Impact of personal protective equipment on the clarity of vision among trachoma survey graders and trichiasis surgeons in the context of COVID-19.

BACKGROUND/AIMS: The COVID-19 pandemic necessitated the use of personal protective equipment for those involved in trachoma survey grading and trichiasis surgery. We sought to determine which configuration of a face shield would be less likely to impact grading accuracy and ability to conduct trichiasis surgery. The research also included assessment of comfort, ease of cleaning and robustness. METHODS: There were three research phases. In phase 1, assessment of four potential face shield configurations was undertaken with principal trachoma graders and trichiasis surgeon trainers to decide which two options should undergo further testing. In phase 2, clarity of vision and comfort (in a classroom environment) of the two configurations were assessed compared with no face shield (control), while grading trachomatous inflammation-follicular (TF). The second phase also included the assessment of impact of the configurations while performing trichiasis surgery using a training model. In phase 3, face shield ease of use was evaluated during routine surgical programmes. RESULTS: In phase 2, 124 trachoma graders and 28 trichiasis surgeons evaluated the 2 face shield configurations selected in phase 1. TF agreement was high (kappa=0.83 and 0.82) for both configurations compared with not wearing a face shield. Comfort was reported as good by 51% and 32% of graders using the two configurations. Trichiasis skill scores were similar for both configurations. CONCLUSION: The face shield configuration that includes a cut-out for mounting the 2.5× magnifying loupes does not appear to impact the ability or comfort of trachoma graders or trichiasis surgeons to carry out their work.

Baseline Prevalence of Trachoma in Refugee Settlements in Uganda: Results of 11 Population-based Surveys.

PURPOSE: There are several settlements in the Northern and Western Regions of Uganda serving refugees from South Sudan and Democratic Republic of Congo (DRC), respectively. Trachoma prevalence surveys were conducted in a number of those settlements with the aim of determining whether interventions for trachoma are required. METHODS: An evaluation unit (EU) was defined as all refugee settlements in one district. Cross-sectional population-based trachoma prevalence survey methodologies designed to adhere to World Health Organization recommendations were deployed in 11 EUs to assess prevalence of trachomatous inflammation-follicular (TF) in 1-9-year-olds and trachomatous trichiasis (TT) unknown to the health system in ≥15-year-olds. Household-level water, sanitation and hygiene coverage was also assessed in study populations. RESULTS: A total of 40,892 people were examined across 11 EUs between 2018 and 2020. The prevalence of TF in 1-9-year-olds was <5% in all EUs surveyed. The prevalence of trachomatous trichiasis (TT) unknown to the health system in ≥15-year-olds was <0.2% in 5 out of 11 EUs surveyed and ≥0.2% in the remaining 6 EUs. A high proportion of households had improved water sources, but a low proportion had improved latrines or quickly (within a 30-minute return journey) accessible water sources. CONCLUSIONS: Implementation of the antibiotic, facial cleanliness and environmental improvement components of the SAFE strategy is not needed for the purposes of trachoma's elimination as a public health problem in these refugee settlements; however, intervention with TT surgery is needed in six EUs. Since instability continues to drive displacement of people from South Sudan and DRC into Uganda, there is likely to be a high rate of new arrivals to the settlements over the coming years. These populations may therefore have trachoma surveillance needs that are distinct from the surrounding non-refugee communities.

Evaluating Precision of a Trachomatous Trichiasis (TT) Super Survey with Modulating Sample Sizes in Tanzania.

As trachoma programs move towards eliminating trachoma as a public health problem, the number of surveys necessary to evaluate the status of trachomatous trichiasis (TT) increases. Currently, the World Health Organization endorses a district-level population-based prevalence survey for trachoma that involves a two-stage cluster design. We explored the validity of implementing this survey design in larger geographic areas to gain cost efficiencies. We evaluated the change in precision due to combining geographically contiguous and homogenous districts into single evaluation units (EUs) and modulating the sample size by running simulations on existing datasets. Preliminary findings from two opportunities in Tanzania show variability in the appropriateness in conducting this survey across larger geographies. These preliminary findings stress the importance of determining what is meant by homogeneity in terms of TT before combining multiple districts into a single EU.

