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Robinson A, Versteeg B, Abdurahman OS, Clatworthy I, Shuka G, Debela D, Hordofa G, Reis de Oliveira Gomes L, Abraham Aga M, Dumessa G, Sarah V, Macleod D, Last A, Burton MJ, Logan JG. Field- and laboratory-based studies on correlates of Chlamydia trachomatis transmission by Musca sorbens: Determinants of fly-eye contact and investigations into fly carriage of elementary bodies. PLoS Negl Trop Dis 2024; 18:e0012280. [PMID: 38954734 PMCID: PMC11249242 DOI: 10.1371/journal.pntd.0012280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 07/15/2024] [Accepted: 06/07/2024] [Indexed: 07/04/2024] Open
Abstract
Musca sorbens (Diptera: Muscidae) flies are thought to be vectors of the blinding eye disease trachoma, carrying the bacterium Chlamydia trachomatis (Ct) between the eyes of individuals. While their role as vectors has been convincingly demonstrated via randomised controlled trials in The Gambia, studies of fly-borne trachoma transmission remain scant and as such our understanding of their ability to transmit Ct remains poor. We examined fly-eye contact and caught eye-seeking flies from 494 individuals (79% aged ≤9 years) in Oromia, Ethiopia. Ct-carrying flies (harbouring Ct DNA) were found to cluster spatially in and nearby to households in which at least one resident had Ct infection. Fly-eye contact was positively associated with the presence of trachoma (disease), lower human body weight and increased human body temperature. Studies of laboratory-reared M. sorbens indicated that Ct is found both externally and internally following feeds on Ct culture, with scanning electron microscopy revealing how Ct bodies can cling to fly hairs (setae). Testing for Ct on field-caught M. sorbens found fly 'bodies' (thorax, wings and abdomen) to consistently test positive for Ct while legs and heads were infrequently Ct-positive. These studies strongly support the role of M. sorbens as vectors of trachoma and highlight the need for improved understanding of fly-borne trachoma transmission dynamics and vector competence.
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Affiliation(s)
- Ailie Robinson
- Department of Disease Control, LSHTM, London, United Kingdom
| | - Bart Versteeg
- International Centre for Eye Health, Clinical Research Department, London School of Hygiene & Tropical Medicine (LSHTM), London, United Kingdom
- Knowledge Institute of the Dutch Association of Medical Specialists, Utrecht, The Netherlands
| | - Oumer Shafi Abdurahman
- International Centre for Eye Health, Clinical Research Department, London School of Hygiene & Tropical Medicine (LSHTM), London, United Kingdom
- The Fred Hollows Foundation Ethiopia, Addis Ababa, Ethiopia
| | | | - Gemeda Shuka
- The Fred Hollows Foundation Ethiopia, Addis Ababa, Ethiopia
| | - Dereje Debela
- The Fred Hollows Foundation Ethiopia, Addis Ababa, Ethiopia
| | | | | | | | | | | | - David Macleod
- International Centre for Eye Health, Clinical Research Department, London School of Hygiene & Tropical Medicine (LSHTM), London, United Kingdom
- MRC International Statistics and Epidemiology Group, LSHTM, London, United Kingdom
| | - Anna Last
- International Centre for Eye Health, Clinical Research Department, London School of Hygiene & Tropical Medicine (LSHTM), London, United Kingdom
| | - Matthew J Burton
- International Centre for Eye Health, Clinical Research Department, London School of Hygiene & Tropical Medicine (LSHTM), London, United Kingdom
- National Institute for Health Research Biomedical Research Centre for Ophthalmology at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom
| | - James G Logan
- Department of Disease Control, LSHTM, London, United Kingdom
- Arctech Innovation Ltd, Dagenham, United Kingdom
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Buralli RJ, da Silva ZP, Alencar GP, Figueiredo GM, Hoshida MS, Luna EJA, Pastro LDM, Santos OAD, Marques LJP, Zerbinati RM, Galisteo Junior AJ, Andrade Junior HD, Machado CM, Meireles LR, Schultz R, Rodrigues LC, Francisco RPV, Novaes HMD, Almeida MFD, Gouveia N. Assessing the risks for stillbirth in São Paulo, Brazil: protocol for a multidisciplinary case-control study - FetRisks. BMJ Open 2024; 14:e079261. [PMID: 38866578 PMCID: PMC11177680 DOI: 10.1136/bmjopen-2023-079261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 05/27/2024] [Indexed: 06/14/2024] Open
Abstract
Stillbirth is a fundamental component of childhood mortality, but its causes are still insufficiently understood. This study aims to explore stillbirth risk factors by using a multidisciplinary approach to stimulate public policies and protocols to prevent stillbirth, improve maternal care and support bereaved families. METHODS AND ANALYSIS: In this case-control study with stillbirths and live births in 14 public hospitals in São Paulo, mothers are interviewed at hospitals after delivery, and hospital records and prenatal care registries are reviewed. Maternal and umbilical cord blood samples and placentas are collected to analyse angiogenesis and infection biomarkers, and the placenta's anatomopathological exam. Air pollutant exposure is estimated through the participant's residence and work addresses. Traditional and non-invasive autopsies by image-guided histopathology are conducted in a subset of stillbirths. Subsample mothers of cases are interviewed at home 2 months after delivery on how they were dealing with grief. Information contained in the official prenatal care registries of cases and controls is being compiled. Hospital managers are interviewed about the care offered to stillbirth mothers. Data analysis will identify the main risk factors for stillbirth, investigate their interrelations, and evaluate health services care and support for bereaved families. We hope this project will contribute to the understanding of stillbirth's risk factors and related health services in Brazil, providing new knowledge about this central public health problem, contributing to the improvement of public policies and prenatal and puerperal care, helping to prevent stillbirths and improve the healthcare and support for bereaved families. ETHICS AND DISSEMINATION: This study protocol was approved by the Ethics Committee of the Municipal Health Secretary (process no 16509319.0.3012.5551) and of the Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo (process no 16509319.0.0000.0068). Results will be communicated to the study participants, policy-makers and the scientific community.
