Typhoid fever might seem like a thing of the past in richer countries, but it’s still a big threat in many parts of the world. This ancient illness, which has existed for thousands of years, is making a comeback—stronger than before.
In 2022, scientists found that the bacteria causing typhoid are changing. These new types are becoming resistant to medicine, and they’re spreading fast. They’re taking over from the older, less dangerous types.
At the moment, antibiotics are the only way to treat typhoid, which is caused by a bacteria called Salmonella enterica serovar Typhi (or S Typhi). But in the last 30 years, S Typhi has been getting stronger and harder to kill with standard medicine, according to a study published in The Lancet Microbe.
Researchers looked at 3,489 typhoid samples collected from 2014 to 2019 in Nepal, Bangladesh, Pakistan, and India. They found a rise in a very strong type of typhoid called extensively drug-resistant (XDR) Typhi.
XDR Typhi doesn’t just ignore older antibiotics like ampicillin, chloramphenicol, and trimethoprim/sulfamethoxazole. It’s also becoming resistant to newer drugs, such as fluoroquinolones and third-generation cephalosporins.
Ancient Killer Is Rapidly Becoming Resistant to Antibiotics, Study Warns
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Even worse, these tough new strains are spreading quickly to other countries.
While most XDR Typhi cases started in South Asia, nearly 200 cases have spread to other parts of the world since 1990. These superbugs have shown up in Southeast Asia, East and Southern Africa, and even places like the UK, USA, and Canada.
“The speed at which these dangerous strains of S Typhi have appeared and spread is worrying,” said Dr. Jason Andrews from Stanford University. “We urgently need to improve prevention in countries most at risk.”
Experts have warned about drug-resistant typhoid for a long time. The first case of XDR typhoid was found in Pakistan in 2016. By 2019, it had become the most common type there.
In the past, doctors used strong antibiotics like quinolones, cephalosporins, and macrolides to fight it. But by the early 2000s, most cases in South Asia had already stopped responding to quinolones. Resistance to cephalosporins was rising too.
Now, there’s only one pill left that works—azithromycin. But even that might not last much longer.
The 2022 study found that typhoid bacteria are starting to resist azithromycin too. If the XDR Typhi strain picks up this resistance, doctors will have no oral drugs left to treat typhoid.
If it goes untreated, typhoid can kill up to 20% of people who get it. Right now, about 11 million people get typhoid every year, as per Science Alert.
Saccarine, surprisingly, can overcome antibiotic resistance
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Normally it takes billions of dollars and decades to develop a new antibiotic. But here we have a compound that's already widely used, and it not only kills drug-resistant bacteria but also makes existing antibiotics… pic.twitter.com/3vl29O2tGb
We can help prevent future outbreaks with typhoid vaccines. But unless we make these vaccines available to more people around the world, we might face another serious health crisis.
“The rise of XDR and azithromycin-resistant S Typhi makes it even more urgent to use vaccines, especially in countries where drug resistance is already a big problem,” the researchers said.
They also warned that because typhoid spreads across borders, we need to act everywhere—not just in the most affected countries.
South Asia still has the most typhoid cases—about 70% of all cases—but as COVID-19 showed us, diseases can spread quickly in today’s world.
To stop that from happening, health experts say we need to improve access to typhoid vaccines and keep working on new antibiotics. One study in India showed that vaccinating kids in cities could cut typhoid cases and deaths by 36%, the study in The Lancet Microbe claimed.
Pakistan has already taken the lead—it was the first country to include the typhoid vaccine in routine shots for children. Experts say more countries need to do the same.
Drug resistance is now one of the biggest causes of death worldwide—killing more people than HIV or malaria. Vaccines, where available, are some of the best tools we have to stop this.
We’re running out of time.