Individuals In Cambodia Research Articles

Protocol for a randomized controlled trial in Cambodian individuals with PTSD: Trauma-Informed Treatment Algorithms for Advancing Novel Outcomes (Project TITAN)

IntroductionLow- and middle-income countries shoulder a disproportionate burden of mental health disorders with limited resources to support the provision of care using culturally relevant, evidence-based interventions. This is particularly true in Cambodia where the population continues to confront traumatic consequences of the Khmer Rouge genocide that targeted educated people, including treatment providers. Trauma-Informed Treatment Algorithms for Advancing Novel Outcomes (Project TITAN) will examine proof of concept and preliminary efficacy of culturally tailored interventions for symptoms of post-traumatic stress (PTS) among Cambodian adults. MethodsA stepped care randomized controlled trial enrolling people seeking mental health treatment and priority populations with high rates of trauma exposure, including female entertainment and sex workers and sexual and gender minorities. In total, 160 participants with symptoms of PTS are randomized to Stabilization Techniques or Behavioral Activation plus Stabilization Techniques, implemented within a culturally relevant framework. Individuals who do not demonstrate a reduction in symptoms of PTS after six treatment sessions receive Eye Movement Desensitization and Reprocessing therapy. PTS, depression, anxiety, and substance use are assessed at baseline and two and four months post-randomization. Planned analysesThe percentage of individuals achieving reductions in symptoms of PTS after four months is the primary outcome. Secondary outcomes are depression, anxiety, and substance use over four months. Finally, machine learning analyses will be conducted to identify features at baseline and during treatment that predict outcomes. DiscussionFindings will guide future development and implementation of interventions to improve mental health conditions among individuals in Cambodia and other resource-limited settings.

Naturally acquired blocking human monoclonal antibodies to Plasmodiumvivax reticulocyte binding protein 2b

Plasmodium vivax preferentially invades reticulocytes and recognition of these cells is mediated by P. vivax Reticulocyte Binding Protein 2b (PvRBP2b) binding to human Transferrin receptor 1 (TfR1) and Transferrin (Tf). Longitudinal cohort studies in Papua New Guinea, Thailand and Brazil show that PvRBP2b antibodies are correlated with protection against P. vivax infection and disease. Here, we isolate and characterize anti-PvRBP2b human monoclonal antibodies from two individuals in Cambodia with natural P. vivax infection. These antibodies bind with high affinities and map to different regions of PvRBP2b. Several human antibodies block PvRBP2b binding to reticulocytes and inhibit complex formation with human TfR1-Tf. We describe different structural mechanisms for functional inhibition, including either steric hindrance with TfR1-Tf or the reticulocyte membrane. These results show that naturally acquired human antibodies against PvRBP2b can inhibit its function which is important for P. vivax invasion.

Correction: Understanding the prevalence of bear part consumption in Cambodia: A comparison of specialised questioning techniques.

[This corrects the article DOI: 10.1371/journal.pone.0211544.].

Factors influencing pre-marital sexual intercourse among unmarried young individuals in Cambodia

Background: Sexual behavior of young individual are recognized as one of the main health priority in society. In Cambodia, young individual who hasten to involve in sexual intercourse, contributes to their high risk of various health issues, particularly those related to sexual reproductive health. This research will identify specific characteristics that have strong relationships with pre-marital sexual intercourse among unmarried young individuals in Cambodia. Methods: A binary logistic regression in a multivariate analysis of secondary data was applied from the 2014 cambodian demographic and health survey. the data about pre-marital sexual intercourse were assessed with the CDHS questionnaire including as age, sex, education, place of resident, risky behavior, living arrangement, and exposure to mass media, knowledge about sexual and reproductive health and HIV prevention. Results: age (p = 0.000), sex (p = 0.000), place of residence (p = 0.000), staying away experience (p = 0.001), and smoking behavior (p = 0.000), were significantly associated with pre-marital sexual intercourse among unmarried young individuals. Conclusion: Appropriate reproductive health promotion programs and disease prevention strategies must be organized for target groups of young individuals who engage in pre-marital sexual intercourse. Moreover, comprehensive reproductive health education should be disseminated to increase awareness of risky sexual behavior and allow young individuals to make informed decisions regarding their sexual practices.

Understanding the prevalence of bear part consumption in Cambodia: A comparison of specialised questioning techniques

The trade in bear parts for medicine and for status is a conservation challenge throughout Asia. The Asiatic black bear (Ursus thibetanus) and the sun bear (Helarctos malayanus) are endemic to this region, and populations are estimated to have declined throughout their ranges due to widespread illegal killing of bears and trade in parts, combined with loss of habitat. Previous studies have indicated that legislation alone is insufficient to prevent illegal hunting and trade, indicating instead a need to address demand for bear parts and products. We conducted mixed-method surveys in Cambodia to understand the key motivators for individuals to consume bear parts, and to understand whether specialised questioning techniques are applicable in this context. Bear part use is illegal in Cambodia and may therefore be considered a sensitive behaviour, in that individuals may be reluctant to admit to it. To counteract possible biases, four specialised questioning techniques were used in this study: randomised response technique (RRT), unmatched count technique (UCT), nominative technique (NT), and false consensus bias (FCB). All four methods serve to shield a respondent’s admittance of a sensitive behaviour from the interviewer. The results presented here show that great variability exists in anonymous methods’ efficacy in certain contexts. However, the results overall indicate that individuals in Cambodia are under-reporting their consumption of bear parts when directly asked, and that the prevalence of bear part use in Cambodia may be as high as 15% of the population, representing a significant conservation challenge.

