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Sheila K. West - One of the best experts on this subject based on the ideXlab platform.
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children as messengers of health knowledge impact of health promotion and water infrastructure in schools on facial cleanliness and Trachoma in the community
PLOS Neglected Tropical Diseases, 2021Co-Authors: Xinyi Chen, Meraf Wolle, Harran Mkocha, Beatriz Munoz, Sheila K. WestAbstract:Background Health promotion is essential to the SAFE strategy for Trachoma elimination. Schools are a valuable venue for health promotion. However, there is little literature about the impact of health education and water infrastructure in schools on facial cleanliness and Trachoma in the community. Our study aimed to describe the current state of school health promotion in Kongwa, Tanzania, and to examine the transferability of health messages from schools to the community at large. Methodology/Findings A cross-sectional survey was carried out in all 92 villages in Kongwa district, which included 85 primary schools. Data were collected on health messages and water infrastructure in the schools. A random sample of 3084 children aged 0–5 were examined for facial cleanliness in all villages. In 50 villages, a random sample of 50 children aged 1–9 per village were examined for follicular Trachoma (TF). Thirty-seven (44.6%) schools had educational materials on face-washing. Fifty (60.2%) schools had a washing station. The presence of a health teacher was correlated with having posters on face washing in classrooms. The presence of face-washing materials was correlated with the availability of washing stations. Neither teachers mentioning face-washing in health curricula nor educational materials in classrooms were associated with clean faces or Trachoma in the community. Having a washing station in the school was associated with lower community rates of Trachoma. Conclusions Primary school health messages and materials on Trachoma were not associated with clean faces or lower rates of Trachoma in the community. The target audience for primary school health promotion is likely the students themselves, without immediate rippling effects in the community. A long-term perspective should be considered during the implementation of health promotion in schools. The goal of school health promotion should be training the next generation of parents and community health leaders in combatting Trachoma.
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Risk factors for the progression of Trachomatous scarring in a cohort of women in a Trachoma low endemic district in Tanzania
'Public Library of Science (PLoS)', 2021Co-Authors: Meraf Wolle, Harran Mkocha, Beatriz E. Muñoz, Fahd Naufal, Michael Saheb Kashaf, Sheila K. WestAbstract:Background Trachoma, a chronic conjunctivitis caused by Chlamydia Trachomatis, is the leading infectious cause of blindness worldwide. Trachoma has been targeted for elimination as a public health problem which includes reducing Trachomatous inflammation—follicular prevalence in children and reducing Trachomatous trichiasis prevalence in adults. The rate of development of Trachomatous trichiasis, the potentially blinding late-stage Trachoma sequelae, depends on the rate of Trachomatous scarring development and progression. Few studies to date have evaluated the progression of Trachomatous scarring in communities that have recently transitioned to a low Trachomatous inflammation—follicular prevalence. Methodology/Principal findings Women aged 15 and older were randomly selected from households in 48 communities within Kongwa district, Tanzania and followed over 3.5 years for this longitudinal study. Trachomatous inflammation—follicular prevalence was 5% at baseline and at follow-up in children aged 1–9 in Kongwa, Tanzania. 1018 women aged 15 and older had Trachomatous scarring at baseline and were at risk for Trachomatous scarring progression; 691 (68%) completed follow-up assessments. Photographs of the upper tarsal conjunctiva were obtained at baseline and follow-up and graded for Trachomatous scarring using a previously published four-step severity scale. The overall cumulative 3.5-year progression rate of scarring was 35.3% (95% CI 31.6–39.1). The odds of TS progression increased with an increase in age in women younger than 50, (OR 1.03, 95% CI 1.01–1.05, p = 0.005) as well as an increase in the household poverty index (OR 1.29, 95% CI 1.13–1.48, p = 0.0002). Conclusions/Significance The 3.5-year progression of scarring among women in Kongwa, a formerly hyperendemic now turned hypoendemic district in central Tanzania, was high despite a low active Trachoma prevalence. This suggests that the drivers of scarring progression are likely not related to on-going Trachoma transmission in this district. Author summary Trachoma, a chronic conjunctivitis caused by Chlamydia Trachomatis, presents with follicles (Trachomatous inflammation—follicular, TF) in children which leads to Trachomatous conjunctival scarring (TS) in young adults. TS can progress to the in-turning of eyelashes, Trachomatous trichiasis (TT) which places individuals at high risk of irreversible vision loss. Few studies to date have evaluated the progression of TS in communities that have recently transitioned to a low Trachoma prevalence. We studied the progression of TS in women in Kongwa, Tanzania a district that recently transitioned to a low prevalence of Trachoma. We found that the overall cumulative progression of scarring was 35.3% over 3.5 years. The scarring progression rate observed is very similar to what we observed a decade prior in Kongwa when the Trachoma prevalence was very high. Our findings suggest that once scarring has developed it continues to progress irrespective of the current Trachoma environment. This has potential ramifications for Trachoma elimination efforts. An area could achieve the elimination of TF and still have to deal with scarring progression, which may lead to the development of TT. If this occurs: 1) elimination of TT will be delayed which will delay the overall elimination of Trachoma as a public health problem, and 2) the limited resources available to elimination programs may need to be re-allocated
