An outbreak of typhoid fever in Hyderabad and its adjoining areas in Sindh has been linked to an extensively drug resistant ‘superbug’ strain, says a study published this week.
The study, based on research by a team of scientists from Britain’s Wellcome Sanger Institute and Aga Khan University, has analyzed the genetics of the typhoid strain, finding that it has mutated and acquired an extra piece of DNA to become resistant to multiple antibiotics.
The outbreak of the drug-resistant typhoid fever was first reported in Hyderabad in November 2016. Experts from Aga Khan University have been quoted in the media as saying that the strain, known as H58, is still spreading in the region.
The researchers have found that the bacterial strain is now resistant to at least five antibiotics. These include three first-line drugs (chloramphenicol, ampicillin, and trimethoprim-sulfamethoxazole) as well as fluoroquinolones and third-generation cephalosporins.
Though there is no official data available on number of casualties, but media reports quoting health authorities have claimed that there were at least 800 cases of drug-resistant typhoid in Hyderabad between 2016 and 2017.
“This is the first time we have seen an outbreak of extensively drug-resistant typhoid,” Elizabeth Klemm, who co-led the analysis work at the Sanger Institute, said in a statement. “This outbreak was caused by a multidrug-resistant strain that had gone a step further and acquired an extra piece of DNA encoding additional genes for antibiotic resistance.”
Typhoid is a highly contagious infection caused by the Salmonella enterica serovar Typhi bacteria. It is contracted by consuming contaminated foods or drinks and symptoms include nausea, fever, abdominal pain, and pink spots on the chest. It can be fatal if not treated in time.
According to the Sanger Institute, the H58 strain of typhoid was first detected in South Asia about 25 to 30 years ago. It initially took hold in Asia and Africa before spreading around the world, becoming the dominant strain by 2015.