Arianne Mastrangeli Amici Santos

Bio: Arianne Mastrangeli Amici Santos is an academic researcher. The author has an hindex of 2, co-authored 2 publications receiving 17 citations.

Prevalence and risk factors for bovine tuberculosis in the State of São Paulo, Brazil

Abstract: A cross sectional study was carried out between May and November 2011 to investigate the epidemiological situation of bovine tuberculosis (bTB) in the state of Sao Paulo, Brazil. The state was divided into seven regions. Three hundred farms from each region, with reproductive activity, were randomly chosen and included as primary sample units. A fixed number of bovine females, older than 2 years of age, were randomly selected and tested, using the comparative cervical tuberculin test. An epidemiological questionnaire based survey was conducted in the selected farms. Our results show that in the state of Sao Paulo, the apparent prevalence of positive farms was 9% (95% confidence interval, 95% CI = 7.8 – 10.5%). The prevalence in the individual regions varied between 3.5% (95% CI = 1.7 ? 6.8%) and 13.9% (95% CI = 10.2 – 18.8%). The apparent prevalence of positive animals in the state was 1.3% (95% CI = 0.9 – 1.7%) and varied from 0.3% (95% CI = 0.2 – 0.6%) to 2.5% (95% CI = 1.4 – 4.5%) in the regions. The risk factors associated with tuberculosis in the state were (i) number of adult females in a herd is ? 24 (Odds ratio, OR = 1.91, 95% CI = 1.32 – 2.75), (ii) type of farm enterprise (dairy: OR = 2.70, 95% CI = 1.40 – 5.21; mixed: OR = 2.03, 95% CI = 1.08 – 3.82), (iii) milking process (milking parlor: OR = 4.12, 95% CI = 1.46 – 11.64; portable milking machine: OR = 2.94, 95% CI = 1.42 – 6.09), and (iv) pasture sharing (OR = 1.58, 95% CI = 1.07 – 2.33). The state of Sao Paulo should implement a structured surveillance system to detect and mitigate the disease. Further, an efficient animal health education program, which encourages the farmers to test replacement animals for bTB prior to introduction in their herds and to avoid pasture sharing with farms of unknown sanitary conditions should also be implemented.

Controlling Bovine Brucellosis In The State Of São Paulo, Brazil: Results After Ten Years Of A Vaccination Program

Abstract: A cross- sectional study was carried out, between May and November 2011, to estimate the situation of the bovine brucellosis in Sao Paulo State, 10 years after the commencement of the vaccination of the heifers with the S19 strain. The State was divided into seven regions and in each of them, 300 farms with reproductive activity were randomly chosen and considered as primary sample units. A fixed number of cows was randomly selected and tested for antibodies against Brucella spp. A farm was considered infected if at least one female tested positive. In the selected farms, an epidemiological questionnaire was administered which focused on herd traits as well as husbandry and sanitary practices that could be associated with the risk of infection. The prevalence (percentile, [95% confidence interval]) of infected herds was 10.2% [8.8-11.8] for the State, and for the regions, it varied from 7.3% [4.7-11.2] to 12.3% [8.8-16.8], not showing significant difference between different regions. The apparent prevalence of positive farms in the State and regions remained similar to the prevalence observed 10 years before. The prevalence of positive animals was 2.4% [1.8-3.1] in the State and varied from 1.1% [0.6-2] to 3.5% [1.7-7.1] in the regions, not showing significant difference between regions. Again, there was no difference in the prevalence of positive animals after 10 years of the vaccination program. The risk factors (odds ratio, 95% confidence interval) associated with bovine brucellosis in the State included number of cows ? 24 (3.08, 2.22-4.27) and the acquisition of breeding animals (1.33, 0.95-1.87). The Sao Paulo State should conduct systematic vaccination coverage of above 80% of the eligible heifers with the S19 strain vaccine annually. Moreover, the State should emphatically use RB51 strain vaccine in females above 8 months of age not vaccinated with S19 strain vaccine. An efficient animal health education program to orientate farmers to test replacement animals for brucellosis prior to introduction in their herds should also be implemented.

Complete Genome Sequencing of Mycobacterium bovis SP38 and Comparative Genomics of Mycobacterium bovis and M. tuberculosis Strains.

