Christiane Maria Barcellos Magalhães da Rocha

Human ehrlichioses in Brazil : first suspect cases.

Brazilian spotted fever (BSF) rickettsiosis is the most common and recognized of the human rickettsioses in Brazil. It is difficult to establish the diagnosis of human rickettsiosis infection by routine microbiologic methods, creating a false idea that Rickettsia and Ehrlichia infections are rare and without importance. New tick-borne diseases, like human granulocytic anaplasmosis (HGA) and human monocytic ehrlichiosis (HME), have been described in many countries. These diseases can present symptoms similar to rickettsioses of the spotted fever group, and they are transmitted by ixodid ticks. The first two suspected cases of human ehrlichiosis in Brazil were first considered to be cases of BSF. The differential diagnosis was made at the Minas Gerais Rickettsiosis Public Health Laboratory. The clinical and laboratory findings, with positive serology for the HME agent, indicated suspected cases of human ehrlichioses in Brazil.

Avaliação da qualidade da água e percepção higiênico-sanitária na área rural de Lavras, Minas Gerais, Brasil, 1999-2000

In addition to personal interviews, laboratory analyses were performed using 80 water samples from 45 rural areas that are crossed by the Agua Limpa and Santa Cruz streams close to the city of Lavras, southern Minas Gerais State. The results allowed comparing the quality of water used for agriculture and the identification of determinant factors. The Agua Limpa stream mostly crosses an area used primarily for housing and characterized by low schooling. Many houses are supplied by shallow water wells and have ordinary cesspits for human waste disposal. All springs are polluted. The Santa Cruz stream displays a different scenario. The land is used mostly for agricultural purposes. Most owners live in town, with widely varied levels of school, from none to university. The houses are supplied by surface water. Most of the springs are polluted. The perception by both home and land owners concerning quality of the drinking water is determined solely by the waters physical and organoleptic characteristics. Sanitary parameters are not taken into account. Moreover, there is no relationship between fecal contamination and the type of spring. Land use and anthropic activity are far more important than the type of spring for water quality.

Percepção dos produtores de leite do município de Passos, MG, sobre o carrapato Boophilus microplus (Acari: Ixodidae), 2001

Twenty five dairy farms were randomly chosen from all farms producing more than 500 liters of milk/ day in Passos, MG, Brazil. The owners were interviewed to characterize their perceptions about the biology of B. microplus and their attitudes towards tick control. Most of the producers have a college degree and more than six year-experience in the activity. The biological damages caused by ticks are perceived by the farmers. Their tick control is performed without technical criteria and they did not show a proper knowledge on the biology of B. microplus nor on the toxicological risks of acaricides application. The results reveal a gap between the technology and farmers, favoring tick resistance to acaricides.

Freqüência de anticorpos anti-Neospora caninum em vacas e fetos provenientes de municípios do sul de Minas Gerais

The objective of this study was to determine the frequency of antibodies anti-Neospora caninum in cows and fetuses from Municipalities of southern Minas Gerais. A total of 559 serum samples of cows of the a bank of sera formed from of serum samples collected at 18 dairy farms, distributed for seven Municipalities of the Lavras Micro region, southern Minas Gerais, and 575 serum samples of cows and 503 serum samples of fetuses were collected at slaughter house of Campo Belo, MG. Serum samples were submitted to the indirect fluorescent antibody tests (IFAT), using as antigen taquizoites of N. caninum, and as cut-off values the serum dilution of 1:25 for the fetuses serum and 1:200 for the cows. The frequency in the cows of the Lavras Micro region was of 91.2% (510/559). The frequency was of 97.2% (559/575) and 12.7% (64/503) for females and fetuses from slaughter house, respectively. These results indicate that the infection by N. caninum is endemic in dairy cattle of the Lavras Micro region, southern Minas Gerais, Brazil.

Perceptions about the biology of Rhipicephalus (Boophilus) microplus among milk producers in Divinópolis, Minas Gerais.

One hundred semi-systematized interviews were applied with the aim of surveying the perceptions of milk producers in the municipality of Divinópolis, Minas Gerais regarding the biology of the tick Rhipicephalus (Boophilus) microplus. Content analysis was conducted on each of the variables surveyed and their descriptions, highlighting the higher frequencies in order to construct profiles of perceptions about each of the matters surveyed. In addition, each of the producers was categorized regarding their readiness to proceed with efficient control, from the assessment of their responses. Among the variables surveyed were the tick lifespan, duration of parasitic life, time of greatest incidence, survival in pastures and egg-laying volume. These questions are considered important for defining the knowledge needed for rational combat. It was concluded that the information needed for adopting effective practices to combat ticks was insufficient among the milk farm properties in Divinópolis. Moreover, the producers interviewed had a good perception of what they observed in their daily routine, but did not have complementary information about the tick life cycle.

Perceptions of milk producers from Divinópolis, Minas Gerais, regarding Rhipicephalus (Boophilus) microplus control.