HIV Prevalence and Risks Associated with HIV Infection among Transgender Individuals in Cambodia.

IntroductionRecognizing transgender individuals have a high risk of HIV acquisition, and to inform policies and programming, we conducted an HIV prevalence and risk behaviors survey among transgender individuals in Cambodia.MethodsCross-sectional survey using a respondent driven sampling method with self-administered audio-computer assisted interviews. HIV testing was performed prior to the questionnaire with results available immediately after. Eligible participants were ≥18 years, identified as male at birth and self-identified/expressed as a different gender, and reported having sex with at least one male partner in past year. From six major urban centers of Cambodia, 891 transgender individuals were recruited.ResultsThe majority of the 891 participants self-identified as third gender or female (94.5%), were young (median age 23, IQR [20–27]), had secondary education or higher (80.5%), not married (89.7%), and employed (90.2%). The majority had first sex before 18 years (66.8%), with a male (79.9%), 37.9% having been paid or paying for this first sex. The rate of HIV positivity among participants was found to be 4.15%. Consistent condom use with male and female partners was low with all partner types, but particularly low with male partners when paying for sex (20.3%). The majority of participants reported having experienced discrimination in their lifetime (54.8%) and 30.3% had been assaulted. Multivariate analysis revealed that older age (adjusted OR = 14.73 [4.20, 51.67] for age 35–44 and adjusted OR = 7.63 [2.55, 22.81] for age 30–34), only having a primary school education or no schooling at all (adjusted OR = 2.62 [1.18, 5.80], being a resident of Siem Reap (adjusted OR = 7.44 [2.37,23.29], receiving payment at first sex (adjusted OR = 2.26 [1.00, 5.11], having sex during/after using drugs (adjusted OR = 2.90 [1.09,7.73]), inconsistent condom use during last anal sex (adjusted OR = 3.84 [1.58, 9.33]), and reporting low self-esteem (adjusted OR = 3.25 [1.35,7.85]) were independently associated with HIV infection.ConclusionsThis study confirms transgender individuals as one of the highest-risk groups for HIV infection in Cambodia. It suggests the need for programmatic strategies that mitigate identified associated risks and facilitate access to HIV care for this population.

The long-term effects of civil conflicts on education, earnings, and fertility: Evidence from Cambodia

This paper examines the long-term effects of exposure to civil war and genocide on the educational attainment, earnings, and fertility of individuals in Cambodia. Given the well-documented causal links between schooling and labor productivity, it is surprising that past studies show that civil conflicts reduce educational attainment, but generally not earnings of individuals. Using variation in the degree of Cambodians’ exposure to civil conflicts during primary school age, we find that disruption to primary education during civil conflicts decreases educational attainment and earnings, increases fertility, and has negligible effects on health of individuals several decades later. Our findings suggest that the effect of conflict on schooling disruption has adverse consequences on long-term labor productivity and economic development.

Extensive Within-Host Diversity in Fecally Carried Extended-Spectrum-Beta-Lactamase-Producing Escherichia coli Isolates: Implications for Transmission Analyses.

Studies of the transmission epidemiology of antimicrobial-resistant Escherichia coli, such as strains harboring extended-spectrum beta-lactamase (ESBL) genes, frequently use selective culture of rectal surveillance swabs to identify isolates for molecular epidemiological investigation. Typically, only single colonies are evaluated, which risks underestimating species diversity and transmission events. We sequenced the genomes of 16 E. coli colonies from each of eight fecal samples (n = 127 genomes; one failure), taken from different individuals in Cambodia, a region of high ESBL-producing E. coli prevalence. Sequence data were used to characterize both the core chromosomal diversity of E. coli isolates and their resistance/virulence gene content as a proxy measure of accessory genome diversity. The 127 E. coli genomes represented 31 distinct sequence types (STs). Seven (88%) of eight subjects carried ESBL-positive isolates, all containing blaCTX-M variants. Diversity was substantial, with a median of four STs/individual (range, 1 to 10) and wide genetic divergence at the nucleotide level within some STs. In 2/8 (25%) individuals, the same blaCTX-M variant occurred in different clones, and/or different blaCTX-M variants occurred in the same clone. Patterns of other resistance genes and common virulence factors, representing differences in the accessory genome, were also diverse within and between clones. The substantial diversity among intestinally carried ESBL-positive E. coli bacteria suggests that fecal surveillance, particularly if based on single-colony subcultures, will likely underestimate transmission events, especially in high-prevalence settings.