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Environmental factors and hygiene behaviors associated with facial cleanliness and Trachoma in Kongwa, Tanzania
'Public Library of Science (PLoS)', 2021Co-Authors: Xinyi Chen, Harran Mkocha, Meraf Wolle, Beatriz Munoz, Fahd Naufal, Geordie Woods, Michelle Odonkor, Sheila K. WestAbstract:Background Having a clean face is protective against Trachoma. In the past, long distances to water were associated with unclean faces and increased Trachoma. Other environmental factors have not been extensively explored. We need improved clarity on the environmental factors associated with facial cleanliness and Trachoma prevalence, especially when the disease burden is low. Methodology/Principle findings A cross-sectional survey focusing on household environments was conducted in all 92 villages in Kongwa, Tanzania, in a random selection of 1798 households. Children aged 0–5 years in these households were examined for facial cleanliness. In each of the 50 randomly-selected villages, 50 children aged 1–9 years were randomly selected and examined for Trachoma. In a multivariate model adjusting for child age, we found that children were more likely to have clean faces if the house had a clean yard (OR 1.62, 95% CI 1.37–1.91), an improved latrine (OR 1.11, 95% CI 1.01–1.22), and greater water storage capacity (OR 1.02, 95% CI 1.00–1.04), and if there were clothes washed and drying around the house (OR 1.30, 95% CI 1.09–1.54). However, measures of crowding, wealth, time spent on obtaining water, or the availability of piped water was not associated with clean faces. Using a cleanliness index (clean yard, improved latrine, washing clothes, ≥1 child in the household having a clean face), the community prevalence of Trachoma decreased with an increase in the average value of the index (OR 2.28, 95% CI 1.17–4.80). Conclusions/Significance Access to water is no longer a significant limiting factor in children’s facial cleanliness in Kongwa. Instead, water storage capacity and the way that water is utilized are more important in facial cleanliness. A household cleanliness index with a holistic measure of household environment is associated with reduced community prevalence of Trachoma. Author summary Trachoma, a leading cause of blindness, is caused by repeated infection that is spread from person to person via contaminated ocular and nasal discharge. Having a clean face is protective against Trachoma. In the past, long distances to water were associated with unclean faces. Other environmental elements have not been extensively explored. We need improved clarity on the environmental factors affecting facial cleanliness and Trachoma prevalence, especially when the disease burden is low but still above 5%. We conducted a household survey in every village in Kongwa district, Tanzania, and found that access to water has significantly improved and is no longer a limiting factor in children’s facial cleanliness. When households have more storage capacity for water used for washing, wash their clothes frequently and clean their yards, young children in the households are more likely to have clean faces. We then created a household cleanliness index that comprises a clean yard, washed clothes, an improved latrine and at least one child in the household having a clean face. We found that an increased average index score in the community is associated with a decreased prevalence of Trachoma, suggesting that a multi-pronged approach to improve household cleanliness is valuable
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surveillance and azithromycin treatment for newcomers and travelers evaluation asante trial design and baseline characteristics
Ophthalmic Epidemiology, 2016Co-Authors: Annmargret Ervin, Thomas C. Quinn, Harran Mkocha, Beatriz Munoz, Laura Dize, Charlotte A Gaydos, Kurt Dreger, Sheila K. WestAbstract:Purpose: Immigrants and travelers may be sources of re-emergent infection in Trachoma-endemic communities close to Trachoma elimination. The primary objective of the A Surveillance and Azithromycin...
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can we use antibodies to chlamydia Trachomatis as a surveillance tool for national Trachoma control programs results from a district survey
PLOS Neglected Tropical Diseases, 2016Co-Authors: Sheila K. West, Thomas C. Quinn, Beatriz Munoz, Laura Dize, Charlotte A Gaydos, Jerusha Weaver, Zakayo Mrango, Diana L. MartinAbstract:Background Trachoma is targeted for elimination by 2020. World Health Organization advises districts to undertake surveillance when follicular Trachoma (TF) <5% in children 1–9 years and mass antibiotic administration has ceased. There is a question if other tools could be used for surveillance as well. We report data from a test for antibodies to C. Trachomatis antigen pgp3 as a possible tool. Methodology We randomly sampled 30 hamlets in Kilosa district, Tanzania, and randomly selected 50 children ages 1–9 per hamlet. The tarsal conjunctivae were graded for Trachoma (TF), tested for C. Trachomatis infection (Aptima Combo2 assay: Hologic, San Diego, CA), and a dried blood spot processed for antibodies to C. Trachomatis pgp3 using a multiplex bead assay on a Luminex 100 platform. Principal findings The prevalence of Trachoma (TF) was 0.4%, well below the <5% indicator for re-starting a program. Infection was also low, 1.1%. Of the 30 hamlets, 22 had neither infection nor TF. Antibody positivity overall was low, 7.5% and increased with age from 5.2% in 1–3 year olds, to 9.3% in 7–9 year olds (p = 0.015). In 16 of the 30 hamlets, no children ages 1–3 years had antibodies to pgp3. Conclusions The antibody status of the 1–3 year olds indicates low cumulative exposure to infection during the surveillance period. Four years post MDA, there is no evidence for re-emergence of follicular Trachoma.
