Transitions from Injection-Drug-Use-Concentrated to Self-Sustaining Heterosexual HIV Epidemics: Patterns in the International Data

Background: Injecting drug use continues to be a primary driver of HIV epidemics in many parts of the world. Many people who inject drugs (PWID) are sexually active, so it is possible that high-seroprevalence HIV epidemics among PWID may initiate self-sustaining heterosexual transmission epidemics. Methods: Fourteen countries that had experienced high seroprevalence (,20%) HIV epidemics among PWID and had reliable data for injection drug use (IDU) and heterosexual cases of HIV or AIDS were identified. Graphs of newly reported HIV or AIDS cases among PWID and heterosexuals were constructed to identify temporal relationships between the two types of epidemics. The year in which newly reported cases among heterosexuals surpassed newly reported cases among PWID, aspects of the epidemic curves, and epidemic case histories were analyzed to assess whether it was ‘‘plausible’ ’ or ‘‘highly unlikely’ ’ that the HIV epidemic among PWID might have initiated the heterosexual epidemic in each country. Results: Transitions have occurred in 11 of the 14 countries. Two types of temporal relationships between IDU and heterosexual HIV epidemics were identified, rapid high incidence transitions vs. delayed, low incidence transitions. In six countries it appears ‘‘plausible’ ’ that the IDU epidemic initiated a heterosexual epidemic, and in five countries it appears ‘‘highly unlikely’ ’ that the IDU epidemic initiated a heterosexual epidemic. A rapid decline in incidence among PWID after the peak year of new cases and national income were the best predictors of the ‘‘highly unlikely’ ’ initiation of a heterosexua

High coverage needle/syringe programs for people who inject drugs in low and middle income countries: a systematic review

BACKGROUND: Persons who inject drugs (PWID) are at an elevated risk for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infection. In many high-income countries, needle and syringe exchange programs (NSP) have been associated with reductions in blood-borne infections. However, we do not have a good understanding of the effectiveness of NSP in low/middle-income and transitional-economy countries. METHODS: A systematic literature review based on PRISMA guidelines was utilized to collect primary study data on coverage of NSP programs and changes in HIV and HCV infection over time among PWID in low-and middle-income and transitional countries (LMICs). Included studies reported laboratory measures of either HIV or HCV and at least 50% coverage of the local injecting population (through direct use or through secondary exchange). We also included national reports on newly reported HIV cases for countries that had national level data for PWID in conjunction with NSP scale-up and implementation. RESULTS: Studies of 11 NSPs with high-coverage from Bangladesh, Brazil, China, Estonia, Iran, Lithuania, Taiwan, Thailand and Vietnam were included in the review. In five studies HIV prevalence decreased (range −3% to −15%) and in three studies HCV prevalence decreased (range −4.2% to −10.2%). In two studies HIV prevalence increased (range +5.6% to +14.8%). HCV incidence remained stable in one study. Of the four national reports of newly reported HIV cases, three reported decreases during NSP expansion, ranging from −30% to −93.3%, while one national report documented an increase in cases (+37.6%). Estimated incidence among new injectors decreased in three studies, with reductions ranging from −11/100 person years at risk to −16/100 person years at risk. CONCLUSIONS: While not fully consistent, the data generally support the effectiveness of NSP in reducing HIV and HCV infection in low/middle-income and transitional-economy countries. If high coverage is achieved, NSP appear to be as effective in LMICs as in high-income countries. Additional monitoring and evaluation research is needed for NSPs where reductions in HIV/HCV infection among PWID are not occurring in order to identify and correct contributing problems

Special Characteristics and Transition Types by Country.

<p>*From literature search.</p><p>**Persistence is operationally defined as less than a 30% decline in new IDU cases around the transition period or over the 3 year span after the peak in IDU cases.</p

Stage-specific Localization and Expression of c-kit in the Adult Human Testis

The c-kit receptor (KIT) and its ligand, stem cell factor (SCF), represent one of the key regulators of testicular formation, development, and function and have been extensively studied in various animal models. The present study was undertaken to characterize the pattern of localization and expression of c-kit in normal adult human testis. Immunohistochemical analysis showed that KIT is expressed in the cytoplasm of spermatogonia, acrosomal granules of spermatids, and Leydig cells. Interestingly, a rather heterogenous pattern of expression of the protein along the basement membrane was observed. Intense protein localization in spermatogonia was detected in stages I–III, whereas low expression was observed in stages IV–VI of the seminiferous epithelium, indicating that the expression of the molecule was stage specific. In situ hybridization studies revealed that the transcripts of the gene were also localized in a similar non-uniform pattern. To the best of our knowledge, such a stage-specific expression of KIT has not been reported previously in the human testis. The results of the present study may expand current knowledge about the c-kit/SCF system in human spermatogenesis. (J Histochem Cytochem 57:861–869, 2009