Dengue is a mosquito-borne viral disease that affects 40% of the world's population. Nearly four million U.S. citizens live in dengue-endemic areas; the most affected population resides in Puerto Rico. Data from a dengue surveillance system were used to describe all suspected cases reported in Puerto Rico in 2007. Rates of infection per 10,000 residents were calculated by age, sex, and residence. Rates and clinical outcomes were compared with those from outbreaks in 1994-1995 and 1998. In 2007, 10,508 suspected cases were reported; 52.5% persons were hospitalized, 31.8% reported hemorrhage, 2.2% had dengue hemorrhage fever, and 44 died. A total of 3,293 (33.0%) of processed specimens were laboratory positive for dengue virus (DENV); DENV-3 (1,342, 61.7%) and DENV-2 (677, 31.1%) were detected most often. The overall incidence of laboratory-positive dengue was 8.6 infections per 10,000 population. Rates were highest among persons 10-14 years of age (19.0), followed by persons 15-19 years of age (17.9) and infants (10.9). Higher rates of hospitalization and hemorrhage were reported in 2007 than in 1994-1995 or 1998. United States citizens residing in Puerto Rico are at risk of acquiring dengue. Data suggest that the severity is worsening, and persons 10-19 years of age and infants continue to be most affected.

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Millions of women of cild-bearing age have substantial bone lead stores due to lead exposure as children. Dietary calcium ingested simultaneously with lead eposure can reduce lead absorption and accumulaton. However, the efects of dietary calcium on previously accumulted maternal lead stores and transfer to the fetus have not been investigatedL We studied the effects oflead exposure of female rats at an early age on fetal development during a subsequent pregancy. We gave 5-weekold female Sprague-Dawley rats lead as the acetate in their ddnking water for 5 weeks; controls received equimolar sodium acetate. This was followed by a 1-month period without lead exposure before mating. We randomly assigned prewant rats (n = 39) to diets with a deficient (0.1%) or normal (0.5%) calcium content during pregnancy. A total of 345 pups were delivered alive. Leadexposed dams and their pups had significantly higher blood lead concentrations than controls, but the concentrations were in the range of those found in many pregnant women. Pups bom to dams fd the calcium-deficient diet during pregnancy had higher blood and organ lead concentrations than pups born to dams fed the 0.5% calcium diet. Pups bom to lead-exposed dams had sigificant- controls were simultaneously given equimolar sodium acetate in the drinking water. A 5-week period of lead exposure was followed by a 4-week period without lead exposure. During these periods before mating, the rats consumed diets containing 0.5% calcium. At this time, the rats were 14 weeks of age. The female rats were then mated with 14-weekold male SD rats, with 1 male and 3 females caged together. Of the 76 female rats, 39 (51.3%) were impregnated. Lead-exposed and nonexposed pregnant rats were then randomly assigned to either normal (0.5%) or low (0.1%) calcium diets during pregnancy. Nonpregnant animals were also randomly assigned to one of the calcium diets. We used a stratified design based on the blood lead concentration at the time of random assignment. This ensured comparable initial blood lead concentrations in the two lead-exposed treatment groups that were fed either 0.1% or 0.5% calcium. During pregnancy, dam body weights were measured twice each week. In addition, blood samples (150 pL) were drawn from a tail vein once each week.

Mild acutely presenting stroke patients are more likely to receive thrombolysis if they are young, white, or Hispanic and arrive early to the hospital with more severe neurological presentation. Identification of predictors of thrombolysis is important in design of future studies to assess the use of thrombolysis for mild stroke.