Public Health England published study results in The Lancet on Tuesday that showed tuberculosis most commonly spreads between people with a history of drug use and within ethnic communities.
PHE said that cases of multi-drug resistant tuberculosis have increased from 28 cases per years to 81 cases per year during the past 12 years. Approximately 681 cases of MDR-TB were confirmed between 2000 and 2012.
Researchers looked at the genetic code of MDR-TB from every patient diagnosed with TB between 2004 and 2007 to discover which cases were related through person-to-person infection. The team discovered that 12 separate cluster groups were present.
"Transmission of MDR-TB in the UK is extremely low but our study found that where it does occur it is mainly in the household and is associated with being UK-born and drug use or within specific communities," Laura Anderson, a senior TB scientist at PHE, said. "It tends to spread within communities who share ethnicity or social risk factors, like drug use, rather than spreading outside their specific ethnic or social groups."
MDR-TB occurs when the tuberculosis bacteria does not respond to a drug combination of two to four antibiotics. The drug-resistant strain can be transmitted from another person or develop as a result of incomplete treatment.
"The increase in drug resistant cases which we are observing year on year in the UK remains a big concern and a priority for PHE," Ibrahim Abubaker, the head of TB at PHE, said. "MDR-TB continues to disproportionately affect those in hard-to-reach and vulnerable groups. In order to reduce TB cases in the future, it's very important that health commissioners, especially in parts of the country with the highest rates of TB, prioritize the delivery of appropriate clinical and public health TB services."