Martin J Holland - One of the best experts on this subject based on the ideXlab platform.
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the link between ocular infection with non chlamydial bacteria and Trachomatous eye changes
Access Microbiology, 2020Co-Authors: Tamsyn Derrick, Matthew J Burton, Patrick Massae, Abigail Walkerjacobs, Athumani M Ramadhani, Elias Mafuru, Aiweda Malisa, Tara Mtuy, Martin J HollandAbstract:Introduction Globally, C. Trachomatis is the leading infectious cause of blindness. There is evidence to suggest that Trachomatous inflammation may be linked to ocular infection with other pathogenic organisms. Methods Conjunctival swab samples from 472 Tanzanian children who participated in a 4-year longitudinal study were analysed using optimised duplex qPCR assays to assess carriage of H. influenzae, CNS, S. pneumoniae and Adenovirus spp. in each sample. The presence of C. Trachomatis (Ct) in the conjunctiva had previously been recorded. Logistic regression analysis, adjusted for age and sex, was performed to identify associations between the prevalence of bacterial infection and (1) progressive scarring Trachoma, and (2) active Trachoma (defined as the presence of follicular Trachoma (TF) or Trachomatous inflammation (TI)). Results Logistic regression identified no significant associations between (1) progressive scarring Trachoma and Ct;and (2) progressive scarring Trachoma and non-chlamydial bacterial infection. Active Trachoma was only associated with conjunctival infection with H. influenzae. Logistic regression found that patients with ocular H. influenzae infection were more likely to demonstrate clinically-graded active Trachoma (TF + TI) (OR = 1.96, 95% CI: 1.11 – 3.56, p = 0.023). Individual analyses of TF or TI and their associations with H. influenzae found (1) a strong association between ocular H. influenzae infection and TF (OR = 2.21, p = 0.0095); (2) no association between ocular H. influenzae infection and TI (OR = 2.19, p = 0.19). Conclusion These results indicate that H. influenzae might contribute to the TF phenotype. TF is widely used to assess population levels of Trachoma.
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Active Trachoma Cases in the Solomon Islands Have Varied Polymicrobial Community Structures but Do Not Associate with Individual Non-Chlamydial Pathogens of the Eye
Frontiers Media S.A., 2018Co-Authors: Robert M. R. Butcher, Martin J Holland, Oliver Sokana, Kelvin Jack, Eric Kalae, Leslie Sui, Charles Russell, Joanna Houghton, Christine Palmer, Richard Le T. MesurierAbstract:BackgroundSeveral non-chlamydial microbial pathogens are associated with clinical signs of active Trachoma in Trachoma-endemic communities with a low prevalence of ocular Chlamydia Trachomatis (Ct) infection. In the Solomon Islands, the prevalence of Ct among children is low despite the prevalence of active Trachoma being moderate. Therefore, we set out to investigate whether active Trachoma was associated with a common non-chlamydial infection or with a dominant polymicrobial community dysbiosis in the Solomon Islands.MethodsWe studied DNA from conjunctival swabs collected from 257 Solomon Islanders with active Trachoma and matched controls. Droplet digital PCR was used to test for pathogens suspected to be able to induce follicular conjunctivitis. Polymicrobial community diversity and composition were studied by sequencing of hypervariable regions of the 16S ribosomal ribonucleic acid gene in a subset of 54 cases and 53 controls.ResultsAlthough Ct was associated with active Trachoma, the number of infections was low (cases, 3.9%; controls, 0.4%). Estimated prevalence (cases and controls, respectively) of each non-chlamydial infection was as follows: Staphylococcus aureus: 1.9 and 1.9%, Adenoviridae: 1.2 and 1.2%, coagulase-negative Staphylococcus: 5.8 and 4.3%, Haemophilus influenzae: 7.4 and 11.7%, Moraxella catarrhalis: 2.3 and 4.7%, and Streptococcus pneumoniae: 7.0 and 6.2%. There was no statistically significant association between the clinical signs of Trachoma and the presence or load of any of the non-Ct infections that were assayed. Interindividual variations in the conjunctival microbiome were characterized by differences in the levels of Corynebacterium, Propionibacterium, Helicobacter, and Paracoccus, but diversity and relative abundance of these specific genera did not differ significantly between cases and controls.DiscussionIt is unlikely that the prevalent Trachoma-like follicular conjunctivitis in this region of the Solomon Islands has a dominant bacterial etiology. Before implementing community-wide azithromycin distribution for Trachoma, policy makers should consider that clinical signs of Trachoma can be observed in the absence of any detectable azithromycin-susceptible organism
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inverse relationship between microrna 155 and 184 expression with increasing conjunctival inflammation during ocular chlamydia Trachomatis infection
BMC Infectious Diseases, 2015Co-Authors: Tamsyn Derrick, Sarah E Burr, Chrissy H Roberts, Meno Nabicassa, Eunice Cassama, Robin L Bailey, David Mabey, Matthew J Burton, Martin J HollandAbstract:Background Trachoma, a preventable blinding eye disease, is initiated by ocular infection with Chlamydia Trachomatis (Ct). We previously showed that microRNAs (miR) -147b and miR-1285 were up-regulated in inflammatory Trachomatous scarring. During the initial stage of disease, follicular Trachoma with current Ct infection, the differential expression of miR has not yet been investigated.
