RESUMO
Monitoring trachoma transmission with antibody data requires characterization of decay in IgG to Chlamydia trachomatis antigens. In a 3-year longitudinal cohort in a high-transmission setting, we estimated a median IgG half-life of 3 years and a seroreversion rate of 2.5 per 100 person-years (95% confidence interval, 1.6-3.5). Clinical Trials Registration NCT02754583.
Assuntos
Anticorpos Antibacterianos , Antígenos de Bactérias , Proteínas de Bactérias , Chlamydia trachomatis , Imunoglobulina G , Tracoma , Humanos , Etiópia/epidemiologia , Chlamydia trachomatis/imunologia , Antígenos de Bactérias/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Tracoma/epidemiologia , Tracoma/microbiologia , Tracoma/imunologia , Pré-Escolar , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Feminino , Masculino , Proteínas de Bactérias/imunologia , Lactente , Estudos Longitudinais , Criança , Doenças EndêmicasRESUMO
OBJECTIVES: A 6-week course of tetracycline eye ointment is an alternative to single -dose oral azithromycin in annual mass drug administration for trachoma control. Compliance with the recommended tetracycline eye ointment regimen has not been well characterised when administered as part of a trachoma control program. METHODS: A routine mass drug administration for trachoma was carried out in 40 communities in the Amhara region of Ethiopia. Two tubes of tetracycline eye ointment, to be administered twice daily for 6 weeks, was offered to all children under 6 months of age, to pregnant women who declined to take azithromycin, and to all individuals with a macrolide allergy. Seven weeks following the mass drug administration, a treatment compliance survey was performed for all community members documented to have received tetracycline eye ointment during the mass drug administration. RESULTS: Of the 491 individuals documented as having received tetracycline eye ointment from the treatment records, 367 completed the survey, of which 214 recalled being offered tetracycline eye ointment. A total of 105 (49%) respondents reported taking ≥1 daily dose of tetracycline eye ointment on most days of the week for at least the first week. Only 20 (9%) respondents reported taking at least 1 tetracycline eye ointment dose per week for 6 weeks. The most common reasons for low compliance included 'saving it for a future infection' and 'stopped because I (or my child) seemed healthy'. The odds of low compliance were greater for those who reported not having adequate counselling (e.g., odds ratio [OR] 5.3, 95% CI 2.5-28.9 when low compliance was defined as not taking a tetracycline eye ointment dose for most days of at least the first week). CONCLUSIONS: Compliance with tetracycline eye ointment was low when administered by a trachoma program during a routine mass drug administration, especially for those reporting inadequate counselling. Further research with a larger sample size and varied settings is warranted to better understand and improve compliance.
RESUMO
Understanding how land use types embedded in agricultural landscapes support forest biodiversity is critical, especially during this period of continuing fragmentation and habitat losses in natural ecosystems. Here, we explored the floristic species composition with respect to land use types in the agroecosystem of west Oromia, Ethiopia. For this, a systematic sampling method was employed to collect floristic data from 122 main quadrats and 610 sub-quadrats, following transects laid out with a 1500-m interval. The main quadrats were arranged on transects with an 800-m interval to assess woody species, and five sub-quadrats (i.e., four at the corners and one at the center) were taken within each main plot to assess herbaceous plants. Accordingly, the floristics were assessed with respect to the identified five land use types, including crop land, forest, grazing land, home gardens, and riverine. We used a one-way ANOVA to test the difference in species diversity among the land use types. Adonis 2 and indval functions were used to describe the species composition and indicator species in relation to the land use types. Moreover, NMDS was applied to visualize the associations of the species composition with environmental variables in ordination space. A total of 285 plant species belonging to 220 genera and 89 families were recorded. Our results showed significant differences in species diversity, dissimilarity in species composition, and species indicator values among the land use types. These results indicate that the potentiality of the land use types in supporting plant diversity is significantly different; for example, species diversity and abundances were higher in grazing lands and home gardens when compared with other land use types. Overall, our findings suggest that conservation strategies in agricultural landscapes should take into account the differences in capacity for supporting biodiversity among land use types when planning.
RESUMO
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.
