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Background: The wMel strain of Wolbachia has been successfully introduced into Aedes aegypti mosquitoes and has been shown to reduce the transmission of dengue and other Aedes-borne viruses. Here we report the entomological results from phased, large-scale releases of Wolbachia infected Ae. aegypti mosquitoes throughout three contiguous cities located in the Aburrá Valley, Colombia. Methodology/principal findings: Local wMel Wolbachia-infected Ae. aegypti mosquitoes were generated and then released in an initial release pilot area in 2015–2016, which resulted in the establishment of Wolbachia in the local mosquito populations. Subsequent large-scale releases, mainly involving vehicle-based releases of adult mosquitoes along publicly accessible roads and streets, were undertaken across 29 comunas throughout Bello, Medellín and Itagüí Colombia between 2017–2022. In 9 comunas these were supplemented by egg releases that were undertaken by staff or community members. By the most recent monitoring, Wolbachia was found to be stable and established at consistent levels in local mosquito populations (>60% prevalence) in the majority (67%) of areas. Conclusion: These results, from the largest contiguous releases of wMel Wolbachia mosquitoes to date, highlight the operational feasibility of implementing the method in large urban settings. Based on results from previous studies, we expect that Wolbachia establishment will be sustained long term. Ongoing monitoring will confirm Wolbachia persistence in local mosquito populations and track its establishment in the remaining areas. Author summary: The introduction of the naturally occurring wMel Wolbachia strain into Aedes aegypti mosquitoes has been shown to reduce the ability of the mosquitoes to transmit dengue and other viruses. Following engagement with communities to gain acceptance and support, a series of large-scale releases of Ae. aegypti mosquitoes that contained wMel Wolbachia, were undertaken across the cities of Bello, Medellín and Itagüí in Colombia. These releases were undertaken under operational conditions with the aim of rapidly scaling the intervention in response to the Zika virus crisis. Mosquito populations were monitored during and after releases to determine the levels of Wolbachia and whether it persisted in the local mosquitoes. Wolbachia was found to be stable and established at consistent levels in local mosquito populations in the majority of areas. On-going monitoring in these areas will determine whether Wolbachia persists and also whether it establishes at a high level in the remaining areas. This intervention forms the basis of an epidemiological study to assess the impact of operational deployment of wMel Wolbachia on the reduction of the incidence of notified dengue cases and virologically-confirmed dengue. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Medicine & International Health is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective:To determine the incidence of pulmonary tuberculosis (TB) in inmates, factors associated with TB, and the time to sputum smear and culture conversion during TB treatment. Methods:Prospective cohort study. All prisoners with respiratory symptoms (RS) of any duration were evaluated. After participants signed consent forms, we collected three spontaneous sputum samples on consecutive days. We performed auramine-rhodamine staining, culturing with the thin-layer agar method, Löwestein-Jensen medium and MGIT, susceptibility testing for first-line drugs; and HIV testing. TB cases were followed, and the times to smear and culture conversion to negative were evaluated. Results:Of 9,507 prisoners held in four prisons between April/30/2010 and April/30/2012, among them 4,463 were screened, 1,305 were evaluated for TB because of the lower RS of any duration, and 72 were diagnosed with TB. The annual incidence was 505 cases/100,000 prisoners. Among TB cases, the median age was 30 years, 25% had <15 days of cough, 12.5% had a history of prior TB, and 40.3% had prior contact with a TB case. TB-HIV coinfection was diagnosed in three cases. History of prior TB, contact with a TB case, and being underweight were risk factors associated with TB. Overweight was a protective factor. Almost a quarter of TB cases were detected only by culture; three cases were isoniazid resistant, and two resistant to streptomycin. The median times to culture conversion was 59 days, and smear conversion was 33. Conclusions:The TB incidence in prisons is 20 times higher than in the general Colombian population. TB should be considered in inmates with lower RS of any duration. Our data demonstrate that patients receiving adequate anti-TB treatment remain infectious for prolonged periods. These findings suggest that current recommendations regarding isolation of prisoners with TB should be reconsidered, and suggest the need for mycobacterial cultures during follow-up. [ABSTRACT FROM AUTHOR]

