zoonoses and communicable diseases common to ... - PAHO/WHO

PSEUDOTUBERCULOUS YERSINIOSIS 219Russian Far East, a scarlatiniform form of the disease has been described, with severalthousand cases (Stovell, 1980). Three outbreaks occurred in the period1982–1984 in Okayama Prefecture (Japan). In one outbreak, serogroup 5a was isolatedfrom 16 patients and the infection was tied to contaminated foods. The othertwo outbreaks occurred in remote mountainous regions and affected a large numberof preschool- and school-aged children, as well as adults. In these two outbreaks, acommon source of infection could not be found, although it may have been well orstream water. Serotype 2c was detected in the feces of one patient and in well water.In another case, serotype 4b was detected in the feces of the patient and of a wildanimal (Inoue et al., 1988).Also in Japan, outbreaks occurred in 1991 in Aomori Prefecture in four primaryschools and one secondary school. A total of 732 people became ill, including students,teachers, and administrative personnel; 134 were hospitalized. Y. pseudotuberculosisserotype 5a was isolated from 27 (81.8%) of the 33 samples examined.The strains isolated had the plasmid that determines various virulence factors, suchas calcium dependence at 37°C and autoagglutination. The outbreak was attributedto food served in the schools, but no specific food could be pinpointed. The etiologicagent was also isolated from wastewater and the cooks’ feces (Toyokawa et al.,1993). Serotypes 1, 2, and 3 have been isolated in Asia, Europe, Canada, and the US;serotypes 4 and 5 have been isolated in Europe and Japan; and serotype 6 has beenisolated in a few cases in Japan (Quan et al., 1981).Occurrence in Animals: Numerous species of domestic and wild mammals,birds, and reptiles are naturally susceptible to the infection. The disease occurs sporadicallyin domestic animals. In Europe, devastating epizootics have been describedin hares. Epizootic outbreaks have occurred in guinea pigs, wild birds, turkeys,ducks, pigeons, and canaries. Serotype 1 predominates in animal disease.The Disease in Man: The disease mainly affects children, adolescents, and youngadults. In the past, the most recognized clinical form was mesenteric adenitis orpseudoappendicitis with acute abdominal pain in the right iliac fossa, fever, andvomiting. In the outbreaks in Okayama Prefecture, abdominal pains were accompaniedby diarrhea. In another large outbreak in Japan, 86.4% of 478 patients hadpyrexia, 73.8% had rashes, 66.7% had abdominal pain, and 63.4% experienced nauseaand vomiting. Another frequent sign is strawberry tongue and painful pharyngealredness. In the 19 patients studied in Finland (Tertti et al., 1984), the diseaselasted from one week to six months. Twelve of the patients had complications: sixhad erythema nodosum, four had arthritis, one had iritis, and one had nephritis.The incubation period is still unclear, but is estimated to last from one tothree weeks.Septicemia caused by Y. pseudotuberculosis is rare and usually appears in weakenedindividuals, particularly in the elderly or immunodeficient.In the Russian Far East, a scarlatiniform type of the disease has been described.This syndrome is characterized by fever, a scarlatiniform rash, and acute polyarthritis.The disease can be reproduced in volunteers using cultures of the agent isolatedfrom patients (Stovell, 1980).Y. pseudotuberculosis is sensitive to tetracycline. Ofloxacin proved very effectivein treatment tested on infected rats, but the beta-lactams were not effective(Lemaitre et al., 1991).