The Importance of Failure: How Doing Impact Surveys That Fail Saves Trachoma Programs Money.

Trachoma programs use annual antibiotic mass drug administration (MDA) in evaluation units (EUs) that generally encompass 100,000-250,000 people. After one, three, or five MDA rounds, programs undertake impact surveys. Where impact survey prevalence of trachomatous inflammation-follicular (TF) in 1- to 9-year-olds is ≥ 5%, ≥ 1 additional MDA rounds are recommended before resurvey. Impact survey costs, and the proportion of impact surveys returning TF prevalence ≥ 5% (the failure rate or, less pejoratively, the MDA continuation rate), therefore influence the cost of eliminating trachoma. We modeled, for illustrative EU sizes, the financial cost of undertaking MDA with and without conducting impact surveys. As an example, we retrospectively assessed how conducting impact surveys affected costs in the United Republic of Tanzania for 2017-2018. For EUs containing 100,000 people, the median (interquartile range) cost of continuing MDA without doing impact surveys is USD 28,957 (17,581-36,197) per EU per year, whereas continuing MDA solely where indicated by impact survey results costs USD 17,564 (12,158-21,694). If the mean EU population is 100,000, then continuing MDA without impact surveys becomes advantageous in financial cost terms only when the continuation rate exceeds 71%. For the United Republic of Tanzania in 2017-2018, doing impact surveys saved enough money to provide MDA for > 1,000,000 people. Although trachoma impact surveys have a nontrivial cost, they generally save money, providing EUs have > 50,000 inhabitants, the continuation rate is not excessive, and they generate reliable data. If all EUs pass their impact surveys, then we have waited too long to do them.

The costs of monitoring trachoma elimination: Impact, surveillance, and trachomatous trichiasis (TT)-only surveys.

BACKGROUND: Although trachoma causes more cases of preventable blindness than any other infectious disease, a combination of strategies is reducing its global prevalence. As a district moves toward eliminating trachoma as a public health problem, national programs conduct trachoma impact surveys (TIS) to assess whether to stop preventative interventions and trachoma surveillance surveys (TSS) to determine whether the prevalence of active trachoma has rebounded after interventions have halted. In some contexts, programs also conduct trachomatous trichiasis (TT)-only surveys. A few costing studies of trachoma prevalence surveys exist, but none examine TIS, TSS, or TT-only surveys. METHODOLOGY/PRINCIPAL FINDINGS: We assessed the incremental financial cost to the national program of TIS, TSS, and TT-only surveys, which are standardized cluster-sampled prevalence surveys. We conducted a retrospective review of expenditures and grant disbursements for TIS and TSS in 322 evaluation units in 11 countries between 2011 and 2018. We also assessed the costs of three pilot and five standard TT-only surveys in four countries between 2017 and 2018. The median cost of TIS and TSS was $8,298 per evaluation unit [interquartile range (IQR): $6,532-$10,111, 2017 USD]. Based on a linear regression with bootstrapped confidence intervals, after controlling for country, costs per survey did not change significantly over time but did decline by $83 per survey implemented in a single round (95% CI: -$108 --$63). Of total costs, 80% went to survey fieldwork; of that, 58% went towards per diems and 38% towards travel. TT-only surveys cost a median of $9,707 (IQR: $8,537-$11,635); within a given country, they cost slightly more (106% [IQR: 94%-136%]) than TIS and TSS. CONCLUSIONS/SIGNIFICANCE: The World Health Organization requires trachoma prevalence estimates for validating the elimination of trachoma as a public health problem. This study will help programs improve their planning as they assemble resources for that effort.

Trachoma in Viet Nam: results of 11 surveillance surveys conducted with the Global Trachoma Mapping Project.

