Decline in HIV seroprevalence in street youth 2006-2012, St. Petersburg, Russia: moving toward an AIDS-free generation.

A 2006 survey of street youth at pre-mapped street youth locations in St. Petersburg, Russia, found extremely high HIV seroprevalence (37.4%) among 313 street youth aged 15-19 years of age, strongly associated with injection drug use, which was reported by 50.6% of participants. In response, multi-sectoral social support and prevention measures were instituted. In 2012, we conducted a follow-up survey of 15- to 19-year-old street youth using the same study procedures as in 2006. Of 311 participants, 45 (14.5%) reported injection drug use; 31 participants (10.0%, 95% confidence interval, 6.0%-16.2%) were HIV-seropositive . Predictors independently associated with HIV seropositivity included injection drug use (adjusted prevalence ratio 53.1) and transactional sex (adjusted prevalence ratio 1.3). None of the 178 participants aged 15-17 years were HIV-positive. Thirty of 31 (96.8%) HIV-seropositive individuals reported injection drug use. Street youth in St Petersburg had a 73% decrease in HIV seroprevalence from 2006 to 2012, primarily due to decreased initiation of injection drug use. This marked reduction in the HIV epidemic among street youth occurred after implementation of extensive support programs and socio-economic improvements.

Behaviors Associated With a Risk of HIV Transmission From HIV-Positive Street Youth to Non-Street Youth in Ukraine.

BACKGROUND: Little is known about the extent to which HIV-infected street youth (living part or full time on the streets) exhibit behaviors associated with HIV transmission in their interactions with youth not living on the streets ("non-street youth"). We aimed to determine prevalences and predictors of such "bridging behaviors": inconsistent condom use and needle sharing between HIV-positive street youth and non-street youth. METHODS: A total of 171 street youth in 3 Ukrainian cites were identified as HIV infected after testing of eligible participants aged 15 to 24 years after random selection of venues. Using data from these youth, we calculated prevalence estimates of bridging behaviors and assessed predictors using logistic regression. RESULTS: Overall, two-thirds of HIV-infected street youth exhibited bridging behaviors; subgroups with high prevalences of bridging included females (78.3%) and those involved in transactional sex (84.2%). In multivariable analysis, inconsistent condom use with non-street youth was associated with being female (adjusted prevalence ratio [aPR], 1.2; 95% confidence interval [CI], 1.1-1.4), working (aPR, 1.2; 95% CI, 1.03-1.4), multiple partners (aPR, 1.4; 95% CI, 1.2-1.6), and "never" (aPR, 1.4; 95% CI, 1.1-1.6) or "sometimes" (aPR, 1.3; 95% CI, 1.02-1.8) versus "always" sleeping on the street. Needle sharing with non-street youth was associated with being male (aPR, 1.4; 95% CI, 1.02-2.0), orphaned (aPR, 2.3; 95% CI, 1.8-3.0), and 2 years or less living on the streets (aPR, 1.8; 95% CI, 1.5-2.1). CONCLUSIONS: Bridging behaviors between HIV-infected street youth and non-street youth are common. Addressing the comprehensive needs of street and other at-risk youth is a critical prevention strategy.

Slowing of the HIV epidemic in Ukraine: evidence from case reporting and key population surveys, 2005-2012.

BACKGROUND: Ukraine developed Europe's most severe HIV epidemic due to widespread transmission among persons who inject drugs (PWID). Since 2004, prevention has focused on key populations; antiretroviral therapy (ART) coverage has increased. Recent data show increases in reported HIV cases through 2011, especially attributed to sexual transmission, but also signs of potential epidemic slowing. We conducted a data triangulation exercise to better analyze available data and inform program implementation. METHODS AND FINDINGS: We reviewed data for 2005 to 2012 from multiple sources, primarily national HIV case reporting and integrated biobehavioral surveillance (IBBS) studies among key populations. Annually reported HIV cases increased at a progressively slower rate through 2011 with recent increases only among older, more immunosuppressed individuals; cases decreased 2.7% in 2012. Among women <25 years of age, cases attributed to heterosexual transmission and HIV prevalence in antenatal screening declined after 2008. Reported cases among young PWID declined by three-fourths. In 2011, integrated biobehavioral surveillance demonstrated decreased HIV prevalence among young members of key populations compared with 2009. HIV infection among female sex workers (FSW) remains strongly associated with a personal history of injecting drug use (IDU). CONCLUSIONS: This analysis suggests that Ukraine's HIV epidemic has slowed, with decreasing reported cases and older cases predominating among those diagnosed. Recent decreases in cases and in prevalence support decreased incidence among young PWID and women. Trends among heterosexual men and men who have sex with men (MSM) are less clear; further study and enhanced MSM prevention are needed. FSW appear to have stable prevalence with risk strongly associated with IDU. Current trends suggest the Ukrainian epidemic can be contained with enhanced prevention among key populations and increased treatment access.

