Demystifying and Demonstrating the Value of a One Health Approach to Parasitological Challenges.

The One Health approach recognizes the interconnectedness of human, animal, and ecosystem health and encourages collaboration between diverse disciplines to address complex health problems. In this paper, 3 academics, with diverse training, experience and backgrounds who each work on different pathogenic parasites, will share their stories of tackling parasitic challenges by applying a One Health approach. The pathogenic parasites to be discussed include the helminth Taenia solium and protozoans Giardia, Theileria, Babesia, Neospora and Toxoplasma species. The 3 narratives focus on research and clinical case-based challenges and illustrate where collaboration between human, animal, and environmental health scientists either has or could lead to improved control of human and animal health as well as important research discoveries. The need for better evaluation of interventions and scientific evidence to support changes in clinical practice and encourage enhanced collaboration between human and veterinary clinicians, as well as new governmental policies to improve public and wildlife health, are described. The need for a range of evidence-based metrics to monitor the success and impact of the One Health approach to veterinary parasitology is also discussed.

Costs and effectiveness of hearing conservation programs at 14 US metal manufacturing facilities.

OBJECTIVE: This study characterised overall and specific costs associated with hearing conservation programmes (HCPs) at US metal manufacturing sites, and examined the association between these costs and several noise-induced hearing loss (NIHL) outcomes. DESIGN: We interviewed personnel and reviewed records at participating facilities. We also measured noise for comparison to the ten-year average of measurements made by each facility. NIHL outcomes assessed included rates of standard threshold shifts (STS) and high-frequency hearing loss, as well as prevalence of hearing impairment, for each participating facility. We used linear regression to identify per-person HCP costs that best predicted the NIHL outcomes. STUDY SAMPLE: We evaluated 14 US metal manufacturing facilities operated by a single company. RESULTS: Annual HCP costs ranged from roughly $67,000 to $397,000 (average $308 ± 80 per worker). Our full-shift noise measurements (mean 83.1 dBA) showed good agreement with the facilities' measurements (mean 82.6 dBA). Hearing impairment prevalence was about 15% overall. Higher expenditures for training and hearing protector fit-testing were significantly associated with reduced STS prevalence. Higher training expenditures were also related to lower hearing impairment prevalence and high-frequency hearing loss rates. CONCLUSIONS: HCP costs were substantial and variable. Increased workplace spending on training and fit-testing may help minimise NIHL.

Modeling risk of occupational zoonotic influenza infection in swine workers.

Zoonotic transmission of influenza A virus (IAV) between swine and workers in swine production facilities may play a role in the emergence of novel influenza strains with pandemic potential. Guidelines to prevent transmission of influenza to swine workers have been developed but there is a need for evidence-based decision-making about protective measures such as respiratory protection. A mathematical model was applied to estimate the risk of occupational IAV exposure to swine workers by contact and airborne transmission, and to evaluate the use of respirators to reduce transmission. The Markov model was used to simulate the transport and exposure of workers to IAV in a swine facility. A dose-response function was used to estimate the risk of infection. This approach is similar to methods previously used to estimate the risk of infection in human health care settings. This study uses concentration of virus in air from field measurements collected during outbreaks of influenza in commercial swine facilities, and analyzed by polymerase chain reaction. It was found that spending 25 min working in a barn during an influenza outbreak in a swine herd could be sufficient to cause zoonotic infection in a worker. However, this risk estimate was sensitive to estimates of viral infectivity to humans. Wearing an excellent fitting N95 respirator reduced this risk, but with high aerosol levels the predicted risk of infection remained high under certain assumptions. The results of this analysis indicate that under the conditions studied, swine workers are at risk of zoonotic influenza infection. The use of an N95 respirator could reduce such risk. These findings have implications for risk assessment and preventive programs targeting swine workers. The exact level of risk remains uncertain, since our model may have overestimated the viability or infectivity of IAV. Additionally, the potential for partial immunity in swine workers associated with repeated low-dose exposures or from previous infection with other influenza strains was not considered. Further studies should explore these uncertainties.