Human and animal tuberculosis (TB) are primarily caused by Mycobacterium tuberculosis and Mycobacterium bovis, respectively, which are members of the Mycobacterium tuberculosis complex (MTBC) with genetic similarities (Rogall et al. 1990). Zoonotic TB is caused by M. bovis (Weldegebriel et al. 2025). Consequently, it has been reported that out of 10 million people diagnosed with active TB, approximately 140 000 of those cases are estimated to be zoonotic TB cases, with 11 400 deaths recorded worldwide, and the highest incidence recorded on the African continent (Kock et al. 2021). No accurate data are available on zoonotic TB, so it is impossible to estimate the actual disease burden, indicating that cases of humans contracting zoonotic TB might be higher than estimated. Additionally, published data usually do not represent zoonotic TB nationally but typically focus on selected groups (Olea-Popelka et al. 2017). Furthermore, published reports document increased risk of transmission in TB-endemic areas where humans, such as veterinarians and abattoir workers, come into direct contact with infected animals (Cosivi et al. 1998) or with animal products, such as unpasteurised milk (Michel et al. 2015).

Overall, it has been advocated by Adesokan et al. (2013) that the knowledge and practices regarding zoonotic TB could be better investigated in occupationally exposed individuals. Hence, this study analysed the knowledge and practice regarding zoonotic TB by red meat abattoir workers in the Gauteng province of South Africa. Additionally, we assessed their risk of exposure to Mycobacterium spp., including the MTBC, the bacterial agents causing TB, at work, home and outdoor environments.

Most of the respondents in this study were male (84.47%, n = 87/103) and young adults aged 26–35 years old (n = 43/103). This characteristic was also observed in a previous study, where most respondents were young adults. This is probably because of young adults being able-bodied and possessing the physical strength required in abattoir settings (Ismaila, Rahman & Saliluddin 2015). This study found that over 80% of the respondents knew about TB, a frequency much higher than in a previous study conducted in Nigeria. For example, a survey by Kachalla and co-workers found that 53.2% of abattoir workers at two abattoirs in Abuja, Nigeria, had a fair knowledge of the disease (Kachalla et al. 2016). In South Africa, it was previously reported that participants’ bovine TB knowledge was 61% (Marange, Morar-Leather & Fasina 2020), which is lower than that observed in this study. A possible reason for the higher levels of knowledge of TB observed in this study may be partly because of the fact that the research team made both oral and written presentations on zoonotic diseases during earlier visits to the same abattoirs to collect samples from slaughtered livestock, on TB (Mareledwane et al. 2021), brucellosis (Kolo et al. 2019), Q fever and toxoplasmosis (Mangena et al. 2023), and leptospirosis (Dogonyaro et al. 2020). Hence, such interventions are crucial for providing information that can help prevent diseases. It is important to note that a low level of knowledge poses a considerable public health risk, as abattoir workers are in a high-risk occupation for diseases (Dogonyaro et al. 2020). It is pertinent to mention that although the frequency of knowledge of TB in the abattoir workers we studied was high (88.35%), the use of PPE was equally high at 95.15%. It was however, revealed that among this cohort of abattoir workers, there was a gap in their knowledge of aspects of TB such as its transmission. This is because their awareness was comparatively low regarding their ability to transmit the disease to animals (44.6%) or animals’ ability to transmit it to them (45.7%). Future studies may need to explore the definition of knowledge in questionnaire-based studies. Datiko and colleagues found that a lack of transmission pattern awareness is a risk factor, as it leads to disease transmission. In this study, several factors associated with zoonotic TB transmission, such as caring for animals at home and at work, consuming unpasteurised milk, eating uncooked or raw meat, and slaughtering animals at home, were identified as promoting TB transmission (Datiko et al. 2019). Ingestion of raw meat, unpasteurised milk, and contaminated droplets from an infected animal is considered the main route of transmission of TB from animal to human (Sa’idu et al. 2015). This study showed that 25.24% of respondents consumed unpasteurised milk and 10.68% consumed undercooked or raw meat, a concerning finding. This finding is comparable to a study by Mohammed and colleagues in Nigeria, who reported that 24.1% of participants consumed unpasteurised milk (Mohammed et al. 2019). The same study, however, reported a significantly higher percentage of participants (31.2%) who consumed undercooked meat than our study. In Africa, there is an increase in the custom of eating raw meat and unpasteurised milk (Sichewo et al. 2020; Van Helden & Michel 2019) because of cultural and traditional beliefs about their nutritional benefits (Deneke et al. 2022), which is a very unfortunate situation.

Over 40% of abattoir workers in this study slaughter animals at home, which has been identified as an unsafe slaughtering practice. This practice has been among the factors found in some African countries that enhance the transmission of zoonotic TB (Swai, Schoonman & Daborn 2010). Our study revealed that abattoir workers in the age group between 36 years and 50 years old were the most involved in slaughtering livestock at home, hence prone to zoonotic TB infection because of close contact with animals that may be infected (Melaku, Sharma & Alemie 2013).

There was a statistically significant (p = 0.030) difference in the frequency of workers who knew that humans could transmit TB to animals, and this observation was made at the highest frequency in the age group between 26 years and 35 years old (39.02%) compared to 9.76% for workers between the ages of 18 years and 25 years old. These findings were consistent with previous studies that showed that older age was associated with greater knowledge, as older age groups have more work experience than younger ones (Adesokan et al. 2013).

It is also relevant to observe that the differences in the frequency of abattoir workers who previously had symptoms associated with TB were statistically significant (p = 0.009), with 57.14% of workers aged 36–50 years. A total of 18.2% of the workers highlighted that they had a family member previously diagnosed with TB. Respondents who know the signs and symptoms of TB and its transmission are expected to be more likely to practise preventive measures to reduce exposure to the disease (Adebanjo 2011). Other studies have demonstrated that knowledge of TB transmission leads to lower disease prevalence in communities (Sreeramareddy, Harsha Kumar & Arokiasamy 2013; Tschopp et al. 2015).

A limitation of the study was our failure to analyse gender-related percentage frequencies of exposure risk to TB in abattoirs and home environments. It is recommended that this be included in future studies.

The study found that a high percentage (88.35%) of the abattoir workers had knowledge of bovine TB, and 95.15% wore PPE, which augurs well for reducing exposure to the pathogens that cause the disease within the abattoirs in Gauteng province, South Africa. However, the finding that a relatively low proportion of abattoir workers were aware that they could transmit TB to animals (44.6%) and that they could acquire the disease from animals (45.7%) suggests that they may know about the disease but little about its mode of transmission. It is therefore important to emphasise this in future awareness programmes. Considering the risk of exposure to abattoir workers outside the work environment, it is of zoonotic significance that 10.68% of abattoir workers consume uncooked meat, 25.24% drink unpasteurised milk and 47.5% slaughter animals at home, practices that could increase exposure to Mycobacterium spp. including M. bovis. Because abattoir workers are in a high-disease-risk occupation, health authorities, together with abattoir management, should regularly educate them not only about zoonotic TB transmission but also about other zoonotic diseases, such as brucellosis and leptospirosis.