Summary Objectives To evaluate the concordance and safety of induced sputum (IS) and spontaneous sputum (SS), and estimate concordance and time to detection of M. tuberculosis between Lowenstein–Jensen (LJ), thin-layer agar (TLA), and the Mycobacteria Growth Indicator Tube system (MGIT). Methods This was a cohort study. Prisoners with pulmonary tuberculosis (PTB) were followed for 2 years. At baseline and every follow-up visit, three sputum samples were taken on consecutive days (one IS and two SS) and adverse events occurring before, during, and 30 min after IS were registered. All sputum samples were stained with auramine and cultured in LJ, TLA (to test resistance), and MGIT. Results Five hundred eighty-six IS and 532 SS were performed on 64 PTB patients. Breathlessness (1.6%), cough (1.2%), hemoptysis (0.3%), and cyanosis (0.2%) were the only complications. Concordance between IS and SS was 0.78 (95% confidence interval 0.69–0.87); 11 positive cultures from IS samples were negative in SS, and 11 positive cultures from SS samples were negative in IS. One hundred seventy-eight cultures were positive by any technique: MGIT 95%, LJ 73%, and TLA 57%. Time to detection of M. tuberculosis in LJ, TLA, and MGIT was 31, 18, and 11 days, respectively. Conclusions The IS procedure is safe in prisons. The MGIT system is better and faster than LJ and TLA in the diagnosis of M. tuberculosis . [ABSTRACT FROM AUTHOR]

People deprived of liberty (PDL) are at high risk of acquiring Mycobacterium tuberculosis infection (latent tuberculosis infection [LTBI]) and progressing to active tuberculosis (TB). We sought to determine the incidence rates and factors associated with LTBI and active TB in Colombian prisons. Using information of four cohort studies, we included 240 PDL with two-step tuberculin skin test (TST) negative and followed them to evaluate TST conversion, as well as, 2,134 PDL that were investigated to rule out active TB (1,305 among people with lower respiratory symptoms of any duration, and 829 among people without respiratory symptoms and screened for LTBI). Latent tuberculosis infection incidence rate was 2,402.88 cases per 100,000 person-months (95% CI 1,364.62-4,231.10) in PDL with short incarceration at baseline, and 419.66 cases per 100,000 person-months (95% CI 225.80-779.95) in individuals with long incarceration at baseline (who were enrolled for the follow after at least 1 year of incarceration). The TB incidence rate among PDL with lower respiratory symptoms was 146.53 cases/100,000 person-months, and among PDL without respiratory symptoms screened for LTBI the incidence rate was 19.49 cases/100,000 person-months. History of Bacillus Calmette-Guerin vaccination decreased the risk of acquiring LTBI among PDL who were recently incarcerated. Female sex, smoked drugs, and current cigarette smoking were associated with an increased risk of developing active TB. This study shows that PDL have high risk for LTBI and active TB. It is important to perform LTBI testing at admission to prison, as well as regular follow-up to control TB in prisons.

Introduction: Hepatitis E virus (HEV) is an emergent virus of global importance; it is the etiological agent of sporadic cases and outbreaks of hepatitis. The epidemiology of this infection in Colombia is unknown., Objective: To determine the seropositivity for hepatitis E virus in Colombia in cases with clinical diagnosis of viral hepatitis., Materials and Methods: Serum samples from patients that were sent to the Instituto Nacional de Salud during the period 2005-2010 (group 1) and samples sent to the Laboratorio Departamental de Salud Pública de Antioquia during the 2008-2009 period were included in this study (group 2). Serum samples were analyzed by immunoassay with commercial kits., Results: From the 344 analyzed samples, 8.7% were positive for anti-HEV; the frequency of anti-HEV IgM was 1.74% (6/344) and the frequency of anti-HEV IgG was 7.5% (26/344). A difference in frequency of anti-HEV between group 1 (6.3%) and group 2 (1.3%) was observed. The cases were identified in nine departments of Colombia., Conclusions: This is the first study of hepatitis E virus infection in patients with diagnosis of hepatitis in Colombia. The frequency of anti-HEV described in this population of patients in Colombia is similar to that described in other Latin American countries like Brazil, Perú and Uruguay. Considering the results of this study, it could be necessary to include hepatitis E virus infection serological markers in the differential diagnosis of viral hepatitis in Colombia.