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serology for Trachoma surveillance after cessation of mass drug administration
PLOS Neglected Tropical Diseases, 2015Co-Authors: Diana L. Martin, Rhiannon Bid, Frank Sandi, Brook E Goodhew, Patrick Massae, Augustin Lasway, Heiko Philippin, William Makupa, Sandra Molina, Martin J HollandAbstract:Background Trachoma, caused by Chlamydia Trachomatis (Ct), is the leading infectious cause of blindness worldwide. Yearly azithromycin mass drug administration (MDA) plays a central role in efforts to eliminate blinding Trachoma as a public health problem. Programmatic decisionmaking is currently based on the prevalence of the clinical sign “Trachomatous inflammation-follicular” (TF) in children. We sought to test alternative tools for Trachoma surveillance based on serology in the 12-year cohort of Kahe Mpya, Rombo District, Tanzania, where ocular chlamydial infection was eliminated with azithromycin MDA by 2005.
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the conjunctival microbiome in health and Trachomatous disease a case control study
Genome Medicine, 2014Co-Authors: Chrissy H Roberts, Robin L Bailey, David Mabey, Matthew J Burton, Martin J Holland, Hassan Joof, Pateh Makalo, Yanjiao Zhou, George M WeinstockAbstract:Background Trachoma, caused by Chlamydia Trachomatis, remains the worlds leading infectious cause of blindness. Repeated ocular infection during childhood leads to scarring of the conjunctiva, in-turning of the eyelashes (trichiasis) and corneal opacity in later life. There is a growing body of evidence to suggest non-chlamydial bacteria are associated with clinical signs of Trachoma, independent of C. Trachomatis infection.
Robin L Bailey - One of the best experts on this subject based on the ideXlab platform.
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inverse relationship between microrna 155 and 184 expression with increasing conjunctival inflammation during ocular chlamydia Trachomatis infection
BMC Infectious Diseases, 2015Co-Authors: Tamsyn Derrick, Sarah E Burr, Chrissy H Roberts, Meno Nabicassa, Eunice Cassama, Robin L Bailey, David Mabey, Matthew J Burton, Martin J HollandAbstract:Background Trachoma, a preventable blinding eye disease, is initiated by ocular infection with Chlamydia Trachomatis (Ct). We previously showed that microRNAs (miR) -147b and miR-1285 were up-regulated in inflammatory Trachomatous scarring. During the initial stage of disease, follicular Trachoma with current Ct infection, the differential expression of miR has not yet been investigated.
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the conjunctival microbiome in health and Trachomatous disease a case control study
Genome Medicine, 2014Co-Authors: Chrissy H Roberts, Robin L Bailey, David Mabey, Matthew J Burton, Martin J Holland, Hassan Joof, Pateh Makalo, Yanjiao Zhou, George M WeinstockAbstract:Background Trachoma, caused by Chlamydia Trachomatis, remains the worlds leading infectious cause of blindness. Repeated ocular infection during childhood leads to scarring of the conjunctiva, in-turning of the eyelashes (trichiasis) and corneal opacity in later life. There is a growing body of evidence to suggest non-chlamydial bacteria are associated with clinical signs of Trachoma, independent of C. Trachomatis infection.
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risk factors for active Trachoma and ocular chlamydia Trachomatis infection in treatment naive Trachoma hyperendemic communities of the bijagos archipelago guinea bissau
PLOS Neglected Tropical Diseases, 2014Co-Authors: Sarah E Burr, Meno Nabicassa, Eunice Cassama, David Mabey, Martin J Holland, Helen A Weiss, Emma M Hardingesch, Robin L BaileyAbstract:Background Trachoma, caused by ocular infection with Chlamydia Trachomatis, is hyperendemic on the Bijagos Archipelago of Guinea Bissau. An understanding of the risk factors associated with active Trachoma and infection on these remote and isolated islands, which are atypical of Trachoma-endemic environments described elsewhere, is crucial to the implementation of Trachoma elimination strategies. Methodology/Principal Findings A cross-sectional population-based Trachoma prevalence survey was conducted on four islands. We conducted a questionnaire-based risk factor survey, examined participants for Trachoma using the World Health Organization (WHO) simplified grading system and collected conjunctival swab samples for 1507 participants from 293 randomly selected households. DNA extracted from conjunctival swabs was tested using the Roche Amplicor CT/NG PCR assay. The prevalence of active (follicular and/or inflammatory) Trachoma was 11% (167/1508) overall and 22% (136/618) in 1–9 year olds. The prevalence of C. Trachomatis infection was 18% overall and 25% in 1–9 year olds. There were strong independent associations of active Trachoma with ocular and nasal discharge, C. Trachomatis infection, young age, male gender and type of household water source. C. Trachomatis infection was independently associated with young age, ocular discharge, type of household water source and the presence of flies around a latrine. Conclusions/Significance In this remote island environment, household-level risk factors relating to fly populations, hygiene behaviours and water usage are likely to be important in the transmission of ocular C. Trachomatis infection and the prevalence of active Trachoma. This may be important in the implementation of environmental measures in Trachoma control.
