International travelers are bringing a multidrug-resistant intestinal illness to the United States and spreading it to others who have not traveled, according to a report released by the Centers for Disease Control and Prevention (CDC). Shigella sonnei bacteria resistant to the antibiotic ciprofloxacin sickened people in 32 states and Puerto Rico between May 2014 and February 2015. Research by the CDC found that the drug-resistant illness was being repeatedly introduced as ill travelers returned and was then infecting other people in a series of outbreaks around the country.
The Shigella bacteria infect your intestines and trigger crampy rectal pain, bloody or mucus-laced diarrhea and vomiting. Shigella is a species of enteric bacteria that causes disease in humans and other primates. The disease caused by the ingestion of Shigella bacteria is referred to as shigellosis. Shigella infection is the third most common cause of bacterial gastroenteritis in the United States, after Salmonella infection and Campylobacter infection and ahead of E. coli infection.
Multidrug-resistant Shigella has caused several outbreaks over the past year in the U.S., the CDC reported in the journal Morbidity and Mortality Weekly Report. At least 243 people have gotten sick and about 20 percent were hospitalized. Those numbers may not sound like much — especially when you consider a half million Americans get regular Shelligosis each year. But this strain of Shigella is resistant to the go-to drug for the bacteria: ciprofloxacin.
“If rates of resistance become this high, in more places, we’ll have very few options left for treating Shigella with antibiotics by mouth,” says epidemiologist Anna Bowen, who led the study. Then doctors will have to resort to IV antibiotics. Shigella is incredibly contagious. It spreads through contaminated food and water. “As few as 10 germs can cause an infection,” Bowen says. “That’s much less than some other diarrhea-causing germs.”
From May to February, the Cipro-resistant strain popped up in 32 states, with large clusters in California, Massachusetts and Pennsylvania. Bowen and her team linked several of these outbreaks to international travel, including trips to India, the Dominican Republic and Morocco. But in many instances, people who got sick hadn’t traveled outside the U.S. So the strain has already started to circulate in some states, she says.
“This outbreak really highlights that multidrug-resistance in other countries is also a problem for the U.S.,” Bowen says. “Cases [in the U.S.] have continued to accrue over the month since we put together this report. So we’re monitoring it carefully,” she adds.
The National Institute of Allergy and Infectious Diseases explains the rise of drug resistance and what researchers are doing to fight it.
Most of the time, Shigellosis will go away on its own after about seven days. In rare cases, it causes severe blood infections and death. The CDC reports that about 100 million people get infected with Shigella each year, and about 600,000 die from it. Cipro-resistant Shigellosis is a growing problem globally, especially in Asia.
According to Bowen, the best way to prevent Shigella is practicing good hygiene — wash your hands regularly while traveling and choose foods wisely. “Taking over-the-counter drugs, like Kaopectate and Pepto-Bismol can prevent traveler’s diarrhea,” she says. And if you do get sick, don’t reach for the Cipro first. Instead, Bowen says, go for an over-the-counter anti-diarrheal drug before trying an antibiotic.