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Affiliation(s)
- Rafael Junqueira Buralli
- Departamento de Medicina Preventiva, Universidade de Sao Paulo Faculdade de Medicina, Sao Paulo, Brazil
| | - Zilda Pereira da Silva
- Departamento de Epidemiologia, Universidade de Sao Paulo Faculdade de Saude Publica, São Paulo, Brazil
| | - Gizelton Pereira Alencar
- Departamento de Epidemiologia, Universidade de Sao Paulo Faculdade de Saude Publica, São Paulo, Brazil
| | - Gerusa Maria Figueiredo
- Universidade de São Paulo Instituto de Medicina Tropical de São Paulo, Sao Paulo, Brazil
- Departamento de Medicina Preventiva, Universidade de São Paulo Faculdade de Medicina, São Paulo, Brazil
| | - Mara Sandra Hoshida
- Laboratorio de Investigaçao Medica em Fisiologia Obstetrica (LIM 57), Universidade de São Paulo Hospital das Clínicas, São Paulo, Brazil
| | - Expedito J A Luna
- Departamento de Medicina Preventiva, Universidade de São Paulo Faculdade de Medicina, São Paulo, Brazil
- Universidade de São Paulo Instituto de Medicina Tropical de São Paulo, São Paulo, Brazil
| | | | - Osmara Alves Dos Santos
- Departamento de Medicina Preventiva, Universidade de São Paulo Faculdade de Medicina, São Paulo, Brazil
| | | | - Rodrigo Melim Zerbinati
- Laboratorio de Virologia (LIM 52), Universidade de São Paulo Instituto de Medicina Tropical de São Paulo, São Paulo, Brazil
| | - Andrés Jimenez Galisteo Junior
- Laboratorio de Investigaçao Medica em Protozoologia, Bacteriologia e Resistencia Antimicrobiana (LIM 49), Universidade de Sao Paulo Hospital das Clinicas, São Paulo, Brazil
| | - Heitor de Andrade Junior
- Universidade de São Paulo Instituto de Medicina Tropical de São Paulo, São Paulo, Brazil
- Laboratorio de Anatomia Patologica, Universidade de Sao Paulo Hospital das Clinicas, São Paulo, Brazil
| | - Clarisse M Machado
- Universidade de São Paulo Instituto de Medicina Tropical de São Paulo, São Paulo, Brazil
- Laboratorio de Virologia (LIM 52), Universidade de São Paulo Instituto de Medicina Tropical de São Paulo, São Paulo, Brazil
| | | | - Regina Schultz
- Laboratorio de Anatomia Patologica, Universidade de Sao Paulo Hospital das Clinicas, São Paulo, Brazil
| | | | - Rossana Pulcineli Vieira Francisco
- Laboratorio de Investigaçao Medica em Fisiologia Obstetrica (LIM 57), Universidade de São Paulo Hospital das Clínicas, São Paulo, Brazil
- Departamento de Obstetricia e Ginecologia, Universidade de Sao Paulo Faculdade de Medicina, São Paulo, Brazil
| | | | - Marcia Furquim de Almeida
- Departamento de Epidemiologia, Universidade de Sao Paulo Faculdade de Saude Publica, São Paulo, Brazil
| | - Nelson Gouveia
- Departamento de Medicina Preventiva, Universidade de Sao Paulo Faculdade de Medicina, Sao Paulo, Brazil
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Favacho JDFR, Leite KK, Jacomasso T, Farias AB, Franco Filho LC, Gomes STM, dos Reis HS, Mota GD, Schluga PHDC, Tassi WS, Rampazzo RDCP, West SK, Gaydos CA, da Cunha AJLA, Costa ADT. Validation of a New Duplex Real-Time Polymerase Chain Reaction for Chlamydia trachomatis DNA Detection in Ocular Swab Samples. Diagnostics (Basel) 2024; 14:892. [PMID: 38732307 PMCID: PMC11083659 DOI: 10.3390/diagnostics14090892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 03/21/2024] [Accepted: 03/26/2024] [Indexed: 05/13/2024] Open
Abstract
Trachoma is the world-leading infectious cause of preventable blindness and is caused by the bacteria Chlamydia trachomatis. In developing countries, diagnosis is usually based on clinical evaluation. Serological-based tests are cheaper than molecular-based ones, but the latter are more sensitive and specific. The present study developed a new duplex qPCR which concomitantly detects the C. trachomatis cryptic plasmid and the human 18S rRNA gene, with an LOD95% for C. trachomatis DNA of 13.04 genome equivalents per reaction. The new qPCR was tested using 50 samples from an endemic area and 12 from a non-endemic area that were previously characterized using direct immunofluorescence assay (DFA) and clinical evaluation. Among the 50 endemic samples, 3 were found to be positive by clinical evaluation (6%), 18 were found to be positive by DFA (36%), and 48 were found to be positive by qPCR (96%). Next, the new duplex qPCR was validated using 50 samples previously characterized by qPCR. Validation was carried out on a benchtop instrument (ABI7500) or on a portable point-of-care instrument (Q3-Plus), showing 95% specificity and 100% sensitivity. The ubiquitous presence of C. trachomatis DNA in samples from the endemic region confirms that constant monitoring is of paramount importance for the effective measurement of the elimination of trachoma. The newly developed duplex qPCR presented in this study, along with its validation in a portable qPCR system, constitutes important tools toward achieving this goal.
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Affiliation(s)
- Joana da Felicidade Ribeiro Favacho
- Evandro Chagas Institute, Secretariat of Health and Environment Surveillance, Ministry of Health (IEC/SVSA/MS), Ananindeua 67030-000, PA, Brazil; (L.C.F.F.); (H.S.d.R.)
| | - Keren Kariene Leite
- Institute of Molecular Biology of Paraná (IBMP), Curitiba 81350-010, PR, Brazil (T.J.)
| | - Thiago Jacomasso
- Institute of Molecular Biology of Paraná (IBMP), Curitiba 81350-010, PR, Brazil (T.J.)
| | - Aline Burda Farias
- Institute of Molecular Biology of Paraná (IBMP), Curitiba 81350-010, PR, Brazil (T.J.)
| | - Luciano Chaves Franco Filho
- Evandro Chagas Institute, Secretariat of Health and Environment Surveillance, Ministry of Health (IEC/SVSA/MS), Ananindeua 67030-000, PA, Brazil; (L.C.F.F.); (H.S.d.R.)
| | - Samara Tatielle Monteiro Gomes
- Evandro Chagas Institute, Secretariat of Health and Environment Surveillance, Ministry of Health (IEC/SVSA/MS), Ananindeua 67030-000, PA, Brazil; (L.C.F.F.); (H.S.d.R.)
| | - Herald Souza dos Reis
- Evandro Chagas Institute, Secretariat of Health and Environment Surveillance, Ministry of Health (IEC/SVSA/MS), Ananindeua 67030-000, PA, Brazil; (L.C.F.F.); (H.S.d.R.)
| | - Gardene Dourado Mota
- Evandro Chagas Institute, Secretariat of Health and Environment Surveillance, Ministry of Health (IEC/SVSA/MS), Ananindeua 67030-000, PA, Brazil; (L.C.F.F.); (H.S.d.R.)
| | | | - Walleyd Sami Tassi
- Institute of Molecular Biology of Paraná (IBMP), Curitiba 81350-010, PR, Brazil (T.J.)
| | | | - Sheila Kay West
- Dana Center for Preventative Ophthalmology, Johns Hopkins University, Baltimore, MD 21287, USA;
| | - Charlotte Ann Gaydos
- International Sexually Transmitted Disease Research Laboratory, Division of Infectious Diseases, Johns Hopkins University, Baltimore, MD 21218, USA
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Shafi Abdurahman O, Last A, Macleod D, Habtamu E, Versteeg B, Dumessa G, Guye M, Nure R, Adugna D, Miecha H, Greenland K, Burton MJ. Trachoma risk factors in Oromia Region, Ethiopia. PLoS Negl Trop Dis 2023; 17:e0011679. [PMID: 37934731 PMCID: PMC10629622 DOI: 10.1371/journal.pntd.0011679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 09/21/2023] [Indexed: 11/09/2023] Open
Abstract
BACKGROUND Trachoma, the leading infectious cause of blindness, is caused by the bacterium Chlamydia trachomatis (Ct). Despite enormous disease control efforts and encouraging progress, trachoma remains a significant public health problem in 44 countries. Ethiopia has the greatest burden of trachoma worldwide, however, robust data exploring transmission risk factors and the association between socio-economic status is lacking from some regions. This is the first study to investigate these factors in this South-Eastern region of Oromia, Ethiopia. METHODOLOGY/PRINCIPAL FINDINGS A total of 1211 individuals were enrolled from 247 households in Shashemene Rural district in Oromia Region between 11th April and 25th June 2018, of whom 628 (51.9%) were female and 526 (43.4%) were children aged 1-9 years. Three standardised ophthalmic nurses examined each participant for the presence of active trachoma using the WHO simplified trachoma grading system. Conjunctival swab samples were collected from the upper tarsal conjunctiva of the left eye of each participant. Ct was detected using quantitative PCR. Risk factor data were collected through structured interviews and direct observations. Clinical signs of trachomatous inflammation-follicular among children aged 1-9 (TF1-9) were observed in at least one eye of 106/526 (20.2%) and trachomatous inflammation-intense among children aged 1-9 (TI1-9) were observed in at least one eye of 10/526 (1.9%). We detected Ct by PCR in 23 individuals, of whom 18 (78.3%) were in children aged 1-9 years. Among the 106 children aged 1-9 years with TF, 12 (11.3%) were Ct PCR positive and among 20 children aged 1-9 years with TI, 4 (20.0%) were Ct PCR positive. In a multivariable model, adjusting for household clustering, active trachoma was associated with younger age, the poorest households (aOR = 2.56, 95% CI 1.21-5.51), presence of flies on the face (aOR = 2.87, 95% CI 1.69-6.46), and ocular discharge (aOR = 1.89, 95% CI 1.03-3.24). Pre-school children face washing more than once a day had lower odds of having active trachoma (aOR = 0.59, 95% CI 0.19-0.84). The same was true for washing children's clothing at least once per week (aOR = 0.27, 95% CI 0.33-1.02). CONCLUSION/SIGNIFICANCE Younger age, personal hygiene in this age group (presence of ocular and nasal discharges, infrequent washing of faces and clothing) and fly-eye contacts are potential risk factors for trachoma in this setting, suggesting that hygiene interventions and environmental improvements are required to suppress transmission to ensure sustained reduction in disease burden Further studies are needed to evaluate these interventions for trachoma control and elimination. Trachoma remains a disease associated with lower socio-economic status, emphasising the need for continued implementation of control measures in addition to poverty reduction interventions in this region.
