Something is making the kids in Montgomery, Alabama sick and health officials aren’t sure just why yet.

As CNN reports, 86 children this week have been given medical care due to similar complaints of gastrointestinal distress, including vomiting, diarrhea, and cramps, leading the Department of Public Health to suspect a possible food-borne outbreak. Though 30 children were hospitalized, only one currently remains under the close watch of doctors.

Its source is likely two branches of the Sunny Child Care Center, with food provided by the same kitchen housed in the South Court Street location. A concerned parent notified the Health Department about their suspicions of an outbreak on Tuesday, June 23. Dr. Mary G. McIntyre of the Public Health Department, in a news release today, noted that over 300 children were in attendance that day.

Tests ran for common causes of food poisoning, like E. coli and Salmonella, have so far turned up negative, but officials have detected traces of toxin created by the bacteria Staphylococcus Aureus in several of the food products served by the kitchen. The investigation, involving detailed collection of environmental and clinical samples and interviews with the daycare staff, continues. "Public health environmentalists are working with the facility regarding the kitchen and food handling to avoid any reoccurrence and prevent future food-related outbreaks," McIntyre wrote.

In the meantime, officials are warning parents who have sick children who attended Sunny Child Care to not visit any other daycare centers until their child is free of symptoms for at least 24 hours.

Earlier this May, the Centers for Disease Control (CDC) released a preliminary report on the recent prevalence of food-borne disease, noting that these outbreaks remain difficult to prevent. "Progress has been made in decreasing contamination of some foods and reducing illness caused by some pathogens," they wrote. "However, little or no recent reductions for most infections have occurred."

They concluded that tighter regulation of products entering the food supply and changes in how we process our food may help combat these infections from reaching the public. "In 2015, FDA plans to publish regulations for safer produce, processed foods, and imported foods, as mandated by the Food Safety Modernization Act," they wrote. "Vaccination of breeder poultry flocks, in combination with biosecurity measures, has been shown to reduce contamination of poultry meat."