Personal Protective Equipment Use and Handwashing Among Animal Farmers: A Multi-site Assessment

The global seroprevalence of Toxoplasma gondii infection in workers occupationally exposed to animals (1972-2023): a systematic review and meta-analysis

Toxoplasma gondii, a ubiquitous zoonotic parasite infecting warm-blooded animals, poses a significant health threat to workers with occupational animal exposure (WOEA) due to their frequent contact with potential reservoirs. Existing data on T. gondii seroprevalence in the WOEA exhibits substantial global variation. This systematic review and meta-analysis, adhering to PRISMA guidelines, aimed to quantify the global seroprevalence of T. gondii infection among WOEA over the past five decades (1972-2023). We identified 66 eligible studies through a comprehensive search strategy encompassing English publications, with a total sample size of 15,279. A random-effects model with the Freeman-Tukey transformation in STATA v16.0 accounted for the high heterogeneity observed. We estimated the pooled global seroprevalence of T. gondii infection in WOEA at 41% (95% CI: 36-47%). Subgroup analyses revealed significant variations by gender: males (63%) vs. females (37%) (p < 0.05), occupation: non-livestock workers (54%), livestock workers (47%), slaughterhouse workers (44%), and veterinary personnel (27%) (p < 0.05). Geographic trends showed the highest prevalence in Africa (51%), followed by South America (49%), Europe (47%), Australia (43%), Asia (36%), and North America (23%; p < 0.05). Lower prevalence was observed in high-income (39%) and upper-middle-income (38%) countries compared to lower-middle-income (44%) and low-income (48%) countries (p < 0.05). This analysis underscores the high global seroprevalence of T. gondii in the WOEA, highlighting the need for targeted interventions in this high-risk population.

Zoonotic diseases risk perception and infection prevention and control practices among poultry farmers in the Buea Health District, Cameroon: A one health perspective

Background and Aim

Livestock are associated with pathogenic microbes and farm workers play a significant role in the transmission of zoonotic diseases (ZDs). Lack of awareness of exposure risk among farmers may influence their farm practices, thereby enhancing the spread of diseases on farms and to the community. This study was aimed at evaluating the knowledge, risk perception, and prevention and control practices of ZDs among poultry farmers to provide baseline data for establishing a "One Health" practical approach to reducing ZD transmission in poultry farms.

Materials and Methods

Using the exponential discriminative snowball technique, a community-based cross-sectional study involving poultry farmers was carried out in the Buea Health District from April to July 2021. Six feed-producing mills were used as focal points to identify and recruit farmers who were also referred to other farmers. Questionnaires were used to collect data related to participants' knowledge, risk perception, and prevention and control practices of ZDs. Descriptive analyses were performed for all variables while the chi-square test and logistic regression analysis were used to determine associations at 95% confidence level.

Results

In all, 183 poultry farms and 207 workers were enrolled in the study. Despite being aware that animal diseases can be transmitted to humans, most participants showed poor knowledge (54.6%), low-risk perception (51.7%), and poor prevention/control practices (54.1%) on ZDs. The majority did not consider coming in contact with birds' body fluid (blood) or apparently healthy birds to be a risk of infection. More participants with small farms (<500 birds) had low-risk perception of ZDs than those with larger farms (>1000 birds) (p = 0.03). Furthermore, most participants reported practicing hand washing but they neither used protective devices such as gloves and face masks, and >50% would not invite veterinary professionals to their farms. There was a significant association between risk perception and knowledge (p = 0.007; CI = 1.257-4.200) as well as between risk perception and prevention/control practice (p = 0.002; CI = 1.451-4.867).

Conclusion

Poultry farm workers in Buea had poor knowledge and perception of ZD risk and this might have contributed to their poor prevention/control practices on the farms. Enhanced informal education of poultry farmers through training workshops and seminars will improve their knowledge and skills on ZD transmission risk and prevention.

Serological Evidence of Hepatitis E Virus (HEV) Infection Among Ruminant Farmworkers: A Retrospective Study from Malaysia

Background

As scant data are available about Hepatitis E virus (HEV) infection in Malaysia, this study aimed to determine the seroprevalence of HEV amongst ruminant farmworkers in Malaysia.

Methods

A total of 87 farmworkers provided serum samples, which were collected from eight farms. All serum samples were tested for anti-HEV IgG and anti-HEV IgM by an enzyme-linked immunosorbent assay (ELISA) using the Wantai HEV-IgG and HEV-IgM ELISA kits from Beijing Wantai Biological Pharmacy Enterprise Co., Ltd, Beijing, China.