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Affiliation(s)
- Oumer Shafi Abdurahman
- International Centre for Eye Health, Clinical Research Department, Faculty of Infectious and Tropical diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- The Fred Hollows Foundation, Addis Ababa, Ethiopia
| | - Anna Last
- International Centre for Eye Health, Clinical Research Department, Faculty of Infectious and Tropical diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - David Macleod
- International Centre for Eye Health, Clinical Research Department, Faculty of Infectious and Tropical diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Esmael Habtamu
- International Centre for Eye Health, Clinical Research Department, Faculty of Infectious and Tropical diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Bart Versteeg
- International Centre for Eye Health, Clinical Research Department, Faculty of Infectious and Tropical diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | - Meseret Guye
- The Fred Hollows Foundation, Addis Ababa, Ethiopia
| | - Rufia Nure
- The Fred Hollows Foundation, Addis Ababa, Ethiopia
| | - Dereje Adugna
- Oromia Regional Health Bureau, Addis Ababa, Ethiopia
| | - Hirpha Miecha
- Oromia Regional Health Bureau, Addis Ababa, Ethiopia
| | - Katie Greenland
- Environmental Health Group, Department for Disease Control, Faculty of Infectious and Tropical. Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Matthew J. Burton
- International Centre for Eye Health, Clinical Research Department, Faculty of Infectious and Tropical diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- National Institute for Health Research Biomedical Research Centre for Ophthalmology at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom
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Barton A, Faal N, Ramadhani A, Derrick T, Mafuru E, Mtuy T, Massae P, Malissa A, Joof H, Makalo P, Sillah A, Harte A, Pickering H, Bailey R, Mabey DCW, Burton MJ, Holland MJ. Longitudinal changes in tear cytokines and antimicrobial proteins in trachomatous disease. PLoS Negl Trop Dis 2023; 17:e0011689. [PMID: 37862368 PMCID: PMC10619880 DOI: 10.1371/journal.pntd.0011689] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 11/01/2023] [Accepted: 09/28/2023] [Indexed: 10/22/2023] Open
Abstract
BACKGROUND Trachoma is a neglected tropical disease caused by ocular infection with Chlamydia trachomatis, where repeated infections and chronic inflammation can ultimately result in scarring, trichiasis and blindness. While scarring is thought to be mediated by a dysregulated immune response, the kinetics of cytokines and antimicrobial proteins in the tear film have not yet been characterised. METHODOLOGY Pooled tears from a Gambian cohort and Tanzanian cohort were semi-quantitatively screened using a Proteome Profiler Array to identify cytokines differentially regulated in disease. Based on this screen and previous literature, ten cytokines (CXCL1, IP-10, IFN-γ, IL-1β, IL-8, IL-10, IL-12 p40, IL-1RA, IL-1α and PDGF), lysozyme and lactoferrin were assayed in the Tanzanian cohort by multiplex cytokine assay and ELISA. Finally, CXCL1, IP-10, IL-8, lysozyme and lactoferrin were longitudinally profiled in the Gambian cohort by multiplex cytokine assay and ELISA. RESULTS In the Tanzanian cohort, IL-8 was significantly increased in those with clinically inapparent infection (p = 0.0086). Lysozyme, IL-10 and chemokines CXCL1 and IL-8 were increased in scarring (p = 0.016, 0.046, 0.016, and 0.037). CXCL1, IP-10, IL-8, lysozyme and lactoferrin were longitudinally profiled over the course of infection in a Gambian cohort study, with evidence of an inflammatory response both before, during and after detectable infection. CXCL1, IL-8 and IP-10 were higher in the second infection episode relative to the first (p = 0.0012, 0.044, and 0.04). CONCLUSIONS These findings suggest that the ocular immune system responds prior to and continues to respond after detectable C. trachomatis infection, possibly due to a positive feedback loop inducing immune activation. Levels of CXC chemokines in successive infection episodes were increased, which may offer an explanation as to why repeated infections are a risk factor for scarring.
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Affiliation(s)
- Amber Barton
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
| | - Nkoyo Faal
- Medical Research Council Gambia at LSHTM, Atlantic Boulevard, Fajara, Banjul, The Gambia
| | - Athumani Ramadhani
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
- Department of Ophthalmology, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Tamsyn Derrick
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
| | - Elias Mafuru
- Department of Ophthalmology, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Tara Mtuy
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
- Department of Ophthalmology, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Patrick Massae
- Department of Ophthalmology, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Aiweda Malissa
- Department of Ophthalmology, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Hassan Joof
- Medical Research Council Gambia at LSHTM, Atlantic Boulevard, Fajara, Banjul, The Gambia
| | - Pateh Makalo
- Medical Research Council Gambia at LSHTM, Atlantic Boulevard, Fajara, Banjul, The Gambia
| | - Ansumana Sillah
- National Eye Health Programme, Ministry of Health, Banjul, The Gambia
| | - Anna Harte
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
| | - Harry Pickering
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
| | - Robin Bailey
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
| | - David CW Mabey
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
| | - Matthew J. Burton
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
| | - Martin J. Holland
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
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Derrick T, Habtamu E, Tadesse Z, Callahan EK, Worku A, Gashaw B, Macleod D, Mabey DC, Holland MJ, Burton MJ. The conjunctival transcriptome in Ethiopians after trichiasis surgery: associations with the development of eyelid contour abnormalities and the effect of oral doxycycline treatment. Wellcome Open Res 2022; 4:130. [PMID: 37426632 PMCID: PMC10323279 DOI: 10.12688/wellcomeopenres.15419.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2022] [Indexed: 07/31/2023] Open
Abstract
Background: Surgery to correct trichiasis is a key component of the World Health Organisation trachoma control strategy, however unfavourable outcomes such as eyelid contour abnormalities (ECA) following surgery are relatively common. This study aimed to understand the transcriptional changes associated with the early development of ECA and the impact of doxycycline, which has anti-inflammatory and anti-fibrotic properties, upon these transcription patterns. Methods: One thousand Ethiopians undergoing trichiasis surgery were enrolled in a randomised controlled trial following informed consent. Equal groups of randomly assigned individuals were orally administered with 100mg/day of doxycycline (n=499) or placebo (n=501) for 28 days. Conjunctival swabs were collected immediately prior to surgery and at one- and six-months post-surgery. 3' mRNA sequencing was performed on paired baseline and one-month samples from 48 individuals; 12 in each treatment/outcome group (Placebo-Good outcome, Placebo-Poor outcome, Doxycycline-Good outcome, Doxycycline-Poor outcome). qPCR validation was then performed for 46 genes of interest in 145 individuals who developed ECA at one month and 145 matched controls, using samples from baseline, one and six months. Results: All treatment/outcome groups upregulated genes associated with wound healing pathways at one month relative to baseline, however no individual differences were detected between groups. The summed expression of a highly coexpressed cluster of pro-fibrotic genes was higher in patients that developed ECA in the placebo group relative to controls. qPCR validation revealed that all genes in this cluster and a number of other pro-inflammatory genes were strongly associated with ECA, however these associations were not modulated by trial arm. Conclusions: The development of post-operative ECA is associated with overexpression of pro-inflammatory and pro-fibrotic genes including growth factors, matrix metalloproteinases, collagens and extracellular matrix proteins. There was no evidence that doxycycline modulated the association between gene expression and ECA.
