Human brucellosis at a pig slaughterhouse

doi:10.1016/j.cimid.2013.06.001

Comparative Immunology, Microbiology and Infectious Diseases

Volume 36, Issue 6, December 2013, Pages 575-580

https://doi.org/10.1016/j.cimid.2013.06.001 Get rights and content

Abstract

Seventeen workers in a pig slaughterhouse with signs and symptoms compatible with brucellosis were clinically examined at the outpatient service of different health institutions and studied by serological tests during the period 2005–2011. Eleven blood cultures were taken and six Brucella suis strains were isolated, three biovar 1 and three with atypical characteristics. In order to confirm that these cases had no common source, a variable number of tandem repeat (VNTR) analyses were performed on 5 of the 6 strains whose results showed substantial heterogeneity in the genotypes, thereby demonstrating that the immediate origin was not the same. Two hundred adult pigs admitted for slaughter at the plant were sampled by convenience and tested by buffered antigen plate test (BPAT), serum agglutination test (SAT) and 2-mercapto-ethanol test (MET). Seven of 62 males (11%) and 25/138 (18%) females tested positive. The study results contribute information on risk scenarios for packing plant workers and underscore the need to improve plant workers’ education on appropriate containment measures and to actively screen animals for swine brucellosis.

Introduction

Porcine brucellosis has been detected and identified in Argentina since the 1940s; several studies have mainly focused on establishing the regional prevalence in areas where this animal species was relevant. Sixty-eight percent of the porcine population is found in the provinces of Buenos Aires, Córdoba and Santa Fe, and between 1960 and 1980 several surveys found 14.2–25% prevalence in different regions [1]. However, there is no formal program to monitor the disease [1]. Brucella suis biovar 1 and B. suis biovar 1 with atypical characteristics have been sporadically isolated, but a bacteriological diagnosis is difficult to make in animals because of the cost and the lack of facilities and trained personnel. The serological tests prescribed for international trade are indirect ELISA (IELISA), competitive ELISA (cELISA), fluorescence polarization assay, Rose Bengal test (RBT) and complement fixation test (CFT) [2]. cELISA, RBT and CFT were developed to diagnose individual pigs and to screen large numbers of sera. However, the National Animal Health Service (SENASA) [3] recommends buffered plate antigen test (BPAT), serum agglutination test (SAT) and 2-mercapto-ethanol test (MET) to monitor porcine brucellosis in the country.

Since 1994 the National Laboratories and Institutes of Health Administration Dr. C.G. Malbrán (ANLIS) have been working on the serological and bacteriological diagnosis of human brucellosis. The aim of this paper is to describe cases of workers from a pig slaughterhouse, with signs and symptoms compatible with brucellosis whose diagnoses were confirmed at ANLIS between January 2005 and January 2011, and to report the detection of anti-Brucella antibodies in the pig population entering the processing plant in one day. In order to confirm that the cases had no common origin, a variable number of tandem repeat (VNTR) analyses were performed [4]. The results of this study were partially presented at the 64th Brucellosis Research Conference, Buenos Aires, Argentina, September 21st–23rd, 2011.

Section snippets

Clinical description

This condition is characterized by acute or insidious onset of fever and one or more of the following: night sweats, arthralgia, headache, fatigue, anorexia, myalgia, weight loss, arthritis/spondylitis, meningitis or focal organ involvement (endocarditis, orchitis/epididymitis, hepatomegaly, splenomegaly) [5].