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follicular Trachoma and trichiasis prevalence in an urban community in the gambia west africa is there a need to include urban areas in national Trachoma surveillance
Tropical Medicine & International Health, 2013Co-Authors: E Quicke, Sarah E Burr, Robin L Bailey, Emma M Hardingesch, Ansumana Sillah, Hassan Joof, Pateh MakaloAbstract:objectives Urban areas are traditionally excluded from Trachoma surveillance activities, but due to rapid expansion and population growth, the urban area of Brikama in The Gambia may be developing social problems that are known risk factors for Trachoma. It is also a destination for many migrants who may be introducing active Trachoma into the area. This study aimed to determine the prevalence and risk factors for follicular Trachoma and trichiasis in Brikama. methods A community-based cross-sectional prevalence survey including 27 randomly selected households in 12 randomly selected enumeration areas (EAs) of Brikama. Selected households were offered eye examinations, and the severity of Trachoma was graded according to WHO’s simplified grading system. Risk factor data were collected from each household via a questionnaire. results The overall prevalence of Trachomatous inflammation‐follicular (TF) in children aged 1‐9 years was 3.8% (95% CI 2.5‐5.6), and the overall prevalence of trichiasis in adults aged ! 15 years was 0.46% (95% CI 0.17‐1.14). EA prevalence of TF varied from 0% to 8.4%. The major risk factors for TF were dirty faces (P 5%, it may be prudent to include Brikama in surveillance programmes. Trichiasis remains a public health problem (>0.1%), and active case finding needs to be undertaken.
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application of smartphone cameras for detecting clinically active Trachoma
British Journal of Ophthalmology, 2012Co-Authors: Satasuk Joy Bhosai, Jeremy D Keenan, Robin L Bailey, Abdou Amza, Nassirou Beido, Bruce D Gaynor, Thomas M LietmanAbstract:The WHO is committed to eliminating Trachoma as a public health concern by 2020.1 Since decisions for mass treatment are determined by the prevalence of clinical Trachoma in a community, efficient and accurate methods for monitoring clinical activity remain a priority.2 However, reliability of clinical examination is poor and disagreement between graders is common.3 Photography of the conjunctiva could reduce variability and improve accuracy of Trachoma surveillance. Currently, research studies use single-lens reflex (SLR) cameras to validate field grading.4 Yet, SLR cameras are expensive and require substantial field training to operate, and thus few Trachoma programmes have adopted this technology. A simpler, more affordable camera may increase uptake of this diagnostic technique. In view of growing applications of mobile technology,5 we examined the use of smartphone imaging in Trachoma. During a recent programme, Partnership for the Rapid Elimination of Trachoma (PRET study) visit in Niger, we performed …
Paul M Emerson - One of the best experts on this subject based on the ideXlab platform.
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antimicrobial resistance following mass azithromycin distribution for Trachoma a systematic review
Lancet Infectious Diseases, 2019Co-Authors: Kieran S Obrien, Paul M Emerson, Pamela J Hooper, Arthur L Reingold, Elena G Dennis, Jeremy D Keenan, Thomas M Lietman, Catherine E OldenburgAbstract:Summary Mass azithromycin distribution is a core component of Trachoma control programmes and could reduce mortality in children younger than 5 years in some settings. In this systematic review we synthesise evidence on the emergence of antimicrobial resistance after mass azithromycin distribution. We searched electronic databases for publications up to June 14, 2018. We included studies of any type (excluding modelling studies, surveillance reports, and review articles) on community-wide distribution of oral azithromycin for the prevention and treatment of Trachoma that assessed macrolide resistance, without restrictions to the type of organism. We extracted prevalence of resistance from published reports and requested unpublished data from authors of included studies. Of 213 identified studies, 19 met inclusion criteria (12 assessed Streptococcus pneumoniae) and were used for qualitative synthesis. Macrolide resistance after azithromycin distribution was reported in three of the five organisms studied. The lack of resistance in Chlamydia Trachomatis suggests that azithromycin might remain effective for Trachoma programmes, but evidence is scarce. As mass azithromycin distribution for Trachoma continues and is considered for other indications, ongoing monitoring of antimicrobial resistance will be required.
