ± 0.5 kg). Smaller mean BW resulted from the combination of ET and October BM of calf (31.8 ± 3.2 kg). Mean BW of male calves was 2.0 kg greater (P < 0.01) than BW of female calves. Significant effects (P < 0.01) for GL were BM, RS, SX, BM × RS, RS × SX. Cows mated by AI with December calf BM had greater (P < 0.05) GL and cows mated by ET with September calf BM had the shortest (P < 0.05) GL. Of the four RS × SX combinations, cows with male AI calves had the greatest (P < 0.001) GL (297.5 ± 0.8 d) and cows with male and female ET calves had the shortest GL (292.0 ± 0.8 d). Sire effects were important (P < 0.001) for both BW and GL. Correlation of AI and ET with both BW and GL were low (< 0.25 for both). These data show that variation exists for gestation length between AI and embryo transfer births and suggest that the previously determined gestation lengths should be revisited if both AI and embryo transfer calves are to qualify for inclusion in the genealogic registration of the Bolivian Nelore Cattle Association. [ABSTRACT FROM AUTHOR]

Bolivia currently has one of the highest numbers of cases for human and canine rabies and is thus clue to the elimination process. The objective of the present study was to assess antibody seroprevalences against rabies in dogs vaccinated under field conditions and other factors that might influence the success of the on-going rabies control programmes in an endemic area of the disease, Santa Cruz de la Sierra, Bolivia. All 240 study animals, selected using area-stratified random sampling, were investigated in April 2007. Test prevalences were adjusted for the imperfect test characteristics using the Rogan-Gladen estimator (deterministic and stochastic functions) and Bayesian inference. Ninety-four of the tested 240 vaccinated dogs were classified as test-positive for rabies-specific antibodies. With regard to adjusted overall antibody seroprevalence, Bayesian true prevalence estimates (41%, 95% CI: 37-46%) were lower than both of the Rogan-Gladen estimates. The effect of various epidemiological factors on post-vaccination response was also assessed.

The authors analysed laboratory samples testing positive for rabies virus collected between 2000 and 2005 from Santa Cruz de la Sierra, Bolivia, to assess the spatial and spatio-temporal distribution of the endemic of canine rabies. According to the results of the spatial analysis, canine rabies was not evenly distributed in the city. Significant spatio-temporal clustering of canine rabies cases showed a trend towards clusters with high incidence rates in two particular areas compared with surrounding areas in the city. Benefits obtained from each of the analytical techniques utilised are described and practical difficulties in conducting and interpreting the results are discussed.