Prospective study of avian influenza infection in backyard poultry flocks and flock handlers in Wisconsin.

BACKGROUND: The continuing epizootic of H5N1 avian influenza (AI) in Asia and subsequent zoonotic transmission has led to heightened concerns about a pandemic and the demand for improved surveillance of poultry in all sectors, including backyard poultry. We conducted a 15-month prospective study to determine the prevalence of AI in backyard poultry and extent of transmission to flock handlers. METHODS: Starting July 2007, registered poultry owners in six counties in central Wisconsin were mailed invitations to participate; household members with poultry exposure were also invited. Premises with < 1000 birds were eligible. Participants completed a baseline interview to characterize poultry exposures. Illness in flocks and flock handlers was monitored using semimonthly telephone interviews and self-report of acute influenza-like symptoms by flock handlers. Participants provided blood at baseline and at the end of the surveillance period for serology and, if ill, nasopharyngeal, eye, and throat swabs for viral testing. Blood was also collected at baseline from a convenience sample of adult poultry. RESULTS: We enrolled 87 flocks and 128 persons who had regular contact with poultry. Influenza-like symptoms were reported by 77 (65%) persons. Swabs were collected from 53 persons at 88 illness episodes. AI was not isolated, but five persons were positive for human influenza. Twenty-one participants (20%) seroconverted to at least one human influenza strain, but there were no seroconversions to AI. Blood samples from all 717 birds tested were seronegative for influenza. CONCLUSION: Despite limited biosecurity there was no evidence of AI infection in participating backyard flocks or flock handlers.

Clinical characteristics and 30-day outcomes for influenza A 2009 (H1N1), 2008-2009 (H1N1), and 2007-2008 (H3N2) infections.

CONTEXT: The clinical characteristics of pandemic 2009 influenza A(H1N1) infections have not been compared directly with illnesses caused by other influenza A strains. OBJECTIVE: To compare clinical features and outcomes for 2009 H1N1, seasonal H1N1, and H3N2 influenza in a population-based cohort. DESIGN, SETTING, AND PARTICIPANTS: Active surveillance with 30-day follow-up for influenza cases among children and adults living in a 14-zip code area in Wisconsin. Patients with subjective fever, chills, or cough of fewer than 8 days' duration were screened for eligibility during an outpatient or inpatient encounter. Consenting patients were interviewed and tested for influenza A during the 2007-2008 and 2008-2009 influenza seasons and from May to November 2009; 6874 patients (70%-86% of eligible patients) agreed to participate. Medical records were reviewed to assess outcomes. MAIN OUTCOME MEASURES: Hospital admission, radiographically confirmed pneumonia, and clinical characteristics of influenza A by strain. RESULTS: We identified 545 2009 H1N1, 221 seasonal H1N1, and 632 H3N2 infections. The median ages of infected participants were 10, 11, and 25 years, respectively (P < .001). Hospital admission occurred within 30 days for 6 of 395 children with 2009 H1N1 (1.5%; 95% confidence interval [CI], 0.6%-3.1%), 5 of 135 with seasonal H1N1 (3.7%; 95% CI, 1.4%-8.0%), and 8 of 255 with H3N2 (3.1%; 95% CI, 1.5%-5.9%). Among adults, hospital admission occurred in 6 of 150 with 2009 H1N1 (4.0%; 95% CI, 1.6%-8.1%), 2 of 86 with seasonal H1N1 (2.3%; 95% CI, 0.3%-8.1%), and 17 of 377 with H3N2 (4.5%; 95% CI, 2.7%-7.0%). Pneumonia occurred in 10 children with 2009 H1N1 (2.5%; 95% CI, 1.3%-4.5%), 2 with seasonal H1N1 (1.5%; 95% CI, 0.2%-5.2%), and 5 with H3N2 (2.0%; 95% CI, 0.7%-4.3%). Among adults, pneumonia occurred in 6 with 2009 H1N1 (4.0%; 95% CI, 1.6%-8.1%), 2 with seasonal H1N1 (2.3%; 95% CI, 0.3%-8.1%), and 4 with H3N2 (1.1%; 95% CI, 0.3%-2.7%). CONCLUSIONS: In this population, individuals with 2009 H1N1 infection were younger than those with H3N2. The risk of most serious complications was not elevated in adults or children with 2009 H1N1 compared with recent seasonal strains.

A comparison of cardiovascular disease risk factors in farm and non-farm residents: the Wisconsin Rural Women's Health Study.

OBJECTIVES: The purpose of this paper is to describe the baseline difference in cardiovascular disease risk factors between farm and non-farm women in the Rural Women's Health Study. METHODS: Women aged 25 to 75 years were recruited from the Central Marshfield Epidemiologic Study Area, a geographically defined area surrounding Marshfield, Wis. (population 19,000), where more than 95% of residents seek their health care from the Marshfield Clinic. The baseline examination included measurements of blood pressure, skin folds, height, weight, fasting blood lipids, and blood glucose. Health behavior information collected included smoking, dietary intake, reproductive health, physical activity, medical history, social support, occupational strain and symptoms of anxiety and depression. RESULTS: Between 1995 and 2001, 825 non-farm residents and 675 farm residents were examined (58% of eligible women). The farm residents were similar in age to the non-farm residents (mean 47.6 years and 47.0 years, t-test = -0.91, P value = 0.36). The total number of modifiable risk factors for atherosclerosis ranged theoretically from 0 to 6, and actually from 0 to 5, with a small percentage of women having either none or 5 risk factors. The percentage of women with 3 or more modifiable risk factors was 26.1% (95% CL = 23.9, 28.4). The median number of total risk factors was 2 and the frequency distribution was not significantly different between farm and non-farm residents (chi 2 5 df = 4.6, P = 0.47). The prevalence of current cigarette smoking was significantly higher in the non-farm residents, while the prevalence of hypertension and obesity was significantly higher in the farm residents. Overall, obesity prevalence is significantly higher in the study cohort than US women in general (35% versus 23%). Only 5 (0.7%) of the farm residents and 10 (1.2%) of the non-farm residents reported a previous myocardial infarction. CONCLUSIONS: These data suggest that the prevalence of risk factors for atherosclerosis, and hence future coronary heart disease, is very high in rural women. Obesity prevention through increased physical activity would be appropriate for both farm and non-farm residents, while quit smoking campaigns should be specifically targeted towards non-farm resident women.