The number of cases in a Buncombe County salmonella outbreak surged 30 percent over the weekend, county health officials said Monday.Government food and health regulators are zeroing in on a tempeh ingredient sold by a Maryland company as the possible source of the local bacterial infection.The Food and Drug Administration is now among the agencies involved in the investigation of ingredients in the cultured bean product.Meanwhile, officials with Smiling Hara Tempeh said the small Candler company is looking at restarting production after first doing a thorough review of its system.Fourteen more people reported being ill over the weekend, raising the total from 46 on Friday to 60.The disease causes diarrhea that may be bloody, high fever, headache and abdominal pain. The salmonella behind the outbreak is the rare paratyphi B type that causes paratyphoid fever, not to be confused with typhoid fever, said county Health Director Gibbie Harris. It is rarely fatal but can require hospitalization and is dangerous to the young, elderly and those with weak immune systems.It appears that some of the people newly sickened were exposed to the bacteria together, possibly at parties, Harris said.“We don’t know at this point because we are starting to do the interviews, but it is a possibility that it is a combination of food and person-to-person exposure,” she said.Harris said people should not be alarmed at the spike in cases, since small surges are typical in outbreaks.“It is going to take a bit of time before this tapers off,” she said.Public education is key to stopping the outbreak, including an emphasis on good sanitation such as hand washing and appropriate food-handling techniques.The bacteria are spread from fecal matter and can be transferred by such things as unwashed or undercooked food, diapers or even light switches.County communicable disease nurses and state agriculture workers traced the outbreak, which started in March, to the cultured bean product made locally.