PURPOSE: Following interventions against trachoma in Viet Nam, impact surveys conducted in 2003-2011 suggested that trachoma was no longer a public health problem. In 2014, we undertook surveillance surveys to estimate prevalence of trachomatous inflammation-follicular (TF) and trichiasis. METHODS: A population-based prevalence survey was undertaken in 11 evaluation units (EUs) encompassing 24 districts, using Global Trachoma Mapping Project methods. A two-stage cluster sampling design was used in each EU, whereby 20 clusters and 60 children per cluster were sampled. Consenting eligible participants (children aged 1-9 years and adults aged ≥50 years) were examined for trachoma. RESULTS: A total of 9391 households were surveyed, and 20,185 participants (98.8% of those enumerated) were examined for trachoma. EU-level TF prevalence in 1-9-year-olds ranged from 0% to 1.6%. In one cluster (in Hà Giang Province), the percentage of children with TF was 10.3%. The overall pattern of cluster-level percentages of children with TF, however, was consistent with an exponential distribution, which would be consistent with trachoma disappearing. Among people aged ≥50 years, prevalence of trichiasis by EU ranged from 0% to 0.75%; these estimates are equivalent to 0-0.13% in all ages. The prevalence of trichiasis unknown to the health system among people aged ≥50 years, by EU, ranged from 0% to 0.17%, which is equivalent to 0-0.03% in all ages. CONCLUSION: Findings suggest that trachoma is no longer a public health problem in any of the 11 EUs surveyed. However, given the high proportion of children with TF in one cluster in Hà Giang Province, further investigations will be undertaken.

Completing Baseline Mapping of Trachoma in Nepal: Results of 27 Population-Based Prevalence Surveys Conducted in 2013 and 2014.

PURPOSE: Trachoma is endemic in parts of Nepal; implementation of the surgery, antibiotics, facial cleanliness, environmental improvement (SAFE) strategy started in 2002. Some suspected-endemic districts had not previously been mapped. We aimed to estimate the prevalences of trachomatous inflammation-follicular (TF) and trichiasis in those districts. METHODS: Population-based prevalence surveys were undertaken in 27 districts. In each of those districts, two-stage cluster sampling was used to select a sample of 2000 children aged 1-9 years and 4000 adults aged ≥15 years from a total of 40 wards (clusters), drawn evenly from two subdistricts. Consenting eligible participants were examined for trachoma by Global Trachoma Mapping Project (GTMP)-certified graders, using the World Health Organization simplified grading system. Data were analyzed at district level using GTMP methods. RESULTS: A total of 43,200 households were surveyed, and 162,094 people were examined for trachoma. District-level TF prevalence in 1-9-year-olds ranged from 0% to 4.3% (95% confidence interval [CI] 2.4-6.2). Among adults aged ≥15 years, trichiasis prevalence ranged from 0% to 0.33% (95% CI 0.08-0.65). CONCLUSION: TF was not a public health problem in any of the 27 districts surveyed; thus, antibiotic mass drug administration is not needed. In two districts (Dhanusa and Gorkha), trichiasis prevalence in adults aged ≥15 years was ≥0.2%; thus, further trichiasis surgery interventions at public health level are warranted to achieve elimination. These findings will facilitate planning for elimination of trachoma as a public health problem in Nepal.

Integrated Healthcare Delivery: A Qualitative Research Approach to Identifying and Harmonizing Perspectives of Integrated Neglected Tropical Disease Programs.