Assuntos
Proteínas da Membrana Bacteriana Externa , Chlamydia trachomatis , Genótipo , Repetições Minissatélites , Tracoma , Chlamydia trachomatis/genética , Chlamydia trachomatis/isolamento & purificação , Chlamydia trachomatis/classificação , Tracoma/epidemiologia , Tracoma/microbiologia , Tracoma/tratamento farmacológico , Humanos , Etiópia/epidemiologia , Repetições Minissatélites/genética , Proteínas da Membrana Bacteriana Externa/genética , Feminino , Masculino , Pré-Escolar , Tipagem Molecular/métodos , Azitromicina/uso terapêutico , Variação Genética , Lactente , Criança , Antibacterianos/farmacologia , DNA Bacteriano/genéticaRESUMO
The SAFE (Surgery, Antibiotics, Facial cleanliness, Environmental improvement) strategy is the WHO's endorsed approach for eliminating trachoma as a public health problem; however, not all components have been treated equally. Historically, the F and E components have not been prioritized owing to their perceived complexity. With school enrollment increasing in Ethiopia, development of a national school health program that is focused on the F and E components represents an opportunity to strengthen the SAFE strategy in the country. In 2016, the Trachoma Control Program in Amhara, Ethiopia, along with its partners, developed a School Trachoma Program (STP) that offers grade-specific lessons to improve sanitation and hygiene knowledge and practices among primary school-aged children. To assess its impact, schools were sampled before implementation and then up to 1 year after STP rollout. The aim of this report is to detail STP outcomes and the associations between outcomes and school-level variables. By 2018, adoption of an STP was strong within Amhara, with 85% of the 137 surveyed schools completing their quarterly reports and nearly 80% having at least one teacher trained in the STP. By the end of the third quarter, nearly all schools (86%) had access to a latrine, and 89% of students had a clean face. A schoolwide orientation was associated with increased STP lessons and activities (P = 0.01). Development of an STP, with buy-in from principals and teachers, represents a promising approach for the adoption of a new F- and E-specific curriculum and may help advance efforts to eliminate trachoma.
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BACKGROUND: Trachoma recrudescence after elimination as a public health problem has been reached is a concern for control programs globally. Programs typically conduct district-level trachoma surveillance surveys (TSS) ≥ 2 years after the elimination threshold is achieved to determine whether the prevalence of trachomatous inflammation-follicular (TF) among children ages 1 to 9 years remains <5%. Many TSS are resulting in a TF prevalence ≥5%. Once a district returns to TF ≥5%, a program typically restarts costly mass drug administration (MDA) campaigns and surveys at least twice, for impact and another TSS. In Amhara, Ethiopia, most TSS which result in a TF ≥5% have a prevalence close to 5%, making it difficult to determine whether the result is due to true recrudescence or to statistical variability. This study's aim was to monitor recrudescence within Amhara by waiting to restart MDA within 2 districts with a TF prevalence ≥5% at TSS, Metema = 5.2% and Woreta Town = 5.1%. The districts were resurveyed 1 year later using traditional and alternative indicators, such as measures of infection and serology, a "wait and watch" approach. METHODS/PRINCIPAL FINDINGS: These post-surveillance surveys, conducted in 2021, were multi-stage cluster surveys whereby certified graders assessed trachoma signs. Children ages 1 to 9 years provided a dried blood spot and children ages 1 to 5 years provided a conjunctival swab. TF prevalence in Metema and Woreta Town were 3.6% (95% Confidence Interval [CI]:1.4-6.4) and 2.5% (95% CI:0.8-4.5) respectively. Infection prevalence was 1.2% in Woreta Town and 0% in Metema. Seroconversion rates to Pgp3 in Metema and Woreta Town were 0.4 (95% CI:0.2-0.7) seroconversions per 100 child-years and 0.9 (95% CI:0.6-1.5) respectively. CONCLUSIONS/SIGNIFICANCE: Both study districts had a TF prevalence <5% with low levels of Chlamydia trachomatis infection and transmission, and thus MDA interventions are no longer warranted. The wait and watch approach represents a surveillance strategy which could lead to fewer MDA campaigns and surveys and thus cost savings with reduced antibiotic usage.
Assuntos
Tracoma , Humanos , Lactente , Tracoma/tratamento farmacológico , Tracoma/epidemiologia , Tracoma/prevenção & controle , Etiópia/epidemiologia , Antibacterianos/uso terapêutico , Inflamação/tratamento farmacológico , Prevalência , Recidiva , Chlamydia trachomatisRESUMO
Persistent trachoma is a growing concern to trachoma control programs globally and programs serving Ethiopia specifically. Persistent trachoma is defined as a district with two or more trachoma impact surveys (TISs) at which the prevalence of trachomatous inflammation-follicular (TF) among children ages 1-9 years is ≥5%, the elimination threshold. Because the global target for trachoma elimination as a public health problem is 2030, research is needed to better characterize persistent trachoma. This study described the epidemiology of ocular Chlamydia trachomatis infection, the causative bacteria of trachoma, in seven contiguous districts experiencing persistent trachoma. In 2019, multistage cluster random sampling TISs were conducted in the seven districts after 10 years of interventions. All individuals ages ≥1 year were examined for trachoma clinical signs by certified graders, and conjunctival swabs were collected from children ages 1-5 years to test for C. trachomatis infection. The district TF prevalence ranged from 11.8% (95% CI:7.6-16.0%) to 36.1% (95% CI:27.4-44.3%). The range of district-level C. trachomatis infection prevalence was between 2.7% and 34.4%. Statistically significant spatial clustering of high-infection communities was observed in the study districts, and children with infection were more likely than those without to be found in households with clinical signs of trachoma and those without latrines. These seven districts appear to constitute a persistent hotspot in Amhara, where an additional 3-5 years or more of interventions will be required. The global program will need to strengthen and enhance intervention strategies within persistent districts if elimination by 2030 is to be achieved.