Objective: Estimate the cost-effectiveness ratio of the directly observed treatment short course (DOTS) for treatment of tuberculosis (TB), comparing it to a variation of this treatment that includes increased home-based guardian monitoring of patients (DOTS-R)., Methods: Taking a social perspective that includes the costs for the health institutions, the patients, and their family members, and for other entities that contribute to making operation of the program effective, the costs incurred with each of the two strategies were evaluated and the cost-effectiveness ratios were estimated adopting the measures of effect used by the control programs. The estimate of the cost of each of the two strategies includes the cost to the health institutions that administer treatment, the patients and their family members, and the cost to the Ministry of Health that manages public health programs on the municipal level. Based on these costs and the number of cases cured and treatments completed as outcome measures of each of the strategies evaluated, the cost-effectiveness ratio and incremental cost were calculated., Results: The DOTS-R was found to be more cost-effective for achievement of successful treatments than the DOTS. The DOTS-R recorded costs of US$ 1 122.40 to US$ 1 152.70 for each case cured compared to values of US$ 1 137.00 to US$ 1 494.30 for the DOTS. The percentage of cases treated successfully was higher with DOTS-R than with DOTS., Conclusions: The DOTS-R is a promising cost-effective alternative for improved control of TB in endemic areas. It is recommended that the health authorities include home-based guardian monitoring of patients in their institutional management of the TB program, with the participation of health workers and the physical and financial resources that currently support this program.

Introduction: Although the transfusion of blood products is a common therapy, it carries risk of transmission of infections, especially hepatitus B virus (HBV) and human immunodeficiency virus (HIV)., Objective: As part of the blood safety initiative, the Pan American Health Organization supported studies to estimate the prevalence of human immunodeficiency virus and hepatitis B virus infection in Colombia., Materials and Methods: Between February and September 2003, a cross sectional study examined 500 multiply-transfused patients at four hospital centers in the cities of Bogota and Medellin. The serum samples were analyzed by enzyme immunoassay (EIA) using commercial kits., Results: The seroprevalence of HIV infection was 1.8% (CI 95% 0.5-3.1). The seroprevalence of HBV infection was 18.6% (CI 95% 15.1-22.1). Six risk factors were associated with HIV and HBV infection: (1) receiving more than 48 units of blood or blood components, (2) diagnosis of hemophilia, (3) receiving transfusions for more than one year, (4) receiving whole blood, (5) coinfection with hepatitis C virus and (6) receiving transfusions before 1993., Conclusions: This is the first epidemiological study with a significant sample size performed in multiply-transfused patients in Colombia. The principal finding was the high prevalence of HBV and HIV infection in patients with diagnosis of hemophilia compared with the other five groups of multiply-transfused patients.