BACKGROUND: While some evidence supports the beneficial effects of integrating neglected tropical disease (NTD) programs to optimize coverage and reduce costs, there is minimal information regarding when or how to effectively operationalize program integration. The lack of systematic analyses of integration experiences and of integration processes may act as an impediment to achieving more effective NTD programming. We aimed to learn about the experiences of NTD stakeholders and their perceptions of integration. METHODOLOGY: We evaluated differences in the definitions, roles, perceived effectiveness, and implementation experiences of integrated NTD programs among a variety of NTD stakeholder groups, including multilateral organizations, funding partners, implementation partners, national Ministry of Health (MOH) teams, district MOH teams, volunteer rural health workers, and community members participating in NTD campaigns. Semi-structured key informant interviews were conducted. Coding of themes involved a mix of applying in-vivo open coding and a priori thematic coding from a start list. FINDINGS: In total, 41 interviews were conducted. Salient themes varied by stakeholder, however dominant themes on integration included: significant variations in definitions, differential effectiveness of specific integrated NTD activities, community member perceptions of NTD programs, the influence of funders, perceived facilitators, perceived barriers, and the effects of integration on health system strength. In general, stakeholder groups provided unique perspectives, rather than contrarian points of view, on the same topics. The stakeholders identified more advantages to integration than disadvantages, however there are a number of both unique facilitators and challenges to integration from the perspective of each stakeholder group. CONCLUSIONS: Qualitative data suggest several structural, process, and technical opportunities that could be addressed to promote more effective and efficient integrated NTD elimination programs. We highlight a set of ten recommendations that may address stakeholder concerns and perceptions regarding these key opportunities. For example, public health stakeholders should embrace a broader perspective of community-based health needs, including and beyond NTDs, and available platforms for addressing those needs.

'A living death': a qualitative assessment of quality of life among women with trichiasis in rural Niger.

BACKGROUND: Prior to blindness, trachoma is thought to profoundly affect women's abilities to lead normal lives, but supporting evidence is lacking. To better understand the effects of trichiasis, we asked women to define quality of life, how trichiasis affects this idea and their perceptions of eyelid surgery. METHODS: Operated and unoperated women were purposively selected for in-depth interviews. These were audio-recorded and transcribed, and codes were identified and applied to the transcripts. Overarching themes, commonalities and differences were identified and matched to quotations. RESULTS: Twenty-three women were interviewed. Quality of life was defined as health, security, family, social status and religious participation. Trichiasis caused severe pain and loss of health, leading to loss of security. This affected social, economic and religious activities and caused burden on their families. Surgery improved quality of life, even in cases of surgical failure or recurrent disease. CONCLUSIONS: Trichiasis disables most women, even those reporting fewer or less-severe symptoms. While women in rural Niger often live in extreme poverty, trichiasis exacerbates the situation, making women unable to work and undermining their social status. It adds to family burden, as women lose the ability to meaningfully contribute to the household and require additional family resources for their care.

Estimation of insecticide persistence, biological activity and mosquito resistance to PermaNet® 2 long-lasting insecticidal nets over three to 32 months of use in Ethiopia.

BACKGROUND: Information is needed on the expected durability of insecticidal nets under operational conditions. The persistence of insecticidal efficacy is important to estimate the median serviceable life of nets under field conditions and to plan for net replacement. METHODS: Deltamethrin residue levels were evaluated by the proxy method of X-ray fluorescence spectrometry on 189 nets used for three to six months from nine sites, 220 nets used for 14-20 months from 11 sites, and 200 nets used for 26-32 months from ten sites in Ethiopia. A random sample of 16.5-20% of nets from each time period (total 112 of 609 nets) were tested by bioassay with susceptible mosquitoes, and nets used for 14-20 months and 26-32 months were also tested with wild caught mosquitoes. RESULTS: Mean insecticide levels estimated by X-ray fluorescence declined by 25.9% from baseline of 66.2 (SD 14.6) mg/m2 at three to six months to 44.1 (SD 21.2) mg/m2 at 14-20 months and by 30.8% to 41.1 (SD 18.9) mg/m2 at 26-32 months. More than 95% of nets retained greater than 10 mg/m2 of deltamethrin and over 79% had at least 25 mg/m2 at all time periods. By bioassay with susceptible Anopheles, mortality averaged 89.0% on 28 nets tested at three to six months, 93.3% on 44 nets at 14-20 months and 94.1% on 40 nets at 26-32 months. With wild caught mosquitoes, mortality averaged 85.4% (range 79.1 to 91.7%) at 14-20 months but had dropped significantly to 47.2% (39.8 to 54.7%) at 26-32 months. CONCLUSIONS: Insecticide residue level, as estimated by X-ray fluorescence, declined by about one third between three and six months and 14-20 months, but remained relatively stable and above minimum requirements thereafter up to 26-32 months. The insecticidal activity of PermaNet® 2.0 long-lasting insecticidal nets in the specified study area may be considered effective to susceptible mosquitoes at least for the duration indicated in this study (32 months). However, results indicated that resistance in the wild population is already rendering nets with optimum insecticide concentrations less effective in practice.