Abstract: Mycobacterium bovis causes bovine tuberculosis and is the main organism responsible for zoonotic tuberculosis in humans. We performed the sequencing, assembly and annotation of a Brazilian strain of M. bovis named SP38, and performed comparative genomics of M. bovis genomes deposited in GenBank. M. bovis SP38 has a traditional tuberculous mycobacterium genome of 4,347,648 bp, with 65.5% GC, and 4,216 genes. The majority of CDSs (2,805, 69.3%) have predictive function, while 1,206 (30.07%) are hypothetical. For comparative analysis, 31 M. bovis, 32 M. bovis BCG, and 23 Mycobacterium tuberculosis genomes available in GenBank were selected. M. bovis RDs (regions of difference) and Clonal Complexes (CC) were identified in silico. Genome dynamics of bacterial groups were analyzed by gene orthology and polymorphic sites identification. M. bovis polymorphic sites were used to construct a phylogenetic tree. Our RD analyses resulted in the exclusion of three genomes, mistakenly annotated as virulent M. bovis. M. bovis SP38 along with strain 35 represent the first report of CC European 2 in Brazil, whereas two other M. bovis strains failed to be classified within current CC. Results of M. bovis orthologous genes analysis suggest a process of genome remodeling through genomic decay and gene duplication. Quantification, pairwise comparisons and distribution analyses of polymorphic sites demonstrate greater genetic variability of M. tuberculosis when compared to M. bovis and M. bovis BCG (p ≤ 0.05), indicating that currently defined M. tuberculosis lineages are more genetically diverse than M. bovis CC and animal-adapted MTC (M. tuberculosis Complex) species. As expected, polymorphic sites annotation shows that M. bovis BCG are subjected to different evolutionary pressures when compared to virulent mycobacteria. Lastly, M. bovis phylogeny indicates that polymorphic sites may be used as markers of M. bovis lineages in association with CC. Our findings highlight the need to better understand host-pathogen co-evolution in genetically homogeneous and/or diverse host populations, considering the fact that M. bovis has a broader host range when compared to M. tuberculosis. Also, the identification of M. bovis genomes not classified within CC indicates that the diversity of M. bovis lineages may be larger than previously thought or that current classification should be reviewed.

Epidemiological status of bovine tuberculosis in the state of Rio Grande do Sul, Brazil Situação epidemiológica da tuberculose bovina no Estado do Rio Grande do Sul, Brasil

Abstract: A study was conducted to determine the epidemiological status of bovine tuberculosis in the state of Rio Grande do Sul. The state was divided in seven regions, and in each of them, a pre-established number of farms was randomly sampled. In each farm, cows with age equal to or greater than 24 months were selected at random and submitted to the comparative cervical tuberculin test. The animals whose tests were inconclusive were retested with the same diagnostic procedure within a minimum interval of 60 days. In all, 9,895 animals from 1,067 farms were tested. An epidemiological questionnaire was applied in the farms in order to identify risk factors associated with bovine tuberculosis. The prevalence of infected herds in the state was 2.8% [1.8; 4.0] and that of infected animals was 0.7% [0.4; 1.0]. There was a trend towards a concentration of infected herds in the northern part of the state, with a predominance of dairy and mixed herds. The risk factors associated with the condition of infected herds were being a dairy herd (OR = 2.90 [1.40; 6.13]) and herds with 16 or more cows (OR = 2.61 [1.20; 5.49]). Thus, the best strategy to be adopted by the state is the implementation of surveillance systems to detect and remediate the infected herds, preferably incorporating elements of risk-based surveillance. In addition, the state must carry out a solid action of health education so that the producers test animals for bovine tuberculosis before introducing them in their herds.