Results

Farmworkers from six cattle farms, one sheep farm and one goat farm were investigated in this study. Only one farm practices zero-grazing, with the rest using rotational grazing. Of the 87 farmworkers, males comprised 83.9%, and almost half (47.1%) were aged 20-35 years old. By ethnic group, the vast majority were Malay. Most of the farmworkers have good hygiene practices; washing or changing their clothes and showering after dealing with farm animals were common. None of the farmworker serum samples had anti-HEV IgM and IgG detected (95% confidence interval (CI): 0, 0.0415).

Conclusion

The finding suggests that the farmworkers had no previous exposure to Hepatitis E, and were not at risk of occupational exposure to HEV infection. Our findings suggest that a zero seroprevalence of HEV infection among ruminant farmworkers in the Muslim majority country. Good farm management, hygiene practices and the absence of contact with swine-related contamination might have contributed to the no or minimal zoonotic risks of HEV amongst farmworkers surveyed in this study.

Personal protective equipment use during industrial hog operation work activities and acute lung function changes in a prospective worker cohort, North Carolina 2014-2015

INTRODUCTION

Occupational activities related to industrial hog operation (IHO) worker lung function are not well defined. Therefore, we aimed to identify IHO work activities associated with diminished respiratory function and the effectiveness, if any, of personal protective equipment (PPE) use on IHOs.

METHODS

From 2014 to 2015, 103 IHO workers were enrolled and followed for 16 weeks. At each biweekly visit, work activities and PPE use were self-reported via questionnaire and lung function measurements were collected via spirometry. Generalized linear and linear fixed-effects models were fitted to cross-sectional and longitudinal data.

RESULTS

Increasing years worked on an IHO were associated with diminished lung function, but baseline and longitudinal work activities were largely inconsistent in direction and magnitude. Unexpectedly, a -0.3 L (95% confidence interval: -0.6, -0.04) difference in forced expiratory volume in the first second (FEV₁ ) was estimated when workers wore PPE consistently (≥80% of the time at work) versus those weeks they did not. In post-hoc analyses, we found that coveralls and facemasks were worn less consistently when workers experienced worse barn conditions and had more contact with pigs, but coveralls were worn more consistently as cleaning activities increased.

CONCLUSIONS

Similar to past studies, baseline estimates were likely obscured by healthy worker effect bias, but showed decrements in worker lung function as years of work increased. A challenge to disentangling the effect of work activities on lung function was the discovery that IHO workers used PPE differently according to the work task. These data suggest that interventions may be targeted toward improving barn conditions so that workers can consistently utilize IHO-provided PPE.

Clostridioides difficile on dairy farms and potential risk to dairy farm workers

Clostridioides difficile causes severe colitis in people and is a significant enteric pathogen in many species of animals, including swine, horses, and potentially cattle. C. difficile is shed in feces, and transmission occurs horizontally via the fecal-oral route. Livestock has been suggested as a potential reservoir for C. difficile, and while studies have shown that swine and farm workers can be colonized with identical clones of C. difficile, the zoonotic transmission of C. difficile from livestock to people has not been definitively demonstrated. The goal of this study was to determine whether dairy calves and dairy farm workers harbored genetically similar isolates of C. difficile. First, we validated a glove juice protocol for detecting C. difficile on farm workers' hands. We then visited 23 farms and collected 1) fecal samples from 92 dairy calves, 2) hand rinsates from 38 dairy farm workers, and 3) fecal samples from five of the dairy farm workers who were willing to submit them. All samples underwent anaerobic culture and qPCR to detect C. difficile. C. difficile was detected on 15 of the farms (65.2%, 95% confidence interval (CI) 42.7%-83.6%) and in 28 calves (30.4%, 95% CI 21.2-40.9%) but in none of the hand rinsates or human fecal samples. Thus, the zoonotic transmission of C. difficile on dairy farms could not be demonstrated, and dairy farmers did not appear to be at increased risk of acquiring C. difficile via the fecal-oral route.

The use of personal protective equipment during common industrial hog operation work activities and acute lung function changes in a prospective worker cohort, North Carolina, USA

Introduction

As occupational activities related to acute industrial hog operation (IHO) worker lung function are not well defined, we aimed to identify IHO work activities associated with diminished respiratory function and the effectiveness, if any, of personal protective equipment (PPE) on IHOs.

Methods

From 2014-2015, 103 IHO workers were enrolled and followed for 16 weeks. At each bi-weekly visit, lung function measurements were collected via spirometry and work activities and PPE use were self-reported via questionnaire. Generalized linear and linear fixed-effects models were fitted to cross-sectional and longitudinal data.