Prevalence of trachoma at sub-district level in ethiopia: determining when to stop mass azithromycin distribution.

BACKGROUND: To eliminate blinding trachoma, the World Health Organization emphasizes implementing the SAFE strategy, which includes annual mass drug administration (MDA) with azithromycin to the whole population of endemic districts. Prevalence surveys to assess impact at the district level are recommended after at least 3 years of intervention. The decision to stop MDA is based on a prevalence of trachomatous inflammation follicular (TF) among children aged 1-9 years below 5% at the sub-district level, as determined by an additional round of surveys limited within districts where TF prevalence is below 10%. We conducted impact surveys powered to estimate prevalence simultaneously at the sub-district and district in two zones of Amhara, Ethiopia to determine whether MDA could be stopped. METHODOLOGY: Seventy-two separate population-based, sub-district surveys were conducted in 25 districts. In each survey all residents from 10 randomly selected clusters were screened for clinical signs of trachoma. Data were weighted according to selection probabilities and adjusted for correlation due to clustering. PRINCIPAL FINDINGS: Overall, 89,735 residents were registered from 21,327 households of whom 72,452 people (80.7%) were examined. The prevalence of TF in children aged 1-9 years was below 5% in six sub-districts and two districts. Sub-district level prevalence of TF in children aged 1-9 years ranged from 0.9-76.9% and district-level from 0.9-67.0%. In only one district was the prevalence of trichiasis below 0.1%. CONCLUSIONS/SIGNIFICANCE: The experience from these zones in Ethiopia demonstrates that impact assessments designed to give a prevalence estimate of TF at sub-district level are possible, although the scale of the work was challenging. Given the assessed district-level prevalence of TF, sub-district-level surveys would have been warranted in only five districts. Interpretation was not as simple as stopping MDA in sub-districts below 5% given programmatic challenges of exempting sub-districts from a highly regarded program and the proximity of hyper-endemic sub-districts.

Trachoma prevalence in Niger: results of 31 district-level surveys.

BACKGROUND: The leading cause of preventable blindness worldwide is trachoma, a condition caused by an infection of the inner eyelid. In Niger, a landlocked republic in Western Africa, surveys in 1988-89 identified trachoma as endemic in all but one region and, as a result, there is a National Prevention of Blindness Program plan to eliminate trachoma by 2015. METHODS: Thirty-one districts in eastern and western Niger were surveyed for trachoma prevalence from May 2009 to March 2012 as part of routine program impact evaluations. Prevalence surveys were implemented independently in each district using a two-stage cluster random design. Probability proportional to size was used to randomly select villages and 25 households were selected in each cluster. The prevalence of trachoma of clinical grade trachomatous follicular (TF) was estimated in children aged 1-9 years, and the prevalence of blinding trachoma, trachomatous trichiasis (TT), was measured in adults aged ≥15 years. RESULTS: A total of 14 211 households was surveyed; 58 617 individuals were evaluated for clinical signs of trachoma, of whom 27 087 were children aged 1-9 years. District-wide implementation of the full SAFE strategy is warranted in 16 districts where TF prevalence exceeds 10% and targeted implementation of the SAFE strategy (surgery for trichiasis; antibiotic therapy to control transmission; facial cleanliness for hygiene promotion; environmental change for improvements in access to water and sanitation) is recommended in the remaining 15 districts. The prevalence of TT among adults exceeded 1% in nine districts, suggesting that surgical services to treat TT should be implemented district-wide. CONCLUSIONS: These results establish the need for continued SAFE strategy implementation throughout Niger.