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Affiliation(s)
- Tamsyn Derrick
- London School of Hygiene and Tropical Medicine, London, UK
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Esmael Habtamu
- London School of Hygiene and Tropical Medicine, London, UK
- The Carter Center, Addis Ababa, Ethiopia
| | | | | | - Abebaw Worku
- Amhara Regional Health Bureau, Bahirdar, Ethiopia
| | | | - David Macleod
- London School of Hygiene and Tropical Medicine, London, UK
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Ghasemian E, Inic-Kanada A, Collingro A, Mejdoubi L, Alchalabi H, Keše D, Elshafie BE, Hammou J, Barisani-Asenbauer T. Comparison of genovars and Chlamydia trachomatis infection loads in ocular samples from children in two distinct cohorts in Sudan and Morocco. PLoS Negl Trop Dis 2021; 15:e0009655. [PMID: 34370735 PMCID: PMC8376198 DOI: 10.1371/journal.pntd.0009655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 08/19/2021] [Accepted: 07/16/2021] [Indexed: 11/30/2022] Open
Abstract
Trachoma is a blinding disease caused by repeated conjunctival infection with different Chlamydia trachomatis (Ct) genovars. Ct B genovars have been associated with more severe trachoma symptoms. Here, we investigated associations between Ct genovars and bacterial loads in ocular samples from two distinct geographical locations in Africa, which are currently unclear. We tested ocular swabs from 77 Moroccan children (28 with trachomatous inflammation-follicular (TF) and 49 healthy controls), and 96 Sudanese children (54 with TF and 42 healthy controls) with a Ct-specific real-time polymerase chain reaction (PCR) assay. To estimate bacterial loads, Ct-positive samples were further processed by multiplex real-time qPCR to amplify the chromosomal outer membrane complex B and plasmid open reading frame 2 of Ct. Genotyping was performed by PCR-based amplification of the outer membrane protein A gene (~1120 base pairs) of Ct and Sanger sequencing. Ct-positivities among the Moroccan and Sudanese patient groups were 60·7% and 31·5%, respectively. Significantly more Sudanese patients than Moroccan patients were genovar A-positive. In contrast, B genovars were significantly more prevalent in Moroccan patients than in Sudanese patients. Significantly higher Ct loads were found in samples positive for B genovars (598596) than A genovar (51005). Geographical differences contributed to the distributions of different ocular Ct genovars. B genovars may induce a higher bacterial load than A genovars in trachoma patients. Our findings emphasize the importance of conducting broader studies to elucidate if the noted difference in multiplication abilities are genovar and/or endemicity level dependent. We investigated the association between different Ct genovars, the approximate load of infection, and the distribution of Chlamydia genovars by comparing samples from one trachoma-endemic area (i.e., the city of El-Gadaref in Al Qadarif, Sudan) and one previously endemic area (i.e., the Zagora Province in Morocco), currently considered as non-endemic. This study is the first to reveal a significant difference between the genome copy numbers of Ct genovar A and B/Ba in children with TF. Evidence that Ct is still circulating in rural foci of countries like Morocco that are no longer considered endemic implies that the continuation of the trachoma surveillance must be warranted in future to avoid further spreading of Ct. The clinical significance of different infectious loads in the development of sequelae has to be determined as well as whether these differences are genovar specific or related to the given endemicity level.
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Affiliation(s)
- Ehsan Ghasemian
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Aleksandra Inic-Kanada
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Astrid Collingro
- Centre for Microbiology and Environmental Systems Science, Division of Microbial Ecology, University of Vienna, Vienna, Austria
| | - Lamiss Mejdoubi
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Hadeel Alchalabi
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Darja Keše
- Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | | | - Jaouad Hammou
- Medicine and Pharmacy Faculty, Mohammed V University, Rabat, Morocco
| | - Talin Barisani-Asenbauer
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
- * E-mail:
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Derrick TR, Sandetskaya N, Pickering H, Kölsch A, Ramadhani A, Mafuru E, Massae P, Malisa A, Mtuy T, Burton MJ, Holland MJ, Kuhlmeier D. DjinniChip: evaluation of a novel molecular rapid diagnostic device for the detection of Chlamydia trachomatis in trachoma-endemic areas. Parasit Vectors 2020; 13:533. [PMID: 33109267 PMCID: PMC7590679 DOI: 10.1186/s13071-020-04414-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 10/21/2020] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The clinical signs of active trachoma are often present in the absence of ocular Chlamydia trachomatis infection, particularly following mass drug administration. Treatment decisions following impact surveys and in post-control surveillance for communities are currently based on the prevalence of clinical signs, which may result in further unnecessary distribution of mass antibiotic treatment and the increased spread of macrolide resistance alleles in 'off-target' bacterial species. We therefore developed a simple, fast, low cost diagnostic assay (DjinniChip) for diagnosis of ocular C. trachomatis for use by trachoma control programmes. METHODS The study was conducted in the UK, Germany and Tanzania. For clinical testing in Tanzania, specimens from a sample of 350 children between the ages of 7 to 15 years, which were part of a longitudinal cohort that began in February 2012 were selected. Two ocular swabs were taken from the right eye. The second swab was collected dry, kept cool in the field and archived at - 80 °C before sample lysis for DjinniChip detection and parallel nucleic acid purification and detection/quantification by qPCR assay. RESULTS DjinniChip was able to reliably detect > 10 copies of C. trachomatis per test and correctly identified 7/10 Quality Control for Molecular Diagnostics C. trachomatis panel samples, failing to detect 3 positive samples with genome equivalent amounts ≤ 10 copies. DjinniChip performed well across a range of typical trachoma field conditions and when used by lay personnel using a series of mock samples. In the laboratory in Tanzania, using clinical samples the sensitivity and specificity of DjinniChip for C. trachomatis was 66% (95% CI 51-78) and 94.8 (95% CI 91-97%) with an overall accuracy of 90.1 (95% CI 86.4-93). CONCLUSIONS DjinniChip performance is extremely promising, particularly its ability to detect low concentrations of C. trachomatis and its usability in field conditions. The DjinniChip requires further development to reduce inhibition and advance toward a closed system. DjinniChip results did not vary between local laboratory results and typical trachoma field settings, illustrating its potential for use in low-resource areas to prevent unnecessary rounds of MDA and to monitor for C. trachomatis recrudescence.
