ABSTRACT
From 2011 through 2018, there was a notable increase in sporadic Legionnaires' disease in the state of Minnesota. Sporadic cases are those not associated with a documented outbreak. Outbreak-related cases are typically associated with a common identified contaminated water system; sporadic cases typically do not have a common source that has been identified. Because of this, it is hypothesised that weather and environmental factors can be used as predictors of sporadic Legionnaires' disease. An ecological design was used with case report surveillance data from the state of Minnesota during 2011 through 2018. Over this 8-year period, there were 374 confirmed Legionnaires' disease cases included in the analysis. Precipitation, temperature and relative humidity (RH) data were collected from weather stations across the state. A Poisson regression analysis examined the risk of Legionnaires' disease associated with precipitation, temperature, RH, land-use and age. A lagged average 14-day precipitation had the strongest association with Legionnaires' disease (RR 2.5, CI 2.1-2.9), when accounting for temperature, RH, land-use and age. Temperature, RH and land-use also had statistically significant associations to Legionnaires' disease, but with smaller risk ratios. This study adds to the body of evidence that weather and environmental factors play an important role in the risk of sporadic Legionnaires' disease. This is an area that can be used to target additional research and prevention strategies.
Subject(s)
Legionnaires' Disease/epidemiology , Legionnaires' Disease/etiology , Weather , Adult , Aged , Disease Outbreaks , Female , Humans , Male , Middle Aged , Minnesota/epidemiology , Retrospective Studies , Water Microbiology , Young AdultABSTRACT
OBJECTIVE: To describe the epidemiology and clinical spectrum of reactive arthritis (ReA) following culture-confirmed infection with bacterial enteric pathogens in a population-based study in the USA. METHODS: We conducted telephone interviews of persons age>1 year with culture confirmed Campylobacter, Escherichia coli O157, Salmonella, Shigella and Yersinia infections reported to FoodNet (http://www.cdc.gov/FoodNet/) in Minnesota, USA and Oregon, USA between 2002 and 2004. SUBJECTS: with new onset joint pain, joint swelling, back pain, heel pain and morning stiffness lasting >or=3 days within 8 weeks of culture (possible ReA) were invited to complete a detailed questionnaire and physical examination. RESULTS: A total of 6379 culture-confirmed infections were reported; 70% completed screening interviews. Of these, 575 (13%) developed possible ReA; incidence was highest following Campylobacter (2.1/100,000) and Salmonella (1.4/100,000) infections. Risk was greater for females (relative risk (RR) 1.5, 95% CI, 1.3 to 1.7), adults (RR 2.5, 95% CI, 2.0 to 3.1) and subjects with severe acute illness (eg, fever, chills, headache, persistent diarrhoea). Risk was not associated with antibiotic use or human leukocyte antigen (HLA)-B27. A total of 54 (66%) of 82 subjects examined had confirmed ReA. Enthesitis was the most frequent finding; arthritis was less common. The estimated incidence of ReA following culture-confirmed Campylobacter, E coli O157, Salmonella, Shigella and Yersinia infections in Oregon was 0.6-3.1 cases/100,000. CONCLUSIONS: This is the first population-based study of ReA following infections due to bacterial enteric pathogens in the USA. These data will help determine the burden of illness due to these pathogens and inform clinicians about potential sequelae of these infections.
Subject(s)
Arthritis, Reactive/epidemiology , Enterobacteriaceae Infections/epidemiology , Acute Disease , Adolescent , Adult , Age Distribution , Arthritis, Reactive/microbiology , Campylobacter Infections/epidemiology , Child , Child, Preschool , Epidemiologic Methods , Female , Humans , Infant , Male , Minnesota/epidemiology , Oregon/epidemiology , Physical Examination/methods , Prohibitins , Salmonella Infections/epidemiology , Sex Distribution , Young AdultABSTRACT
The lubrication properties of two commercial-grade magnesium stearates were studied. Their moisture contents and crystal structures were similar. There were minor differences in their fatty acid composition, but the differences did not affect the lubrication properties. The lubrication properties correlated with particle size distributions and specific surface area. The effect of these parameters was further studied with unmilled and milled chemically pure magnesium stearate. Milling decreased the particle size and increased the specific surface area. In both cases, the batch with a smaller particle size and larger specific surface area had considerably better lubricity.
