Host Correlates of Avian Influenza Virus Infection in Wild Waterfowl of the Sacramento Valley, California.

Avian influenza viruses (AIVs) are distributed globally in members of the family Anatidae (waterfowl), and significant disease may occur when these viruses infect commercial poultry or humans. Early detection of AIV through surveillance of wild waterfowl is one measure to prevent future disease outbreaks. Surveillance efforts that are designed to account for host and environmental determinants of susceptibility to infection are likely to be most effective. However, these determinants have not been clearly delineated and may vary with location. Because some regions are at greater risk for AIV outbreaks, the factors that contribute to AIV infection of waterfowl in these areas are of interest. We investigated the prevalence of AIVs in hunter-killed waterfowl at wintering sites in California's Central Valley. Overall, AIV prevalence was 10.5% and, after controlling for age and sex, was greatest in northern shovelers (Spatula clypeata) and lowest in wood ducks (Aix sponsa). Overall, AIV prevalence was higher in females than in males, but this trend was driven by one sampling year and one waterfowl species (green-winged teal, Anas crecca). AIV prevalence in waterfowl was lower in samples collected from brackish wetlands compared with those collected from freshwater wetlands, suggesting that wetland type or other environmental factors contribute to AIV prevalence. This study adds to our understanding of the ecology of AIV infection in waterfowl and may assist in developing more efficient, targeted surveillance efforts for the detection of potentially harmful viruses circulating in North American waterfowl.

Correlación de hospedadores en la infección por el virus de la influenza aviar en aves acuáticas silvestres del Valle de Sacramento en California. Los virus de la influenza aviar se distribuyen globalmente en miembros de la familia Anatidae (aves acuáticas) y pueden ocurrir enfermedades importantes cuando estos virus infectan aves comerciales o a los humanos. La detección temprana de los virus de influenza mediante la vigilancia de aves acuáticas silvestres es una medida para prevenir futuros brotes de enfermedades. Es probable que los esfuerzos de vigilancia diseñados para tener en cuenta los determinantes ambientales y del huésped para la susceptibilidad a la infección sean más eficaces. Sin embargo, estos determinantes no se han delineado claramente y pueden variar según la ubicación. Debido a que algunas regiones tienen un mayor riesgo de brotes de influenza aviar, los factores que contribuyen a la infección de las aves acuáticas en estas áreas son de interés. Se investigó la prevalencia de virus de influenza en aves acuáticas muertas por cazadores en sitios de estancia invernal en el Valle Central de California. En general, la prevalencia de los virus de influenza fue del 10.5% y, después de controlar por edad y sexo, fue mayor en los patos cuchara comunes del norte (Spatula clypeata) y más baja en los patos joyuyo (Aix sponsa). En general, la prevalencia de influenza fue mayor en las hembras que en los machos, pero esta tendencia fue influenciada por un año de muestreo y una especie de ave acuática (cerceta común, Anas crecca). La prevalencia de influenza aviar en aves acuáticas fue menor en las muestras recolectadas de humedales salobres en comparación con las recolectadas de humedales de agua dulce, lo que sugiere que el tipo de humedal u otros factores ambientales contribuyen a la prevalencia de los virus de influenza. Este estudio contribuye al conocimiento de la ecología en la infección por influenza aviar en las aves acuáticas y puede ayudar a desarrollar esfuerzos de vigilancia más eficientes y específicos para la detección de virus potencialmente dañinos que circulan en las aves acuáticas de América del Norte.

Effectiveness Evaluation of It's Your Game: Keep It Real, a Middle School HIV/Sexually Transmitted Infection/Pregnancy Prevention Program.

PURPOSE: This study assessed the effectiveness of the HIV/sexually transmitted infection/pregnancy prevention program, It's Your Game: Keep It Real (IYG). METHODS: IYG was implemented by classroom teachers in 24 urban middle schools from 2012 to 2015. Using a quasi-experimental design, each year we surveyed ninth-grade students in 10 high schools that were selected based on feeder patterns from project middle schools. We compared two groups of students (n = 4,562): (1) students whose middle school grade cohorts did not receive IYG ("No-IYG"), and (2) students whose middle school grade cohorts received IYG ("IYG"). Multilevel analyses examined differences between the two groups in the initiation of any type of sexual activity (oral, vaginal, or anal sex), presexual behaviors, and psychosocial mediators. RESULTS: Students in the IYG group were less likely to report initiation of sexual activity by ninth grade compared to students in the No-IYG group (odds ratio .77; 95% confidence interval .66-.90). The IYG group was significantly less likely to have engaged in presexual behaviors, including having been on a date, had a boyfriend/girlfriend, and touched or been touched on private body parts. The IYG group had better outcomes on 11 of 19 psychosocial variables, including knowledge; beliefs about abstinence, sex, friends' beliefs, norms, and behaviors; reasons for not having sex; personal limits; exposure to risky situations; self-efficacy; and quality of dating relationships. CONCLUSIONS: The results suggest that IYG, when implemented on a large scale by trained classroom teachers in urban public schools, had positive impacts on students' behaviors, beliefs, and knowledge.

Structural Intervention With School Nurses Increases Receipt of Sexual Health Care Among Male High School Students.

PURPOSE: Adolescent males are less likely to receive health care and have lower levels of sexual and reproductive health (SRH) knowledge than adolescent females. The purpose of this study was to determine if a school-based structural intervention focused on school nurses increases receipt of condoms and SRH information among male students. METHODS: Interventions to improve student access to sexual and reproductive health care were implemented in six urban high schools with a matched set of comparison schools. Interventions included working with school nurses to improve access to sexual and reproductive health care, including the provision of condoms and information about pregnancy and sexually transmitted disease prevention and services. Intervention effects were assessed through five cross-sectional yearly surveys, and analyses include data from 13,740 male students. RESULTS: Nurses in intervention schools changed their interactions with male students who visited them for services, such that, among those who reported they went to the school nurse for any reason in the previous year, those in intervention schools reported significant increases in receipt of sexual health services over the course of the study compared with students in comparison schools. Further, these results translated into population-level effects. Among all male students surveyed, those in intervention schools were more likely than those in comparison schools to report increases in receipt of sexual health services from school nurses. CONCLUSIONS: With a minimal investment of resources, school nurses can become important sources of SRH information and condoms for male high school students.

Patterns of Sexual Experience Among Urban Latino and African American Ninth Grade Students.

This analysis assessed patterns of sexual experience, the order in which behaviors were initiated, and associated factors, among Latino and African American ninth grade students (average age 15.2) who self-administered audio-computer-assisted surveys on netbooks in classes at 10 Los Angeles-area public high schools. Lifetime experiences with vaginal and oral sex were most common (19% and 16%, respectively); fewer reported anal sex (6%). Of the 23% reporting any sex, 91% fell into four categories: 36% reporting both oral and vaginal sex; 23% vaginal only; 18% all three; and 13% oral only. Most sexually experienced students (88%) initiated with vaginal or oral sex (46% vaginal, 33% oral, 9% both same day). No dominant pathway of sexual onset emerged for those reporting all three types of sex. We found no evidence that oral or anal sex substituted for or delayed vaginal sex. Males, those with a current partner, and those reporting multiple partners were more likely than others to report all three sexual behaviors versus vaginal only (odds ratios [ORs] 2.0, 1.5, 3.0; p = .02, .06, < .01, respectively). Although vaginal intercourse dominated their early sexual behavior, one-fifth of sexually experienced students reported anal intercourse, highlighting the need for specific prevention messages surrounding this higher-risk behavior.