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Affiliation(s)
- Tamsyn R. Derrick
- Clinical Research Department, London School of Hygiene and Tropical Medicine, London, UK
- Eye Health Project, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Natalia Sandetskaya
- Department of Diagnostics, Fraunhofer Institute Cell Therapy and Immunology IZI, Leipzig, Germany
| | - Harry Pickering
- Clinical Research Department, London School of Hygiene and Tropical Medicine, London, UK
| | - Andreas Kölsch
- Department of Diagnostics, Fraunhofer Institute Cell Therapy and Immunology IZI, Leipzig, Germany
| | - Athumani Ramadhani
- Eye Health Project, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Elias Mafuru
- Eye Health Project, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Patrick Massae
- Eye Health Project, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Aiweda Malisa
- Eye Health Project, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Tara Mtuy
- Clinical Research Department, London School of Hygiene and Tropical Medicine, London, UK
- Eye Health Project, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Matthew J. Burton
- Clinical Research Department, London School of Hygiene and Tropical Medicine, London, UK
| | - Martin J. Holland
- Clinical Research Department, London School of Hygiene and Tropical Medicine, London, UK
| | - Dirk Kuhlmeier
- Department of Diagnostics, Fraunhofer Institute Cell Therapy and Immunology IZI, Leipzig, Germany
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Pickering H, Chernet A, Sata E, Zerihun M, Williams CA, Breuer J, Nute AW, Haile M, Zeru T, Tadesse Z, Bailey RL, Callahan EK, Holland MJ, Nash SD. Genomics of Ocular Chlamydia trachomatis after 5 years of SAFE interventions for trachoma in Amhara, Ethiopia. J Infect Dis 2020; 225:994-1004. [PMID: 33034349 PMCID: PMC8922003 DOI: 10.1093/infdis/jiaa615] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 09/30/2020] [Indexed: 12/18/2022] Open
Abstract
To eliminate trachoma as a public health problem, the WHO recommends the SAFE (Surgery, Antibiotics, Facial cleanliness, and Environmental improvement) strategy. As part of the SAFE strategy in the Amhara Region, Ethiopia, the Trachoma Control Program distributed over 124 million doses of antibiotic between 2007 and 2015. Despite this, trachoma remained hyperendemic in many districts and a considerable level of Chlamydia trachomatis (Ct) infection was evident. We utilised residual material from Abbott m2000 Ct diagnostic tests to sequence 99 ocular Ct samples from Amhara and investigated the role of Ct genomic variation in continued transmission of Ct. Sequences were typical of ocular Ct, at the whole-genome level and in tissue tropism-associated genes. There was no evidence of macrolide-resistance in this population. Polymorphism around ompA gene was associated with village-level trachomatous inflammation-follicular prevalence. Greater ompA diversity at the district-level was associated with increased Ct infection prevalence. We found no evidence for Ct genomic variation contributing to continued transmission of Ct after treatment, adding to evidence that azithromycin does not drive acquisition of macrolide resistance in Ct. Increased Ct infection in areas with more ompA variants requires longitudinal investigation to understand what impact this may have on treatment success and host immunity.
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Affiliation(s)
- Harry Pickering
- Department of Clinical Research, London School of Hygiene & Tropical Medicine, UK
| | | | | | | | | | - Judith Breuer
- Division of Infection and Immunity, University College London, UK
| | | | | | - Taye Zeru
- Amhara Public Health Institute Bahir Dar, Ethiopia
| | | | - Robin L Bailey
- Department of Clinical Research, London School of Hygiene & Tropical Medicine, UK
| | | | - Martin J Holland
- Department of Clinical Research, London School of Hygiene & Tropical Medicine, UK
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Versteeg B, Vasileva H, Houghton J, Last A, Shafi Abdurahman O, Sarah V, Macleod D, Solomon AW, Holland MJ, Thomson N, Burton MJ. Viability PCR shows that non-ocular surfaces could contribute to transmission of Chlamydia trachomatis infection in trachoma. PLoS Negl Trop Dis 2020; 14:e0008449. [PMID: 32667914 PMCID: PMC7384675 DOI: 10.1371/journal.pntd.0008449] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 07/27/2020] [Accepted: 06/03/2020] [Indexed: 11/24/2022] Open
Abstract
Background The presence of Chlamydia trachomatis (Ct) DNA at non-ocular sites suggests that these sites may represent plausible routes of Ct transmission in trachoma. However, qPCR cannot discriminate between DNA from viable and non-viable bacteria. Here we use a propodium monoazide based viability PCR to investigate how long Ct remains viable at non-ocular sites under laboratory-controlled conditions. Methods Cultured Ct stocks (strain A2497) were diluted to final concentrations of 1000, 100, 10 and 1 omcB copies/μL and applied to plastic, woven mat, cotton cloth and pig skin. Swabs were then systemically collected from each surface and tested for the presence Ct DNA using qPCR. If Ct DNA was recovered, Ct viability was assessed over time by spiking multiple areas of the same surface type with the same final concentrations. Swabs were collected from each surface at 0, 2, 4, 6, 8 and 24 hours after spiking. Viability PCR was used to determine Ct viability at each timepoint. Results We were able to detect Ct DNA on all surfaces except the woven mat. Total Ct DNA remained detectable and stable over 24 hours for all concentrations applied to plastic, pig skin and cotton cloth. The amount of viable Ct decreased over time. For plastic and skin surfaces, only those where concentrations of 100 or 1000 omcB copies/μL were applied still had viable loads detectable after 24 hours. Cotton cloth showed a more rapid decrease and only those where concentrations of 1000 omcB copies/μL were applied still had viable DNA detectable after 24 hours. Conclusion Plastic, cotton cloth and skin may contribute to transmission of the Ct strains that cause trachoma, by acting as sites where reservoirs of bacteria are deposited and later collected and transferred mechanically into previously uninfected eyes. Trachoma elimination efforts are hampered by limited understanding of Ct transmission routes. We have recently demonstrated the presence of Ct DNA at non-ocular sites in individuals living in households in Ethiopia where at least one resident had an ocular Ct infection detectable by quantitative PCR (qPCR). Ct DNA was most frequently detected on faces, hands and clothing, being found in such locations in 10–16% of samples tested. However, qPCR cannot discriminate between DNA from viable and non-viable organisms, and potentially misinform our understanding of Ct transmission routes. In this study, we used a propidium monoazide based viability PCR to investigate how long Ct remains viable on non-ocular sites by spiking different surfaces including pig skin, plastic and cotton cloth. These surfaces mimic non-ocular sites previously found to be positive for Ct DNA using standard qPCR. The results of our study show that viable Ct DNA could be recovered from plastic, cotton cloth and skin surfaces for up to 24 hours suggesting that these surfaces a role in ocular Ct transmission.
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Affiliation(s)
- Bart Versteeg
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
- * E-mail:
| | - Hristina Vasileva
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Joanna Houghton
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Anna Last
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Oumer Shafi Abdurahman
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
- The Fred Hollows Foundation, Addis Ababa, Ethiopia
| | | | - David Macleod
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Anthony W. Solomon
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Martin J. Holland
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Nicholas Thomson
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Parasites and Microbes, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Matthew J. Burton
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Moorfields Eye Hospital, London, United Kingdom
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11
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Czerniewska A, Versteeg A, Shafi O, Dumessa G, Aga MA, Last A, MacLeod D, Sarah V, Dodson S, Negussu N, Sori BK, Kirumba M, Biran A, Cairncross S, Burton MJ, Greenland K. Comparison of Face Washing and Face Wiping Methods for Trachoma Control: A Pilot Study. Am J Trop Med Hyg 2020; 102:740-743. [PMID: 32043457 PMCID: PMC7124903 DOI: 10.4269/ajtmh.19-0726] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 11/26/2019] [Indexed: 11/14/2022] Open
Abstract
Eye-to-eye transmission of Chlamydia trachomatis, the causative agent of trachoma, may be plausibly interrupted if faces are kept free of ocular and nasal discharge. Between April and June 2018, 83 children aged 1-9 years with active trachoma were recruited from 62 households and allocated to a face cleaning protocol: face washing with water, face washing with water and soap, or face wiping. Faces were examined for the presence of ocular and nasal discharge, and swabs were taken from faces and hands to test for C. trachomatis at baseline, immediately post protocol, and after 1, 2, and 4 hours (washing protocols). Washing with soap was more effective at removing ocular discharge than either washing with water (89% and 27% of discharge removed, respectively, P = 0.003) or wiping with a hand (42%, P = 0.013). The reduction in prevalence of ocular discharge was sustained for at least four hours. The prevalence of C. trachomatis on face swabs was reduced by all washing protocols. The importance of soap should not be overlooked during facial cleanliness promotion.
