A global systematic review of Chagas disease prevalence among migrants.

Human migration has been identified as a potential factor for increased Chagas disease risk and has transformed the disease from a Latin American problem to a global one. We conducted a systematic review of the scientific literature between 2004-2014 in order to: summarize recent seroprevalence estimates of Chagas disease among Latin American migrants, in both endemic and non-endemic settings; compare seroprevalence estimates in migrants to countrywide prevalence estimates; and identify risk factors for Chagas disease among migrants. A total of 320 studies were screened and 23 studies were included. We found evidence that the prevalence of Chagas disease is higher than expected in some migrant groups and that reliance on blood donor screening prevalence estimates underestimates the burden of disease. Overall there is a dearth of high quality epidemiologic studies on the prevalence of Chagas disease in migrants, especially among intra-regional migrants within Latin America. Given that this zoonotic disease cannot likely be eradicated, improved surveillance and reporting is vital to continuing control efforts. More accurate health surveillance of both Latin American migrants and the Chagas disease burden will help countries appropriately scale up their response to this chronic disease. Overall, improved estimates of Chagas disease among migrants would likely serve to highlight the real need for better screening, diagnostics, and treatment of individuals living with the disease

Structural factors associated with methamphetamine smoking among female sex workers in Tijuana, Mexico.

Introduction and aimsSmoking methamphetamine is associated with increased risk of HIV among female sex workers (FSW). The structural context of substance use is an important shaper of individual behaviour; however, structural determinants of methamphetamine use among FSWs are largely unknown. We identified individual, structural and neighbourhood factors associated with smoking methamphetamine among FSWs in the border city of Tijuana, Baja California, Mexico.Design and methodsA prospective cohort of 301 FSWs sampled from indoor and outdoor sex work venues throughout Tijuana participated in quantitative surveys on behaviours and mapping of home and work neighbourhoods across three visits. Multinomial logistic regression using generalised estimating equations identified individual, structural and neighbourhood variables associated with smoking methamphetamine.ResultsMethamphetamine use, particularly smoking, was highly prevalent among FSWs. Over half (61%) of FSWs had ever used methamphetamine in their lifetime and at baseline, 38% currently smoked methamphetamine. Smoking methamphetamine daily was associated with living in the red light district [adjusted odds ratio (AOR) = 2.72, 95% confidence interval (CI) = 1.23-6.02] and with perceived homelessness, but only among women in a good financial situation (AOR = 4.08, 95% CI = 1.58-10.50). Smoking methamphetamine less than daily was associated with older age (AOR = 1.06, 95% CI = 1.02-1.10).Discussion and conclusionsOur findings point to the important dynamic between the residential environment and more severe methamphetamine use. FSWs may prioritise the purchase of methamphetamine over stable housing if they have the financial means. Given the high prevalence of smoking methamphetamine among FSWs in Tijuana, drug treatment options, especially for women living in the red light district, are needed

Structural factors associated with methamphetamine smoking among female sex workers in Tijuana, Mexico.

Introduction and aimsSmoking methamphetamine is associated with increased risk of HIV among female sex workers (FSW). The structural context of substance use is an important shaper of individual behaviour; however, structural determinants of methamphetamine use among FSWs are largely unknown. We identified individual, structural and neighbourhood factors associated with smoking methamphetamine among FSWs in the border city of Tijuana, Baja California, Mexico.Design and methodsA prospective cohort of 301 FSWs sampled from indoor and outdoor sex work venues throughout Tijuana participated in quantitative surveys on behaviours and mapping of home and work neighbourhoods across three visits. Multinomial logistic regression using generalised estimating equations identified individual, structural and neighbourhood variables associated with smoking methamphetamine.ResultsMethamphetamine use, particularly smoking, was highly prevalent among FSWs. Over half (61%) of FSWs had ever used methamphetamine in their lifetime and at baseline, 38% currently smoked methamphetamine. Smoking methamphetamine daily was associated with living in the red light district [adjusted odds ratio (AOR) = 2.72, 95% confidence interval (CI) = 1.23-6.02] and with perceived homelessness, but only among women in a good financial situation (AOR = 4.08, 95% CI = 1.58-10.50). Smoking methamphetamine less than daily was associated with older age (AOR = 1.06, 95% CI = 1.02-1.10).Discussion and conclusionsOur findings point to the important dynamic between the residential environment and more severe methamphetamine use. FSWs may prioritise the purchase of methamphetamine over stable housing if they have the financial means. Given the high prevalence of smoking methamphetamine among FSWs in Tijuana, drug treatment options, especially for women living in the red light district, are needed

