The bacterial community of childcare centers: potential implications for microbial dispersal and child exposure

Spatiotemporal Changes of Antibiotic Resistance, Potential Pathogens, and Health Risk in Kindergarten Dust

The microorganisms present in kindergartens are extremely important for children's health during their three-year preschool education. To assess the risk of outdoor dust in kindergartens, the antibiotic resistome and potential pathogens were investigated in dust samples collected from 59 kindergartens in Xiamen, southeast China in both the winter and summer. Both high-throughput quantitative PCR and metagenome analysis revealed a higher richness and abundance of antibiotic resistance genes (ARGs) in winter (P < 0.05). Besides, the bloom of ARGs and potential pathogens was evident in the urban kindergartens. The co-occurrence patterns among ARGs, mobile genetic elements (MGEs), and potential pathogens suggested some bacterial pathogens were potential hosts of ARGs and MGEs. We found a large number of high-risk ARGs in the dust; the richness and abundance of high-risk ARGs were higher in winter and urban kindergartens compared to in summer and peri-urban kindergartens, respectively. The results of the co-occurrence patterns and high-risk ARGs jointly reveal that urbanization will significantly increase the threat of urban dust to human beings and their risks will be higher in winter. This study unveils the close association between ARGs/mobile ARGs and potential pathogens and emphasizes that we should pay more attention to the health risks induced by their combination.

Environmental microbiome in the home and daycare settings during the COVID-19 pandemic, and potential risk of non-communicable disease in children

An exposure to diverse microbial population early in life is important for the development of immunity against various non-communicable diseases including asthma, childhood leukaemia and other cancers. Social mixing in daycare settings helps with exposure to a variety of microbes. However, social isolation and a high emphasis on workplace hygiene during the COVID pandemic may have affected children's exposure to diverse microbiota. The structure of microbial communities and their role in developing immunity to various diseases are not well understood. In this study, we investigated the structure of microbial communities in daycare and home settings during the pandemic. Interestingly, microbial diversity was relatively higher in dust samples collected from homes, with human-associated taxa being more prevalent compared to those from daycare settings. Environmental microbes were more abundant in dust samples from daycare providers. These results potentially suggest that cleaning practices during the pandemic may have influenced the diversity and microbial abundance of the daycare samples. Several bacterial taxa detected in both the environments are known to induce anti-inflammatory and immunomodulatory responses, conferring protection from various diseases. Therefore, exposure to diverse microbial population in early childhood may play an important role in developing immunity against various non-communicable and infectious diseases.

Enrichment of human nasopharyngeal bacteriome with bacteria from dust after short-term exposure to indoor environment: a pilot study

BACKGROUND

Indoor dust particles are an everyday source of human exposure to microorganisms and their inhalation may directly affect the microbiota of the respiratory tract. We aimed to characterize the changes in human nasopharyngeal bacteriome after short-term exposure to indoor (workplace) environments.

METHODS

In this pilot study, nasopharyngeal swabs were taken from 22 participants in the morning and after 8 h of their presence at the workplace. At the same time points, indoor dust samples were collected from the participants' households (16 from flats and 6 from houses) and workplaces (8 from a maternity hospital - NEO, 6 from a pediatric hospital - ENT, and 8 from a research center - RCX). 16S rRNA sequencing analysis was performed on these human and environmental matrices.

RESULTS

Staphylococcus and Corynebacterium were the most abundant genera in both indoor dust and nasopharyngeal samples. The analysis indicated lower bacterial diversity in indoor dust samples from flats compared to houses, NEO, ENT, and RCX (p < 0.05). Participants working in the NEO had the highest nasopharyngeal bacterial diversity of all groups (p < 0.05). After 8 h of exposure to the workplace environment, enrichment of the nasopharynx with several new bacterial genera present in the indoor dust was observed in 76% of study participants; however, no significant changes were observed at the level of the nasopharyngeal bacterial diversity (p > 0.05, Shannon index). These "enriching" bacterial genera overlapped between the hospital workplaces - NEO and ENT but differed from those in the research center - RCX.

CONCLUSIONS

The results suggest that although the composition of nasopharyngeal bacteriome is relatively stable during the day. Short-term exposure to the indoor environment can result in the enrichment of the nasopharynx with bacterial DNA from indoor dust; the bacterial composition, however, varies by the indoor workplace environment.

BioMateriOME: To understand microbe-material interactions within sustainable, living architectures

BioMateriOME evolved from a prototyping process which was informed from discussions between a team of designers, architects and microbiologists, when considering constructing with biomaterials or human cohabitation with novel living materials in the built environment. The prototype has two elements (i) BioMateriOME-Public (BMP), an interactive public materials library, and (ii) BioMateriOME-eXperimental (BMX), a replicated materials library for rigorous microbiome experimentation. The prototype was installed into the OME, a unique experimental living house, in order to (1) gain insights into society's perceptions of living materials, and (2) perform a comparative analysis of indoor surface microbiome development on novel biomaterials in contrast to conventional indoor surfaces, respectively. This review summarizes the BioMateriOME prototype and its use as a tool in combining microbiology, design, architecture and social science. The use of microbiology and biological components in the fabrication of biomaterials is provided, together with an appreciation of the microbial communities common to conventional indoor surfaces, and how these communities may change in response to the implementation of living materials in our homes. Societal perceptions of microbiomes and biomaterials, are considered within the framework of healthy architecture. Finally, features of architectural design with microbes in mind are introduced, with the possibility of codifying microbial surveillance into design and construction benchmarks, standards and regulations toward healthier buildings and their occupants.