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Affiliation(s)
- Alexandra Czerniewska
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Aalbertus Versteeg
- Clinical Research Department, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Oumer Shafi
- Clinical Research Department, London School of Hygiene and Tropical Medicine, London, United Kingdom
- The Fred Hollows Foundation, Addis Ababa, Ethiopia
| | | | | | - Anna Last
- Clinical Research Department, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - David MacLeod
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | | | | | | | - Adam Biran
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Sandy Cairncross
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Matthew J. Burton
- Clinical Research Department, International Centre for Eye Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Cornea and External Eye Department, Moorfields Eye Hospital NHS Trust, London, United Kingdom
| | - Katie Greenland
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Immunopathogenesis of Progressive Scarring Trachoma: Results of a 4-Year Longitudinal Study in Tanzanian Children. Infect Immun 2020; 88:IAI.00629-19. [PMID: 31964744 PMCID: PMC7093124 DOI: 10.1128/iai.00629-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 01/15/2020] [Indexed: 12/25/2022] Open
Abstract
Trachoma is initiated during childhood following repeated conjunctival infection with Chlamydia trachomatis, which causes a chronic inflammatory response in some individuals that leads to scarring and in-turning of the eyelids in later life. There is currently no treatment to halt the progression of scarring trachoma due to an incomplete understanding of disease pathogenesis. A cohort study was performed in northern Tanzania in 616 children aged 6 to 10 years at enrollment. Every 3 months for 4 years, children were examined for clinical signs of trachoma, and conjunctival swabs were collected for C. trachomatis detection and to analyze the expression of 46 immunofibrogenic genes. Trachoma is initiated during childhood following repeated conjunctival infection with Chlamydia trachomatis, which causes a chronic inflammatory response in some individuals that leads to scarring and in-turning of the eyelids in later life. There is currently no treatment to halt the progression of scarring trachoma due to an incomplete understanding of disease pathogenesis. A cohort study was performed in northern Tanzania in 616 children aged 6 to 10 years at enrollment. Every 3 months for 4 years, children were examined for clinical signs of trachoma, and conjunctival swabs were collected for C. trachomatis detection and to analyze the expression of 46 immunofibrogenic genes. Data were analyzed in relation to progressive scarring status between baseline and the final time point. Genes that were significantly associated with scarring progression included those encoding proinflammatory chemokines (CXCL5, CCL20, CXCL13, and CCL18), cytokines (IL23A, IL19, and IL1B), matrix modifiers (MMP12 and SPARCL1), immune regulators (IDO1, SOCS3, and IL10), and a proinflammatory antimicrobial peptide (S100A7). In response to C. trachomatis infection, IL23A and PDGF were significantly upregulated in scarring progressors relative to in nonprogressors. Our findings highlight the importance of innate proinflammatory signals from the epithelium and implicate interleukin 23A (IL-23A)-responsive cells in driving trachomatous scarring, with potential key mechanistic roles for PDGFB, MMP12, and SPARCL1 in orchestrating fibrosis.
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Last A, Versteeg B, Shafi Abdurahman O, Robinson A, Dumessa G, Abraham Aga M, Shumi Bejiga G, Negussu N, Greenland K, Czerniewska A, Thomson N, Cairncross S, Sarah V, Macleod D, Solomon AW, Logan J, Burton MJ. Detecting extra-ocular Chlamydia trachomatis in a trachoma-endemic community in Ethiopia: Identifying potential routes of transmission. PLoS Negl Trop Dis 2020; 14:e0008120. [PMID: 32130213 PMCID: PMC7075638 DOI: 10.1371/journal.pntd.0008120] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 03/16/2020] [Accepted: 02/06/2020] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Trachoma elimination efforts are hampered by limited understanding of Chlamydia trachomatis (Ct) transmission routes. Here we aimed to detect Ct DNA at non-ocular sites and on eye-seeking flies. METHODS A population-based household survey was conducted in Oromia Region, Ethiopia. Ocular and non-ocular (faces, hands, clothing, water containers and sleeping surfaces) swabs were collected from all individuals. Flies were caught from faces of children. Flies, ocular swabs and non-ocular swabs were tested for Ct by quantitative PCR. RESULTS In total, 1220 individuals in 247 households were assessed. Active trachoma (trachomatous inflammation-follicular) and ocular Ct were detected in 10% and 2% of all-ages, and 21% and 3% of 1-9-year-olds, respectively. Ct was detected in 12% (95% CI:8-15%) of tested non-ocular swabs from ocular-positive households, but in none of the non-ocular swabs from ocular-negative households. Ct was detected on 24% (95% CI:18-32%) of flies from ocular-positive households and 3% (95% CI:1-6%) of flies from ocular-negative households. CONCLUSION Ct DNA was detected on hands, faces and clothing of individuals living in ocular-positive households suggesting that this might be a route of transmission within Ct infected households. In addition, we detected Ct on flies from ocular-positive households and occasionally in ocular-negative households suggesting that flies might be a vector for transmission within and between Ct infected and uninfected households. These potential transmission routes may need to be simultaneously addressed to suppress transmission.
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Affiliation(s)
- Anna Last
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Bart Versteeg
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Oumer Shafi Abdurahman
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
- The Fred Hollows Foundation, Ethiopia
| | - Ailie Robinson
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | | | | | | | - Katie Greenland
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Alexandra Czerniewska
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Nicholas Thomson
- Department of Pathogen Molecular Biology, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Parasites and microbes, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom
| | - Sandy Cairncross
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | - David Macleod
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Anthony W. Solomon
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - James Logan
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Matthew J. Burton
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
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Nie F, Gong Q, Yang J, Xi C, Wang Y, Wang G, Zhang L, Li X, Huo D, Hou C. Establishment of a Multiplex Real-Time TaqMan-MGB Polymerase Chain Reaction (PCR) Method for the Simultaneous Detection of Three Animal Chlamydia Species. Med Sci Monit 2019; 25:9369-9376. [PMID: 31814605 PMCID: PMC6921693 DOI: 10.12659/msm.918344] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Chlamydiae are spread globally and cause infectious diseases in both humans and animals. The existing detection methods for this disease have numerous shortcomings, including low sensitivity, time consuming procedures, and high contamination vulnerability. MATERIAL AND METHODS To overcome shortcomings for detecting animal chlamydiosis, a multiplex quantitative polymerase chain reaction (PCR) assay was established for simultaneously detecting and differentiating 3 Chlamydia species (C. pecorum, C. abortus, and C. psittaci) by real time PCR based on TaqMan-MGB technology. RESULTS The limit of detection was 20.2 copies/µL for Chlamydophila (Cp.) abortus, 30.8 copies/µL for Cp. pecorum, and 16 copies/µL for Cp. psittaci. This method has good repeatability and stability as coefficients of variation range from 0.04% to 1.38%. Furthermore, compared with OIE (World Organization for Animal Health) recommended PCR assay and previously reported animal chlamydia shell PCR, this multiplex PCR assay demonstrated 99% concordance in detecting clinical samples of porcine nasal swabs and vaginal swabs. CONCLUSIONS The novel established method in this study was able to detect 3 types of Chlamydia species simultaneously, and had high sensitivity, strong specificity, and good stability. It provided a rapid, reliable, and convenient method for epidemiological and clinical diagnosis of chlamydiosis in animals.