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the geographical distribution and burden of Trachoma in africa
PLOS Neglected Tropical Diseases, 2013Co-Authors: Jennifer L Smith, Paul M Emerson, Pamela J Hooper, David Mabey, Anthony W Solomon, Rebecca M Flueckiger, Sarah Polack, Elizabeth A Cromwell, Stephanie L Palmer, Danny HaddadAbstract:Background There remains a lack of epidemiological data on the geographical distribution of Trachoma to support global mapping and scale up of interventions for the elimination of Trachoma. The Global Atlas of Trachoma (GAT) was launched in 2011 to address these needs and provide standardised, updated and accessible maps. This paper uses data included in the GAT to describe the geographical distribution and burden of Trachoma in Africa. Methods Data assembly used structured searches of published and unpublished literature to identify cross-sectional epidemiological data on the burden of Trachoma since 1980. Survey data were abstracted into a standardised database and mapped using geographical information systems (GIS) software. The characteristics of all surveys were summarized by country according to data source, time period, and survey methodology. Estimates of the current population at risk were calculated for each country and stratified by endemicity class. Results At the time of writing, 1342 records are included in the database representing surveys conducted between 1985 and 2012. These data were provided by direct contact with national control programmes and academic researchers (67%), peer-reviewed publications (17%) and unpublished reports or theses (16%). Prevalence data on active Trachoma are available in 29 of the 33 countries in Africa classified as endemic for Trachoma, and 1095 (20.6%) districts have representative data collected through population-based prevalence surveys. The highest prevalence of active Trachoma and trichiasis remains in the Sahel area of West Africa and Savannah areas of East and Central Africa and an estimated 129.4 million people live in areas of Africa confirmed to be Trachoma endemic. Conclusion The Global Atlas of Trachoma provides the most contemporary and comprehensive summary of the burden of Trachoma within Africa. The GAT highlights where future mapping is required and provides an important planning tool for scale-up and surveillance of Trachoma control.
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incremental cost of conducting population based prevalence surveys for a neglected tropical disease the example of Trachoma in 8 national programs
PLOS Neglected Tropical Diseases, 2011Co-Authors: Chaoqun Chen, Elizabeth A Cromwell, Emma M Hardingesch, Jeremiah Ngondi, Jonathan D King, Aryc W Mosher, Paul M EmersonAbstract:BACKGROUND Trachoma prevalence surveys provide the evidence base for district and community-wide implementation of the SAFE strategy, and are used to evaluate the impact of Trachoma control interventions. An economic analysis was performed to estimate the cost of Trachoma prevalence surveys conducted between 2006 and 2010 from 8 national Trachoma control programs in Africa. METHODOLOGY AND FINDINGS Data were collected retrospectively from reports for 165 districts surveyed for Trachoma prevalence using a cluster random sampling methodology in Ethiopia, Ghana, Mali, Niger, Nigeria, Sudan, Southern Sudan and The Gambia. The median cost per district survey was $4,784 (inter-quartile range [IQR]?=?$3,508-$6,650) while the median cost per cluster was $311 (IQR?=?$119-$393). Analysis by cost categories (personnel, transportation, supplies and other) and cost activity (training, field work, supervision and data entry) revealed that the main cost drivers were personnel and transportation during field work. CONCLUSION Population-based cluster random surveys are used to provide the evidence base to set objectives and determine when elimination targets have been reached for several neglected tropical diseases, including Trachoma. The cost of conducting epidemiologically rigorous prevalence surveys should not be a barrier to program implementation or evaluation.
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estimation of effects of community intervention with antibiotics facial cleanliness and environmental improvement a f e in five districts of ethiopia hyperendemic for Trachoma
British Journal of Ophthalmology, 2010Co-Authors: Jeremiah Ngondi, Elizabeth A Cromwell, Teshome Gebre, Estifanos B Shargie, Liknaw Adamu, Tesfaye Teferi, Mulat Zerihun, Berhan Ayele, Jonathan D King, Paul M EmersonAbstract:Aims The WHO recommends the SAFE (surgery, antibiotics, facial cleanliness and environmental improvement) strategy for Trachoma control. We aimed to investigate the association between active Trachoma and community intervention with antibiotics, facial cleanliness, environmental improvement (A,F,E) components of SAFE in five Trachoma hyperendemic districts of Amhara region, Ethiopia. Methods Cluster random surveys were undertaken to evaluate SAFE following 3 years of interventions. Children aged 1–9 years were examined for Trachoma signs using the WHO simplified grading system and structured questionnaires used to assess uptake of A, F and E. Active Trachoma signs (Trachomatous inflammation-follicular (TF) and Trachomatous inflammation-intense (TI)) were used to derive an ordinal severity score where TI was considered more severe than TF. Associations between active Trachoma and potential factors were investigated using ordinal logistic multilevel regression models. Results A total of 1813 children aged 1–9 years were included in the analysis. Factors independently associated with reduced odds of active Trachoma signs were: number of times treated with azithromycin (p-trend=0.026); months since last mass azithromycin distribution (p-trend Conclusion These findings are important, since they make the case for continued implementing the A,F,E interventions simultaneously, and suggest appropriate timing of SAFE evaluations within 6–12 months after the last mass azithromycin distribution.
