Jonathan D. King

Mapping, monitoring, and surveillance of neglected tropical diseases: towards a policy framework

As national programmes respond to the new opportunities presented for scaling up preventive chemotherapy programmes for the coadministration of drugs to target lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminthiasis, and trachoma, possible synergies between existing disease-specific policies and protocols need to be examined. In this report we compare present policies for mapping, monitoring, and surveillance for these diseases, drawing attention to both the challenges and opportunities for integration. Although full integration of all elements of mapping, monitoring, and surveillance strategies might not be feasible for the diseases targeted through the preventive chemotherapy approach, there are opportunities for integration, and we present examples of integrated strategies. Finally, if advantage is to be taken of scaled up interventions to address neglected tropical diseases, efforts to develop rapid, inexpensive, and easy-to-use methods, whether disease-specific or integrated, should be increased. We present a framework for development of an integrated monitoring and evaluation system that combines both integrated and disease-specific strategies.

The Global Trachoma Mapping Project: Methodology of a 34-Country Population-Based Study

ABSTRACT Purpose: To complete the baseline trachoma map worldwide by conducting population-based surveys in an estimated 1238 suspected endemic districts of 34 countries. Methods: A series of national and sub-national projects owned, managed and staffed by ministries of health, conduct house-to-house cluster random sample surveys in evaluation units, which generally correspond to “health district” size: populations of 100,000–250,000 people. In each evaluation unit, we invite all residents aged 1 year and older from h households in each of c clusters to be examined for clinical signs of trachoma, where h is the number of households that can be seen by 1 team in 1 day, and the product h × c is calculated to facilitate recruitment of 1019 children aged 1–9 years. In addition to individual-level demographic and clinical data, household-level water, sanitation and hygiene data are entered into the purpose-built LINKS application on Android smartphones, transmitted to the Cloud, and cleaned, analyzed and ministry-of-health-approved via a secure web-based portal. The main outcome measures are the evaluation unit-level prevalence of follicular trachoma in children aged 1–9 years, prevalence of trachomatous trichiasis in adults aged 15 + years, percentage of households using safe methods for disposal of human feces, and percentage of households with proximate access to water for personal hygiene purposes. Results: In the first year of fieldwork, 347 field teams commenced work in 21 projects in 7 countries. Conclusion: With an approach that is innovative in design and scale, we aim to complete baseline mapping of trachoma throughout the world in 2015.

Global Programme to Eliminate Lymphatic Filariasis: The Processes Underlying Programme Success

Lymphatic filariasis (LF) is caused by filarial worms that live in the lymphatic system and commonly lead to lymphoedema, elephantiasis, and hydrocele. LF is recognized as endemic in 73 countries and territories; an estimated 1.39 billion (thousand million) people live in areas where filariasis has been endemic and is now targeted for treatment [1]. Global momentum to eliminate LF has developed over the past 15 years as a result not only of research demonstrating the value of single-dose treatment strategies and point-of-care diagnostic tools, but also of both the generous donations of medicines from the following committed pharmaceutical companies: GlaxoSmithKline (albendazole), Merck (ivermectin), and Eisai (diethylcarbamazine; DEC), and the essential financial support for programme implementation from the donor community [2]. During 2011, more than 50 countries carried out LF elimination programmes, and more than 500 million people received mass treatment [1]. A principal reason for the programmes dramatic expansion and success to date has been the galvanizing of efforts of all key partners around a common policy framework created and coordinated through the World Health Organizations Global Programme to Eliminate Lymphatic Filariasis (GPELF). This report, rather than highlighting the very considerable contributions of each individual partner or even chronicling most of the specific achievements of the GPELF, instead focuses on the details of the underlying processes themselves and their importance in determining programme success.

A novel electronic data collection system for large-scale surveys of neglected tropical diseases.

Background Large cross-sectional household surveys are common for measuring indicators of neglected tropical disease control programs. As an alternative to standard paper-based data collection, we utilized novel paperless technology to collect data electronically from over 12,000 households in Ethiopia. Methodology We conducted a needs assessment to design an Android-based electronic data collection and management system. We then evaluated the system by reporting results of a pilot trial and from comparisons of two, large-scale surveys; one with traditional paper questionnaires and the other with tablet computers, including accuracy, person-time days, and costs incurred. Principle Findings The electronic data collection system met core functions in household surveys and overcame constraints identified in the needs assessment. Pilot data recorders took 264 (standard deviation (SD) 152 sec) and 260 sec (SD 122 sec) per person registered to complete household surveys using paper and tablets, respectively (P = 0.77). Data recorders felt a lack of connection with the interviewee during the first days using electronic devices, but preferred to collect data electronically in future surveys. Electronic data collection saved time by giving results immediately, obviating the need for double data entry and cross-correcting. The proportion of identified data entry errors in disease classification did not differ between the two data collection methods. Geographic coordinates collected using the tablets were more accurate than coordinates transcribed on a paper form. Costs of the equipment required for electronic data collection was approximately the same cost incurred for data entry of questionnaires, whereas repeated use of the electronic equipment may increase cost savings. Conclusions/Significance Conducting a needs assessment and pilot testing allowed the design to specifically match the functionality required for surveys. Electronic data collection using an Android-based technology was suitable for a large-scale health survey, saved time, provided more accurate geo-coordinates, and was preferred by recorders over standard paper-based questionnaires.

