Boston: The bacteria that cause typhoid fever are becoming increasingly resistant to some of the most important antibiotics. A study published in the journal ‘The Lancet Microbe’ gave this information. The largest genome analysis of Salmonella enterica serovar Typhi (S. Typhi) also shows that resistant strains – almost all of which originated in South Asia – have spread to other countries nearly 200-fold since 1990. Researchers found that typhoid fever is a global public health concern, infecting 11 million people every year and killing more than 100,000.
The impact of typhoid is highest in South Asia – which accounts for 70 percent of the global disease burden – and also has significant impacts in sub-Saharan Africa, Southeast Asia, and Oceania, highlighting the need for global action, the researchers report. . Antibiotics can be used to successfully treat typhoid fever infection, but resistant S. The emergence of Typhi strains affects their effectiveness. Resistant S. Analysis of the rise and spread of Typhi has so far been limited, with most studies based on small samples.
Recently many strains of typhoid have been found
Study lead author Jason Andrews, from Stanford University in the US, said the rapid emergence and spread of highly resistant strains of S. Typhi in recent years is a cause for real concern and underscores the urgent need to expand containment programs, especially in high-risk countries. Andrews pointed out that along with this, S. As resistant strains of Typhi have spread internationally, this underscores the need to look at typhoid control and antibiotic resistance as a global rather than a local problem at times.
Samples were taken from Bangladesh, India, Nepal and Pakistan
In the new study, researchers obtained 3,489 S. Typhi isolates and performed whole-genome sequencing. In addition, 4,169 S.O.s were isolated from more than 70 countries between 1905 and 2018. the Typhi specimens were also sequenced and included in the analysis. The genes conferring resistance were identified in 7,658 sequenced genomes using a genetic database.
Bacteria strengthened against antibiotics
The strains that contained genes conferring resistance to the previously used antibiotics ampicillin, chloramphenicol, and trimethoprim/sulfamethoxazole were classified as multidrug-resistant (MDR). The authors also detected the presence of genes conferring resistance to macrolides and quinolones, which are among the most important antibiotics for human health. The analysis shows that resistant S. Typhi strains have spread between countries at least 197 times since 1990.
Typhoid cases increased in Pakistan due to a decline in India
The researchers said that these strains were most often found in South Asia and South Asia to Southeast Asia, East, and South Africa. They have also been reported in Britain, America, and Canada. Since the year 2000, in Bangladesh and India, MDR S. Typhi has declined and remains low in Nepal but has shown a slight increase in Pakistan.