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Affiliation(s)
- Fuping Nie
- College of Biomedical Engineering, Chongqing University, Chongqing, China (mainland).,Chongqing Customs Technology Center, Chongqing Engineering Technology Research Center of Import and Export Food Safety, Chongqing, China (mainland)
| | - Qian Gong
- Chongqing Customs Technology Center, Chongqing Engineering Technology Research Center of Import and Export Food Safety, Chongqing, China (mainland)
| | - Jun Yang
- Chongqing Customs Technology Center, Chongqing Engineering Technology Research Center of Import and Export Food Safety, Chongqing, China (mainland)
| | - Cunxian Xi
- Chongqing Customs Technology Center, Chongqing Engineering Technology Research Center of Import and Export Food Safety, Chongqing, China (mainland)
| | - Yu Wang
- Chongqing Customs Technology Center, Chongqing Engineering Technology Research Center of Import and Export Food Safety, Chongqing, China (mainland)
| | - Guomin Wang
- Chongqing Customs Technology Center, Chongqing Engineering Technology Research Center of Import and Export Food Safety, Chongqing, China (mainland)
| | - Lei Zhang
- Chongqing Customs Technology Center, Chongqing Engineering Technology Research Center of Import and Export Food Safety, Chongqing, China (mainland)
| | - Xianliang Li
- Chongqing Customs Technology Center, Chongqing Engineering Technology Research Center of Import and Export Food Safety, Chongqing, China (mainland)
| | - Danqun Huo
- College of Biomedical Engineering, Chongqing University, Chongqing, China (mainland)
| | - Changjun Hou
- College of Biomedical Engineering, Chongqing University, Chongqing, China (mainland)
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Alkhidir AAI, Holland MJ, Elhag WI, Williams CA, Breuer J, Elemam AE, El Hussain KMK, Ournasseir MEH, Pickering H. Whole-genome sequencing of ocular Chlamydia trachomatis isolates from Gadarif State, Sudan. Parasit Vectors 2019; 12:518. [PMID: 31685017 PMCID: PMC6829945 DOI: 10.1186/s13071-019-3770-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 10/25/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Trachoma, caused by ocular Chlamydia trachomatis, is the leading infectious cause of blindness worldwide. Sudan first reported trachoma in the 1930s and has since been consistently endemic. Ocular C. trachomatis previously isolated from trachoma patients in Sudan in 1963 was antigenically identical to an isolate from Saudi Arabia (A/SA1). No contemporary ocular C. trachomatis whole genome sequences have been reported from Sudan. METHODS This study sequenced twenty ocular C. trachomatis isolates to improve understanding of pathogen diversity in North-East Africa and examine for genomic variation specific to Sudan, possibly related to the persistence of trachoma in surveyed communities. High quality, whole genome sequences were obtained from 12/20 isolates. RESULTS All isolates were serovar A and had tarP and trpA sequences typical of classical, ocular C. trachomatis isolates. The Sudanese isolates formed a closely related subclade within the T2-trachoma clade of C. trachomatis phylogeny distinct from geographically disparate ocular isolates, with little intra-population diversity. We found 333 SNPs that were conserved in Sudanese ocular isolates but rare compared to other ocular C. trachomatis populations, which were focused in two genomic loci (CTA0172-CTA0173 and CTA0482). CONCLUSIONS Limited intra-population diversity and geographical clustering of ocular C. trachomatis suggests minimal transmission between and slow diversification within trachoma-endemic communities. However, diversity may have been higher pre-treatment in these communities. Over-representation of Sudan-specific SNPs in three genes suggests they may have an impact on C. trachomatis growth and transmission in this population.
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Affiliation(s)
| | - Martin J Holland
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Wafa Ibrahim Elhag
- Faculty of Medical Laboratory Sciences, Al-Neelain University, Khartoum, Sudan
| | | | - Judith Breuer
- Division of Infection and Immunity, University College London, London, UK.,Microbiology, Virology, and Infection Control, Great Ormond Street Hospital for Children, NHS Foundation Trust, London, UK
| | | | | | | | - Harry Pickering
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
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Derrick T, Habtamu E, Tadesse Z, Callahan EK, Worku A, Gashaw B, Macleod D, Mabey DC, Holland MJ, Burton MJ. The conjunctival transcriptome in Ethiopians after trichiasis surgery: associations with the development of eyelid contour abnormalities and the effect of oral doxycycline treatment. Wellcome Open Res 2019. [DOI: 10.12688/wellcomeopenres.15419.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: Surgery to correct trichiasis is a key component of the World Health Organisation trachoma control strategy, however unfavourable outcomes such as eyelid contour abnormalities (ECA) following surgery are relatively common. This study aimed to understand the transcriptional changes associated with the early development of ECA and the impact of doxycycline, which has anti-inflammatory and anti-fibrotic properties, upon these transcription patterns. Methods: One thousand Ethiopians undergoing trichiasis surgery were enrolled in a randomised controlled trial following informed consent. Equal groups of randomly assigned individuals were orally administered with 100mg/day of doxycycline (n=499) or placebo (n=501) for 28 days. Conjunctival swabs were collected immediately prior to surgery and at one- and six-months post-surgery. 3’ mRNA sequencing was performed on paired baseline and one-month samples from 48 individuals; 12 in each treatment/ECA outcome group. qPCR validation was then performed for 46 genes of interest in 145 individuals who developed ECA at one month and 145 matched controls, using samples from baseline, one and six months. Results: All treatment/outcome groups upregulated genes associated with wound healing pathways at one month relative to baseline, however no individual differences were detected between groups. The summed expression of a highly coexpressed cluster of pro-fibrotic genes was higher in patients that developed ECA in the placebo group relative to controls. qPCR validation revealed that all genes in this cluster and a number of other pro-inflammatory genes were strongly associated with ECA, however these associations were not modulated by trial arm. Conclusions: The development of post-operative ECA is associated with overexpression of pro-inflammatory and pro-fibrotic genes including growth factors, matrix metalloproteinases, collagens and extracellular matrix proteins. There was no evidence that doxycycline modulated the association between gene expression and ECA.
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Ramadhani AM, Derrick T, Macleod D, Massae P, Mafuru E, Malisa A, Mbuya K, Roberts CH, Makupa W, Mtuy T, Bailey RL, Mabey DCW, Holland MJ, Burton MJ. Progression of scarring trachoma in Tanzanian children: A four-year cohort study. PLoS Negl Trop Dis 2019; 13:e0007638. [PMID: 31412025 PMCID: PMC6709924 DOI: 10.1371/journal.pntd.0007638] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 08/26/2019] [Accepted: 07/17/2019] [Indexed: 11/18/2022] Open
Abstract
Background Trachoma is a progressive blinding disease initiated by infection of the conjunctiva with Chlamydia trachomatis. Repeated infections are thought to cause chronic inflammation, which drives scarring, leading to in-turning of the eyelids. The relationship between C. trachomatis, clinical inflammation and scarring development in children is not fully understood due to a paucity of longitudinal studies with infection data at frequent follow-up. Methods and findings This longitudinal cohort study took place in northern Tanzania. Children aged 6–10 years at baseline were eligible for inclusion. Participants were visited every three months for four years. Clinical signs and conjunctival swabs for C. trachomatis detection by qPCR were collected at each time-point. Conjunctival photographs from baseline and final time-points were graded and compared side-by-side to determine scarring incidence and progression. Of the 666 children enrolled in the study, outcome data were obtained for 448. Scarring progression was detected in 103/448 (23%) children; 48 (11%) of which had incident scarring and 55 (12%) had progression of existing scarring. Scarring was strongly associated with increasing episodes of trachomatous papillary inflammation (TP). Weaker associations were found between episodes of C. trachomatis infection and follicular trachoma (TF) with scarring progression in unadjusted models, which were absent in multivariable analysis after adjusting for inflammation (multivariable results: C. trachomatis p = 0.44, TF p = 0.25, TP p = <0.0001, age p = 0.13, female sex p = 0.05). Individuals having TP at 30% or more of the time-points they were seen had an odds ratio of 7.5 (95%CI = 2.7–20.8) for scarring progression relative to individuals without any TP detected during the study period. Conclusions These data suggest that the effect of infection on scarring progression is mediated through papillary inflammation, and that other factors contributing to the development of inflammation, in addition to C. trachomatis infection, may be important in driving conjunctival scarring progression in children. The addition of TP as a measure in trachoma control programs would provide an indication of the future risk of developing scarring sequelae. Trachoma is the leading cause of preventable blindness worldwide and is targeted for elimination as a public health problem by 2020. The natural history of trachoma is not completely understood however. We conducted a four-year longitudinal study in a trachoma-endemic area of northern Tanzania with detailed follow up every three months. In the four-year study period, nearly one quarter of children developed progression of conjunctival scarring, despite three rounds of annual mass drug administration (MDA) for trachoma control. Disease progression was strongly associated with increasing proportion of episodes with conjunctival papillary inflammation (TP), and only weakly associated with Chlamydia trachomatis infection and trachomatous inflammation–follicular (TF). Analysis revealed that associations between infection and TF with scarring progression were mediated through TP, and that other factors causing individual differences in TP were also contributing to scarring progression. These data have significant implications for trachoma control. We hypothesise that in individuals who have previously experienced ocular C. trachomatis infection, TP is the primary driver of scarring progression. The addition of TP to trachoma surveillance programs would provide an indicator for active disease progression in the community and a more accurate guide to the need for future trichiasis interventions.
