Corneal pannus, Herbert's pits and conjunctival inflammation in older children in Papua New Guinea.

PURPOSE: The prevalence of trachomatous inflammation-follicular (TF) in Papua New Guinea (PNG) suggests antibiotic mass drug administration (MDA) is needed to eliminate trachoma as a public health problem but the burden of trichiasis is low. As a result, WHO issued bespoke recommendations for the region. If ≥ 20% of 10-14-year-olds have both any conjunctival scarring (C1 or C2 or C3) and corneal pannus and/or Herbert's pits, MDA should be continued. Equally, if ≥ 5% of that group have both moderate/severe conjunctival scarring (C2 or C3) and corneal pannus and/or Herbert's pits, MDA should be continued. METHODS: We identified 14 villages where > 20% of 1-9-year-olds had TF during baseline mapping undertaken 4 years and 1 month previously. Every child aged 10-14 years in those villages was eligible to be examined for clinical signs of corneal pannus, Herbert's pits and conjunctival scarring. A grading system that built on existing WHO grading systems was used. RESULTS: Of 1,293 resident children, 1,181 (91%) were examined. Of 1,178 with complete examination data, only one (0.08%) individual had concurrent scarring and limbal signs. CONCLUSIONS: The WHO-predefined criteria for continuation of MDA were not met. Ongoing behavioural and environmental improvement aspects of the SAFE strategy may contribute to integrated NTD control. Surveillance methods should be strengthened to enable PNG health authorities to identify future changes in disease prevalence.

Conjunctival Scarring, Corneal Pannus, and Herbert's Pits in Adolescent Children in Trachoma-endemic Populations of the Solomon Islands and Vanuatu.

BACKGROUND: In the Solomon Islands and Vanuatu, the sign trachomatous inflammation-follicular (TF) is common, but ocular infection with Chlamydia trachomatis is not. It is therefore debatable whether azithromycin mass drug administration (MDA), the recommended antibiotic treatment strategy for trachoma's elimination as a public health problem, is necessary in this setting. We set out to estimate what proportion of adolescents were at risk of progression of trachomatous scarring. METHODS: A cross-sectional survey was undertaken of all children aged 10-14 years resident in communities identified as high-TF clusters during previous population-based mapping. Graders examined children for clinical evidence of trachomatous scarring, pannus, and Herbert's pits (HPs) or limbal follicles in both eyes. A dried blood spot was collected from each child and tested for antibodies to C. trachomatis. RESULTS: A total of 492 children in 24 villages of the Solomon Islands and Vanuatu were examined. In total, 35/492 (7%) of children had limbal signs (pannus and/or HPs) plus any conjunctival scarring. And 9/492 (2%) had limbal signs and moderate or severe conjunctival scarring; 22% of children were anti-Pgp3 seropositive. CONCLUSIONS: Few adolescents here are at risk of future complications from trachoma, supporting the conclusion that further antibiotic MDA is not currently required for trachoma elimination purposes in these settings.

A diagnostic instrument to help field graders evaluate active trachoma.

The SAFE strategy (Surgery for trichiasis, mass treatment with Antibiotics to clear ocular Chlamydia trachomatis infection, and Facial cleanliness and Environmental improvement to reduce transmission) is being used to eliminate trachoma as a public health problem. Decisions on whether or not to implement the A, F, and E components of SAFE are made on the basis of the prevalence of trachomatous inflammation-follicular (TF) in 1-9-year-olds. TF has a precise definition: at least five follicles, each of which is at least 0.5-mm diameter, in the central part of the upper tarsal conjunctiva. Determining whether a follicle has a diameter ≥0.5mm is difficult using magnifying loupes alone. We have developed an ultra-low-cost solution: a follicle size guide that takes the form of a durable printed adhesive sticker which can be fixed to graders' thumb nails for direct size comparison. This tool will be made available to health ministries free of charge. It is anticipated to simplify grader training, increase grader trainee pass rates, and prevent in-service diagnostic drift after training is complete.

