BackgroundThe only available vaccine that could be potentially beneficial against mycobacterial diseases contains live attenuated bovine tuberculosis bacillus (Mycobacterium bovis) also called Bacillus Calmette-Guérin (BCG). Even though the BCG vaccine is still widely used, results on its effectiveness in preventing mycobacterial diseases are partially contradictory, especially regarding Buruli Ulcer Disease (BUD). The aim of this case-control study is to evaluate the possible protective effect of BCG vaccination on BUD.MethodologyThe present study was performed in three different countries and sites where BUD is endemic: in the Democratic Republic of the Congo, Ghana, and Togo from 2010 through 2013. The large study population was comprised of 401 cases with laboratory confirmed BUD and 826 controls, mostly family members or neighbors.Principal FindingsAfter stratification by the three countries, two sexes and four age groups, no significant correlation was found between the presence of BCG scar and BUD status of individuals. Multivariate analysis has shown that the independent variables country (p = 0.31), sex (p = 0.24), age (p = 0.96), and presence of a BCG scar (p = 0.07) did not significantly influence the development of BUD category I or category II/III. Furthermore, the status of BCG vaccination was also not significantly related to duration of BUD or time to healing of lesions.ConclusionsIn our study, we did not observe significant evidence of a protective effect of routine BCG vaccination on the risk of developing either BUD or severe forms of BUD. Since accurate data on BCG strains used in these three countries were not available, no final conclusion can be drawn on the effectiveness of BCG strain in protecting against BUD. As has been suggested for tuberculosis and leprosy, well-designed prospective studies on different existing BCG vaccine strains are needed also for BUD.

BackgroundSince the early 1990s more than 1,800 patients with lesions suspicious for Buruli ulcer disease (BUD) have been reported from Togo. However, less than five percent of these were laboratory confirmed. Since 2007, the Togolese National Buruli Ulcer Control Program has been supported by the German Leprosy and Tuberculosis Relief Association (DAHW). Collaboration with the Department for Infectious Diseases and Tropical Medicine (DITM), University Hospital, Munich, Germany, allowed IS2404 PCR analysis of diagnostic samples from patients with suspected BUD during a study period of three years.Methodology/Principal FindingsThe DAHW integrated active BUD case finding in the existing network of TB/Leprosy Controllers and organized regular training and outreach activities to identify BUD cases at community level. Clinically suspected cases were referred to health facilities for diagnosis and treatment. Microscopy was carried out locally, external quality assurance (EQA) at DITM. Diagnostic samples from 202 patients with suspected BUD were shipped to DITM, 109 BUD patients (54%) were confirmed by PCR, 43 (29.9%) by microscopy. All patients originated from Maritime Region. EQA for microscopy resulted in 62% concordant results.Conclusions/SignificanceThis study presents a retrospective analysis of the first cohort of clinically suspected BUD cases from Togo subjected to systematic laboratory analysis over a period of three years and confirms the prevalence of BUD in Maritime Region. Intensified training in the field of case finding and sample collection increased the PCR case confirmation rate from initially less than 50% to 70%. With a PCR case confirmation rate of 54% for the entire study period the WHO standards (case confirmation rate ≥50%) have been met. EQA for microscopy suggests the need for intensified supervision and training. In January 2011 the National Hygiene Institute, Lomé, has assumed the role of a National Reference Laboratory for PCR confirmation and microscopy.

BackgroundIn a previous study PCR analysis of clinical samples from suspected cases of Buruli ulcer disease (BUD) from Togo and external quality assurance (EQA) for local microscopy were conducted at an external reference laboratory in Germany. The relatively poor performance of local microscopy as well as effort and time associated with shipment of PCR samples necessitated the implementation of stringent EQA measures and availability of local laboratory capacity. This study describes the approach to implementation of a national BUD reference laboratory in Togo.MethodologyLarge scale outreach activities accompanied by regular training programs for health care professionals were conducted in the regions “Maritime” and “Central,” standard operating procedures defined all processes in participating laboratories (regional, national and external reference laboratories) as well as the interaction between laboratories and partners in the field. Microscopy was conducted at regional level and slides were subjected to EQA at national and external reference laboratories. For PCR analysis, sample pairs were collected and subjected to a dry-reagent-based IS2404-PCR (DRB-PCR) at national level and standard IS2404 PCR followed by IS2404 qPCR analysis of negative samples at the external reference laboratory.Principal FindingsThe inter-laboratory concordance rates for microscopy ranged from 89% to 94%; overall, microscopy confirmed 50% of all suspected BUD cases. The inter-laboratory concordance rate for PCR was 96% with an overall PCR case confirmation rate of 78%. Compared to a previous study, the rate of BUD patients with non-ulcerative lesions increased from 37% to 50%, the mean duration of disease before clinical diagnosis decreased significantly from 182.6 to 82.1 days among patients with ulcerative lesions, and the percentage of category III lesions decreased from 30.3% to 19.2%.ConclusionsHigh inter-laboratory concordance rates as well as case confirmation rates of 50% (microscopy), 71% (PCR at national level), and 78% (including qPCR confirmation at external reference laboratory) suggest high standards of BUD diagnostics. The increase of non-ulcerative lesions, as well as the decrease in diagnostic delay and category III lesions, prove the effect of comprehensive EQA and training measures involving also procedures outside the laboratory.

