Brucellosis in Brazil
Introduction
According to the Food and Agriculture Organization (FAO), the World Health Organization (WHO) and the Office International des Epizooties (OIE), brucellosis is still one of the most important and widespread zoonoses in the world.
Brucellosis was first detected in Brazil in 1913 by Gonçalves Carneiro, who reported a case of human brucellosis (Veronezi, 1976). Since then, several epidemiological surveys have revealed the presence of the disease in the livestock population countrywide (Garcia-Carrillo, 1987). Bovine brucellosis due to Brucella abortus is the most prevalent Brucella infection in Brazil, followed by B. suis in pigs. B. melitensis and B. neotomae were never isolated in the country. The economic impact of bovine brucellosis in Brazil has been estimated at 32 millions dollars annually (Brazil, 1971).
Brazil has the largest commercial cattle population in the world with 159.3 million head distributed in 2.5 million holdings that cover in excess of 160 million hectares. The human population of Brazil is estimated at just under 170 million. Table 1 displays the distribution of the livestock population across Brazil’s geographical regions (Brazil, 2000, Brazil, 2000).
The geographical, economical and social conditions account for the existence of very different livestock production systems across the country (Fig. 1). In the north and northeast regions, and in the northwestern part of the midwestern region, cattle are scattered with a density below one animal per hectare. In the southern and southeastern regions and in the eastern part of the midwestern region, cattle production is more intensive with a density above one head per hectare (Brazil, 2000, Brazil, 2000). The zebu breeds predominate in the national beef population, with the exception of the south where European breeds are more common. There is also a growing presence of cross breeds of zebu and European stock.
According to the Ministry of Agriculture (Brazil, 2000, Brazil, 2000), dairy herds account for 20% of the total cattle holdings. Dairy production is concentrated in the southern and southeastern regions, which account for 69% of the national milk production. A great expansion of this activity was recently seen in the midwestern region, which increased its milk production by 50% from 1990 to 1996 and currently accounts for 14.4% of the national milk production. In 1999, the total milk production was 19 billion litres, a 39% increase within a decade (Brazil, 2000, Brazil, 2000).
Section snippets
Bovine brucellosis
Previous studies revealed that bovine brucellosis was widespread throughout the country. In 1977, a national survey showed the following animal prevalence for each region: north 4.1%; northwest 2.5%; midwest 6.8%; southeast 7.5% and south 4.0% (Brazil, 1977).
A few regional surveys revealed that the picture has not changed much since then. In the State of Rio Grande do Sul as a result of a successful vaccination program, animal prevalence dropped from 2.0% in 1977 to 0.3% in 1986. In Santa
Prevention and control
The first attempts to control bovine brucellosis in the country date back to 1940–1950. The proposed measures were restricted to the serological examination of tissues from aborted calves with segregation of reactors and the vaccination with strain 19 (Menezes, 1950, D’Apice, 1954).
After some years and very little progress, new national guidelines were proposed with a view to strengthen control measures. This included vaccination of all heifers with strain 19 and the setting up of brucellosis
Acknowledgements
A.P. Lage is indebted to Conselho Nacional de Desenvolvimento Cientı́fico e Tecnológico-CNPq for the fellowship granted.
References (37)
Prevalência sorológica da brucelose na zona rural do Rio Grande do Sul (Brasil)
Rev. Inst. Med. Trop.
(1978)- Batista, J.A., Hipólito, O., 1960–1961. Estudos sobre a brucelose dos cães. Incidência em Belo Horizonte (Minas...
- et al.
Estudos sobre a etiologia da epididimite ovina no Rio Grande do Sul
Pesqui. Agropecu. Bras.
(1972) - Brazil, Ministério da Agricultura, 1971. Boletim de Defesa Sanitária Animal, Ano V, vols. 1–4, pp....
- Brazil, Ministério da Agricultura, 1977. Diagnóstico de Saúde Animal, c.v, pp....
- Brazil, Ministério da Agricultura, 2000. Boletim de Defesa Sanitária Animal, 30,...
- Brazil, Departamento de Defesa Animal. 2001a. Informações sobre o PNCBET. Brası́lia, Brazil: Ministério da Agricultura...
- Brazil, Secretaria de Defesa Agropecuária, 2001b. Instrução normativa n. 2, 10 Jan 2001b. Diário Oficial, 4 Jun 2001....
- Brazil. Ministry of Agriculture. Department of Animal Health., 2000. Enlargement of the foot-and-mouth disease free...
- et al.
Tipificação de amostras de Brucella suis isoladas no Estado de São Paulo
Arq. Inst. Biol.
(1963)