Prevalence of signs of trachoma, ocular Chlamydia trachomatis infection and antibodies to Pgp3 in residents of Kiritimati Island, Kiribati.

OBJECTIVE: In some Pacific Island countries, such as Solomon Islands and Fiji, active trachoma is common, but ocular Chlamydia trachomatis (Ct) infection and trachomatous trichiasis (TT) are rare. On Tarawa, the most populous Kiribati island, both the active trachoma sign "trachomatous inflammation-follicular" (TF) and TT are present at prevalences warranting intervention. We sought to estimate prevalences of TF, TT, ocular Ct infection, and anti-Ct antibodies on Kiritimati Island, Kiribati, to assess local relationships between these parameters, and to help determine the need for interventions against trachoma on Kiribati islands other than Tarawa. METHODS: As part of the Global Trachoma Mapping Project (GTMP), on Kiritimati, we examined 406 children aged 1-9 years for active trachoma. We collected conjunctival swabs (for droplet digital PCR against Ct plasmid targets) from 1-9-year-olds with active trachoma, and a systematic selection of 1-9-year-olds without active trachoma. We collected dried blood spots (for anti-Pgp3 ELISA) from all 1-9-year-old children. We also examined 416 adults aged ≥15 years for TT. Prevalence of TF and TT was adjusted for age (TF) or age and gender (TT) in five-year age bands. RESULTS: The age-adjusted prevalence of TF in 1-9-year-olds was 28% (95% confidence interval [CI]: 24-35). The age- and gender-adjusted prevalence of TT in those aged ≥15 years was 0.2% (95% CI: 0.1-0.3%). Twenty-six (13.5%) of 193 swabs from children without active trachoma, and 58 (49.2%) of 118 swabs from children with active trachoma were positive for Ct DNA. Two hundred and ten (53%) of 397 children had anti-Pgp3 antibodies. Both infection (p<0.0001) and seropositivity (p<0.0001) were strongly associated with active trachoma. In 1-9-year-olds, the prevalence of anti-Pgp3 antibodies rose steeply with age. CONCLUSION: Trachoma presents a public health problem on Kiritimati, where the high prevalence of ocular Ct infection and rapid increase in seropositivity with age suggest intense Ct transmission amongst young children. Interventions are required here to prevent future blindness.

Active Trachoma Cases in the Solomon Islands Have Varied Polymicrobial Community Structures but Do Not Associate with Individual Non-Chlamydial Pathogens of the Eye.

BACKGROUND: Several non-chlamydial microbial pathogens are associated with clinical signs of active trachoma in trachoma-endemic communities with a low prevalence of ocular Chlamydia trachomatis (Ct) infection. In the Solomon Islands, the prevalence of Ct among children is low despite the prevalence of active trachoma being moderate. Therefore, we set out to investigate whether active trachoma was associated with a common non-chlamydial infection or with a dominant polymicrobial community dysbiosis in the Solomon Islands. METHODS: We studied DNA from conjunctival swabs collected from 257 Solomon Islanders with active trachoma and matched controls. Droplet digital PCR was used to test for pathogens suspected to be able to induce follicular conjunctivitis. Polymicrobial community diversity and composition were studied by sequencing of hypervariable regions of the 16S ribosomal ribonucleic acid gene in a subset of 54 cases and 53 controls. RESULTS: Although Ct was associated with active trachoma, the number of infections was low (cases, 3.9%; controls, 0.4%). Estimated prevalence (cases and controls, respectively) of each non-chlamydial infection was as follows: Staphylococcus aureus: 1.9 and 1.9%, Adenoviridae: 1.2 and 1.2%, coagulase-negative Staphylococcus: 5.8 and 4.3%, Haemophilus influenzae: 7.4 and 11.7%, Moraxella catarrhalis: 2.3 and 4.7%, and Streptococcus pneumoniae: 7.0 and 6.2%. There was no statistically significant association between the clinical signs of trachoma and the presence or load of any of the non-Ct infections that were assayed. Interindividual variations in the conjunctival microbiome were characterized by differences in the levels of Corynebacterium, Propionibacterium, Helicobacter, and Paracoccus, but diversity and relative abundance of these specific genera did not differ significantly between cases and controls. DISCUSSION: It is unlikely that the prevalent trachoma-like follicular conjunctivitis in this region of the Solomon Islands has a dominant bacterial etiology. Before implementing community-wide azithromycin distribution for trachoma, policy makers should consider that clinical signs of trachoma can be observed in the absence of any detectable azithromycin-susceptible organism.