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associations between active Trachoma and community intervention with antibiotics facial cleanliness and environmental improvement a f e
PLOS Neglected Tropical Diseases, 2008Co-Authors: Jeremiah Ngondi, Fiona E Matthews, Mark Reacher, Samson Baba, Carol Brayne, Paul M EmersonAbstract:Background Surgery, Antibiotics, Facial cleanliness and Environmental improvement (SAFE) are advocated by the World Health Organization (WHO) for Trachoma control. However, few studies have evaluated the complete SAFE strategy, and of these, none have investigated the associations of Antibiotics, Facial cleanliness, and Environmental improvement (A,F,E) interventions and active Trachoma. We aimed to investigate associations between active Trachoma and A,F,E interventions in communities in Southern Sudan. Methods and Findings Surveys were undertaken in four districts after 3 years of implementation of the SAFE strategy. Children aged 1–9 years were examined for Trachoma and uptake of SAFE assessed through interviews and observations. Using ordinal logistic regression, associations between signs of active Trachoma and A,F,E interventions were explored. Trachomatous inflammation-intense (TI) was considered more severe than Trachomatous inflammation-follicular (TF). A total of 1,712 children from 25 clusters (villages) were included in the analysis. Overall uptake of A,F,E interventions was: 53.0% of the eligible children had received at least one treatment with azithromycin; 62.4% children had a clean face on examination; 72.5% households reported washing faces of children two or more times a day; 73.1% households had received health education; 44.4% of households had water accessible within 30 minutes; and 6.3% households had pit latrines. Adjusting for age, sex, and district baseline prevalence of active Trachoma, factors independently associated with reduced odds of a more severe active Trachoma sign were: receiving three treatments with azithromycin (odds ratio [OR] = 0.1; 95% confidence interval [CI] 0.0–0.4); clean face (OR = 0.3; 95% CI 0.2–0.4); washing faces of children three or more times daily (OR = 0.4; 95% CI 0.3–0.7); and presence and use of a pit latrine in the household (OR = 0.4; 95% CI 0.2–0.9). Conclusion Analysis of associations between the A,F,E components of the SAFE strategy and active Trachoma showed independent protective effects against active Trachoma of mass systemic azithromycin treatment, facial cleanliness, face washing, and use of pit latrines in the household. This strongly argues for continued use of all the components of the SAFE strategy together.
David Mabey - One of the best experts on this subject based on the ideXlab platform.
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low prevalence of ocular chlamydia Trachomatis infection and active Trachoma in the western division of fiji
PLOS Neglected Tropical Diseases, 2016Co-Authors: Colin K Macleod, David Mabey, Rebecca Willis, Neal Alexander, Robert Butcher, Umesh Mudaliar, Kinisimere Natutusau, Alexandre L Pavluck, Luisa Cikamatana, Mike KamaAbstract:BACKGROUND: Trachoma is the leading infectious cause of blindness and is caused by ocular infection with the bacterium Chlamydia Trachomatis (Ct). While the majority of the global disease burden is found in sub-Saharan Africa, the Western Pacific Region has been identified as Trachoma endemic. Population surveys carried out throughout Fiji have shown an abundance of both clinically active Trachoma and Trachomatous trichiasis in all divisions. This finding is at odds with the clinical experience of local healthcare workers who do not consider Trachoma to be highly prevalent. We aimed to determine whether conjunctival infection with Ct could be detected in one administrative division of Fiji. METHODS: A population-based survey of 2306 individuals was conducted using the Global Trachoma Mapping Project methodology. Population prevalence of active Trachoma in children and trichiasis in adults was estimated using the World Health Organization simplified grading system. Conjunctival swabs were collected from 1009 children aged 1-9 years. DNA from swabs was tested for the presence of the Ct plasmid and human endogenous control. RESULTS: The prevalence of active Trachoma in 1-9 year olds was 3.4%. The age-adjusted prevalence was 2.8% (95% CI: 1.4-4.3%). The unadjusted prevalence of ocular Ct infection in 1-9 year-olds was 1.9% (19/1009), and the age-adjusted infection prevalence was 2.3% (95% CI: 0.4-2.5%). The median DNA load was 41 Ct plasmid copies per swab (min 20, first quartile 32, mean 6665, third quartile 161, max 86354). There was no association between current infection and follicular Trachoma. No cases of Trachomatous trichiasis were identified. DISCUSSION: The Western Division of Fiji has a low prevalence of clinical Trachoma. Ocular Ct infections were observed, but they were predominantly low load infections and were not correlated with clinical signs. Our study data suggest that Trachoma does not meet the WHO definition of a public health problem in this Division of Fiji, but the inconsistency with previous studies warrants further investigation.
