Bioaerosols in the Barcelona subway system

Abstract

Subway systems worldwide transport more than 100 million people daily; therefore, air quality on station platforms and inside trains is an important urban air pollution issue. We examined the microbiological composition and abundance in space and time of bioaerosols collected in the Barcelona subway system during a cold period. Quantitative PCR was used to quantify total bacteria, Aspergillus fumigatus, influenza A and B, and rhinoviruses. Multitag 454 pyrosequencing of the 16S rRNA gene was used to assess bacterial community composition and biodiversity. The results showed low bioaerosol concentrations regarding the targeted microorganisms, although the bacterial bioburden was rather high (10 bacteria/m ). Airborne bacterial communities presented a high degree of overlap among the different subway environments sampled (inside trains, platforms, and lobbies) and were dominated by a few widespread taxa, with Methylobacterium being the most abundant genus. Human-related microbiota in sequence dataset and ascribed to potentially pathogenic bacteria were found in low proportion (maximum values below 2% of sequence readings) and evenly detected. Hence, no important biological exposure marker was detected in any of the sampled environments. Overall, we found that commuters are not the main source of bioaerosols in the Barcelona subway system.

Detection of Influenza and Other Respiratory Viruses in Air Sampled From a University Campus: A Longitudinal Study

“…However, the detection frequency during the epidemics may be underestimated as no or limited samples were collected during the period, which coincided with the university holidays. A previous study reporting data from bioaerosol sampling at a Barcelona subway also reported a higher detection frequency for influenza-laden aerosols prior to the peak of symptomatic cases in 2013-2014 winter [36]. These results highlight the potential value of applying air sampling as a practical surveillance tool that can be easily implemented at public locations for early detection of impending influenza epidemics.…”

Wastewater pollution differently affects the antibiotic resistance gene pool and biofilm bacterial communities across streambed compartments

“…Only those OTU sharing sequence identity values and alignment coverage values above 98% to listed pathogens were considered for downstream analysis. OTUs showing high sequence identity to well‐known pathogenic bacteria (≥98%) were further classified according to their host and categories related to affectation or pathogenic potential (obligate or opportunistic) as previously described (Triadó‐Margarit et al., ).…”

Station and train surface microbiomes of Mexico City’s metro (subway/underground)

“…Therefore, studies from other networks can be used for reference, but the local diversity will only be understood by directly studying the subways of Mexico City. Multiple studies have characterized the subway microbiomes of various densely populated areas, such as New York City, Boston, Hong Kong, and Barcelona [3][4][5][6][7][8] . Mexico City is one of the most densely populated areas in the world (6,000 people/km 2 in Mexico City; 9,800 people/km 2 in the Greater Mexico City area).…”