Epidemiologic characterization of bovine tuberculosis in the State of Rondônia, Brazil Caracterização epidemiológica da tuberculose bovina no Estado de Rondônia, Brasil

Abstract: A cross sectional study was performed between June 2009 and March 2010 to determine the situation of bovine tuberculosis (bTB) in Rondonia. The state was divided into three regions and, in each of them, 300 farms with reproductive activity were randomly chosen and considered as primary sample units. In the selected farms, an epidemiologic questionnaire was applied. A fixed number of bovine females older than two years of age was randomly selected and tested through comparative cervical tuberculin test. Considering the State of Rondonia, the apparent prevalence of bTB positive farms was 2.3% (95% CI = 1.5-3.5%). The prevalence in the regions varied from 1.7% (95% CI = 0.7 – 4%) to 3% (95% CI = 1.6-5.7%). The apparent prevalence of bTB positive animals in the State of Rondonia was 0.12% (95% CI = 0.06-0.25%) and varied from 0.08% (95% CI = 0.04-0.18%) to 0.15% (95% CI = 0.07-0.33%) in the regions. The risk factor associated to tuberculosis in the State of Rondonia was the acquisition of animals (OR = 7.1; 95% CI = 1.6-31.1). The State of Rondonia should implement a surveillance system to detect bTB-infected herds to certify them as bTB-free. Moreover, an efficient health education program to inform farmers to test replacement animals for bTB prior to introduction in their herds

Analysis of 15 years of the National Program for the Control and Eradication of Animal Brucellosis and Tuberculosis, Brazil Avaliação de 15 anos do Programa Nacional de Controle e Erradicação da Brucelose e Tuberculose, Brasil

Abstract: In 2001, Brazil launched the National Program for Control and Eradication of Animal Brucellosis and Tuberculosis (PNCEBT). After 15 years, After 15 years, it can be checked that there was mistakes and successes in driving the program, but it is undeniable that in this period, a series of structuring actions was initiated. In addition, a large volume of high-quality epidemiological data were produced, which will allow the country to move forward more rationally and safely in combating these two diseases. Today, Brazil have a sufficient contingent of veterinarians to develop the accreditation of farms and vaccination against brucellosis in all States; all batches of vaccines against brucellosis produced by private laboratories are controlled by an official laboratory; the brucellosis vaccination program is well established in most States and it has produced a decrease in prevalence in Mato Grosso, Mato Grosso do Sul, Rondonia and Minas Gerais; there are two ongoing eradication experiences: of brucellosis in Santa Catarina and of tuberculosis in Mato Grosso; nowadays there is a culture to combat brucellosis and tuberculosis in the Brazilian Official Veterinary Services. The epidemiological situation of bovine brucellosis and tuberculosis is well known in the major part of the country. However, progress has been limited by the difficulty in engaging the beef and dairy productive chains as true partners in the process.

Epidemiological Study of Mycobacterium bovis Infection in Buffalo and Cattle in Amazonas, Brazil

Abstract: Bovine Tuberculosis (BTB) is an endemic disease in about one hundred countries, affecting the economy causing a decrease in productivity, condemnation of meat, and damaging the credibility on international trade. Additionally, Mycobacterium bovis the major causative agent for BTB can also infect humans causing a variety of clinical presentations. The aim of this study was to determine BTB prevalence and the main risk factors for the Mycobacterium bovis prevalence in cattle and buffalos in Amazonas State, Brazil. Tissue samples from 151 animals (45 buffalo and 106 cattle from five herds with buffalo only, 22 herds with cattle only, and 12 herds with buffalo and cattle) were obtained from slaughterhouses under State Veterinary Inspection. M. bovis were isolated on Stonebrink medium. The positive cultures were confirmed by polymerase chain reaction (PCR) testing. The apparent herd and animal prevalence rates were 56.4 and 5.40%, respectively. Regarding animal species, the apparent prevalence rates were 3% in cattle and 11.8% in buffalo. Generalized Linear Mixed Models (GLMM) with random effect were used to assess the association with risk factors on the prevalence. Species (buffalo), herds size (>100 animals) and the presence of both species (buffalo and cattle) in the herd were the major risk factors for the infection by Mycobacterium bovis in the region. The findings reveal an urgent need for evidence-based effective intervention to reduce BTB prevalence in cattle and buffalo and prevent its spread to the human population. Studies are needed to understand why buffalo are more likely to be infected by M. bovis than cattle in Amazon. Recommendations for zoning, use of data from the inspection services to generate information regarding BTB focus, adoption of epidemiological tools, and discouragement of practices that promote the mixing of cattle and buffalo, were made.