Trachoma, Anti-Pgp3 Serology, and Ocular Chlamydia trachomatis Infection in Papua New Guinea.

BACKGROUND: In Melanesia, the prevalence of trachomatous inflammation-follicular (TF) suggests that public health-level interventions against active trachoma are needed. However, the prevalence of trachomatous trichiasis is below the threshold for elimination as a public health problem and evidence of conjunctival infection with trachoma's causative organism (Chlamydia trachomatis [CT]) is rare. Here, we examine the prevalence of ocular infection with CT and previous exposure to CT in three evaluation units (EUs) of Papua New Guinea. METHODS: All individuals aged 1-9 years who were examined for clinical signs of trachoma in 3 Global Trachoma Mapping Project EUs were eligible to take part in this study (N = 3181). Conjunctival swabs were collected from 349 children with TF and tested by polymerase chain reaction to assess for ocular CT infection. Dried blood spots were collected from 2572 children and tested for anti-Pgp3 antibodies using a multiplex assay. RESULTS: The proportion of children with TF who had CT infection was low across all 3 EUs (overall 2%). Anti-Pgp3 seroprevalence was 5.2% overall and there was no association between anti-Pgp3 antibody level and presence of TF. In 2 EUs, age-specific seroprevalence did not increase significantly with increasing age in the 1- to 9-year-old population. In the third EU, there was a statistically significant change with age but the overall seroprevalence and peak age-specific seroprevalence was very low. CONCLUSIONS: Based on these results, together with similar findings from the Solomon Islands and Vanuatu, the use of TF to guide antibiotic mass drug administration decisions in Melanesia should be reviewed.

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.

Rapid assessment of avoidable blindness in Papua New Guinea: a nationwide survey.

OBJECTIVE: To estimate the prevalence and main causes of blindness and vision impairment in people aged 50 years and older in Papua New Guinea (PNG). DESIGN: National cross-sectional population-based survey in National Capital District (NCD), Highlands, Coastal and Islands regions. METHODS: Adults aged 50 years and above were recruited from 100 randomly selected clusters. Each participant underwent monocular presenting and pinhole visual acuity (VA) assessment and lens examination. Those with pinhole VA<6/12 in either eye had a dilated fundus examination to determine the primary cause of reduced vision. Those with obvious lens opacity were interviewed on barriers to cataract surgery. RESULTS: A total of 4818 adults were examined. The age-adjusted and sex-adjusted prevalence of blindness (VA <3/60), severe vision impairment (SVI, VA <6/60 but ≥3/60), moderate vision impairment (MVI, VA <6/18 but ≥6/60) and early vision impairment (EVI, VA <6/12 but ≥6/18) was 5.6% (95% CI 4.9% to 6.3%), 2.9% (95% CI 2.5% to 3.4%), 10.9% (95% CI 9.9% to 11.9%) and 7.3% (95% CI 6.6% to 8.0%), respectively. The main cause of blindness, SVI and MVI was cataract, while uncorrected refractive error was the main cause of EVI. A significantly higher prevalence of blindness, SVI and MVI occurred in the Highlands compared with NCD. Across all regions, women had lower cataract surgical coverage and spectacle coverage than men. CONCLUSIONS: PNG has one of the highest reported prevalence of blindness globally. Cataract and uncorrected refractive error are the main causes, suggesting a need for increased accessible services with improved resources and advocacy for enhancing eye health literacy.

Rapid assessment of avoidable blindness and diabetic retinopathy in people aged 50 years and older in the National Capital District of Papua New Guinea.

BACKGROUND/AIMS: To conduct an assessment of avoidable blindness, diabetes mellitus and diabetic retinopathy (DR) in adults aged 50 years and older in the National Capital District (NCD) region of Papua New Guinea (PNG). METHODS: A cross-sectional population-based survey was performed for which 25 clusters of 50 people aged ≥50 years were randomly selected from the NCD region. The standardised rapid assessment of avoidable blindness (RAAB) with diabetic retinopathy (+DR) methodology was used. Blindness was defined as presenting visual acuity <3/60 in the better eye. Participants were classified as having diabetes if they were known to have diabetes or if their random blood glucose level was ≥200 mg/dL. Dilated fundus examination and Scottish DR grading were performed. RESULTS: In total, 1192 out of 1250 eligible participants (95.4%) were examined. Of these, 7.8% had known or newly diagnosed diabetes. Seventy-one per cent of participants with known diabetes had a blood glucose level ≥200 mg/dL, and 82.9% had never had an ophthalmological examination for DR. Prevalence of DR and/or maculopathy was 46.4%. The age-adjusted and sex-adjusted prevalence of diabetes was estimated at 8.1% (95% CI 5.7% to 10.4%) in the population aged 50 years or older in the NCD region of PNG. CONCLUSIONS: Prevalence of diabetes in adults aged 50 years and older was lower than reported elsewhere in the region, and lower than other RAAB+DR surveys. Despite this, the prevalence of DR is high compared with other RAAB+DR surveys and demonstrates the need for increased awareness and accessibility to eye services for people with diabetes.