Trachoma among children in community surveys from four African countries and implications of using school surveys for evaluating prevalence.

BACKGROUND: School surveys provide a convenient platform to obtain large child cohorts from multiple communities and are widely used as a proxy to determine community prevalence of neglected tropical diseases. The purpose of this study was to compare trachoma prevalence between preschool- and school-aged children and children who attend and do not attend school. METHODS: We analysed data from community-based trachoma surveys conducted from 2008-2011 in Ethiopia, Mali, Niger and Nigeria. The surveys utilised a cross-sectional, randomised cluster design. Individual-level data on school attendance was collected. RESULTS: Overall, 75 864 children aged 1-15 years from 2100 communities were included in the analysis. The prevalence of trachomatous inflammation follicular (TF) among these children in surveyed districts was 19.1% (95% CI 17.9-20.2%) in Ethiopia, 6.2% (95% CI 5.4-6.9%) in Niger, 4.6% (95% CI 4.2-4.9%) in Mali and 4.2% (95% CI 3.5-4.9%) in Nigeria. Controlling for age, sex and clustering, the OR of TF for school-attendees compared to non-attendees was 0.64 (95% CI 0.56-0.73) in Ethiopia, 0.67 (95% CI 0.56-0.80) in Mali, 1.03 (95% CI 0.81-1.16) in Niger and 1.06, (95% CI 0.65-1.73) in Nigeria. CONCLUSION: Estimating the prevalence of trachoma through examination of only school-going children risks underestimating the true prevalence.

Community-wide distribution of long-lasting insecticidal nets can halt transmission of lymphatic filariasis in southeastern Nigeria.

Lymphatic filariasis (LF) in rural southeastern Nigeria is transmitted mainly by Anopheles spp. mosquitoes. Potential coinfection with Loa loa in this area has prevented use of ivermectin in the mass drug administration (MDA) strategy for LF elimination because of potential severe adverse L. loa-related reactions. This study determined if long-lasting insecticidal net (LLIN) distribution programs for malaria would interrupt LF transmission in such areas, without need for MDA. Monthly entomologic monitoring was conducted in sentinel villages before and after LLIN distribution to all households and all age groups (full coverage) in two districts, and to pregnant women and children less than five years of age in the other two districts. No change in human LF microfilaremia prevalence was observed, but mosquito studies showed a statistically significant decrease in LF infection and infectivity with full-coverage LLIN distribution. We conclude that LF transmission can be halted in southeastern Nigeria by full-coverage LLIN distribution, without MDA.

Physical durability of PermaNet 2.0 long-lasting insecticidal nets over three to 32 months of use in Ethiopia.

BACKGROUND: Ethiopia scaled up net distribution markedly starting in 2006. Information on expected net life under field conditions (physical durability and persistence of insecticidal activity) is needed to improve planning for net replacement. Standardization of physical durability assessment methods is lacking. METHODS: Permanet®2.0 long-lasting insecticidal bed nets (LLINs), available for distribution in early 2007, were collected from households at three time intervals. The number, size and location of holes were recorded for 189 nets used for three to six months from nine sites (2007) and 220 nets used for 14 to 20 months from 11 sites (2008). In 2009, a "finger/fist" sizing method classified holes in 200 nets used for 26 to 32 months from ten sites into small (<2 cm), medium (> = 2 to < =10 cm) and large (>10 cm) sizes. A proportionate hole index based on both hole number and area was derived from these size classifications. RESULTS: After three to six months, 54.5% (95% CI 47.1-61.7%) of 189 LLINs had at least one hole 0.5 cm (in the longest axis) or larger; mean holes per net was 4.4 (SD 8.4), median was 1.0 (Inter Quartile Range [IQR] 0-5) and median size was 1 cm (IQR 1-2). At 14 to 20 months, 85.5% (95% CI 80.1-89.8%) of 220 nets had at least one hole with mean 29.1 (SD 50.1) and median 12 (IQR 3-36.5) holes per net, and median size of 1 cm (IQR 1-2). At 26 to 32 months, 92.5% of 200 nets had at least one hole with a mean of 62.2 (SD 205.4) and median of 23 (IQR 6-55.5) holes per net. The mean hole index was 24.3, 169.1 and 352.8 at the three time periods respectively. Repairs were rarely observed. The majority of holes were in the lower half of the net walls. The proportion of nets in 'poor' condition (hole index >300) increased from 0% at three to six months to 30% at 26 to 32 months. CONCLUSIONS: Net damage began quickly: more than half the nets had holes by three to six months of use, with 40% of holes being larger than 2 cm. Holes continued to accumulate until 92.5% of nets had holes by 26 to 32 months of use. An almost complete lack of repairs shows the need for promoting proper use of nets and repairs, to increase LLIN longevity. Using the hole index, almost one third of the nets were classed as unusable and ineffective after two and a half years of potential use.

