Whitney A. Mauer

Detection of Mycobacterium avium subspecies paratuberculosis in naturally exposed dairy heifers and associated risk factors

An observational prospective study was conducted to identify risk factors associated with fecal shedding of Mycobacterium avium ssp. paratuberculosis (MAP) in naturally exposed dairy heifers. The study population consisted of heifers from 8 dairy herds in Michigan participating in a MAP control demonstration project. Ten heifers from 4 age groups (0 to 3, 4 to 6, 7 to 14, and 15 to 24 mo) were selected from each herd every 4 mo for 28 mo and tested for the presence of MAP by fecal culture (FC). Heifers from dams testing positive for MAP by serum ELISA or FC were preferentially selected, with the remainder of the age cohort filled with randomly selected heifers. Logistic regression using generalized estimating equations to account for clustering of data within herds and repeated measures across heifers was used to evaluate the relationship between MAP FC status of heifers and herd risk factors. In total, 1,842 fecal samples were collected from 1,202 heifers. Thirty-six (2%) fecal samples, representing 27 individual heifers, cultured positive for MAP. Heifers shedding MAP were more likely to occur in herds with adult-cow MAP ELISA prevalence >10% (odds ratio = 4.7; 95% confidence interval: 2.0-11.1) and herds milking >300 cows (odds ratio = 5.7; 95% confidence interval: 2.4-13.4). Mycobacterium avium ssp. paratuberculosis can be cultured from the feces of naturally infected dairy heifers. The future performance of these MAP FC-positive heifers is unknown and needs to be explored.

Assessment of avian influenza surveillance and reporting needs of stakeholders in Michigan, 2007

OBJECTIVE To identify stakeholders who should be included in a Michigan-based avian influenza surveillance system (AISS) and to describe their avian influenza (AI) surveillance and reporting needs. DESIGN Cross-sectional survey involving a convenience sample of respondents. SAMPLE 272 federal, state, and local governmental and regulatory agency professionals; veterinarians and laboratory professionals in academia; private practice veterinarians; and poultry industry members. PROCEDURES A needs assessment survey that focused on stakeholder identification, current surveillance methods, information sharing, and desired AISS enhancements was administered by mail, and responses were summarized. RESULTS Various AISS stakeholders were identified, among whom the requirements for surveillance information and methods of reporting (including via a World Wide Web-based database, e-mail, and a website) differed. Although 90% of all respondent types indicated that poultry industry representatives were key stakeholders, < 33% of poultry industry respondents indicated that private practice veterinarians and personnel in laboratories or public agencies should be considered stakeholders. The predominant concern (55.4% of respondents) regarding the current AISS was the effectiveness of communication among agencies, industry, and the public. The primary challenge identified by respondents was confidentiality (30.2% of respondents). CONCLUSIONS AND CLINICAL RELEVANCE In Michigan-and potentially in other regions of the United States-integration of Internet-related data systems and stakeholder communication is likely to promote earlier identification of AI, achieve more effective responses to outbreaks, reduce morbidity among humans and other animals, and decrease outbreak-associated financial losses. Stakeholder education and technological safeguard assurances will be essential in AISS enhancement.