A retrospective epidemiologic analysis of human salmonellosis in Hawaii suggests that the reported incidence is seven to eight times higher than in the rest of the United States, and discusses the reasons for this difference. Hogs and hog products are a chief reservoir and vehicle of transmission to humans.
Epidemiologic Aspects of Salmonellosis in HawaiiIntroduction Salmonellosis is a widespread public health problem in the United States. The major vehicles of infection for humans are foods of animal origin, particularly frozen or dried egg products, dried milk, poultry, and packaged boneless meats. 1-14 However, salmonellae are transmitted widely or cause outbreaks through such diverse products as seafoods,' bakery goods, 11.15,16 coconut, 17,18 food supplements 19.20 cotton seed protein,20 dried yeast 20,21 cereal powder22 smoked fish,23 unpasteurized whole milk,24 water25 and carmine dye.26 Control is difficult due to the diversity and complexity of chains offood production and distribution.Since 1950 Hawaii has had a reported incidence of human salmonellosis seven to eight times higher than the national incidence, as reported by the National Communicable Disease Center. This report reviews laboratory documented salmonellosis in Hawaii since 1950 with the intent of explaining this high reported incidence and presents data which suggest that incidence based on reported cases is an inadequate parameter for comparing levels of salmonellosis among states. Sources of human infection are described based on the distribution of salmonellae sterotypes from animal and human sources, contamination of foods of animal origin, distribution of human salmonellosis by season, and incidence by race.
Methods Laboratory ProceduresIsolation and serotyping of salmonellae were performed at the Laboratory Branch of the Hawaii Deprtment of Health. All specimens were streaked on SalmonellaShigella (SS) agar and enriched in selenite F and tetrationatebrilliant green broths. After incubation at 37°C for 24 hours. Colonies resembling salmonellae on SS agar were subcultured into tubes ofTriple Sugar Iron ([SI) agar. After incubation at 370 for 24 hours, TSI cultures exhibiting reactions characteristic of salmonellae were tested for urease activity.All urease negative cultures were tested for mobility, indole production, and fermentation of dextrose, sucrose, mannitol, and salicin. Cultures showing reactions characteristic of salmonellae were typed serologically by somatic 0 and flagella H antisera to determine the group and specific serotype.
