ena-STUDY-IFIK-08-05-2018-11:13:39:487-1541
Seasonal changes of the nasal microbial diversity of pig farmers
Background: Prior studies have demonstrated an influence of the environment on the human nasal microbiota, particularly in the case of pig farming. However, very little is known about the impact of season on the dynamics of the microbiota in a pig farm setting. Methods: We performed a longitudinal study, investigating the changes in the nasal microbiota of different samples collected in the four seasons (winter, spring, summer and fall). We collected samples from 30 pig farms in Switzerland in each season from 2014-2015. This included nasal swabs from pigs (n=225), air samples taken in the pig confinement building (n=105), and nasal swabs from pig farmers working in these pig farms (n=154 from 48 pig farmers). As controls, nasal swabs from cow farmers (n=56 from 18 cow farmers) and individuals with no contact with farm animals (n=69 from 24 non-exposed individuals) were collected. Analysis of the microbiota was performed based on 16S rRNA high-throughput sequencing utilizing the Illumina MiSeq platform and the recently developed DADA2 pipeline. Results: Alpha-diversity values were generally higher in samples received in winter with the exception of samples from the non-exposed controls which displayed low alpha-diversity values throughout the seasons with no significant differences. The microbial structure of pig farmers, cow farmers and non-exposed individuals was significantly influenced by season. Also, the farm where the samples were taken from influenced the nasal microbiota of pig and cow farmers. There was a stronger similarity for samples that originated from the same farm as compared to samples from different farms in winter and this farm-specificity was partially or completely lost in spring, summer and fall.Conclusions: Nasal microbiota of pig farmers is affected by the regular exposure to pigs throughout the year. However, season has a very strong effect on the nasal microbiota of pig farmers, pigs, and cow farmers, as well as the airborne bacterial composition. This seasonal effect is much weaker in individuals without any contact with farm animals.
Background: Prior studies have demonstrated an influence of the environment on the human nasal microbiota, particularly in the case of pig farming. However, very little is known about the impact of season on the dynamics of the microbiota in a pig farm setting. Methods: We performed a longitudinal study, investigating the changes in the nasal microbiota of different samples collected in the four seasons (winter, spring, summer and fall). We collected samples from 30 pig farms in Switzerland in each season from 2014-2015. This included nasal swabs from pigs (n=225), air samples taken in the pig confinement building (n=105), and nasal swabs from pig farmers working in these pig farms (n=154 from 48 pig farmers). As controls, nasal swabs from cow farmers (n=56 from 18 cow farmers) and individuals with no contact with farm animals (n=69 from 24 non-exposed individuals) were collected. Analysis of the microbiota was performed based on 16S rRNA high-throughput sequencing utilizing the Illumina MiSeq platform and the recently developed DADA2 pipeline. Results: Alpha-diversity values were generally higher in samples received in winter with the exception of samples from the non-exposed controls which displayed low alpha-diversity values throughout the seasons with no significant differences. The microbial structure of pig farmers, cow farmers and non-exposed individuals was significantly influenced by season. Also, the farm where the samples were taken from influenced the nasal microbiota of pig and cow farmers. There was a stronger similarity for samples that originated from the same farm as compared to samples from different farms in winter and this farm-specificity was partially or completely lost in spring, summer and fall.Conclusions: Nasal microbiota of pig farmers is affected by the regular exposure to pigs throughout the year. However, season has a very strong effect on the nasal microbiota of pig farmers, pigs, and cow farmers, as well as the airborne bacterial composition. This seasonal effect is much weaker in individuals without any contact with farm animals.