Parental vaccine refusal in Wisconsin: a case-control study.

INTRODUCTION: Successful immunization programs have diminished parental fear of diseases and increased fear of vaccines. Children with nonmedical exemptions to school immunization requirements are at increased risk of acquiring and transmitting disease. We explored differences in vaccine attitudes, beliefs, and information sources among parents of exempt and vaccinated children. METHODS: Self-administered surveys were mailed to 780 parents of children with nonmedical exemptions (cases) and 1491 parents of fully-vaccinated children (controls). RESULTS: Vaccines most often refused by exempt children were varicella (49%) and hepatitis B (30%). The most common reason for claiming exemptions was vaccine might cause harm (57%). Parents of vaccinated children were less likely than parents of exempt children to report concern about vaccine safety, question the need for immunization, and oppose immunization requirements. Nearly 25% of parents of vaccinated children reported that children get more immunizations than are good for them and 34% expressed concern that children's immune systems could be weakened by too many immunizations. Both groups received information from health care professionals; parents of exempt children were more likely to also consult other sources. CONCLUSIONS: Our findings support the need for improved methods to communicate vaccine safety information. Further studies to explore vaccine safety concerns among parents are needed.

A countywide outbreak of pertussis: initial transmission in a high school weight room with subsequent substantial impact on adolescents and adults.

OBJECTIVE: To describe a large communitywide pertussis outbreak where aggressive diagnostic and treatment measures were used to control the outbreak. DESIGN: Retrospective analysis, May 2003 through February 2004. SETTING: Fond du Lac County, Wisconsin (population 98,882). PARTICIPANTS: Health department personnel conducted case and contact investigations of suspected outbreak-associated illnesses using standard pertussis reporting forms and clinical evaluation and management protocols. Persons with compatible illness were tested for Bordetella pertussis using culture and for B pertussis DNA using polymerase chain reaction. Cases were classified using Council of State and Territorial Epidemiologists definitions. INTERVENTIONS: Health alerts and aggressive testing and treatment of suspected cases of pertussis illness and contact prophylaxis in the community. MAIN OUTCOME MEASURES: Incidences by age, onsets over time, and vaccine coverage in case patients. RESULTS: We identified 261 pertussis cases among county residents; 149 (57%) were laboratory confirmed. Of the first 57 case patients, 47% reported using a particular high school weight room. Pertussis incidence was high in all age groups; 86% of case patients were 10 years or older. Among 156 case patients with reported vaccination histories, 84% had received 5 or more doses of pertussis-containing vaccine. Adults reported significantly more severe pertussis symptoms than adolescents. CONCLUSIONS: Pertussis transmission among adolescents using a school weight room instigated a countywide outbreak with substantial incidence and morbidity among adolescents and adults. Aggressive testing and treatment in the outbreak response likely contributed to a sharp reduction in cases. This labor- and resource-intensive outbreak highlights potential benefits of pertussis booster vaccination among adolescent and adult populations.

Evaluation of polymerase chain reaction and culture for diagnosis of pertussis in the control of a county-wide outbreak focused among adolescents and adults.

During a large pertussis outbreak, culture and polymerase chain reaction (PCR) were used to identify 149 case patients; of these case patients, 79 had positive PCR and culture results, 59 had positive PCR results and negative culture results, 11 had negative PCR results and positive culture results (10 PCR-negative, culture-positive specimens were collected < or = 14 days after illness onset). PCR and culture of samples obtained < or = 2 weeks after illness onset and PCR of samples obtained > 2 weeks after illness onset proved to be most diagnostically useful.