'Superbug' Affects World Travelers: Drug Resistant Shigellosis Outbreak In US, Says CDC

World travelers returning to the United States seem to be coming back with a drug-resistant intestinal stomach bug.

Officials at the Centers for Disease Control and Prevention (CDC) note that the bug, shigellosis, has made 243 people sick at this time in 32 states and Puerto Rico between May 2014 and February 2015. Clusters of the illness have also been reported in Massachusetts, California and Pennsylvania according to the CDC.

So far, the Shigella sonnei bacteria has been resistant to the antibiotic treatment ciprofloxacin, the drug that's most often used to treat bacteria infections that attack the digestive tract. However, most Shigella strains in the United States have already grown resistant to the antibiotics ampicillin and trimethoprim/sulfamethoxazole.

This is particularly troublingly considering the growing problem with antibiotic resistance in the United States.

However, at this time, some health officials caution against using the word "superbug" to describe the the resistance of the drug.

"It would be better to say resistant to the first-time treatment choice," said Dr. Anna Bowen, a CDC medical epidemiologist and lead author.

"I'm no longer surprised when I see these," added Dr. Pritish Tosh, an infectious disease physician and vaccine researcher at the Mayo Clinic in Rochester, Minnesota. "The finding that several bacteria are resistant to what would commonly have been used is indicative of the growing trend of antibiotic resistance."

However, health officials note that it's still best to stay clean and safe when traveling and every day, in general. In other words, always wash your hands.

"These outbreaks show a troubling trend in Shigellainfections in the United States," said CDC Director Dr. Tom Frieden in a news release. "Drug-resistant infections are harder to treat and because Shigellaspreads so easily between people, the potential for more - and larger - outbreaks is a real concern."