Occurrence of mycobacteria in bovine milk samples from both individual and collective bulk tanks at farms and informal markets in the southeast region of Sao Paulo, Brazil

Background: Mycobacterium spp. is one of the most important species of zoonotic pathogens that can be transmitted from cattle to humans. The presence of these opportunistic, pathogenic bacteria in bovine milk has emerged as a public-health concern, especially among individuals who consume raw milk and related dairy products. To address this concern, the Brazilian control and eradication program focusing on bovine tuberculosis, was established in 2001. However, bovine tuberculosis continues to afflict approximately 1,3 percent of the cattle in Brazil. In the present study, 300 samples of milk from bovine herds, obtained from both individual and collective bulk tanks and informal points of sale, were cultured on Löwenstein-Jensen and Stonebrink media. Polymerase chain reaction (PCR)-based tests and restriction-enzyme pattern analysis were then performed on the colonies exhibiting phenotypes suggestive of Mycobacterium spp., which were characterized as acid-fast bacilli.Results: Of the 300 bovine milk samples that were processed, 24 were positively identified as Mycobacterium spp.Molecular identification detected 15 unique mycobacterial species: Mycobacterium bovis, M. gordonae, M. fortuitum, M. intracellulare, M. flavescens, M. duvalii, M. haemophilum, M. immunogenum, M. lentiflavum, M. mucogenicum, M. novocastrense, M. parafortuitum, M. smegmatis, M. terrae and M. vaccae. The isolation of bacteria from the various locations occurred in the following proportions: 9 percent of the individual bulk-tank samples, 7 percent of the collective bulk-tank samples and 8 percent of the informal-trade samples. No statistically significant difference was observed between the presence of Mycobacterium spp. in the three types of samples collected, the milk production profiles, the presence of veterinary assistance and the reported concerns about bovine tuberculosis prevention in the herds.Conclusion: The microbiological cultures associated with PCR-based identification tests are possible tools for the investigation of the presence of Mycobacterium spp. in milk samples. Using these methods, we found that the Brazilian population may be regularly exposed to mycobacteria by consuming raw bovine milk and related dairy products. These evidences reinforces the need to optimize quality programs of dairy products, to intensify the sanitary inspection of these products and the necessity of further studies on the presence of Mycobacterium spp. in milk and milk-based products. © 2013 Franco et al.; licensee BioMed Central Ltd.

Leukotrienes are not essential for the efficacy of a heterologous vaccine against Mycobacterium tuberculosis infection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anti-Mycobacterium tuberculosis activity of fungus Phomopsis stipata

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Drug resistance in Mycobacterium tuberculosis clinical isolates from Brazil: Phenotypic and genotypic methods

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Synthesis and in vitro anti Mycobacterium tuberculosis activity of a series of phthalimide derivatives

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Thiosemicarbazones, semicarbazones, dithiocarbazates and hydrazide/hydrazones: Anti-Mycobacterium tuberculosis activity and cytotoxicity

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Vanadium complexes with thiosemicarbazones: Synthesis, characterization, crystal structures and anti-Mycobacterium tuberculosis activity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Rapid detection of resistance to pyrazinamide in Mycobacterium tuberculosis using the resazurin microtitre assay

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Synthesis and Anti-Mycobacterium tuberculosis Evaluation of Aza-Stilbene Derivatives

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Spoligotypes of Mycobacterium tuberculosis complex isolates from patients residents of 11 states of Brazil

One of the high tuberculosis (TB) incidence countries in the world, Brazil is characterized by considerable differences in TB incidence on regional and state level. In the present study, we describe Brazilian spoligotypes of 1991 Mycobacterium tuberculosis complex (MTC) clinical isolates from patients residents of 11 states from different regions of the country, diagnosed between 1996 and 2005. By performing spoligotyping on a large number of M. tuberculosis clinical isolates, one of the main objectives of this study was to determine the major genotype families causing TB in Brazil and to verify the region-associated genotype distribution. We observed a total of 577 distinct spoligopatterns, 12.6% of these corresponded to orphan patterns while 87.4% belonged to 326 shared-types (SITs). Among the latter, 86 SITs (isolated from 178 patients) had been observed for the first time in this study, the most frequent being SIT2517 which belonged to the T3-ETH lineage and was exclusively found among patients residents of Belem, the capital of the state of Para (n = 8 isolates). Irrespective of shared-type labeling, a total of 19.5% strains were unique (unclustered) in our study as opposed to 80.5% clustered isolates (189 clusters, size range from 2 to 205 isolates). The three largest clusters were SIT42 of the Latin-America & Mediterranean (LAM) 9 clade (10.3%), SIT53 of the T clade (7.6%), and SIT50 of the Haarlem clade (5.4%). The predominant MTC lineages in Brazil in decreasing order belonged to the LAM (46%); the ill-defined T (18.6%); the Haarlem (12.2%), the X (4.7%), the S (1.9%), and the East African Indian (EAI) (0.85%) families. The rest of clades grouped together as Mycobacterium africanum, Mycobacterium bovis, Beijing, Central Asian (CAS), and the Manu types, represented less than 1% of the strains. Finally, about 15% of the isolates showed spoligotype signatures that were not yet classified among well-defined lineages. In conclusion, we provide hereby a first insight into the population structure of MTC isolates in Brazil, showing the predominance of both LAM and T family and the existence of region-associated genotypes. (C) 2011 Elsevier B.V. All rights reserved.

Assessment of the quality of dna extracted by two techniques from Mycobacterium tuberculosis for fast molecular identification and genotyping

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Comparison of resazurin microtiter assay performance and BACTEC MGIT 960 in the susceptibility testing of Brazilian clinical isolates of Mycobacterium tuberculosis to four first-line drugs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Genotyping of Mycobacterium tuberculosis isolates from alow-endemic setting in northwestern state of Paraná in Southern Brazil

The purpose of this study was to provide information about the genetic diversity and prevalent genotype of Mycobacterium tuberculosis in a low-endemic setting in northwestern state of Paraná in Southern Brazil. We employed spoligotyping and mycobacterial interspersed repetitive units-variable number tandem repeat (MIRU-VNTR) techniques to genotype M. tuberculosisisolates from patients with pulmonary tuberculosis (TB). The 93 isolates analyzed by spoligotyping were divided into 36 different patterns, 30 of which were described in the SITVIT database. Latin American and Mediterranean, Haarlem and T families were responsible for 26.9%, 17.2% and 11.8% of TB cases, respectively. From the 84 isolates analyzed by MIRU-VNTR, 58 shared a unique pattern and the remaining 26 belonged to nine clusters. The MIRU loci 40, 23, 10 and 16 were the most discriminatory. A combination of MIRU-VNTR and spoligotyping resulted in 85.7% discriminatory power (Hunter-Gaston index = 0.995). Thus, combining spoligotyping and MIRU-VNTR typing proved to be most useful for epidemiological study in this low-endemic setting in Southern Brazil. The current study demonstrated that there is significant diversity in circulating strains in the city of Maringá and the surrounding regions, with no single genotype of M. tuberculosispredominating.