Drug-resistant Salmonella outbreak linked to US beef, cheese in Mexico

An outbreak of drug-resistant Salmonella that impacted more than 250 people in the United States from mid-June 2018 to March 2019 has been linked to beef from the United States and soft cheese from Mexico, according to the Centers for Disease Control and Prevention. Cases involving the drug-resistant Salmonella were identified in 32 states, with nearly half of the patients having reported trips to Mexico prior to the illness.Salmonella is a bacteria that is most commonly contracted from contaminated water and food. When consumed, this bacteria causes a number of symptoms, including fever, stomach pain, and diarrhea. Though most people are able to make a full recovery within a week and only need to drink fluids, some individuals are severely impacted and may need antibiotics

In those cases, doctors prescribe an antibiotic called azithromycin, commonly offered under the brand name Zithromax in the form of a 'Z-Pak' or 'Tri-Pak.' There's a variety of Salmonella that is multi-drug-resistant, however, including to the effects of azithromycin, which makes it harder to treat.

Until 2017, according to the CDC, Salmonella resistant to this antibiotic accounted for less than 0.5-percent of cases in the United States. That changed primarily with the Salmonella enterica serotype Newport (Newport) outbreak that took place from June 2018 to March 2019. During that time, 255 people were identified as infected with this drug-resistant bacteria.

As part of the investigation, officials found Oaxaca and queso fresco soft cheese that was sold in Tijuana, Mexico, was contaminated with the drug-resistant Salmonella strain identified in at least one patient who became ill in the US following their trip to Mexico. As well, this same strain was found in beef samples from two Texas facilities.