Bovine tuberculosis could be being spread by human-to-human contact, new research has revealed.
Tests surrounding six cases of bovine TB in central England two years ago found that they all originated from one person's exposure, "strongly suggesting" it can be spread by humans.
But the research, published today in the Lancet health journal, says that although there has been a "resurgence" in the number of cases of bovine TB in the UK, a comparative rise among humans has not been seen.
The disease usually occurs in older people who have been infected by drinking unpasteurised milk in the past, today's report continues, with person-to-person transmission described as "very rare".
However, genetic fingerprinting by the Health Protection Agency (HPA) between 2001 and 2005 found that of 20 cases of Mycobacterium bovis infection among humans, six were genetically indistinguishable.
None of the patients, one of which died from M bovis meningitis, had been exposed to the bovine disease apart from the source case.
But all of the individuals had visited the local bar and city centre nightclub, suggesting person-to-person transmission had taken place.
"This report of several instances of M bovis transmission between people in a modern urban setting emphasises the need to maintain control measures for human and bovine tuberculosis," writes study co-author Grace Smith.
"Transmission and subsequent disease was probably due to a combination of host and environmental factors. Prospective surveillance and DNA fingerprinting identified the cluster, enabling health protection teams to set up control measures and prevent further transmission."
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