Intestinal parasite prevalence in an area of ethiopia after implementing the SAFE strategy, enhanced outreach services, and health extension program.

Background The SAFE strategy aims to reduce transmission of Chlamydia trachomatis through antibiotics, improved hygiene, and sanitation. We integrated assessment of intestinal parasites into large-scale trachoma impact surveys to determine whether documented environmental improvements promoted by a trachoma program had collateral impact on intestinal parasites. Methodology We surveyed 99 communities for both trachoma and intestinal parasites (soil-transmitted helminths, Schistosoma mansoni, and intestinal protozoa) in South Gondar, Ethiopia. One child aged 2–15 years per household was randomly selected to provide a stool sample of which about 1 g was fixed in sodium acetate-acetic acid-formalin, concentrated with ether, and examined under a microscope by experienced laboratory technicians. Principal Findings A total of 2,338 stool specimens were provided, processed, and linked to survey data from 2,657 randomly selected children (88% response). The zonal-level prevalence of Ascaris lumbricoides, hookworm, and Trichuris trichiura was 9.9% (95% confidence interval (CI) 7.2–12.7%), 9.7% (5.9–13.4%), and 2.6% (1.6–3.7%), respectively. The prevalence of S. mansoni was 2.9% (95% CI 0.2–5.5%) but infection was highly focal (range by community from 0–52.4%). The prevalence of any of these helminth infections was 24.2% (95% CI 17.6–30.9%) compared to 48.5% as found in a previous study in 1995 using the Kato-Katz technique. The pathogenic intestinal protozoa Giardia intestinalis and Entamoeba histolytica/E. dispar were found in 23.0% (95% CI 20.3–25.6%) and 11.1% (95% CI 8.9–13.2%) of the surveyed children, respectively. We found statistically significant increases in household latrine ownership, use of an improved water source, access to water, and face washing behavior over the past 7 years. Conclusions Improvements in hygiene and sanitation promoted both by the SAFE strategy for trachoma and health extension program combined with preventive chemotherapy during enhanced outreach services are plausible explanations for the changing patterns of intestinal parasite prevalence. The extent of intestinal protozoa infections suggests poor water quality or unsanitary water collection and storage practices and warrants targeted intervention.

The excess burden of trachomatous trichiasis in women: A systematic review and meta-analysis

It is widely accepted that women carry an increased burden of trachomatous trichiasis compared with men, but there is no systematic review of the available prevalence surveys in the peer-reviewed literature. A literature search was conducted to identify population-based trachoma prevalence surveys utilising the WHO simplified grading system that included data for trichiasis. Of 53 identified studies, 24 studies from 12 different countries met the inclusion criteria. Prevalence data were pooled in a meta-analysis to estimate an overall odds ratio (OR). The overall odds of trichiasis in women compared with men was 1.82 (95% CI 1.61-2.07). Individual survey ORs ranged from 0.83 (95% CI 0.40-1.73) in Myanmar to 3.82 (95% CI 2.36-6.19) in Ethiopia. There were statistically significant differences in odds of trichiasis by gender in 17 of 24 studies, all of which showed increased odds of trichiasis in women compared with men. These data confirm the perception that women have a greater burden of trichiasis, and this burden persists across all populations studied. Women must be specifically and deliberately targeted for trichiasis surgery if the aim of eliminating blindness from trachoma is to be achieved.

Evaluation of three years of the SAFE strategy (Surgery, Antibiotics, Facial cleanliness and Environmental improvement) for trachoma control in five districts of Ethiopia hyperendemic for trachoma:

Trachoma surveys were conducted at baseline in five districts of Amhara National Regional State, Ethiopia (7478 participants in 1096 households) and at 3-year evaluation (5762 participants in 1117 households). Uptake of SAFE was assessed with programme monitoring data and interviews, and children (1-6 years) were swabbed for detection of ocular Chlamydia. At evaluation, 23,933 people had received trichiasis surgery; 93% of participants reported taking azithromycin at least once; 67% of household respondents (range 46-93) reported participation in trachoma health education; and household latrine coverage increased from 2% to 34%. In children aged 1-9 years percentage decline, by district, for outcomes was: 32% (95% CI 19-48) to 88% (95% CI 83-91) for trachomatous inflammation-follicular (TF); 87% (95% CI 83-91) to 99% (95% CI 97-100) for trachomatous inflammation-intense (TI); and 31% increase (95% CI -42 to -19) to 89% decrease (95% CI 85-93) for unclean face; and in adults percentage decline in trichiasis was 45% (95% CI -13 to 78) to 92% (95% CI 78-96). Overall prevalence of swabs positive for ocular Chlamydia was 3.1%. Although there were substantial reductions in outcomes in children and adults, the presence of ocular Chlamydia and TF in children suggests ongoing transmission. Continued implementation of SAFE is warranted.

