host-associated 1,412 digestive tract 1,412 animal host 1,412 intestine 1,389 mammalian host 1,358 human host 993 industrialized 831 adult 369 urban 98 elderly 82 rural 65 non-industrialized 59 child 46 infant 45 rumen 23 adolescent 20 traditional agriculturalist 17 hunter-gatherer 12 anthropogenic 3 aquatic 1 sewage 1 subsurface 1 terrestrial 1 agriculture 1 wastewater 1 medium temperature 1 contaminated 1