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.

Monitoring of mass distribution interventions for trachoma in Plateau State, Nigeria.

Mass drug administration (MDA) with antibiotics is a key component of the SAFE strategy for trachoma control. Guidelines recommend that where MDA is warranted the whole population be targeted with 80% considered the minimum acceptable coverage. In other countries, MDA is usually conducted by salaried Ministry of Health personnel (MOH). In Plateau State, Nigeria, the existing network of volunteer Community Directed Distributors (CDD) was used for the first trachoma MDA. We conducted a population-based cluster random survey (CRS) of MDA participation to determine the true coverage and compared this to coverage reported from CDD registers. We surveyed 1,791 people from 352 randomly selected households in 24 clusters in three districts in Plateau State in January 2011, following the implementation of MDA. Households were enumerated and all individuals present were asked about MDA participation. Household heads were questioned about household-level characteristics and predictors of participation. Individual responses were compared with the CDD registers. MDA coverage was estimated as 60.3% (95% CI 47.9-73.8%) by the survey compared with 75.8% from administrative program reports. CDD registration books for comparison with responses were available in 19 of the 24 clusters; there was a match for 658/682 (96%) of verifiable responses. CDD registers did not list 481 (41.3%) of the individuals surveyed. Gender and age were not associated with individual participation. Overall MDA coverage was lower than the minimum 80% target. The observed discrepancy between the administrative coverage estimate from program reports and the CRS was largely due to identification of communities missed by the MDA and not reported in the registers. CRS for evaluation of MDA provides a useful additional monitoring tool to CDD registers. These data support modification of distributor training and MDA delivery to increase coverage in subsequent rounds of MDA.

Analysis of malaria surveillance data in Ethiopia: what can be learned from the Integrated Disease Surveillance and Response System?

BACKGROUND: Routine malaria surveillance data is useful for assessing incidence and trends over time, and in stratification for targeting of malaria control. The reporting completeness and potential bias of such data needs assessment. METHODS: Data on 17 malaria indicators were extracted from the Integrated Disease Surveillance and Response System database for July 2004 to June 2009 (Ethiopian calendar reporting years 1997 to 2001). Reporting units were standardized over time with 2007 census populations. The data were analysed to show reporting completeness, variation in risk by reporting unit, and incidence trends for malaria indicators. RESULTS: Reporting completeness, estimated as product of unit-month and health facility reporting, was over 80% until 2009, when it fell to 56% during a period of reorganization in the Ministry of Health. Nationally the average estimated annual incidence of reported total malaria for the calendar years 2005 to 2008 was 23.4 per 1000 persons, and of confirmed malaria was 7.6 per 1,000, with no clear decline in out-patient cases over the time period. Reported malaria in-patient admissions and deaths (averaging 6.4 per 10,000 and 2.3 per 100,000 per year respectively) declined threefold between 2005 and 2009, as did admissions and deaths reported as malaria with severe anaemia. Only 8 of 86 reporting units had average annual estimated incidence of confirmed malaria above 20 per 1,000 persons, while 26 units were consistently below five reported cases per 1,000 persons per year. CONCLUSION: The Integrated Disease Surveillance and Response System functioned well over the time period mid 2004 to the end of 2008. The data suggest that the scale up of interventions has had considerable impact on malaria in-patient cases and mortality, as reported from health centres and hospitals. These trends must be regarded as relative (over space and time) rather than absolute. The data can be used to stratify areas for improved targeting of control efforts to steadily reduce incidence. They also provide a baseline of incidence estimates against which to gauge future progress towards elimination. Inclusion of climate information over this time period and extension of the dataset to more years is needed to clarify the impact of control measures compared to natural cycles on malaria.

