Treatment-resistant typhus, which is mostly native to South Asia, has jumped nearly 200 times across borders in the past three decades, according to new research that underscores the growing global threat of antibiotic-evading infections.
Between 2014 and 2019, scientists followed up on the genomes of 3,489 cases of S. typhi, the bacteria that cause typhoid fever and kill more than 100,000 people annually. Data from four high-load nations – Bangladesh, India, Nepal and Pakistan – were combined with an analysis of 4,169 similar samples from more than 70 countries over a period of 113 years, making it the largest study of its kind.
The findings, published in The Lancet Microbe, showed that while resistance to first-line treatments generally declined in South Asia, global issues remained. The number of strains that could overwhelm macrolides and quinolones, two major types of antibiotics, climbed sharply and spread frequently to other countries, the study found.
Scientists have been drumming up for years about increasing cases of deadly insects that can survive treatment with the most powerful antibiotics. Drug-resistant diseases killed more people than HIV or malaria in 2019, according to a separate study published in January. Recent examples include increasing infections in the US, along with last year’s fatal fungal outbreak in India, where the abuse of antibiotics in humans and animals is exacerbated by poor sanitation.
The findings are “a real cause for concern,” said Jason Andrews, an associate professor at Stanford University and the study’s lead author, who called for preventative measures, especially in high-risk countries.
“The fact that resistant strains of S. typhi have spread so many times internationally also underscores the need to consider typhoid control, and antibiotic resistance more generally, as a global rather than a local problem,” he said.
The study, funded by the Bill & Melinda Gates Foundation, had certain limitations, including the under-representation of samples from endemic regions such as sub-Saharan Africa and Oceania. The S. thyphi genome covered only a fraction of all typhoid cases, meaning that the researchers’ estimates probably interrupted the true scale of global distribution and resistance.
(This story was not edited by techlives staff and is automatically generated from a syndicated stream.)