HIV-1 integrase variability and relationship with drug resistance in antiretroviral-naive and -experienced patients with different HIV-1 subtypes

H-932. American Society for Microbiology, Washington, DC, USA. 10 Nouhin J, Donchai T, Hoang KT et al. Natural polymorphisms of HIV-1 CRF01_AE integrase coding region in ARV-naive individuals in Cambodia, Thailand and Vietnam: an ANRS AC12 working group study. Infect Genet Evol 2011; 11: 38–43. 11 Wainberg MA, Brenner BG. Role of HIV subtype diversity in the development of resistance to antiviral drugs. Viruses 2010; 2: 2493–508. Research letter

Natural polymorphisms of HIV-1 CRF01_AE integrase coding region in ARV-naïve individuals in Cambodia, Thailand and Vietnam: An ANRS AC12 working group study

The HIV integrase enzyme is essential for the HIV life cycle as it mediates integration of HIV-1 proviral DNA into the infected cell's genome. Recently, the development of drugs capable of inhibiting integrase has provided major new options for HIV-infected, treatment-experienced patients with multidrug resistant virus, as well treatment-naïve patients. More than 40 amino acid substitutions within integrase have been described as associated mostly with resistance of HIV B-subtypes to currently available integrase inhibitors (INIs). We have analyzed the natural polymorphisms of the integrase coding region in 87 antiretroviral-naïve subjects (32 from Cambodia, 37 from Thailand and 18 from Vietnam) infected with CRF01_AE virus, the predominant HIV-1 strain circulating in Southeast Asia. The 864 bp integrase coding region was sequenced using the ANRS consensus sequencing technique from plasma samples, and amino acid results were interpreted for drug resistance according to the ANRS (Updated July 2009, version 18) and Stanford algorithms (Version November 6, 2009). Alignment of the 87 amino acid sequences against the 2004 Los Alamos HIV-1 clade B consensus sequence showed that overall, 119 of 288 (41.3%) amino acid positions presented at least one polymorphism each. Substitutions found in >60% of study subjects occurred at: K14, A21, V31, S39, I72, T112, T124, T125, G134, I135, K136, D167, V201, L234 and S283. Also, new amino acid substitutions of as yet unknown significance were identified: E152K/H, S153F/L, N155I and E157G. None of the known integrase resistance mutations were observed, except E157Q found in one Cambodian subject (1.1%, CI 95% 0.02–6.3%). The clinical impact of this substitution on resistance of B and nonB-viruses to the licensed INI raltegravir is unclear. If this substitution is confirmed to compromise the virologic response to raltegravir, further studies will be needed to better assess the prevalence of this substitution among CRF01_AE virus.

Natural Resistance to HIV Infection: Lessons Learned from HIV‐Exposed Uninfected Individuals

We explored potential mechanisms of resistance to human immunodeficiency virus type 1 (HIV‐1) infection in different groups of uninfected individuals exposed by systemic or mucosal routes: intravascular drug users in Vietnam and spouses of HIV‐infected individuals in Cambodia and Central African Republic. Our main findings were reduced susceptibility of peripheral blood mononuclear cells to HIV‐1 infection in vitro, associated with low levels of CD4+ T cell activation in vivo and/or cell restriction of viral replication, and enhanced natural killer cell activity, associated with increased ratios of activating to inhibitory natural killer cell receptors. These results support a contribution of innate responses to resistance against HIV‐1 infection. Scientific and ethical issues encountered during research in exposed uninfected subjects must be considered.

HIV-Specific Antibodies But Not T-Cell Responses Are Associated With Protection in Seronegative Partners of HIV-1-Infected Individuals in Cambodia

To study biological factors related to protection against HIV-1 infection in Cambodia, we recruited 48 partners of HIV-1-infected patients who remained uninfected (exposed uninfected individuals, EUs) despite unprotected sexual intercourse for more than 1 year and 49 unexposed controls (UCs). HIV-1-specific antibodies (IgA anti-gp41 and IgG anti-CD4-gp120 complex), T-cell responses, and cellular factors that may be involved in protection (peripheral blood mononuclear cell [PBMC] resistance to HIV-1 infection and beta-chemokine production) were evaluated. Anti-HIV-1 antibodies were higher in EUs than those in UCs (P = 0.01 and P = 0.04 for anti-gp41 and anti-CD4-gp120, respectively). We observed a decreased susceptibility to a primary Cambodian isolate, HIV-1KH019, in EU PBMCs as compared with UC PBMCs (P = 0.03). A weak T-cell response to one pool of HIV-1 Gag peptides was found by ELISpot in 1 of 19 EUs. Whereas T-cell specific immunity was not associated to protection, our results suggest that HIV-specific humoral immunity and reduced cell susceptibility to infection may contribute to protection against HIV-1 infection in Cambodian EUs.