Bean sprouts thought to be behind a spike in Salmonella cases in SA have been traced back to Queensland, health authorities say.

Raw mung bean sprouts linked to more than 230 Salmonella cases in South Australia originated in Queensland but health authorities don't know where they were contaminated.

Almost half of the Salmonella Saintpaul cases have developed during the past 12 days and 43 people have been admitted to hospital since the outbreak began in December, SA Health says.

Chief Medical Officer Paddy Phillips, who usually sees fewer than 20 cases of the strain each year, has urged people not to eat raw bean sprouts and food outlets not to serve them raw.

The seeds came from Queensland before being sprouted and packaged in South Australia but SA Health hasn't confirmed where they were contaminated.

"Because we've got the positive [result] from one of the factories, we're working through other factories and we're working right back through the processing chain doing a forensic examination with PIRSA (Primary Industries and Regions SA)," Prof Phillips told ABC radio on Friday.

"The reason why we're not asking people to recall them ... is because you can make them safe.

"Ditch them or blanch them for 10 seconds in boiling water and you should be OK."