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.

Completing Baseline Mapping of Trachoma in Uganda: Results of 14 Population-Based Prevalence Surveys Conducted in 2014 and 2018.

PURPOSE: We aimed to estimate the prevalence of trachomatous inflammation-follicular (TF) in children aged 1-9 years, trichiasis in adults aged ≥15 years, and water and sanitation (WASH) indicators in 12 suspected-endemic districts in Uganda. METHODS: Surveys were undertaken in 14 evaluation units (EUs) covering 12 districts. Districts were selected based on a desk review in 2014 (four districts) and trachoma rapid assessments in 2018 (eight districts). We calculated that 1,019 children aged 1-9 years were needed in each EU to estimate TF prevalence with acceptable precision and used three-stage cluster sampling to select 30 households in each of 28 (2014 surveys) or 24 (2018 surveys) villages. Participants living in selected households aged ≥1 year were examined for trachoma; thus enabling estimation of prevalences of TF in 1-9 year-olds and trichiasis in ≥15 year-olds. Household-level WASH access data were also collected. RESULTS: A total of 11,796 households were surveyed; 22,465 children aged 1-9 years and 24,652 people aged ≥15 years were examined. EU-level prevalence of TF ranged from 0.3% (95% confidence interval [CI] 0.1-0.7) to 3.9% (95% CI 2.1-5.8). EU-level trichiasis prevalence ranged from 0.01% (95% CI 0-0.11) to 0.81% (95% CI 0.35-1.50). Overall proportions of households with improved drinking water source, water source in yard or within 1km, and improved sanitation facilities were 88.1%, 23.0% and 23.9%, respectively. CONCLUSION: TF was not a public health problem in any of the 14 EUs surveyed: antibiotic mass drug administration is not required in these districts. However, in four EUs, trichiasis prevalence was ≥ 0.2%, so public health-level trichiasis surgery interventions are warranted. These findings will facilitate planning for elimination of trachoma in Uganda.

Transmission of Onchocerca volvulus by Simulium neavei in Mount Elgon focus of Eastern Uganda has been interrupted.

The study determined that Simulium neavei-transmitted onchocerciasis in Mount Elgon onchocerciasis focus had been interrupted. Annual mass treatment with ivermectin changed to two times per year along with vector elimination in 2007. Then, baseline microfilaria (mf) prevalence data of 1994 in five sentinel communities were compared with follow-up data in 2005 and 2011. Blood spots from 3,051 children obtained in 2009 were analyzed for Onchocerca volvulus immunoglobulin G4 antibodies. Fresh water crab host captures and blackflies collected indicated their infestation with larval stages of S. neavei and presence or absence of the vector, respectively. Mf rates dropped from 62.2% to 0.5%, and 1 (0.03%) of 3,051 children was positive for O. volvulus antibodies. Crab infestation dropped from 41.9% in 2007 to 0%, and S. neavei biting reduced to zero. Both remained zero for the next 3 years, confirming interruption of onchocerciasis transmission, and interventions were halted.

Transmission of Onchocerca volvulus continues in Nyagak-Bondo focus of northwestern Uganda after 18 years of a single dose of annual treatment with ivermectin.

The objective of the study was to determine whether annual ivermectin treatment in the Nyagak-Bondo onchocerciasis focus could safely be withdrawn. Baseline skin snip microfilariae (mf) and nodule prevalence data from six communities were compared with data collected in the 2011 follow-up in seven communities. Follow-up mf data in 607 adults and 145 children were compared with baseline (300 adults and 58 children). Flies collected in 2011 were dissected, and poolscreen analysis was applied to ascertain transmission. Nodule prevalence in adults dropped from 81.7% to 11.0% (P < 0.0001), and mf prevalence dropped from 97.0% to 23.2% (P < 0.0001). In children, mf prevalence decreased from 79.3% to 14.1% (P < 0.0001). Parous and infection rates of 401 flies that were dissected were 52.9% and 1.5%, respectively, whereas the infective rate on flies examination by polymerase chain reaction (PCR) was 1.92% and annual transmission potential was 26.9. Stopping ivermectin treatment may result in onchocerciasis recrudescence.

Transmission of onchocerciasis in wadelai focus of northwestern Uganda has been interrupted and the disease eliminated.

Wadelai, an isolated focus for onchocerciasis in northwest Uganda, was selected for piloting an onchocerciasis elimination strategy that was ultimately the precursor for countrywide onchocerciasis elimination policy. The Wadelai focus strategy was to increase ivermectin treatments from annual to semiannual frequency and expand geographic area in order to include communities with nodule rate of less than 20%. These communities had not been covered by the previous policy that sought to control onchocerciasis only as a public health problem. From 2006 to 2010, Wadelai program successfully attained ultimate treatment goal (UTG), treatment coverage of ≥90%, despite expanding from 19 to 34 communities and from 5,600 annual treatments to over 29,000 semiannual treatments. Evaluations in 2009 showed no microfilaria in skin snips of over 500 persons examined, and only 1 of 3011 children was IgG4 antibody positive to the OV16 recombinant antigen. No Simulium vectors were found, and their disappearance could have sped up interruption of transmission. Although twice-per-year treatment had an unclear role in interruption of transmission, the experience demonstrated that twice-per-year treatment is feasible in the Ugandan setting. The monitoring data support the conclusion that onchocerciasis has been eliminated from the Wadelai focus of Uganda.