Results

At baseline, increasing years worked on an IHO were associated with diminished lung function, but other activities were less consistent in direction and magnitude. In longitudinal models, only reports of working in feeding/finisher barns, showed a consistent association. However, a -0.3 L (95% confidence interval: -0.6, -0.04) difference in FEV ₁ was estimated when workers wore PPE consistently versus those weeks they did not. In post-hoc analyses, we found that coveralls and facemasks were worn less consistently when workers experienced worse barn conditions and had more contact with pigs, but coveralls were worn more consistently as cleaning activities increased.

Conclusions

Similar to past studies, baseline estimates were likely obscured by healthy worker bias. Also making it challenging to disentangle the effect of work activities on lung function was the discovery that IHO workers used PPE differently according to work task. These data suggest that interventions may be targeted toward improving barn conditions so that workers can consistently utilize IHO-provided PPE.

KEY MESSAGES

What is already known about this subject?: Working on industrial hog operations may be deleterious to long- and short-term respiratory health due to airborne bacteria, endotoxin, hazardous gases, dust, and dander in barns. In efficacy studies PPE has been shown to be protective, but studies have shown that PPE utilization among hog workers has historically been sub-optimal.What are the new findings?: As barn conditions worsened and contact with pigs increased, workers in this cohort reported wearing coveralls and face masks less often; however, they reported increased PPE use as they conducted more cleaning activities at work. During weeks when workers wore PPE their lung function declined, a possible cause being the improper use of the equipment leading to a false sense of protection or re-exposure to hazardous contaminants.How might this impact on policy or clinical practice in the foreseeable future?: Given COVID-19, the H1N1 "swine flu" pandemic, our knowledge of antimicrobial resistant pathogens, and increasing awareness about how food systems are linked to the spread of emerging infectious diseases, occupational health intervention research and workplace policies may focus on creating barn environments that are more conducive to PPE use which could help protect workers and consequently the community.

Facemask Alternatives in Veterinary Medicine in the Context of COVID-19 Shortages

The COVID-19 pandemic has caused a widespread shortage of facemasks and other personal protective equipment in veterinary medicine without clear, research-based guidance on alternatives to FDA-certified disposable surgical masks. In the absence of detailed veterinary research, an in-depth review of the human medical literature was conducted to evaluate the viability of reusable, sterilizable cloth, medical textile, or other material alternatives that may be quickly manufactured and used by veterinarians. The results at the time of publication support the AVMA, CDC, and WHO recommendations to extend use, reuse, and resterilize facemasks before considering using a homemade facemask. Pending further research, or until and unless the FDA certifies a reusable homemade mask or design, the substitution of homemade masks for FDA-certified surgical masks should only be considered as a last resort. Most homemade masks are not suitable replacements for N95 FFRs. If a homemade facemask must be made, the following materials and testing guidelines are suggested:

- densely woven cotton fabric (≥270 thread count), medical textile, or other impermeable, breathable material that can be laundered and resterilized

- make pleated or fitted pocket style facemasks to maximize fit

- make masks with two sets of ties, not elastics, to endure laundering and autoclaving

- internal wire or fabric tape may be used to mold masks over the nose

- filter material should be designed for use near mucus membranes, such as facial tissue or paper towel

- if possible, fit test homemade masks against an FDA-certified surgical mask as a control

- if higher filtration efficiency is required, test according to the FDA Enforcement Policy for Face Masks and Respirators During the Coronavirus Disease (COVID-19) Public Health Emergency

- Maintain enough masks to change as frequently as one would change disposable surgical masks to maintain appropriate hygiene.

Health Literacy Toward Zoonotic Diseases Among Livestock Farmers in Vietnam

BACKGROUND

Zoonoses are an increasing concern worldwide, particularly in low- and middle-income countries. People with close contact with animals are at high risk for contracting and transmitting the zoonotic diseases.

OBJECTIVES

To determine health literacy of livestock farmers toward biosecurity to prevent zoonotic diseases.

METHODS

This cross-sectional mixed-methods study was conducted in Thai Nguyen Province, Vietnam, where livestock and farming are the main occupation. The questionnaire survey was submitted to 218 farmers who have close contact with livestock. In addition, 8 farmers were invited to an in-depth interview to further explore the health literacy.

RESULTS

Half of the participants were men. The average age (standard deviation) of the participants was 49.3(11.5) years. The median years with experience in farming was 15 years. The majority (82.0%) of the participants had moderate health literacy level regarding zoonoses. Improper use of antibiotics was referred by 58.0% of participants, including antibiotic use as feeding supplements (34.0%) and the use of human antibiotics to treat sick animals (24.0%). Many participants were unaware of zoonotic prevention measures and due to this had practices such as not wearing protective equipment (60.0%), an absence of acaricides to prevent vector infestations (52.0%), an absence of disinfection measures (42.0%), low rate of rabies vaccination (54.0%), and do not quarantining sick animals (38.0%). In-depth interviews revealed great concern among farmers about a collective lack of participation from local veterinarians, health workers, and government authorities in zoonoses-prevention efforts. Statistical models showed that farm scale, ethnic groups, and perceived income were associated with the overall health literacy about zoonoses.

