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Infection Spreading Outside Hospitals

Health care-associated infections (HAIs) have become more common as medical care has grown more complex and patients have become more complicated. HAIs are mostly linked with significant morbidity, mortality, and cost. Named from the Greek kloster, for spindle, a class of bacteria known as Clostridia is very common in nature.

They look like slender rods with a bulge at one end, like a tadpole or maple seed when seen under microscope. They thrive in soil, marine sediments and humans and tend to live on our skin and in our intestines. They are really dangerous and can kill humans as well. But most of the strains are harmless, but tetanus, botulism and gangrene are caused by clostridial species. Although vaccination, sanitation and improved medical care have made these infections less common but they exist still. Clostridia can cause diarrhoea and a life-threatening infection of the intestines. Due to this bug, around 30,000 death cases were reported in 2011. Initially this problem was mainly confined to hospitals and nursing homes. It was discovered in 1935 by scientists in Denver in the intestinal flora of healthy infants. The bacterium was harmless to the infants but proved lethal when injected into rabbits, providing an early clue to its danger. Simultaneously, some scientists in the United Kingdom were pioneering the use of penicillin to treat bacterial infections. Though the drug was effective but some patients developed severe diarrhoea as a side effect. As antibiotics became widely available in the 1950s, this adverse effect became more common. Earlier the researchers found that this happened due to Staphylococcus aureus, a common pathogen and the usual treatment for staph is the antibiotic vancomycin, and many patients showed improvement but the real cause was Clostridia. In 1974, scientists in Cincinnati discovered a toxin in affected patients' stool, and traced it to C. diff. Clostridial species can revert to hardy spores that resist disinfectants due to which we see so many infections occurring in hospitals and nursing homes. Health care workers were unknowingly spreading the spores and inoculating patients. It was found that in healthy intestines, the sheer diversity of bacteria meant that C. diff couldn't establish a foothold for out-of-control growth. Australian scientists discovered, in 1991, that C. diff was responsible for 5.5 per cent of outpatient diarrheal infections, and researchers in Boston published additional evidence of community-acquired C. diff in 1994. Diet strongly influences the microbiome. A recent study found that trehalose, a common food additive, definitely enhances the virulence of C. diff, although Guh cautions that there have been difficulties replicating the findings. However, the rising rates of C. diff infection in the community are a major public health concern and who knows when they become a sign of an even larger problem.


By: Anuja Arora