ABSTRACT
CONTEXT: Hepatitis A is a common vaccine-preventable disease in the United States. Most cases occur during community-wide outbreaks, which can be difficult to control. Many case-patients have no identified source. OBJECTIVE: To identify foodborne and household sources of hepatitis A during a community-wide outbreak. DESIGN: Serologic and descriptive survey. SETTING: Salt Lake County, Utah. PARTICIPANTS: A total of 355 household contacts of 170 persons reported with hepatitis A during May 1996 to December 1996, who had no identified source of infection; and 730 food handlers working in establishments where case-patients had eaten. MAIN OUTCOME MEASURE: Prevalence of immunoglobulin M antibodies to hepatitis A virus (IgM anti-HAV) among household and food service contacts. RESULTS: Overall, 70 household contacts (20%) were IgM anti-HAV-positive, including 52% of children 3 to 5 years old and 30% of children <3 years old. In multivariate analysis, the presence of a child <3 years old (odds ratio [OR]: 8.8; 95% confidence limit [CL]: 2.1,36) and a delay of >/=14 days between illness onset and reporting (OR: 7. 9; 95% CL: 1.7,38) were associated with household transmission. Of 18 clusters of infections linked by transmission between households, 13 (72%) involved unrecognized infection among children <6 years old. No food handlers were IgM anti-HAV-positive. CONCLUSION: During a community-wide outbreak, HAV infection among children was common, was frequently unrecognized, and may have been an important source of transmission within and between households. Transmission from commercial food establishments was uncommon. Ongoing vaccination of children may prevent future outbreaks.
Subject(s)
Disease Outbreaks , Disease Transmission, Infectious , Hepatitis A/transmission , Acute Disease , Adolescent , Adult , Child , Child, Preschool , Contact Tracing , Family Health , Female , Food Handling , Hepatitis A/epidemiology , Hepatitis A/ethnology , Hepatitis A Antibodies , Hepatitis A Virus, Human/immunology , Hepatitis Antibodies/blood , Humans , Infectious Disease Transmission, Vertical , Male , Middle Aged , Risk Factors , Seroepidemiologic Studies , Utah/epidemiologyABSTRACT
Between January 1984 and December 1989, 102 indigenous cases of Lyme disease were reported in North Carolina. Lyme disease was reported in each of the three major geographic regions of the state: mountain, piedmont, and coastal plain. One or more diagnoses were made in 42 of 100 counties. Patients ranged in age from 5 months to 78 years (median, 27 years); 58 patients (57%) reported a history of tick exposure within 1 month of the onset of symptoms. Erythema migrans was reported by 93 patients (91%). Arthritis (30%), neurologic symptoms (10%), and cardiac abnormalities (7%) were observed. Thirty of the 102 cases were confirmed serologically by indirect fluorescence microscopy or enzyme-linked immunosorbent assay.
