Objectives To examine the relationship between nonmedical use of prescription opioids and heroin initiation from childhood to young adulthood, and to test whether certain ages, racial/ethnic, and income groups were at higher risk for this transition. Study design Among a nationally representative sample of US adolescents assessed in the 2004-2011 National Surveys on Drug Use and Health cross-sectional surveys (n = 223 534 respondents aged 12-21 years), discrete-time hazard models were used to estimate the age-specific hazards of heroin initiation associated with prior history of nonmedical use of prescription opioids. Interactions were estimated between prior history of nonmedical use of prescription opioids and age of nonmedical use of prescription opioid initiation, race/ethnicity, and income. Results A prior history of nonmedical use of prescription opioids was strongly associated with heroin initiation (hazard ratio 13.12, 95% CI 10.73, 16.04). Those initiating nonmedical use of prescription opioids at ages 10-12 years had the highest risk of transitioning to heroin use; the association did not vary by race/ethnicity or income group. Conclusions Prior use of nonmedical use of prescription opioids is a strong predictor of heroin use onset in adolescence and young adulthood, regardless of the user's race/ethnicity or income group. Primary prevention of nonmedical use of prescription opioids in late childhood may prevent the onset of more severe types of drug use such as heroin at later ages. Moreover, because the peak period of heroin initiation occurs at ages 17-18 years, secondary efforts to prevent heroin use may be most effective if they focus on young adolescents who already initiated nonmedical use of prescription opioids.

Background-Little is known about the relationship of stressful life events and alcohol craving in the general population, and whether a history of childhood maltreatment sensitizes individuals to crave alcohol after adult stressors.

Abstract. Peridomestic transmission of American cutaneous leishmaniasis is increasingly reported and dogs may be a reservoir of Leishmania ( Viannia ) in this setting. We investigated the prevalence of infection in dogs in Chaparral County, Colombia, the focus of an epidemic of human cutaneous leishmaniasis caused by Leishmania ( Viannia ) guyanensis . Two (0.72%) of 279 dogs had lesions typical of cutaneous leishmaniasis that were biopsy positive by kinetoplast DNA polymerase chain reaction-Southern blotting. Seroprevalence was 2.2% (6 of 279) by enzyme-linked immunosorbent assay. Buffy coat and ear skin biopsy specimens were positive by polymerase chain reaction-Southern blotting in 7.3% (10 of 137) and 11.4% (12 of 105) of dogs, respectively. Overall 20% of dogs (21 of 105) showed positive results for one or more tests. Amplification and sequencing of the Leishmania 7SL RNA gene identified L. guyanensis in one dog and L. braziliensis in two dogs. No association was identified between the risk factors evaluated and canine infection. Dogs may contribute to transmission but their role in this focus appears to be limited.

Sera from white-tailed deer (Odocoileus virginianus) were collected in Iowa during the winter months (1999-2003), 2 years before and after West Nile virus (WNV) was first reported in Iowa (2001), and were analyzed for antibodies to WNV. Samples from 1999 to 2001 were antibody negative by blocking enzyme-linked immunosorbent assay (bELISA) and plaque reduction neutralization test (PRNT(90)). Prevalence derived from bELISA (2002, 12.7%; 2003, 11.2%) and WNV PRNT(90) (2002, 7.9%; 2003, 8.5%) assays were similar. All samples were negative for antibodies against St. Louis encephalitis virus as determined by PRNT(90). Antibodies to flaviviruses were detected by indirect enzyme-linked immunosorbent assay (iELISA) prior to the first WNV cases reported in Iowa (1999-2001) with prevalence ranging from 2.2% to 3.2%, suggesting the circulation of an additional undescribed flavivirus prior to the introduction of WNV into the area. Flavivirus prevalence as determined by iELISA increased in 2002 and 2003 (23.3% and 31.9%, respectively). The increase in prevalence exceeded estimates of WNV prevalence, suggesting that conditions favored general flavivirus transmission (including WNV) during the 2002-2003 epizootic. These data indicate that serologic analysis of deer sera collected from hunter harvests may prove useful for surveillance and evidence of local transmission of WNV and other pathogens and identify white-tailed deer as a species for further studies for host competency.

Objective To document the natural course of sensation seeking from childhood to adolescence, characterize distinct sensation-seeking trajectories, and examine how these trajectories vary according to selected predictors. Method Data were obtained from the Boricua Youth Study, a longitudinal study of 2,491 children and adolescents of Puerto Rican background (three assessments from 2000 to 2004). First, age-specific sensation-seeking levels were characterized. Then, age-adjusted residuals were analyzed using growth mixture models (GMM). Results On average, sensation seeking was stable in childhood (ages 5–10) and increased during adolescence (ages 11–17). Mean scores of sensation seeking were higher in the South Bronx vs. Puerto Rico and among males vs. females. Four classes of sensation-seeking trajectories were observed: most study participants had age-expected sensation-seeking trajectories following the average for their age (“normative,” 43.8%); others (37.2%) remained consistently lower than the expected average for their age (“low” sensation seeking); some (12.0%) had an “accelerated” sensation-seeking trajectory, increasing at a faster rate than expected, while a minority (7.0%) had a decreasing sensation-seeking trajectory that started high but decreased, reaching scores slightly higher than the age-average sensation-seeking scores (“stabilizers”). Site (South Bronx vs. Puerto Rico) and gender were predictors of membership in a specific class of sensation-seeking trajectory. Conclusion It is important to take a developmental approach when examining sensation seeking and to consider gender and the social environment when trying to understand how sensation seeking evolves during childhood and adolescence.