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inverse relationship between microrna 155 and 184 expression with increasing conjunctival inflammation during ocular chlamydia Trachomatis infection
BMC Infectious Diseases, 2015Co-Authors: Tamsyn Derrick, Sarah E Burr, Chrissy H Roberts, Meno Nabicassa, Eunice Cassama, Robin L Bailey, David Mabey, Matthew J Burton, Martin J HollandAbstract:Background Trachoma, a preventable blinding eye disease, is initiated by ocular infection with Chlamydia Trachomatis (Ct). We previously showed that microRNAs (miR) -147b and miR-1285 were up-regulated in inflammatory Trachomatous scarring. During the initial stage of disease, follicular Trachoma with current Ct infection, the differential expression of miR has not yet been investigated.
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the conjunctival microbiome in health and Trachomatous disease a case control study
Genome Medicine, 2014Co-Authors: Chrissy H Roberts, Robin L Bailey, David Mabey, Matthew J Burton, Martin J Holland, Hassan Joof, Pateh Makalo, Yanjiao Zhou, George M WeinstockAbstract:Background Trachoma, caused by Chlamydia Trachomatis, remains the worlds leading infectious cause of blindness. Repeated ocular infection during childhood leads to scarring of the conjunctiva, in-turning of the eyelashes (trichiasis) and corneal opacity in later life. There is a growing body of evidence to suggest non-chlamydial bacteria are associated with clinical signs of Trachoma, independent of C. Trachomatis infection.
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risk factors for active Trachoma and ocular chlamydia Trachomatis infection in treatment naive Trachoma hyperendemic communities of the bijagos archipelago guinea bissau
PLOS Neglected Tropical Diseases, 2014Co-Authors: Sarah E Burr, Meno Nabicassa, Eunice Cassama, David Mabey, Martin J Holland, Helen A Weiss, Emma M Hardingesch, Robin L BaileyAbstract:Background Trachoma, caused by ocular infection with Chlamydia Trachomatis, is hyperendemic on the Bijagos Archipelago of Guinea Bissau. An understanding of the risk factors associated with active Trachoma and infection on these remote and isolated islands, which are atypical of Trachoma-endemic environments described elsewhere, is crucial to the implementation of Trachoma elimination strategies. Methodology/Principal Findings A cross-sectional population-based Trachoma prevalence survey was conducted on four islands. We conducted a questionnaire-based risk factor survey, examined participants for Trachoma using the World Health Organization (WHO) simplified grading system and collected conjunctival swab samples for 1507 participants from 293 randomly selected households. DNA extracted from conjunctival swabs was tested using the Roche Amplicor CT/NG PCR assay. The prevalence of active (follicular and/or inflammatory) Trachoma was 11% (167/1508) overall and 22% (136/618) in 1–9 year olds. The prevalence of C. Trachomatis infection was 18% overall and 25% in 1–9 year olds. There were strong independent associations of active Trachoma with ocular and nasal discharge, C. Trachomatis infection, young age, male gender and type of household water source. C. Trachomatis infection was independently associated with young age, ocular discharge, type of household water source and the presence of flies around a latrine. Conclusions/Significance In this remote island environment, household-level risk factors relating to fly populations, hygiene behaviours and water usage are likely to be important in the transmission of ocular C. Trachomatis infection and the prevalence of active Trachoma. This may be important in the implementation of environmental measures in Trachoma control.
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the geographical distribution and burden of Trachoma in africa
PLOS Neglected Tropical Diseases, 2013Co-Authors: Jennifer L Smith, Paul M Emerson, Pamela J Hooper, David Mabey, Anthony W Solomon, Rebecca M Flueckiger, Sarah Polack, Elizabeth A Cromwell, Stephanie L Palmer, Danny HaddadAbstract:Background There remains a lack of epidemiological data on the geographical distribution of Trachoma to support global mapping and scale up of interventions for the elimination of Trachoma. The Global Atlas of Trachoma (GAT) was launched in 2011 to address these needs and provide standardised, updated and accessible maps. This paper uses data included in the GAT to describe the geographical distribution and burden of Trachoma in Africa. Methods Data assembly used structured searches of published and unpublished literature to identify cross-sectional epidemiological data on the burden of Trachoma since 1980. Survey data were abstracted into a standardised database and mapped using geographical information systems (GIS) software. The characteristics of all surveys were summarized by country according to data source, time period, and survey methodology. Estimates of the current population at risk were calculated for each country and stratified by endemicity class. Results At the time of writing, 1342 records are included in the database representing surveys conducted between 1985 and 2012. These data were provided by direct contact with national control programmes and academic researchers (67%), peer-reviewed publications (17%) and unpublished reports or theses (16%). Prevalence data on active Trachoma are available in 29 of the 33 countries in Africa classified as endemic for Trachoma, and 1095 (20.6%) districts have representative data collected through population-based prevalence surveys. The highest prevalence of active Trachoma and trichiasis remains in the Sahel area of West Africa and Savannah areas of East and Central Africa and an estimated 129.4 million people live in areas of Africa confirmed to be Trachoma endemic. Conclusion The Global Atlas of Trachoma provides the most contemporary and comprehensive summary of the burden of Trachoma within Africa. The GAT highlights where future mapping is required and provides an important planning tool for scale-up and surveillance of Trachoma control.