Performance of local light microscopy and the ParaScreen Pan/Pf rapid diagnostic test to detect malaria in health centers in Northwest Ethiopia.

BACKGROUND: Diagnostic tests are recommended for suspected malaria cases before treatment, but comparative performance of microscopy and rapid diagnostic tests (RDTs) at rural health centers has rarely been studied compared to independent expert microscopy. METHODS: Participants (N = 1997) with presumptive malaria were recruited from ten health centers with a range of transmission intensities in Amhara Regional State, Northwest Ethiopia during October to December 2007. Microscopy and ParaScreen Pan/Pf® RDT were done immediately by health center technicians. Blood slides were re-examined later at a central laboratory by independent expert microscopists. RESULTS: Of 1,997 febrile patients, 475 (23.8%) were positive by expert microscopists, with 57.7% P. falciparum, 24.6% P. vivax and 17.7% mixed infections. Sensitivity of health center microscopists for any malaria species was >90% in five health centers (four of which had the highest prevalence), >70% in nine centers and 44% in one site with lowest prevalence. Specificity for health center microscopy was very good (>95%) in all centers. For ParaScreen RDT, sensitivity was ≥90% in three centers, ≥70% in six and <60% in four centers. Specificity was ≥90% in all centers except one where it was 85%. CONCLUSIONS: Health center microscopists performed well in nine of the ten health centers; while for ParaScreen RDT they performed well in only six centers. Overall the accuracy of local microscopy exceeded that of RDT for all outcomes. This study supports the introduction of RDTs only if accompanied by appropriate training, frequent supervision and quality control at all levels. Deficiencies in RDT use at some health centers must be rectified before universal replacement of good routine microscopy with RDTs. Maintenance and strengthening of good quality microscopy remains a priority at health center level.

Lymphatic filariasis in western Ethiopia with special emphasis on prevalence of Wuchereria bancrofti antigenaemia in and around onchocerciasis endemic areas.

Lymphatic filariasis is known to be endemic in Gambella Region, western Ethiopia, but the full extent of its endemicity in other regions is unknown. A national mapping program for Ethiopia was initiated in 2008. This report summarizes initial data on the prevalence of Wuchereria bancrofti antigenaemia based on surveys carried out in a sampled population of 11685 individuals living in 125 villages (112 districts) of western Ethiopia. The overall prevalence rate was 3.7%, but high geographical clustering and variation in prevalence (ranging from 0% to more than 50%) was found. The prevalence of hydrocele (in males) and lymphoedema of limbs was 0.8% and 3.6% respectively. Significantly higher (χ(2)=49.6; P<0.01) prevalence of antigenaemia was noted in known onchocerciasis endemic districts (4.7%) compared to non-onchocerciasis endemic districts (2.3%). Thirty-four of the 112 districts, with a population of 1547685 in 2007, were found to be endemic. Of these, the numbers of districts with prevalence rates of >20%, 10-20% and 5-9% were nine, 14 and 20 respectively. Twenty-nine of these 34 endemic districts were found in three regions: Gambella Region (seven districts), Beneshangul-Gumuz Region (13 districts), and Southern Nations, Nationalities and Peoples' Region (SNNPR) (nine districts). The other five were from Amhara (two districts) and Oromia (three districts) regions. A tentative distribution map has been drawn to facilitate the launching of the Ethiopia LF elimination program.