Semi-systematized interviews were conducted with 100 dairy cattle producers in the municipality of Divinópolis, Minas Gerais, with the aim of ascertaining their perceptions regarding the importance of Rhipicephalus (Boophilus) microplus and of combating it. Content analysis was performed and the frequency distribution of each of the variables was used to construct profiles of the producers interviewed. The production losses caused by ticks were perceived incompletely by the producers, who were unaware of the pathogen transmission caused by the parasite and the indirect losses through combating it, such as the cost of acaricide and labor. The combat operations were performed in a traditional manner, with an excessive number of inefficient treatments that aimed to control the level of infestation at that moment. The quality of the acaricide dipping/spraying applied was affected by the quality of the equipment used to apply the products, lack of knowledge of the mode of action of these products, lack of the specific information needed and lack of motivation caused by unawareness of the disadvantages of chemical combat. It was concluded that the lack of knowledge about combat methods and the acceptance of endemicity of the parasitosis were impediments to changing the realities encountered.

Altitudinal Assessment of Amblyomma aureolatum and Amblyomma ovale (Acari: Ixodidae), Vectors of Spotted Fever Group Rickettsiosis in the State of São Paulo, Brazil.

ABSTRACT Amblyomma aureolatum (Pallas) and Amblyomma ovale Koch are common ectoparasites of domestic dogs in São Paulo state, southeastern Brazil, where they are vectors of distinct spotted fever group rickettsioses, one caused by Rickettsia rickettsii (transmitted by A. aureolatum), and the other caused by Rickettsia sp. strain Atlantic rainforest (transmitted by A. ovale). For the present study, we performed an altitudinal assessment of all 1992–2012 records of A. aureolatum and A. ovale retrieved from a tick collection. The municipalities with A. ovale records presented significantly (P < 0.05) lower altitude than the ones with A. aureolatum records; the higher the altitude, the lower the chances for the occurrence of A. ovale and the greater the likelihood for the occurrence of A. aureolatum. Regarding A. aureolatum, the chances of finding it in municipalities between 101 and 700mare nine times higher than in municipalities at ≤ 100 m, or 31.5 times higher in municipalities above 700 m, when compared with municipalities at ≤ 100 m. The reverse was observed for A. ovale, which had its odds ratio diminishing at higher altitudes. These findings have a major role to public health, as A. aureolatum is associated with the transmission of a highly lethal spotted fever (caused by R. rickettsii), whereas A. ovale is associated with the transmission of a milder spotted fever (caused by Rickettsia sp. strain Atlantic rainforest, a R. parkeri-like agent), both in the state of São Paulo.

Seroprevalence for Neospora caninum in goats of Minas Gerais state, Brazil

This study was aimed at determining the prevalence of anti-Neospora caninum antibodies in serum samples from 667 goats, collected from 90 herds in 90 municipalities in eight of the twelve mesoregions of Minas Gerais State. The presence of anti-N. caninum antibodies was determined by IFAT with a cut-off value of 1:50. The true herd-level seroprevalence in the entire study area was 75.2% (CI 95%: 59.5-90.9%). The true individual-level seroprevalence in the entire study area was 10.7% (CI 95%: 8.3-13.4%) with titers ranging from 50 (50.5%) to 3200 (1.7%). The serological evidence from this study indicated that N. caninum infection is widely distributed among goat-rearing herds in Minas Gerais and further studies are needed in order to evaluate the impact of this parasite as a cause of reproductive disorders.

Risk factors associated with seroprevalence of Neospora caninum in dogs from urban and rural areas of milk and coffee production in Minas Gerais state, Brazil

This study was conducted to determine the seroprevalence of anti-Neospora caninum antibodies and to investigate the risk factors related to seroprevalence in dogs from urban and rural areas with distinct economic activities (milk and coffee production) in Minas Gerais state, Brazil. For this purpose, blood samples from 703 dogs were collected and questionnaires addressing epidemiological aspects were completed by dog-owners. The sera were analysed for anti-N. caninum antibodies by indirect fluorescent antibody tests (IFAT ≥ 1:50). Association between epidemiological aspects and seropositivity in dogs was evaluated with multivariate logistic regression models. A total of 80 (11·4%) dogs tested positive for N. caninum. In the multivariate logistic regression models, dogs aged >4 years, dogs used as guard dogs, dogs that spontaneously hunt, and history of bovine abortion were found to be greater risk factors for canine N. caninum infection. When we considered only dogs from rural areas, an association with seroprevalence was seen for milk farms, dogs not fed with commercial food, dogs that hunt, and dogs used as guard dogs.

Occurrences of Eimeria spp. and gastrointestinal nematodes in dairy calves in southern Minas Gerais, Brazil

The aim of this cross-sectional observational study was to determine the frequency and factors associated with infection by Eimeria spp. and gastrointestinal nematodes in 356 calves on 20 dairy farms located in southern Minas Gerais, Brazil. Ten species of Eimeria spp. were identified, of which E. bovis (37.6%) and E. zuernii (17.9%) were the most frequent. From fecal cultures, four genera of gastrointestinal nematodes were recovered, of which Cooperia spp. (74.6%) and Haemonchus (19.4%) were the most frequent. Variables relating to higher levels of technology used on dairy farms showed a significant association (p < 0.05) with higher OPG and EPG counts, and are discussed in this study.