Case classification

Suspicious: A clinically compatible illness, epidemiologically linked to occupational work with animals, consumption of animal products, laboratory exposure, etc. Probable: Suspicious case

Results

During the period of the study, 15 of 17 workers (one woman) with probable brucellosis and signs and symptoms compatible with the disease were confirmed at the ANLIS Brucellosis Service. One case was admitted in 2005, 5 in 2007, 3 in 2008, 2 in 2009, 4 in 2010 and 2 in 2011. Six B. suis strains were isolated from blood cultures, 1/2007; 1/2008; 1/2009, 2/2010 and 1/2011; 3 were biovar 1 and 3 presented atypical characteristics (Table 1). Six workers were referred to us from hospitals where

Discussion

The porcine population in Argentina was estimated at 2,184,804 [13] with 68% located in the humid Pampa region, that includes the provinces of Buenos Aires, Córdoba and Santa Fe. The Northeast region holds 14% of the pig population, the Northwest 4% and the Andean-Southern Cuyo-Patagonia 4% [14]. B. suis infection in pigs is caused mainly by venereal transmission during mating or artificial insemination. It is characterized by infertility and abortion in sows that shed the organism from the

Competing interest

No competing financial interests exist.

Acknowledgements

We are very grateful to Deborah B. Hasan for helpful technical assistance and to Steven Shankster, Amanda Dainty and Gavin Hunter for VNTR studies.

