[bac.te.ria] n, pl -ri.as [pl. of bacterium] (1884): a group (as a genus, species, or strain) of bacteria--used chiefly in nontechnical writing and in news broadcasts usage Bacteria is regularly a plural in scientific and pedagogical use; in speech and in journalism it is also used as a singular "caused by a ~ borne by certain tiny ticks --Wall St. Jour." "more resistant to chlorine and elevated water temperatures than other ~s --Allan Bruckheim, M.D., Chicago Tribune". This journalistic use is found in British as well as American sources.
BACTERIA
Meaning of BACTERIA in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012