A large case-control study indicates a breed-specific predisposition to feline tooth resorption.

Tooth resorption (TR) is one of the most common dental diseases of cats. It is a painful condition leading to tooth loss. The etiology of TR remains unclear, but old age, breed, other oral and dental diseases, and environmental factors are suspected predisposing factors. In our study, we used part of the data from the extensive feline health online survey of 8115 Finnish cats. As TR is difficult to detect and as the feline health survey included diagnoses defined by both veterinarians and the owners, we limited our study to a subpopulation of cats diagnosed with oral or dental disease by a veterinarian and had dental examination or surgery under sedation (n=944). We utilized case-control study analysed by multivariable logistic regression to determine the risk factors and breed variation of feline TR. The 202 cats diagnosed with TR were defined as TR cases and the remaining 742 cats as controls. The frequency of veterinarian-diagnosed TR was 3.9% in the health survey data (316/8115) and 21% in the subpopulation (202/944). The risk of TR increased with age (14.7% in youngest and 25.3% in oldest age group). Our finding that TR was significantly associated with gingivitis or periodontitis in cats that had also calculus (OR: 2.49 and 3.70, respectively) suggests that inflammatory changes caused by calculus increase the risk of TR. We found that Cornish Rex, European, and Ragdoll are at higher risk for TR (OR: 2.44, 2.98 and 2.90, respectively). Exotic-Persians breed group had lower risk (OR: 0.28). TR was not observed in Turkish van or Devon Rex. The differences between breeds highlight a genetic contribution. In addition, female cats that had food available constantly had significantly less TR than female cats that had feeding times (OR: 0.44). The underlying reasons for this remain unexplained in our study.

Case-control study on Puumala virus infection: smoking is a risk factor.

Puumala hantavirus (PUUV) is apparently transmitted to humans by inhalation of aerosolized secretions of carrier rodents (bank voles). The means of transmission and the associated risk factors are poorly defined. An epidemiological study during the peak of an epidemic season in Finland was conducted based on 282 acute clinical PUUV infections and 204 controls without PUUV infection or immunity. The main risk factors adjusted by age, sex and living environment were cigarette smoking [odds ratio (OR) 3.6, 95% confidence interval (CI) 2.1-5.9, P<0.0001] and buildings with holes allowing rodents to enter (OR 3.3, 95% CI 2.0-5.6); these results were similar in two subsets. Further, use of rodent traps (OR3.5, 95% CI 2.2-5.7) and handling firewood (OR 2.7, 95% CI 1.6-4.4) were associated with a risk. The risk attributed to smoking also remained high using simulated population controls with average smoking habits. The results suggest that hantavirus transmission occurs by inhalation mainly indoors and is dependent on the condition of the respiratory tract.

Puumala virus infections in Finland: increased occupational risk for farmers.

Puumala hantavirus, transmitted by bank voles (Clethrionomys glareolus), causes a mild-type hemorrhagic fever with renal syndrome. The disease is common in Finland and is considered an occupational hazard for farmers, but the actual risk has not been assessed by analytical studies. Data on 5,132 serologically confirmed Puumala virus infections during 1989-1994 were analyzed, and cases among farmers and the population living in similar conditions were compared. The farmers contracted the disease earlier and more often than did the comparison group. In the province of Mikkeli with the highest incidence (70/100,000), the risk ratio was 5.1 (95% confidence interval (CI) 3.0-8.4) for 20- to 29-year-old farmers; in the older age groups, the risk was still increased but the risk ratios were lower. The peak incidence in the comparison group was 10 years later (age group 30-39 years). For the whole country, the result was similar although less marked. The average risk ratio adjusted by age, sex, and geographic variation was 1.7 (95% CI 1.5-1.8) for the whole country and 1.9 (95% CI 1.5-2.3) for the Mikkeli province, where 80% of Puumala virus infections among young farmers could be estimated to be attributable to occupation.