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Occupational exposure to livestock and risk of tuberculosis and brucellosis: A systematic review and meta-analysis
2022, One Health
Occupational diseases are caused by zoonotic pathogens, which spread to humans through various types and intensities of human-livestock contact at work. In the present era, human brucellosis and tuberculosis remain the predominant occupational diseases throughout the world. However, the actual percentage of reported cases that are acquired from various livestock-related occupational groups is not well known. Therefore, we carried out a systematic review and meta-analysis of previous scatter studies mentioned the occurrence of human brucellosis and tuberculosis. From 2000 to 2021, a computer search of PubMed, Science Direct, Google Scholar, BioMed and Scopus was conducted and finally we found 71 studies (brucellosis = 54, tuberculosis = 17), which were included in this meta-analysis to calculate the aggregate prevalence using the random effects model. Moreover, I² statistic, Cochran's Q statistic heterogeneity and subgroup analysis were also performed. The analysis of the data showed that among the various livestock-related occupational groups, the global pooled prevalence of tuberculosis was 19% (95% CI: 09–30), which was higher than brucellosis 14% (95% CI: 10–18). In addition, North America and Africa were reported as the continents of the maximum prevalence rate of 25% (95% CI: −08-58) and 16% (95% CI: 11–21) for tuberculosis and brucellosis than the other continents. Afterwards, the individual's occupation was broken down into the following four groups: farm worker, livestock owner, livestock connected person and abattoir worker. The significant association was found between slaughterhouse workers and brucellosis prevalence (20%; 95% CI: 13–27) as well as the livestock owners and tuberculosis prevalence (28%; 95% CI: 06–50). Likely, a maximum prevalence of tuberculosis was documented among workers ages 20 to 49 years, and of brucellosis among those between the ages of 20 and 25, which suggests that age also had a role. Therefore, it is concluded that the livestock-related occupational groups were found to be at an increased risk of adverse zoonotic disease outcomes. Future studies could be focused on specific occupational group that are in high risk of disease transmission to minimize the effect of these two hazardous pathogens.
Emerging diversity and ongoing expansion of the genus Brucella
2021, Infection, Genetics and Evolution
Remarkable genetic diversity and breadth of host species has been uncovered in the Brucella genus over the past decade, fundamentally changing our concept of what it means to be a Brucella. From ocean fishes and marine mammals, to pond dwelling amphibians, forest foxes, desert rodents, and cave-dwelling bats, Brucella have revealed a variety of previously unknown niches. Classical microbiological techniques have been able to help us classify many of these new strains but at times have limited our ability to see the true relationships among or within species. The closest relatives of Brucella are soil bacteria and the adaptations of Brucella spp. to live intracellularly suggest that the genus has evolved to live in vertebrate hosts. Several recently discovered species appear to have phenotypes that are intermediate between soil bacteria and core Brucella, suggesting that they may represent ancestral traits that were subsequently lost in the traditional species. Remarkably, the broad relationships among Brucella species using a variety of sequence and fragment-based approaches have been upheld when using comparative genomics with whole genomes. Nonetheless, genomes are required for fine-scale resolution of many of the relationships and for understanding the evolutionary history of the genus. We expect that the coming decades will reveal many more hosts and previously unknown diversity in a wide range of environments.
Chronic bacterial infections (II). Brucellosis
2018, Medicine (Spain)
La brucelosis es una zoonosis reemergente ampliamente distribuida en el planeta. Produce una alta morbilidad y pérdidas sociosanitarias muy cuantiosas en los países en los que es endémica.
Producida por coco-bacilos Gram negativos del género Brucella, del cual existen diferentes especies con hospedadores y patogenicidad propias. B. melitensis, B. abortus y B. suis son las especies más frecuentes y B. melitensis la más patógena en seres humanos. Capaz de eludir mecanismos de la respuesta inmune, la infección por Brucella tiene tendencia a producir cuadros prolongados, recaídas y complicaciones focales.
Habitualmente la brucelosis se manifiesta como un cuadro febril sin focalidad aparente, de comienzo agudo o subagudo acompañado de escalofríos, sudoración profusa, artromialgias y malestar general. Aproximadamente, un tercio de los pacientes desarrollará una complicación focal a lo largo del curso evolutivo de la enfermedad. Por lo inespecífico de su espectro clínico, siempre debe intentarse el diagnóstico microbiológico, bien mediante el aislamiento del microorganismo, para lo cual la muestra más rentable es el hemocultivo, o mediante la demostración de anticuerpos específicos a títulos significativos o seroconversión.
El tratamiento más eficaz es doxiciclina 100 mg por vía oral cada 12 horas durante 6 semanas, junto a estreptomicina las primeras 2 semanas. Aunque algo menos efectiva, por su comodidad, doxiciclina junto con rifampicina 600-900 mg/día, ambas durante seis semanas, es una buena alternativa. El tratamiento de las complicaciones focales difiere según la localización y gravedad del caso.
Brucellosis is a re-emerging zoonosis that is widely distributed around the globe. It causes high morbidity and very substantial social and health losses in the countries in which it is endemic.
Caused by Gram-negative coccobacilli of the Brucella genus, of which there are different species with their own hosts and pathogenicity. B. melitensis, B. abortus and B. suis are the most common species and B. melitensis is the most pathogenic in human beings. Capable of eluding immune response mechanisms, Brucella infection tends to cause prolonged symptoms, relapses and focal complications.
Brucellosis routinely manifests with a fever of no apparent focus of infection, of acute or subacute onset accompanied by chills, profuse sweating, arthromyalgia and general malaise. Approximately a third of patients will develop a focal complication as the disease progresses. Because its clinical spectrum is so non-specific, microbiological diagnosis must always be attempted, either by isolating the microorganism, haemoculture is the most cost-effective method, or by demonstrating specific antibodies at significant titres or seroconversion.
The most effective treatment is doxycycline p.o. 100 mg every 12 hours for 6 weeks, combined with streptomycin for the first 2 weeks. And for convenience, although somewhat less effective, doxycycline combined with rifampicin 600-900 mg/day, also for six weeks, is a good alternative. The treatment of focal complications varies according to their location and severity.
MWCNTs functionalization and immobilization with anti-Brucella antibody; towards the development of a nanosensor
2017, Vacuum
Citation Excerpt :
Brucellosis is a chronic infectious zoonotic disease worldwide, which is characterized by infectious abortion and sterility in various domestic animal species and potentially debilitating infection in humans [1–4]. Brucellosis is caused by the facultative intracellular Gram-negative bacteria of the genus Brucella [1,5,6]. There are ten species of Brucella based on preferential host specificity, with three species, Brucella melitensis (mainly infecting goats and sheeps), Brucella abortus (cattle) and Brucella suis (swine) highly pathogenic to humans [7,8].
Brucellosis is endemic worldwide due to the nomadic heritage of drinking fresh milk from goats, sheeps and camels. This study aims at developing an antibody based sensor for the detection of Brucella, wherein the binding of Brucella to the sensor will be detected by measuring the changes in electrical signals via cyclic voltammetric properties. The morphology of the used MWCNTs was observed under SEM, FESEM, and TEM. The MWCNTs (ropes like structure) used for the development of sensor were 2–4 μm in length and ∼10–15 nm in diameter as observed under SEM, FESEM, and TEM. MWCNTs were functionalized via acid treatment/oxidation process and the functional behavior of molecules was confirmed with FTIR spectroscopy. Antibodies were conjugated onto the functionalized MWCNTs using classical EDC coupling reactions. When observed under SEM, binding of Brucella abortus to these anti-Brucella antibody functionalized MWCNTs was clearly observed. Finally, these antibody functionalized MWCNTs were deposited on aluminum sheets for the voltammetric detection of Brucella. Results indicate that the antibody functionalized MWCNTs prepared in this study can be used successfully for the detection of Brucella.
Boar hunting and brucellosis caused by Brucella suis
2017, Travel Medicine and Infectious Disease
Citation Excerpt :
Many of the conditions listed should be considered in the differential diagnosis of an undifferentiated febrile illness in individuals exposed to feral swine (Table 2). Since feral pigs are an indigenous species in many countries, cases of human brucellosis caused by B. suis are reported associated with exposure to feral swine [10,22–25]. In some settings, cases of B. suis remain a concern among populations that participate in pig-farming activities such as in the French Polynesia or by occupational risk at slaughterhouses [24].
Brucellosis remains as a significant public health concern in many areas where the infection persists in domestic hosts (i.e. goats, cattle, and domestic swine) with subsequent risk of transmission to human populations. Brucellosis caused by B. suis remains an important threat to human populations in many countries exposed to domestic and feral swine. In the U.S., swine brucellosis has been under control for many years. Meanwhile, it is a widespread infection among feral swine, particularly in the Southeastern United States; and exposure to infected animals pose a growing threat to humans. We present the case of a 31-year male hunter who six weeks after a knife injury to his hand while field dressing a wild boar, developed a febrile illness associated with hematologic abnormalities and splenic abscesses caused by Brucella suis infection.
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Comparative Immunology, Microbiology and Infectious Diseases