Correction: Low Prevalence of Conjunctival Infection with Chlamydia trachomatis in a Treatment-Naïve Trachoma-Endemic Region of the Solomon Islands.

[This corrects the article DOI: 10.1371/journal.pntd.0004863.].

Low Prevalence of Conjunctival Infection with Chlamydia trachomatis in a Treatment-Naïve Trachoma-Endemic Region of the Solomon Islands.

BACKGROUND: Trachoma is endemic in several Pacific Island states. Recent surveys across the Solomon Islands indicated that whilst trachomatous inflammation-follicular (TF) was present at levels warranting intervention, the prevalence of trachomatous trichiasis (TT) was low. We set out to determine the relationship between chlamydial infection and trachoma in this population. METHODS: We conducted a population-based trachoma prevalence survey of 3674 individuals from two Solomon Islands provinces. Participants were examined for clinical signs of trachoma. Conjunctival swabs were collected from all children aged 1-9 years. We tested swabs for Chlamydia trachomatis (Ct) DNA using droplet digital PCR. Chlamydial DNA from positive swabs was enriched and sequenced for use in phylogenetic analysis. RESULTS: We observed a moderate prevalence of TF in children aged 1-9 years (n = 296/1135, 26.1%) but low prevalence of trachomatous inflammation-intense (TI) (n = 2/1135, 0.2%) and current Ct infection (n = 13/1002, 1.3%) in children aged 1-9 years, and TT in those aged 15+ years (n = 2/2061, 0.1%). Ten of 13 (76.9%) cases of infection were in persons with TF or TI (p = 0.0005). Sequence analysis of the Ct-positive samples yielded 5/13 (38%) complete (>95% coverage of reference) genome sequences, and 8/13 complete plasmid sequences. Complete sequences all aligned most closely to ocular serovar reference strains. DISCUSSION: The low prevalence of TT, TI and Ct infection that we observed are incongruent with the high proportion of children exhibiting signs of TF. TF is present at levels that apparently warrant intervention, but the scarcity of other signs of trachoma indicates the phenotype is mild and may not pose a significant public health threat. Our data suggest that, whilst conjunctival Ct infection appears to be present in the region, it is present at levels that are unlikely to be the dominant driving force for TF in the population. This could be one reason for the low prevalence of TT observed during the study.

Cataract surgical outcomes from a large-scale micro-surgical campaign in China.

PURPOSE: To assess cataract surgical outcomes during the Jiangxi Provincial Government's "Brightness and Smile Initiative" (BSI) in South East China during May 2009 to July 2010. METHOD: This cross sectional combined with retrospective study included 1157 cataract surgical patients (1254 eyes) recruited from six counties in Jiangxi during the initiative. Patient information before surgery and at discharge was obtained from hospitals' case records. Patient follow-up eye examinations were conducted during field visits in the autumn of 2010. Fifteen months after the initiative started, study subjects were examined by provincial ophthalmologists using a Snellen visual chart, portable slit lamp, torch and ophthalmoscope. The World Health Organization (WHO) cataract surgical outcome monitoring tally sheet and the outcome categories good (visual acuity, VA, ≥ 0.3 (6/18)), borderline (VA <0.3 but ≥ 0.1 (6/60)) and poor (VA < 0.1) were used for data collection and analysis. RESULTS: A total of 99.7% of operated patients had intraocular lenses implanted. The percentage of eyes with good outcomes (presenting VA) at follow-up was low (49.6%), while the borderline and poor outcome rates were high (34.1% and 16.3%, respectively), in comparison to WHO recommendations. There was a significant outcome difference at follow-up (p < 0.01) between eyes operated by county surgeons trained by an International Non-Government Organization and those operated on by other visiting surgeons. CONCLUSIONS: This study documented a low rate of good cataract surgical outcomes from the BSI in Jiangxi. The quality of cataract surgery should be improved further in the province.

