Streptococcal contamination of food: an unusual cause of epidemic pharyngitis

The purpose of this article is to define the distinguishing characteristics of food-borne streptococcal pharyngitis by reviewing the literature. The m ain cause of this infection lies in poor handling and preservation of cold salads, usually those which contain eggs and are prepared some hours before serving. A shorter incubation period and a higher attack rate (51-90%) tha n in transmission by droplets was noted. The epidemics tend to occur in war m climates and in the hottest months of the year. Streptococcus pyogenes se ems to originate from the pharynx or hand lesions of a food handler. In com parison to airborne transmission symptoms such as sore throat, pharyngeal e rythema, and enlarged tonsils, submandibular lymphadenopathy are more frequ ent than coughing and coryza. Seven out of 17 reports revealed an M-untypea ble serotype, which may possess virulent characteristics. Penicillin prophy laxis was shown to limit additional spread of the infection. There were no nonsuppurative sequels, and suppurative sequels were very rare. We assume t hat the guidelines for the prevention of food poisoning would apply to food -borne streptococcal pharyngitis. Food handlers should be supervised to ens ure they comply with strict rules of preparation and storage of food. Cold salads, especially those containing eggs, should not be left overnight befo re serving.