(KRON) — The Center for Disease Control is monitoring the spread of a bacteria called Shigella that is causing gastrointestinal infections.

Shigella infections are not new and are most common among young children. Last year, about 5-percent of infections were strong enough to resist treatment, the CDC said.

Dr. Peter Chin-Hong from UCSF said the concern is that the resistance will continue to trend upward. “Going from zero in 2015 to 0.4-percent in 2019 and then last year all of a sudden it was 5-percent of cases where no drugs work, that’s kind of frightening to me,” said Dr. Chin-Hong.

The symptoms of Shigella include diarrhea, fever and abdominal cramps. Dr. Chin-Hong said about 40-percent of people who get it are hospitalized but that most get better on their own. The CDC has seen an increase of spread among gay and bisexual men, as well as others.

“If it’s Shigella I think clinicians now know that if the individual is sick enough to be treated that we may need to work with the CDC and bring out some alternative antibiotics. Ones that we don’t commonly use,” said Dr. Chin-Hong.

KRON On is streaming news live now

According to the CDC, Shigella is usually spread when infected fecal matter enters the nose or mouth. “Washing hands has made a comeback now and I think Shigella is one of those places where it can also be helpful,” said Dr. Chin-Hong.