A global survey of low vision service provision.

PURPOSE: To conduct a global survey of low vision services to describe the needs, priorities, and barriers in provision and coverage. METHODS: Data were mainly derived from a survey and from some secondary sources. The survey was distributed to Vision 2020 contacts, government, and non-government organizations (NGOs) in 195 countries during 2006-2008. Themes in the survey were: epidemiology of low vision, policies on low vision, provision of services, human resources, barriers to service delivery, equipment availability, and monitoring and evaluation of service outcomes. Contradictory and/or incomplete data were returned for further clarification and verification. The Human Poverty Index was used to compare the findings from developed and developing countries. RESULTS: Service availability was established for 178/195 countries, with 115 having some low vision service. Approximately half the countries in the African and Western Pacific regions have no services. Few countries have >10 low vision health professionals per 10 million of population. In many of the countries NGOs were the main providers and funders. Funding and awareness were frequently cited as barriers to service access. Women, people with disabilities, and rural dwellers were less likely to access services. There were few reports of monitoring and evaluation into the quality and impact of services. CONCLUSION: This global survey provides the first consolidated baseline of low vision service provision. Where data are available, coverage of services is generally poor. Low vision health professional numbers are low. Services in over half of the world's countries are funded by NGOs, raising issues of sustainability.

What is the appropriate age range of individuals to be included in a survey to estimate the prevalence of trachomatous trichiasis?

INTRODUCTION: A survey to determine the prevalence of trachomatous trichiasis (TT) requires a large sample size and the recommended participant age is ≥15 years. This study sought to establish the appropriate age range of individuals to be included in TT surveys. METHODS: Data from six previous surveys of adults ≥15 years old were reanalysed. RESULTS: Reanalysis indicated that 69.6-93.3% (average 87.0%) of untreated TT occurred in those aged 40+ years and 52.2-86.7% (average 73.1%) in those aged 50+ years (age ≥50 years is used in rapid assessment of avoidable blindness). Age ≥40 years was adopted in a TT survey conducted in Turkana district because it allowed a smaller sample size than age ≥15 years. CONCLUSIONS: The estimated backlog of untreated TT in people aged ≥40 years old in Turkana was 5932 and the overall TT backlog was likely to be 6358-8523. These findings cannot be generalised because all surveys were carried out in the same country.

Validation of a quality of life questionnaire in the Pacific Island.

PURPOSE: To adapt an existing validated quality of life instrument, the Impact of Vision Impairment (IVI) questionnaire for Pacific Island countries. METHODS: Following in-depth interviews (n = 24) and a pilot study (n = 67), the original 32-item IVI questionnaire was translated and adapted in Vanuatu. The Melanesian IVI (IVI_M) was administered to participants not previously involved in the pilot study (n = 189). RESULTS: Participants included 117 (62%) with mild, moderate or severe vision impairment, 39 with unilateral loss and 33 with normal vision. Eighty-six percent of the original 32-items were deemed relevant by 90% of participants. Items displaying floor effects were removed (4), 2 were combined and 3 items rephrased to reflect Melanesian-specific activities, resulting in a 23-item IVI_M. Nineteen items were relevant to both the Melanesian and Australian contexts including all 8 items related to the emotional reaction to vision loss. IVI_M demonstrated content and construct validity, reliability and discriminated visually healthy populations from those with vision impairment. Vision impairment of < 6/18 negatively effected quality of life. CONCLUSION: While the adaptation process demonstrated the need for culturally relevant instruments, it also highlighted the value of adapting existing validated instrument for use in cross-cultural research rather than developing a new instrument from first principles.