BackgroundAs the major burden of Buruli ulcer disease (BUD) occurs in remote rural areas, development of point-of-care (POC) tests is considered a research priority to bring diagnostic services closer to the patients. Loop-mediated isothermal amplification (LAMP), a simple, robust and cost-effective technology, has been selected as a promising POC test candidate. Three BUD-specific LAMP assays are available to date, but various technical challenges still hamper decentralized application. To overcome the requirement of cold-chains for transport and storage of reagents, the aim of this study was to establish a dry-reagent-based LAMP assay (DRB-LAMP) employing lyophilized reagents.Methodology/Principal FindingsFollowing the design of an IS2404 based conventional LAMP (cLAMP) assay suitable to apply lyophilized reagents, a lyophylization protocol for the DRB-LAMP format was developed. Clinical performance of cLAMP was validated through testing of 140 clinical samples from 91 suspected BUD cases by routine assays, i.e. IS2404 dry-reagent-based (DRB) PCR, conventional IS2404 PCR (cPCR), IS2404 qPCR, compared to cLAMP. Whereas qPCR rendered an additional 10% of confirmed cases and samples respectively, case confirmation and positivity rates of DRB-PCR or cPCR (64.84% and 56.43%; 100% concordant results in both assays) and cLAMP (62.64% and 52.86%) were comparable and there was no significant difference between the sensitivity of the assays (DRB PCR and cPCR, 86.76%; cLAMP, 83.82%). Likewise, sensitivity of cLAMP (95.83%) and DRB-LAMP (91.67%) were comparable as determined on a set of 24 samples tested positive in all routine assays.Conclusions/SignificanceBoth LAMP formats constitute equivalent alternatives to conventional PCR techniques. Provided the envisaged availability of field friendly DNA extraction formats, both assays are suitable for decentralized laboratory confirmation of BUD, whereby DRB-LAMP scores with the additional advantage of not requiring cold-chains. As validation of the assays was conducted in a third-level laboratory environment, field based evaluation trials are necessary to determine the clinical performance at peripheral health care level.

BackgroundThe emergence of avian influenza A/H5N1 in 2003 as well as the pandemic influenza A (H1N1) pdm09 highlighted the need to establish influenza sentinel surveillance in Togo. The Ministry of Health decided to introduce Influenza to the list of diseases with epidemic potential. By April 2010, Togo was actively involved in influenza surveillance. This study aims to describe the implementation of ILI surveillance and results obtained from April 2010 to December 2012.MethodsTwo sites were selected based on their accessibility and affordability to patients, their adequate specimen storage capacity and transportation system. Patients with ILI presenting at sentinel sites were enrolled by trained medical staff based on the World Health Organization (WHO) case definitions. Oropharyngeal and nasopharyngeal samples were collected and they were tested at the National Influenza Reference Laboratory using a U.S. Centers for Disease Control and Prevention (CDC) validated real time RT-PCR protocol. Laboratory results and epidemiological data were reported weekly and shared with all sentinel sites, Ministry of Health, Division of Epidemiology, WHO and CDC/NAMRU-3.ResultsFrom April 2010 to December 2012, a total of 955 samples were collected with 52% of the study population aged between 0 and 4 years. Of the 955 samples, 236 (24.7%) tested positive for influenza viruses; with 136 (14.2%) positive for influenza A and 100 (10.5%) positive for influenza B. The highest influenza positive percentage (30%) was observed in 5–14 years old and patients aged 0–4 and >60 years had the lowest percentage (20%). Clinical symptoms such as cough and rhinorrhea were associated more with ILI patients who were positive for influenza type A than influenza type B. Influenza viruses circulated throughout the year with the positivity rate peaking around the months of January, May and again in October; corresponding respectively to the dry-dusty harmattan season and the long and then the short raining season. The pandemic A (H1N1) pdm09 was the predominantly circulating strain in 2010 while influenza B was the predominantly circulating strain in 2011. The seasonal A/H3N2 was observed throughout 2012 year.ConclusionsThis study provides information on influenza epidemiology in the capital city of Togo.

