Occupational exposure to Brucella spp.: A systematic review and meta-analysis

Abstract

Brucellosis is a neglected zoonotic disease of remarkable importance worldwide. The focus of this systematic review was to investigate occupational brucellosis and to identify the main infection risks for each group exposed to the pathogen. Seven databases were used to identify papers related to occupational brucellosis: CABI, Cochrane, Pubmed, Scielo, Science Direct, Scopus and Web of Science. The search resulted in 6123 studies, of which 63 were selected using the quality assessment tools guided from National Institutes of Health (NIH) and Case Report Guidelines (CARE). Five different job-related groups were considered greatly exposed to the disease: rural workers, abattoir workers, veterinarians and veterinary assistants, laboratory workers and hunters. The main risk factors and exposure sources involved in the occupational infection observed from the analysis of the articles were direct contact with animal fluids, failure to comply with the use of personal protective equipment, accidental exposure to live attenuated anti-brucellosis vaccines and non-compliance with biosafety standards. Brucella species frequently isolated from job-related infection were Brucella melitensis, Brucella abortus, Brucella suis and Brucella canis. In addition, a metaanalysis was performed using the case-control studies and demonstrated that animal breeders, laboratory workers and abattoir workers have 3.47 [95% confidence interval (CI); 1.47-8.19] times more chance to become infected with Brucella spp. than others individuals that have no contact with the possible sources of infection. This systematic review improved the understanding of the epidemiology of brucellosis as an occupational disease. Rural workers, abattoir workers, veterinarians, laboratory workers and hunters were the groups more exposed to occupational Brucella spp. infection. Moreover, it was observed that the lack of knowledge about brucellosis among frequently exposed professionals, in addition to some behaviors, such as negligence in the use of individual and collective protective measures, increases the probability of infection.

Accidental exposure to Brucella abortus vaccines and occupational brucellosis among veterinarians in Minas Gerais state, Brazil

“…Indeed, the self‐report of brucellosis in the present study is impaired as the individuals did not identify the major common symptoms of the disease in humans. Furthermore, the results revealed a predominance of indirect methods in the diagnosis of the disease, similar to results reported in a systematic review and meta‐analysis on occupational brucellosis (Pereira et al, 2020), which could be explained by considering the decreased risks and costs of indirect methods compared with bacterial isolation and molecular techniques. Other results that deserve special attention are medical attention and the treatment received among those who reported brucellosis since among the fifty per cent of veterinarians who sought specialized medical care, some were inadequately treated for the disease (Table 2).…”

“…Considering that unprotected contacts with animal biological fluids and live attenuated vaccines pose a greater risk for occupational brucellosis (Pereira et al, 2020), questions regarding protection measures adopted by the participants, PPE adherence and barriers to the non-use of PPE were asked. More than half of the participants reported never wearing mask or goggles, which are considered very important for human brucellosis prevention.…”

“…In this field, veterinary services related to reproduction and vaccination against bovine brucellosis are frequent, which implies that professionals working with dairy and beef cattle have a greater probability of contact with B. abortus, compared with professionals that work in other fields. Considering that unprotected contacts with animal biological fluids and live attenuated vaccines pose a greater risk for occupational brucellosis (Pereira et al, 2020), questions regarding protection measures adopted by the participants, PPE adherence and barriers to the non‐use of PPE were asked. More than half of the participants reported never wearing mask or goggles, which are considered very important for human brucellosis prevention.…”

“…Cattle farmers, slaughterhouse workers, microbiologists, veterinarians and their assistants are often exposed to infected animals, contaminated biological materials or live attenuated anti‐ Brucella spp. vaccines capable of causing the disease to humans (Corbel et al., 2006; Pereira et al, 2020, ). Moreover, these professionals, as well as the general population, can also become infected by non‐occupational transmission route through the ingestion of raw milk and milk products prepared with raw milk (Young, 1995).…”

The epidemiology of bacterial zoonoses in pastoral and dairy cattle in Cameroon, Central Africa

“…The burden of food borne zoonoses is likely significant in SSA countries (Gebreyes et al, 2014), due to limited awareness of the risks posed from consuming animal products (Tebug et al, 2015) and limited implementation of food safety practices (El Zowalaty et al, 2019). Human infections are often associated with individuals with greatest animal contacts such as animal keepers, abattoir workers and those that consume unpasteurized milk (Dadar et al, 2020;Mgode et al, 2015;Pereira et al, 2020;Vanderburg et al, 2014). Bacterial zoonoses such as Brucella abortus (the major Brucella spp.…”