Introduction: In spite of implementation of cytology-based cervical cancer screening in Colombia, mortality rates remain stable. The description of factors associated to cervical pre-neoplasic lesions is needed to establish strategies for mortality prevention., Objective: The prevalence of epithelial squamous cell abnormalities was determined to explore the association of cytology abnormalities with described risk factors., Materials and Methods: This population-based, cross-sectional study included 739 women randomly selected by age. A validated face-to-face questionnaire and conventional cervical cytology were used to collect the information. To establish the association between cervical abnormalities and some qualitative variables, the independent chi squared test was used. We also calculated prevalence ratio with their 95% confidence intervals. A logistic regression model was used to explore variables that potentially explain cytology abnormalities., Results: The prevalence of squamous cell abnormality was 15.8%. Among women with abnormal cytology, 10% presented atypical squamous cells of undetermined significance, 3.9% low grade squamous intra-epithelial lesion and 1.9% high grade squamous intra-epithelial lesion. The adjusted logistical regression analysis showed that history of sexual transmitted disease, two or more sexual partners during entire life and previous abnormal cytology were associated with cytology abnormalities., Conclusion: The relation of epithelial squamous cell abnormalities with sexual behavior history reflexes the link between human papiloma virus infection and cervical cancer pre-neoplasic lesions. The frequency of use and knowledge about the purpose of cytology were factors that suggested other diagnostic limitations such as quality of cervical cytology or barriers to access health care. These latter factors may be the underlying basis for the high cervical cancer mortality rates.

Introduction: Prophylaxis against tuberculosis has been recognized as important for preventing clinical forms of tuberculosis, mainly in HIV positive patients. However, in countries with high tuberculosis prevalence, prophylaxis application and effectiveness remains controversial., Objective: Effectiveness was established for two prophylaxis regimens -isoniazid treatment for nine months and pirazinamid/rifampin for 60 days., Materials and Methods: Two cohort groups of patients diagnosed with HIV/AIDS were compared. One consisted of 131 volunteer patients, who received one of the two prophylactic regimens -pirazinamid/rifampin or isoniazid. The tuberculosis treatment drugs were self-administered and independent of tuberculin response tests. The second group consisted of 200 patients selected from the records of a HIV/AIDS control program. Follow up for both groups was conducted over a two-year period through clinical records., Results: The 2 groups were similar with respect to clinical and demographic variables. A higher proportion of patients in the control group had CD4 counts <200/ml and viral load >100,000 copies. In the prophylactic group, 8% of patients reported adverse effects due to the drug, and one person had tuberculosis in that group (0.8%). Ten persons in the control group contracted tuberculosis (5%) RR=0.15, 95%CI 0.02-1.18, p=0.07. The prophylaxis protective level was calculated to be 80%, after taking into account CD4, viral load, and effective antiretroviral therapy., Conclusion: The prophylaxis against tuberculosis was effective in HIV positive patients, independently of the immune status, viral load, and highly effective antiretroviral therapy.

An interview tool, Diagnostic Interview for Genetic Studies (DIGS 3.0), was translated into Spanish for application in studies of psychiatric disorders in Colombia. Two Spanish translations of the original English version of DIGS were prepared and back-translated into English. A review committee verified the linguistic and cultural equivalence of the translations. The evaluator and test-retest reliability were assessed calculating Cohen's kappa for samples of 65 and 91 patients respectively. DIGS proved valid in both appearance and content. The confidence interval (C.I.) was excellent for schizophrenia (kappa = 0.81, C.I. 95% = 0.68-0.93), bipolar disorder (kappa = 0.87, C.I. 95% = 0.75-0.99), major depressive disorder (kappa = 0.86, C.I. 95% = 0.70-1.00), and for a normal diagnosis (kappa = 0.65, C.I. 95% = 0.41-0.89); it was good for other psychiatric diagnosis (kappa = 0.65, C.I. 95% = 0.41-0.89) and poor for schizoaffective disorder (kappa = 0.37, C.I. 95% = -0.02-0.76). Test-retest reliability was excellent for all diagnoses (kappa > 0.8), except for "other psychiatric diagnoses" (kappa = 0.64, C.I. 95% = 0.31-0.96). The Spanish translation of the DIGS was comprehensible, with face and content validity, and good test-retest and evaluator reliability. This translation will be a useful tool for genetic studies of psychiatric disorders in Latin America, particularly where schizophrenia and affective disorders are involved.