The burden of trachoma in Ayod County of Southern Sudan.

Background Blindness due to trachoma is avoidable through Surgery, Antibiotics, Facial hygiene and Environmental improvements (SAFE). Recent surveys have shown trachoma to be a serious cause of blindness in Southern Sudan. We conducted this survey in Ayod County of Jonglei State to estimate the need for intervention activities to eliminate blinding trachoma. Methodology and Findings A cross-sectional two-stage cluster random survey was conducted in November 2006. All residents of selected households were clinically assessed for trachoma using the World Health Organization (WHO) simplified grading scheme. A total of 2,335 people from 392 households were examined, of whom 1,107 were over 14 years of age. Prevalence of signs of active trachoma in children 1–9 years of age was: trachomatous inflammation follicular (TF) = 80.1% (95% confidence interval [CI], 73.9–86.3); trachomatous inflammation intense (TI) = 60.7% (95% CI, 54.6–66.8); and TF and/or TI (active trachoma) = 88.3% (95% CI, 83.7–92.9). Prevalence of trachomatous trichiasis (TT) was 14.6% (95% CI, 10.9–18.3) in adults over 14 years of age; 2.9% (95% CI, 0.4–5.3) in children 1–14 years of age; and 8.4% (95% CI, 5.5–11.3) overall. The prevalence of corneal opacity in persons over 14 years of age with TT was 6.4% (95% CI, 4.5–8.3). No statistically significant difference was observed in the prevalence of trachoma signs between genders. Trachoma affected almost all households surveyed: 384/392 (98.0%) had at least one person with active trachoma and 130 (33.2%) had at least one person with trichiasis. Conclusions Trachoma is an unnecessary public health problem in Ayod. The high prevalence of active trachoma and trichiasis confirms the severe burden of blinding trachoma found in other post-conflict areas of Southern Sudan. Based on WHO recommended thresholds, all aspects of the SAFE strategy are indicated to eliminate blinding trachoma in Ayod.

Achieving trachoma control in Ghana after implementing the SAFE strategy

The Ghana Health Service plans to eliminate blinding trachoma by 2010 and has implemented the SAFE strategy since 2001. The programme impact was assessed in all endemic districts. A two-stage, cluster random sample of 720 households was selected in each of 18 endemic districts in Upper West and Northern Regions. All eligible residents were examined for trachoma signs. Household environmental risk factors were assessed. In total, 74,225 persons from 12,679 households were examined. Prevalence of trachomatous inflammation-follicular in 1-9 year-old children was 0.84% (95% CI 0.63-1.05, range of point estimates by district 0.14-2.81%) and prevalence of trichiasis in adults aged > or = 15 years was 0.31% (95% CI 0.24-0.38, range by district 0.00-1.07%). An estimated 4950 persons have trichiasis, of whom 72.6% are aged > or = 60 years and 71.4% are women. Latrines were observed in 11.6% of households and 79.2% of interview respondents reported use of an improved water source. Active trachoma is no longer a public health problem in Ghana after successful implementation of the SAFE strategy. The programme should maintain health education, advocate for improved water and sanitation and focus on providing surgery. Surveillance activities are needed to ensure sustained control.

Blinding Trachoma in Katsina State, Nigeria: Population-Based Prevalence Survey in Ten Local Government Areas

Purpose: To assess the prevalence of trachomatous inflammation follicular (TF) in children aged 1–9 years and trachomatous trichiasis (TT) in adults aged 15 years or more in Katsina State, Nigeria. Methods: Cross sectional population-based trachoma prevalence surveys were conducted using multistage cluster random sampling methodology and the WHO simplified grading system for trachoma in ten local government areas (LGAs). Individual and household risk factors were recorded using a standard questionnaire. Results: A total of 11,407 children and 8,901 adults from 2,244 households were surveyed. Prevalence of TF in children aged 1–9 years ranged from 5.0 to 24.0%. Five LGAs exceeded the 10% threshold for intervention and a further three exceeded 10% in the 95% confidence limits. The prevalence of TT in adults aged 15 years or more ranged from 2.3 to 8.0%: all ten LGAs exceeded the 1% intervention threshold. Analysis of risk factors for active trachoma (TF and/or TI) in children showed the following significant independent associations: Presence of ocular discharge OR = 2.34 (95%CI 1.81–3.03); presence of nasal discharge OR = 1.44 (1.22–1.70); reported frequency of face washing once versus at least twice per day OR = 1.27 (1.02–1.58); disposal of trash inside the compound OR = 1.23 (1.02–1.48); and the absence of a household latrine OR = 1.43 (1.15–1.78). Conclusions: A trachoma control program is warranted in Katsina. Surgical interventions to correct TT are needed immediately in all LGAs surveyed and the full SAFE strategy is justified for five of the ten LGAs, and possibly for another three.