Traditional kinship system enhanced classic community-directed treatment with ivermectin (CDTI) for onchocerciasis control in Uganda.

The challenges of community-directed treatment with ivermectin (CDTI) for onchocerciasis control in Africa have been: maintaining a desired treatment coverage, demand for monetary incentives, high attrition of community distributors and low involvement of women. This study assessed how challenges could be minimised and performance improved using existing traditional kinship structures. In classic CDTI areas, community members decide upon selection criteria for community distributors, centers for health education and training, and methods of distributing ivermectin. In kinship enhanced CDTI, similar procedures were followed at the kinship level. We compared 14 randomly selected kinship enhanced CDTI communities with 25 classic CDTI communities through interviews of 447 and 750 household members and 127 and 64 community distributors respectively. Household respondents from kinship enhanced CDTI reported better performance (P<0.001) than classic CDTI on the following measures of program effectiveness: (a) treatment coverage (b) decision on treatment location and (c) mobilization for CDTI activities. There were more female distributors in kinship enhanced CDTI than in classic CDTI. Attrition was not a problem. Kinship enhanced CDTI had a higher number of community distributors per population working among relatives, and were more likely to be involved in additional health care activities. The results suggest that kinship enhanced CDTI was more effective than classic CDTI.

Monitoring ivermectin distributors involved in integrated health care services through community-directed interventions--a comparison of Cameroon and Uganda experiences over a period of three years (2004-2006).

OBJECTIVES: To assess and compare the effectiveness of ivermectin distributors in attaining 90% treatment coverage of the eligible population with each additional health activity they take up. METHODS: Random sampling was applied every year to select distributors for interviews in community-directed treatment with ivermectin (CDTI) areas of Cameroon and Uganda. A total of 288 in 2004, 357 in 2005 and 348 in 2006 distributors were interviewed in Cameroon, and 706, 618 and 789 in Uganda, respectively. The questions included treatment coverage, involvement in additional activities, where and for how long these activities were provided, and whether they were supervised. RESULTS: At least 70% of the distributors in Cameroon and Uganda during the study period were involved in CDTI and additional health activities. More of the distributors involved in CDTI alone attained 90% treatment coverage than those who had CDTI with additional health activities. The more the additional activities, the less likely the distributors were to attain 90% treatment coverage. In Uganda, distributors were more likely to attain 90% coverage (P < 0.001 if they worked within 1 km of their homesteads were selected by community members, worked among kindred, and were responsible for <20 households. CONCLUSION: Additional activities could potentially undermine the performance of distributors. However, being selected by their community members, working largely among kindred and serving fewer households improved their effectiveness.

Involvement and performance of women in community-directed treatment with ivermectin for onchocerciasis control in Rukungiri District, Uganda.

The present study aimed: (1) to assess and improve the level of women's involvement in a strategy to control onchocerciasis by community-directed treatment with ivermectin (CDTI) in three parishes of Rukungiri District, Uganda; (2) to measure the performance of female community-directed health workers (CDHWs) in comparison with males; and (3) to identify culturally acceptable means of enhancing women's involvement in community-directed healthcare. Health education sessions were used to instruct community members to select female CDHWs in Masya Parish and to stress their potential importance in Karangara Parish; this subject was not raised in Mukono Parish. In all, 403 mature women who were randomly selected from the three parishes were interviewed as to their: (1) knowledge of the classes of people not eligible to take ivermectin; (2) knowledge and beliefs about the benefits of ivermectin; (3) participation in decision-making; and (4) attitudes on the performance of female CDHWs. For analysis, the respondees were divided into: (1) those who had or had not taken ivermectin treatment during the previous year; and (2) those who had or had not attended health education sessions. During the period when face-to-face interviews with women in randomly selected households were being carried out, participatory evaluation meetings (PEMs) were conducted in selected communities from the same parishes in order to reach a consensus on issues which could not easily be included in individual face-to-face interviews. Participant observations were also made regarding: how communities selected their CDHWs; how the CDHWs organised the distribution exercise and treated community members; and how the CDHWs kept records in order to understand issues which were deliberately hidden from the researchers during face-to-face interviews and PEMs. Significantly, the women who had been treated or health educated in Masya Parish were: (1) more knowledgeable on the groups which were not supposed to be treated; (2) aware of women's involvement in mobilisation of other community members; (3) involved in CDTI decision-making; and (4) had a better attitude towards female CDHWs' performance compared with males when compared with those from Karangara and Mukono parishes. There were no differences between the attitude of women in Karangara and Mukono parishes towards performance of female CDHWs. Face-to-face interviews and records from all parishes indicated that female CDHWs achieved as good a coverage as their male counterparts, and sometimes better, in about the same time. Health education increased the number of female CDHWs from nine to 52 in Masya Parish, from 7 to 22 in Karangara Parish and from 6 to 20 in Mukono Parish. Health education improved the attitude of women towards female CDHWs, but the actual experience of having and observing female CDHWs in action in Masya Parish had a more significant positive impact on the womenfolk, as well as on the rest of the community members, and created an impetus for more of them to become actively involved in actual ivermectin distribution. The present authors conclude that recruiting more female CDHWs and supervisors would reduce the current male domination of the health delivery services, greatly strengthening the activities of CDTI programmes.