BackgroundFollowing introduction of antimycobacterial treatment of Buruli ulcer disease (BUD), several clinical studies evaluated treatment outcomes of BUD patients, in particular healing times, secondary lesions and functional limitations. Whereas recurrences were rarely observed, paradoxical reactions and functional limitations frequently occurred. Although systematic BUD control in Togo was established as early as 2007, treatment outcome has not been reviewed to date. Therefore, a pilot project on post-treatment follow-up of BUD patients in Togo aimed to evaluate treatment outcomes and to provide recommendations for optimization of treatment success.Methodology/Principal FindingsOut of 199 laboratory confirmed BUD patients, 129 could be enrolled in the study. The lesions of 109 patients (84.5%) were completely healed without any complications, 5 patients (3.9%) had secondary lesions and 15 patients (11.6%) had functional limitations. Edema, category III ulcers >15cm, healing times >180 days and a limitation of movement at time of discharge constituted the main risk factors significantly associated with BUD related functional limitations (P<0.01). Review of all BUD related documentation revealed major shortcomings, in particular concerning medical records on adjuvant surgical and physiotherapeutic treatment.Conclusions/SignificanceThis study presents the first systematic analysis of treatment outcome of BUD patients from Togo. Median times to healing and the absence of recurrences were in line with findings reported by other investigators. The percentage of functional limitations of 11.6% was lower than in other studies, and edema, category III ulcers, healing time >180 days and limitation of movement at discharge constituted the main risk factors for functional limitations in Togolese BUD patients. Standardized treatment plans, patient assessment and follow-up, as well as improved management of medical records are recommended to allow for intensified monitoring of disease progression and healing process, to facilitate implementation of therapeutic measures and to optimize treatment success.

Abstract.During 2014, Africa reported more than half of the global suspected cholera cases. Based on the data collected from seven countries in the African Cholera Surveillance Network (Africhol), we assessed the sensitivity, specificity, and positive and negative predictive values of clinical cholera case definitions, including that recommended by the World Health Organization (WHO) using culture confirmation as the gold standard. The study was designed to assess results in real-world field situations in settings with recent cholera outbreaks or endemicity. From June 2011 to July 2015, a total of 5,084 persons with suspected cholera were tested for Vibrio cholerae in seven different countries of which 35.7% had culture confirmation. For all countries combined, the WHO case definition had a sensitivity = 92.7%, specificity = 8.1%, positive predictive value = 36.1%, and negative predictive value = 66.6%. Adding dehydration, vomiting, or rice water stools to the case definition could increase the specificity without a substantial decrease in sensitivity. Future studies could further refine our findings primarily by using more sensitive methods for cholera confirmation.

Background Leprosy continues to be a health problem in endemic areas. More than 200,000 new cases of leprosy per year suggest that transmission of the disease is still ongoing, presumably as airborne infection through nasal droplets. Late diagnosis supports continued transmission and increases the individual risk for functional disabilities. Laboratory tools are considered beneficial to facilitate early detection and clinical assessment of cases. The aim of this study was to validate molecular tools allowing detection, quantification and assessment of viability of M. leprae from nasal swab samples which are easy to obtain without the need of any invasive procedures. Methods Validation of two real-time PCRs detecting M. leprae DNA (RLEP qPCR) and RNA (16S rRNA RT qPCR) was conducted on “must not detect”/“must detect” samples and 160 pre-treatment nasal swab samples from 20 clinically diagnosed multibacillary (MB) leprosy patients from Togo. Results Both assays were 100% M. leprae specific and showed analytical sensitivities of three templates each. Out of 20 clinically diagnosed MB leprosy patients, 15 (75.0%) had a positive RLEP qPCR result from nasal swab samples. The 16S rRNA RT qPCR detected viable bacilli in nasal swab samples of ten out of these 15 RLEP positive patients (66.7%). Conclusion The combined RLEP/16S rRNA (RT) qPCR assay provides a sensitive and specific tool to determine the bacterial load and viability of M. leprae from nasal swab samples and is applicable for early diagnosis, monitoring treatment response and investigating the role of nasal carriage of M. leprae in human-to-human transmission through aerosol infection. Electronic supplementary material The online version of this article (10.1186/s12879-019-4349-9) contains supplementary material, which is available to authorized users.