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Affiliation(s)
- Athumani M. Ramadhani
- London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- * E-mail:
| | - Tamsyn Derrick
- London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - David Macleod
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Elias Mafuru
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Aiweda Malisa
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Kelvin Mbuya
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | | | | | - Tara Mtuy
- London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Robin L. Bailey
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - David C. W. Mabey
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin J. Holland
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Matthew J. Burton
- London School of Hygiene and Tropical Medicine, London, United Kingdom
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18
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Ramadhani AM, Derrick T, Macleod D, Massae P, Malisa A, Mbuya K, Mtuy T, Makupa W, Roberts CH, Bailey RL, Mabey DCW, Holland MJ, Burton MJ. Ocular immune responses, Chlamydia trachomatis infection and clinical signs of trachoma before and after azithromycin mass drug administration in a treatment naïve trachoma-endemic Tanzanian community. PLoS Negl Trop Dis 2019; 13:e0007559. [PMID: 31306419 PMCID: PMC6658141 DOI: 10.1371/journal.pntd.0007559] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 07/25/2019] [Accepted: 06/18/2019] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Trachoma, caused by Chlamydia trachomatis, remains the leading infectious cause of blindness worldwide. Persistence and progression of the resulting clinical disease appears to be an immunologically mediated process. Azithromycin, which is distributed at the community level for trachoma control, has immunomodulatory properties. We investigated the impact of one round of oral azithromycin on conjunctival immune responses, C. trachomatis infection and clinical signs three- and six- months post treatment relative to three pre-treatment time-points. METHODOLOGY A cohort of children aged 6 to 10 years were recruited from a trachoma endemic region of northern Tanzania and were visited five times in a 12-month period. They were examined for clinical signs of trachoma and conjunctival swabs were collected for laboratory analysis. C. trachomatis infection was detected and the expression of 46 host genes was quantified using quantitative PCR. All community members were offered azithromycin treatment immediately after the six-month timepoint according to international guidelines. FINDINGS The prevalence of C. trachomatis infection and inflammatory disease signs were significantly reduced three- and six- months post-mass drug administration (MDA). C. trachomatis infection was strongly associated with clinical signs at all five time-points. A profound anti-inflammatory effect on conjunctival gene expression was observed 3 months post-MDA, however, gene expression had largely returned to pre-treatment levels of variation by 6 months. This effect was less marked, but still observed, after adjusting for C. trachomatis infection and when the analysis was restricted to individuals who were free from both infection and clinical disease at all five time-points. Interestingly, a modest effect was also observed in individuals who did not receive treatment. CONCLUSION Conjunctival inflammation is the major clinical risk factor for progressive scarring trachoma, therefore, the reduction in inflammation associated with azithromycin treatment may be beneficial in limiting the development of potentially blinding disease sequelae. Future work should seek to determine whether this effect is mediated directly through inhibition of pro-inflammatory intracellular signalling molecules, through reductions in concurrent, sub-clinical infections, and/or through reduction of infection exposure.
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Affiliation(s)
- Athumani M. Ramadhani
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Tamsyn Derrick
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - David Macleod
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Aiweda Malisa
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Kelvin Mbuya
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Tara Mtuy
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | | | - Chrissy H. Roberts
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Robin L. Bailey
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - David C. W. Mabey
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin J. Holland
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Matthew J. Burton
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
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19
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Kim JS, Oldenburg CE, Cooley G, Amza A, Kadri B, Nassirou B, Cotter SY, Stoller NE, West SK, Bailey RL, Keenan JD, Gaynor BD, Porco TC, Lietman TM, Martin DL. Community-level chlamydial serology for assessing trachoma elimination in trachoma-endemic Niger. PLoS Negl Trop Dis 2019; 13:e0007127. [PMID: 30689671 PMCID: PMC6366708 DOI: 10.1371/journal.pntd.0007127] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 02/07/2019] [Accepted: 01/04/2019] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Program decision-making for trachoma elimination currently relies on conjunctival clinical signs. Antibody tests may provide additional information on the epidemiology of trachoma, particularly in regions where it is disappearing or elimination targets have been met. METHODS A cluster-randomized trial of mass azithromycin distribution strategies for trachoma elimination was conducted over three years in a mesoendemic region of Niger. Dried blood spots were collected from a random sample of children aged 1-5 years in each of 24 study communities at 36 months after initiation of the intervention. A multiplex bead assay was used to test for antibodies to two Chlamydia trachomatis antigens, Pgp3 and CT694. We compared seropositivity to either antigen to clinical signs of active trachoma (trachomatous inflammation-follicular [TF] and trachomatous inflammation-intense [TI]) at the individual and cluster level, and to ocular chlamydia prevalence at the community level. RESULTS Of 988 children with antibody data, TF prevalence was 7.8% (95% CI 6.1 to 9.5) and TI prevalence was 1.6% (95% CI 0.9 to 2.6). The overall prevalence of antibody positivity to Pgp3 was 27.2% (95% CI 24.5 to 30), and to CT694 was 23.7% (95% CI 21 to 26.2). Ocular chlamydia infection prevalence was 5.2% (95% CI 2.8 to 7.6). Seropositivity to Pgp3 and/or CT694 was significantly associated with TF at the individual and community level and with ocular chlamydia infection and TI at the community level. Older children were more likely to be seropositive than younger children. CONCLUSION Seropositivity to Pgp3 and CT694 correlates with clinical signs and ocular chlamydia infection in a mesoendemic region of Niger. TRIAL REGISTRATION ClinicalTrials.gov NCT00792922.
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Affiliation(s)
- Jessica S. Kim
- F. I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
| | - Catherine E. Oldenburg
- F. I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America
| | - Gretchen Cooley
- Divison of Parasitic Diseases and Malaria, Centers for Disease Prevention and Control, Atlanta, Georgia, United States of America
| | - Abdou Amza
- Programme FSS/Université Abdou Moumouni de Niamey, Programme Nationale des Soins Oculaire, Niger
| | - Boubacar Kadri
- Programme FSS/Université Abdou Moumouni de Niamey, Programme Nationale des Soins Oculaire, Niger
| | - Baido Nassirou
- Programme FSS/Université Abdou Moumouni de Niamey, Programme Nationale des Soins Oculaire, Niger
| | - Sun Yu Cotter
- F. I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
| | - Nicole E. Stoller
- F. I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
| | - Sheila K. West
- Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Robin L. Bailey
- Clinical Research Unit, Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Jeremy D. Keenan
- F. I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America
| | - Bruce D. Gaynor
- F. I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
| | - Travis C. Porco
- F. I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America
- Institute for Global Health, University of California San Francisco, San Francisco, California, United States of America
| | - Thomas M. Lietman
- F. I. Proctor Foundation, University of California San Francisco, San Francisco, California, United States of America
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, California, United States of America
- Institute for Global Health, University of California San Francisco, San Francisco, California, United States of America
| | - Diana L. Martin
- Divison of Parasitic Diseases and Malaria, Centers for Disease Prevention and Control, Atlanta, Georgia, United States of America
- * E-mail:
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