Two water-borne bacteria that cause diarrhoea and gastroenteritis don't show up in the Bureau of Indian Standards (BIS) tests.
The microbiology department of Punjab Agricultural University (PAU) detected the emerging pathogens in the water samples tested in its laboratory in 2007. However, the BIS is yet to upgrade its tests to reveal the microbes.
Aeromonas hydrophila and Yersinia enterocolitica, detected during epidemiological surveillance in Ludhiana district, are dangerous enemies. "The bacteria were in the water samples collected from sources such as municipal facilities, submersible pumps and hand pumps," Dr Param Pal Sahota, PAU's senior microbiologist. "We then developed a testing kit for the two new bacteria as well. Further research is on," Dr Sahota said.
The BIS should modify its water tests to present conditions, says Dr Sahota. At present, it doesn't look for Aeromonas hydrophila and Yersinia enterocolitica in water, and has tests that focus on the presence of E.coli bacteria alone. The PAU came across water samples that contained the new bacteria but no E.coli.
The new bacteria are resistant to antibiotics, Dr Sahota has suggested. "These also may form bio-films in the distribution pipeline," he said. "Standard chlorination of water doesn't kill these microscopic bodies, for it requires more contact time."
The latest-revealed pathogens can cause various diseases, if consumed with contaminated water. Aeromonas hydrophila are ever-present microorganisms documented in a variety of human illnesses, including septicaemia, and wound and lung infection. Most frequent reports indicate the association of the Aeromonas species with acute gastroenteritis. Yersinia enterocolitica causes diarrhoea, arthritis and terminal ilitis.