a glass of water and magnifying glass. close-up of water microbe

glass water magnifying closeup microbe microbial contamination waterborne pathogen drinking quality safety bacteria realistic chlorination filtration unicellular algae cocci bacilli fungi yeast amoeba paramecium filter pollution clean virus danger waste dirt medical medicine germs environment diarrhea infection laboratory science hygiene protection liquid fluid care analysis disease purity drink studying layer dirty concept pathogenic diversity treatment diseases coli fecal giardia cryptosporidium pseudomonas salmonella helicobacter vibrio cholerae norovirus rotavirus amoebiasis microbiota vector