Evidence map›Paper›PMID 38662795›Full record

ArticlePLoS neglected tropical diseases2024

Unravelling Chlamydia trachomatis diversity in Amhara, Ethiopia: MLVA-ompA sequencing as a molecular typing tool for trachoma.

Anna J Harte, Ehsan Ghasemian, Harry Pickering, Joanna Houghton, Ambahun Chernet, Eshetu Sata, Gizachew Yismaw, Taye Zeru, Zerihun Tadesse, E Kelly Callahan and 2 more

Open access · goldAbstract read
In one paragraph

Article in PLoS neglected tropical diseases, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
1.0field-weighted citation impact, top 25% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 3 citations in OpenAlex.

  1. Article
  2. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

12 authors at 4 institutions in 3 countries.

Anna J HarteThe London School of Hygiene and Tropical Medicine, London, United Kingdom.ORCID 0000-0001-7338-7654
Ehsan GhasemianThe London School of Hygiene and Tropical Medicine, London, United Kingdom.
Harry PickeringThe London School of Hygiene and Tropical Medicine, London, United Kingdom.
Joanna HoughtonThe London School of Hygiene and Tropical Medicine, London, United Kingdom.
Ambahun ChernetThe Carter Center, Addis Ababa, Ethiopia.
Eshetu SataThe Carter Center, Addis Ababa, Ethiopia.
Gizachew YismawThe Amhara Regional Health Bureau, Bahir Dar, Ethiopia.
Taye ZeruThe Amhara Regional Health Bureau, Bahir Dar, Ethiopia.
Zerihun TadesseThe Carter Center, Addis Ababa, Ethiopia.
E Kelly CallahanThe Carter Center, Atlanta, Georgia, United States of America.
Scott D NashThe Carter Center, Atlanta, Georgia, United States of America.
Martin J HollandThe London School of Hygiene and Tropical Medicine, London, United Kingdom.ORCID 0000-0002-5828-6318
London School of Hygiene & Tropical Medicine · GBThe Carter Center · ETAmhara Regional Health Bureau · ETCarter Center · US

Funding

Austrian Science Fund (FWF)Bill & Melinda Gates FoundationUnited Kingdom Department for International DevelopmentUnited States Agency for International Development
6 · The paper itself

Abstract

Trachoma is the leading infectious cause of blindness worldwide and is now largely confined to around 40 low- and middle-income countries. It is caused by Chlamydia trachomatis (Ct), a contagious intracellular bacterium. The World Health Organization recommends mass drug administration (MDA) with azithromycin for treatment and control of ocular Ct infections, alongside improving facial cleanliness and environmental conditions to reduce transmission. To understand the molecular epidemiology of trachoma, especially in the context of MDA and transmission dynamics, the identification of Ct genotypes could be useful. While many studies have used the Ct major outer membrane protein gene (ompA) for genotyping, it has limitations. Our study applies a typing system novel to trachoma, Multiple Loci Variable Number Tandem Repeat Analysis combined with ompA (MLVA-ompA). Ocular swabs were collected post-MDA from four trachoma-endemic zones in Ethiopia between 2011-2017. DNA from 300 children with high Ct polymerase chain reaction (PCR) loads was typed using MLVA-ompA, utilizing 3 variable number tandem repeat (VNTR) loci within the Ct genome. Results show that MLVA-ompA exhibited high discriminatory power (0.981) surpassing the recommended threshold for epidemiological studies. We identified 87 MLVA-ompA variants across 26 districts. No significant associations were found between variants and clinical signs or chlamydial load. Notably, overall Ct diversity significantly decreased after additional MDA rounds, with a higher proportion of serovar A post-MDA. Despite challenges in sequencing one VNTR locus (CT1299), MLVA-ompA demonstrated cost-effectiveness and efficiency relative to whole genome sequencing, providing valuable information for trachoma control programs on local epidemiology. The findings suggest the potential of MLVA-ompA as a reliable tool for typing ocular Ct and understanding transmission dynamics, aiding in the development of targeted interventions for trachoma control.

Indexed as

Bacterial Outer Membrane ProteinsChlamydia trachomatisGenotypeMinisatellite RepeatsTrachomaAnti-Bacterial AgentsAzithromycinChildChild, PreschoolDNA, BacterialEthiopiaFemaleGenetic VariationHumansInfantMaleAnti-Bacterial AgentsAzithromycinBacterial Outer Membrane ProteinsDNA, BacterialOMPA outer membrane proteins

Identifiers

PMID38662795
PMCPMC11075894
OpenAlexW4395447568

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.