Posted: March 14th, 2022

Evaluation and Prevention of Methicillin-Resistant Staphylococcus Aureus Airborne Transmission

Evaluation and Prevention of Methicillin-Resistant Staphylococcus Aureus Airborne Transmission in Outdoor Settings and Animal Feeding Operations

Methicillin-resistant Staphylococcus aureus (MRSA) is a type of bacteria that is resistant to many antibiotics and can cause serious infections in humans and animals. MRSA can be transmitted through direct contact with infected people or animals, or through exposure to contaminated surfaces or objects. However, there is also evidence that MRSA can be transmitted through the air, especially in outdoor settings and animal feeding operations (AFOs), where high levels of dust, aerosols, and bioaerosols are present (Gibbs et al., 2006; Smith et al., 2013).

Airborne transmission of MRSA poses a significant threat to public health and animal welfare, as it can increase the risk of infection for workers, visitors, and nearby residents, as well as for livestock and wildlife. Therefore, it is important to evaluate the factors that influence the airborne dissemination of MRSA, and to implement effective prevention and control measures to reduce the exposure and transmission of this pathogen.

Factors Influencing Airborne Dissemination of MRSA

Several factors can affect the airborne dissemination of MRSA, such as the source, the environment, and the receptor. The source refers to the origin of the MRSA bacteria, which can be human or animal carriers, or environmental reservoirs such as soil, manure, or bedding. The environment refers to the physical and biological conditions that influence the survival, transport, and deposition of MRSA in the air, such as temperature, humidity, wind speed and direction, sunlight, vegetation, and microbial communities. The receptor refers to the potential targets of MRSA exposure and infection, such as humans or animals that inhale or ingest the airborne bacteria.

The source, the environment, and the receptor interact in complex ways to determine the likelihood and extent of airborne transmission of MRSA. For example, the amount and type of MRSA bacteria shed by human or animal carriers can vary depending on their health status, colonization site, antibiotic use, hygiene practices, and genetic characteristics (Cuny et al., 2015; Price et al., 2012). The survival and transport of MRSA in the air can depend on the size and shape of the particles or droplets that carry the bacteria, as well as on the environmental factors that affect their stability and movement (Gandara et al., 2017; Hospodsky et al., 2015). The exposure and infection of receptors can depend on their proximity and duration of contact with the source, their susceptibility and immune response to MRSA, and their protective measures such as personal protective equipment (PPE), ventilation systems, or vaccination (Casey et al., 2014; Davis et al., 2011).

Prevention and Control Measures for Airborne Transmission of MRSA

To prevent and control the airborne transmission of MRSA in outdoor settings and AFOs, it is essential to adopt a comprehensive approach that addresses the source, the environment, and the receptor. Some of the possible measures are:

– Reducing the prevalence and shedding of MRSA in human and animal carriers by screening, decolonization, treatment, isolation, quarantine, or culling of infected individuals; limiting or optimizing antibiotic use; improving hygiene practices; and enhancing biosecurity measures (Cuny et al., 2015; Smith et al., 2013).
– Reducing the emission and dispersion of MRSA in the air by modifying animal housing systems; covering or treating manure piles or lagoons; applying dust suppressants or disinfectants; installing filters or scrubbers; planting windbreaks or buffer zones; and monitoring meteorological conditions (Gandara et al., 2017; Hospodsky et al., 2015).
– Reducing the exposure and infection of receptors by educating workers, visitors, and residents about the risks and symptoms of MRSA; providing PPE; improving ventilation systems; implementing infection control protocols; conducting surveillance and reporting; and promoting vaccination (Casey et al., 2014; Davis et al., 2011).

Conclusion

Airborne transmission of MRSA is a potential hazard in outdoor settings and AFOs that can affect human health and animal welfare. To prevent and control this mode of transmission, it is necessary to evaluate the factors that influence the airborne dissemination of MRSA, and to implement effective prevention and control measures that target the source, the environment, and the receptor. Further research is needed to better understand the dynamics and impacts of airborne transmission of MRSA in different settings and scenarios.

References

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Cuny C, Wieler LH, Witte W (2015) Livestock-associated MRSA: the impact on humans. Antibiotics 4: 521–543.

Davis MF, Iverson SA, Baron P et al. (2011) Household transmission of meticillin-resistant Staphylococcus aureus and other staphylococci. Lancet Infect Dis 11: 703–708.

Gandara A, Mota LC, Flores C et al. (2017) Airborne microorganisms from livestock production systems and their relation to dust. Chemosphere 168: 158–170.

Gibbs SG, Green CF, Tarwater PM et al. (2006) Airborne antibiotic resistant and nonresistant bacteria and fungi recovered from two swine herd confined animal feeding operations. J Occup Environ Hyg 3: 699–706.

Hospodsky D, Yamamoto N, Nazaroff WW et al. (2015) Characterizing airborne fungal and bacterial concentrations and emission rates in six occupied children’s classrooms. Indoor Air 25: 641–652.

Price LB, Stegger M, Hasman H et al. (2012) Staphylococcus aureus CC398: host adaptation and emergence of methicillin resistance in livestock. MBio 3: e00305-11.

Smith TC, Male MJ, Harper AL et al. (2013) Methicillin-resistant Staphylococcus aureus (MRSA) strain ST398 is present in midwestern U.S. swine and swine workers. PLoS One 4: e4258.