Cultivable Bacterial Diversity in the Gut of the Chagas Disease Vector Triatoma dimidiata: Identification of Possible Bacterial Candidates for a Paratransgenesis Approach

Since bacterial symbionts play a vital role in the metabolism of hematophagous insect vectors the method known as paratrangenesis, which consists of the use of cultivable insect symbionts to interfere with the transmission of vector-transmitted pathogens has been shown to be effective in certain vector control oriented studies. In Chagas disease research a recent study introduced transgenes through a parastransgenic approach and prevented the development of a vector species for this disease. However this approach requires a previous characterization of the bacterial symbionts present in the species vector of interest, since a selection of the cultivable bacterial symbiont used is mandatory. In this study, we describe the gut bacterial diversity of Triatoma dimidiata specimens from Southern Mexico. Bacteria from both wild and laboratory-reared specimens were cultured, and resulting colonies were grown individually, harvested, and subsequently identified by 16S ribosomal loci sequencing. A total of five and three genera and a total of nine and six bacterial species were identified from field captured and laboratory reared Triatoma dimidiata specimens respectively. A majority of Gram positive bacteria were identified, which included the genera Staphylococcus, Bacillus, Brevibacterium, Micrococcus, and Delftia. Given previous studies we propose the use of Staphylococcus saprophyticus, Micrococcus luteus, and Bacillus megaterium as potential candidates for future paratransgenic efforts done with Triatoma dimidiata, which is one of the most important vectors of Chagas disease, in Central and South America. Given the vital association bacterial symbionts play in the metabolism of routes of hematophagous insect vectors Paratransgenesis consists of the use of cultivable insect symbionts to interfere with the transmission of vector-transmitted pathogens

Protective association of colonoscopy against proximal and distal colon cancer and patterns in interval cancer

BackgroundThe protective effect of colonoscopy against proximal colorectal cancer is variable and depends on the detection and complete removal of precancerous polyps.ObjectiveTo estimate the efficacy of colonoscopy in a medical center with open-access screening colonoscopy since 1998.DesignNested case-control study with incidence density sampling.SettingUniversity-affiliated Veterans Affairs Medical Center.PatientsColorectal cancer (CRC) cases and control subjects selected from screening age patients matched by age, gender, and date of first primary care visit.Main outcome measurementColonoscopy preceding the CRC diagnosis date.ResultsA total of 20.2% of CRC cases had a colonoscopy in the preceding 10 years compared with 49.0% of control subjects (adjusted odds ratio [aOR], 0.20; 95% confidence interval [CI], 0.11-0.34). Colonoscopy was strongly associated with decreased odds of both distal CRC (aOR, 0.16; 95% CI, 0.07-0.34) and proximal CRC (aOR, 0.26; 95% CI, 0.11-0.58). The fraction of cases attributed to interval cancers was 10.5%. Missed lesions predominantly localized to the cecum and rectum, and recurrent lesions clustered in the hepatic flexure. Cecal intubation rate was 93% (98% in adequately prepped patients), and the adenoma detection rate was 45.2% in the control group.LimitationsSingle-center, retrospective case-control design.ConclusionIn an open access colonoscopy program characterized by a high cecal intubation rate and adenoma detection rate, colonoscopy was strongly associated with reduced odds of both distal and proximal CRC. Among interval cancers, missed lesions clustered in the cecum and rectum and recurrent lesions in the hepatic flexure

Structural Determinants of Client Perpetrated Violence Among Female Sex Workers in Two Mexico-U.S. Border Cities.

Female sex workers (FSWs) are disproportionately affected by both HIV and gender-based violence, such as that perpetrated by clients (CPV). We used a structural determinants framework to assess correlates of physical or sexual CPV in the past 6 months among FSWs in the Mexico/U.S. border cities of Ciudad Juárez and Tijuana. Bivariate and multivariate logistic regression analysis identified individual, client, interpersonal, work environment and macrostructural factors associated with recent CPV. Among 496 FSWs, 5 % experienced recent CPV. Witnessing violence towards other FSWs in one's neighborhood (aOR 5.6, 95 % CI 1.8-17.2), having a majority of foreign (aOR 3.5, 95 % CI 1.4-8.4) or substance using (aOR 4.0, 95 % CI 1.5-10.4) clients, and being a street worker (aOR 3.0, 95 % CI 1.1-7.7) were independently associated with recent CPV. Our findings underscore the vulnerability of FSWs and the need to design policies and interventions addressing macro-level influences on CPV rather than exclusively targeting individual behaviors