Trends in pertussis among infants in the United States, 1980-1999.

CONTEXT: Reported cases of pertussis among adolescents and adults have increased since the 1980s, despite increasingly high rates of vaccination among infants and children. However, severe pertussis morbidity and mortality occur primarily among infants. OBJECTIVE: To describe the trends and characteristics of reported cases of pertussis among infants younger than 12 months in the United States from 1980 to 1999. DESIGN, SETTING, AND PARTICIPANTS: Cases of pertussis in infants younger than 12 months in the United States reported to the National Notifiable Disease Surveillance System of the Centers for Disease Control and Prevention between 1980 and 1999, and detailed case data from the Supplementary Pertussis Surveillance System. MAIN OUTCOME MEASURES: Incidence and demographic and clinical characteristics of cases. RESULTS: The incidence of reported cases of pertussis among infants increased 49% in the 1990s compared with the incidence in the 1980s (19 798 vs 12 550 cases reported; 51.1 cases vs 34.2 cases per 100 000 infant population, respectively). Increases in the incidence of cases and the number of deaths among infants during the 1990s primarily were among those aged 4 months or younger, contrasting with a stable incidence of cases among infants aged 5 months or older. The proportion of cases confirmed by bacterial culture was higher in the 1990s than in the 1980s (50% and 33%, respectively); the proportion of hospitalized cases was unchanged (67% vs 68%, respectively). Receipt of fewer doses of vaccine was associated with hospitalization, when cases were stratified by age in months. CONCLUSIONS: The incidence of reported cases of pertussis among infants increased in the 1990s compared with the 1980s. The limited age group affected, the increased rate of bacteriologic confirmation, and the unchanged severity of illness suggest that an increase in infant pertussis has occurred apart from any change in reporting. Strategies are needed to prevent the morbidity and mortality from pertussis among infants too young to be fully vaccinated, according to the current recommended schedules of vaccination in the United States.

Increase in deaths from pertussis among young infants in the United States in the 1990s.

BACKGROUND: Severe pertussis primarily occurs among infants (<12 months of age). Despite high levels of immunization, reported pertussis cases increased in the United States in the 1990s among all age groups, including infants. METHODS: To characterize fatal pertussis cases, we analyzed pertussis deaths reported to CDC in the 1990s and compared these with data on pertussis deaths reported in the 1980s. Data from national surveillance systems and from available medical records were used, including data from analyses of deaths reported in 1992 through 1995. RESULTS: In 1980 through 1989, 77 pertussis deaths were reported; 61 deaths were among infants (1.67 deaths per million), including 49 among infants <4 months of age. In the 1990s 103 pertussis deaths were reported; 93 deaths were among infants (2.40 deaths per million), including 84 among infants <4 months of age. Of 89 infants with ethnicity data, 31 (36%) were Hispanic; the mortality rate among Hispanic infants (4.77 per million) was higher than among non-Hispanic infants (1.80 per million). Of 76 infants with reported gestational age, 40 (53%) were born at <37 weeks, including 22 (29%) who were born at <35 weeks. Severe pulmonary hypertension was a common lethal complication among infants. CONCLUSIONS: Pertussis deaths increased among infants too young to be protected by immunization. A disproportionate share of deaths were complicated by pulmonary hypertension and occurred among Hispanic infants and infants born at <37 weeks gestation. New approaches to prevent infection among infants <4 months of age and improved therapies for pertussis complications are needed.

Key issues for a potential human immunodeficiency virus vaccine.

A safe, effective, and affordable vaccine remains the best long-term hope for bringing the global human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) epidemic under control. Recent scientific developments have suggested that the first generation of HIV vaccines available for public health care use will likely be of low to moderate efficacy, compared with currently licensed vaccines for other diseases. Nevertheless, such "partially effective" HIV vaccines could provide considerable individual and public health benefits. A consultation was held in January 2002 to advise the Centers for Disease Control and Prevention (Atlanta, Georgia) about critical issues that need to be addressed in anticipation of the eventual licensure and availability of an HIV vaccine in the United States. The present article summarizes the major issues discussed at the consultation with regard to the potential use of a partially effective vaccine in HIV prevention programs in the United States and the activities that are needed to prepare for vaccine availability.