Abstract

Introduction

Section snippets

Clinical description

Case classification

Results

Discussion

Competing interest

Acknowledgements

References (21)

Brucellosis in Argentina

Veterinary Microbiology

Evaluation of Brucella MLVA typing for human brucellosis

Journal of Microbiological Methods

Current understanding of the genetic diversity of Brucella, an expanding genus of zoonotic pathogens

Infection Genetic and Evolution

Terrestrial Manual of Standards for Diagnostic Tests and Vaccines. Porcine brucellosis

Manual de Procedimientos de Establecimientos libres de enfermedad

Identification and characterization of variable number tandem repeat markers for typing of Brucella spp.

Journal of Clinical Microbiology

Ministerio de Salud. Brucelosis. Actualización de la Norma y Procedimientos para la Vigilancia y Control – Tutorial para la Notificación a través del Sistema Nacional de Vigilancia de la Salud (SNVS) C2 y SIVILA. Argentina

The value of serologic tests for diagnosis and follow up of patients having brucellosis

American Journal of Infectious Diseases

Competitive enzyme immunoassay for diagnosis of human brucellosis

Journal of Clinical Microbiology

Genus Brucella. Meyer and Shaw 1920 173AL

Cited by (20)

Occupational exposure to livestock and risk of tuberculosis and brucellosis: A systematic review and meta-analysis

Emerging diversity and ongoing expansion of the genus Brucella

Chronic bacterial infections (II). Brucellosis

MWCNTs functionalization and immobilization with anti-Brucella antibody; towards the development of a nanosensor

Boar hunting and brucellosis caused by Brucella suis

Veterinary Medicine, Eleventh Edition