CONCLUSION

Comprehensive health education related to zoonotic diseases is recommended to improve overall knowledge, including routes of transmission, symptoms and consequences of diseases, and antibiotic usage. In addition, guidance should be provided to farmers on how to treat sick animals, the appropriate use of antibiotics, and waste management. Local veterinarians and health workers are important contact points and should work closely with the farmers to prevent zoonotic diseases.

Understanding attitude, practices and knowledge of zoonotic infectious disease risks among poultry farmers in Ghana

Zoonotic infectious diseases (ZIDs) are increasing globally, and livestock farmers in low‐ and middle‐income countries are at particularly high risk. An evaluation of farmer's behaviour on farms can be used to identify the risk factors and to develop tailored control strategies. This study documents the knowledge of zoonotic poultry diseases (ZPD) among 152 poultry farm workers (respondents) from 76 farms in the Ashanti region of Ghana and assessed their on‐farm attitude and practices that increase their risk to exposure of ZPD. The median age of respondents was 29 years, 91.4% (n = 139) had a formal education, and 80.9% (n = 123) had worked on the farm for more than 1 year. The majority of farms (n = 69, 90.8%) had multiple flocks and 27.6% (n = 21) kept other animals, of which 57.1% (n = 12) were pigs. The majority of respondents had good knowledge about poultry diseases but not about ZPD. A higher level of education and longer work experience improved respondents’ knowledge of poultry and ZPD. Although respondents identified the wearing of personal protective equipment (PPE) as a major ZPD preventive measure, the majority did not put that knowledge into practice. Most farms (71.1%, n = 54) had no footbath and 55.3% (n = 42) deposited farm‐waste on the farm. While 97.4% (n = 148) of respondents washed their hands after working, only 48.7% (n = 74) wore protective footwear, 2.7% (n = 4) wore overalls, 2% (n = 3) wore nose masks and none (n = 0) wore gloves. The husbandry practices and attitude of farmers expose them to pathogens on the farm and increase their risk of becoming infected with ZPD in the sub‐region. The results from this study could be used to promote human health among farm workers in Ghana.

Protective practices against zoonotic infections among rural and slum communities from South Central Chile

BACKGROUND

Despite well-recognized recommendations to reduce human exposure to zoonotic pathogens, the use of personal and herd-level protective practices is inconsistent in communities where human interactions with animals are common. This study assessed household-level participation in rodent- (extermination, proper food storage, trash disposal), occupational- (preventive veterinary care, boot-wearing, glove-wearing), and garden-associated (restricting animal access, boot-wearing, glove-wearing) protective practices in farms, villages, and slums in the Los Rios region, Chile, where zoonotic pathogens are endemic.

METHODS

Questionnaires administered at 422 households across 12 communities recorded household-level socio-demographic characteristics and participation in nine protective practices. Household inclusion in the analysis of occupational practices required having livestock and a household member with occupational exposure to livestock (n = 127), and inclusion in analysis of garden practices required having a garden and at least one animal (n = 233). The proportion of households participating in each protective practice was compared across community types through chi-square analyses. Mixed effects logistic regression assessed household-level associations between socio-demographic characteristics and participation in each protective practice.

RESULTS

Most households (95.3 %) reported participation in rodent control, and a positive association between the number of rodent signs in a household and rodent extermination was observed (OR: 1.75, 95 % CI: 1.41, 2.16). Occupational protective practices were reported in 61.8 % of eligible households; household size (OR: 1.63, 95 % CI: 1.17, 5.84) and having children (OR: 0.22, 95 % CI: 0.06, 0.78) were associated with preventive veterinary care. Among eligible households, 73.8 % engaged in protective practices when gardening, and species diversity was positively associated with wearing boots (OR: 1.27, 95 % CI: 1.03, 1.56). Household-level participation in all three protective practices within any exposure category was limited (<10.4 %) and participation in any individual protective practice varied considerably within and across community types.

CONCLUSIONS

The levels of participation in protective practices reported in this study are consistent with descriptions in the literature of imperfect use of methods that reduce human exposure to zoonotic pathogens. The wide differences across communities in the proportion of households participating in protective practices against human exposure to zoonotic pathogens, suggests that future research should identify community-level characteristics that influence household participation in such practices.