Rounds Of MDA Research Articles

Detection of Wuchereria bancrofti DNA in wild caught vector and non-vector mosquitoes: implications for elimination of lymphatic filariasis.

Transmission Assessment Survey (TAS) is the WHO recommended method used for decision-making to stop or continue the MDA in lymphatic filariasis (LF) elimination programme. The WHO has also recommended Molecular Xenomonitoring (MX) of LF infection in vectors as an adjunct tool in settings under post-MDA or validation period. Screening of non-vectors by MX in post-MDA / validation settings could be useful to prevent a resurgence of LF infection, as there might be low abundance of vectors, especially in some seasons. In this study, we investigated the presence of LF infection in non-vectors in an area endemic for LF and has undergone many rounds of annual MDA with two drugs (Diethylcarbamazine and Albendazole, DA) and two rounds of triple drug regimens (Ivermectin + DA). Mosquitoes were collected from selected villages of Yadgir district in Karnataka state, India, during 2019. A total of 680 female mosquitoes were collected, identified morphologically by species and separated as pools. The female mosquitoes belonging to 3 species viz., Anopheles subpictus, Culex gelidus and Culex quinquefaciatus were separated, pooled, and the DNA extracted using less expensive method and followed by LDR based real-time PCR assay for detecting Wuchereria bancrofti infection in vector as well as non-vector mosquitoes. One pool out of 6 pools of An. subpictus, 2 pools out of 6 pools of Cx. gelidus, and 4 pools out of 8 pools of Cx. quinquefaciatus were found to be positive for W. bancrofti infection by RT-PCR. The infection rate in vectors and non-vectors was found to be 1.8% (95% CI: 0.5-4.2%) and 0.9% (95% CI:0.2-2.3%), respectively. Our study showed that non-vectors also harbour W. bancrofti, thus opening an opportunity of using these mosquitoes as surrogate vectors for assessing risk of transmission to humans in LF endemic and post MDA areas.

POST MASS DRUG ADMINISTRATION ASSESSMENT OF COVERAGE, COMPLIANCE, AND OBSTACLES IN A LYMPHATIC FILARIASIS ENDEMIC DISTRICT OF CENTRAL INDIA.

Introduction: Lymphatic Filariasis is still a huge problem in the endemic districts as it can cause deprivation in the economic condition of the sufferer, it is linked with stigma, and shame which leads to psychological problems in the individual. The aim was to assess the coverage, compliance, and obstacles post-Mass Drug Administration (MDA) of Filariasis in the Katni District. Methods: This community-based study was conducted in selected areas of the Katni district of Madhya Pradesh. Three rural primary health centers (PHCs) and one urban PHC were selected for the study. Afterward, 30 households were randomly selected from these 4 PHCs. The MDA drive was held in late Dec 2020 in the whole katni district. As an external evaluation, this study commenced 30 days after the drive and the data were collected. Results: A total of 128 households were surveyed, and 621 people were covered. 607 were eligible for drug administration. The overall coverage rate of MDA in the study was found to be 95.88 %. The overall effective coverage rate was 88.63 %. It was 93.93 % in urban and 86.65 % in rural areas. The overall coverage compliance gap was 7.37 %. The most common reason for the non-consumption of tablets was people busy doing work i.e., 47 %. Conclusion: It would be a challenge for the district to sustain this performance in the coming rounds of MDA. Equal Sensitization of the urban and rural populations through IEC activities and proper training for drug distributors is required.

Predisposition to soil-transmitted helminth reinfection after four rounds of mass drug administration: results from a longitudinal cohort in the Geshiyaro project, a transmission elimination feasibility study in the Wolaita zone of southern Ethiopia.

Current WHO strategies for reaching soil-transmitted helminths (STH) elimination as a public health problem excludes treating certain adult populations in endemic areas, creating infection reservoirs that drive 'bounce back' of STH infection to pretreatment levels post-mass drug administration (MDA). Predisposition is a widespread, but poorly understood phenomena among helminth infections where individuals are predisposed to reinfection after repeated treatments. This analysis uses Geshiyaro project data, an STH control programme exploring transmission interruption by community-wide MDA and enhanced water, sanitation and hygiene during 2019-2023. Parasitological survey data from longitudinal cohorts are analysed using Kendall's Tau-b rank correlation to assess the evidence for predisposition to light or heavy infection between four consecutive rounds of MDA. Correlation analyses revealed the strongest evidence for predisposition to heavy or light Ascaris lumbricoides infection was between survey 1 and 2 (Tau-b 0.29; p<0.001). Overall patterns were not observed for Trichuris trichiura or hookworm infections, however, some significant and notable correlations were recorded for some stratifications and time points. Evidence for predisposition in endemic settings in southern Ethiopia with low STH prevalence suggests that more targeted approaches to MDA in those predisposed to infection may be a sensible control strategy if cheap, point of care diagnostics are available.

Testing the effects of mass drug administration of azithromycin on mortality and other outcomes among 1–11-month-old infants in Mali (LAKANA): study protocol for a cluster-randomized, placebo-controlled, double-blinded, parallel-group, three-arm clinical trial

BackgroundMass drug administration (MDA) of azithromycin (AZI) has been shown to reduce under-5 mortality in some but not all sub-Saharan African settings. A large-scale cluster-randomized trial conducted in Malawi, Niger, and Tanzania suggested that the effect differs by country, may be stronger in infants, and may be concentrated within the first 3 months after treatment. Another study found no effect when azithromycin was given concomitantly with seasonal malaria chemoprevention (SMC). Given the observed heterogeneity and possible effect modification by other co-interventions, further trials are needed to determine the efficacy in additional settings and to determine the most effective treatment regimen.MethodsLAKANA stands for Large-scale Assessment of the Key health-promoting Activities of two New mass drug administration regimens with Azithromycin. The LAKANA trial is designed to address the mortality and health impacts of 4 or 2 annual rounds of azithromycin MDA delivered to 1–11-month-old (29–364 days) infants, in a high-mortality and malaria holoendemic Malian setting where there is a national SMC program. Participating villages (clusters) are randomly allocated in a ratio of 3:2:4 to three groups: placebo (control):4-dose AZI:2-dose AZI. The primary outcome measured is mortality. Antimicrobial resistance (AMR) will be monitored closely before, during, and after the intervention and both among those receiving and those not receiving MDA with the study drugs. Other outcomes, from a subset of villages, comprise efficacy outcomes related to morbidity, growth and nutritional status, outcomes related to the mechanism of azithromycin activity through measures of malaria parasitemia and inflammation, safety outcomes (AMR, adverse and serious adverse events), and outcomes related to the implementation of the intervention documenting feasibility, acceptability, and economic aspects. The enrolment commenced in October 2020 and is planned to be completed by the end of 2022. The expected date of study completion is December 2024.DiscussionIf LAKANA provides evidence in support of a positive mortality benefit resulting from azithromycin MDA, it will significantly contribute to the options for successfully promoting child survival in Mali, and elsewhere in sub-Saharan Africa.Trial registrationClinicalTrials.gov NCT04424511. Registered on 11 June 2020.

Impact of azithromycin mass drug administration on the antibiotic-resistant gut microbiome in children: a randomized, controlled trial

BackgroundMass drug administration (MDA) with azithromycin is the primary strategy for global trachoma control efforts. Numerous studies have reported secondary effects of MDA with azithromycin, including reductions in childhood mortality, diarrhoeal disease and malaria. Most recently, the MORDOR clinical trial demonstrated that MDA led to an overall reduction in all-cause childhood mortality in targeted communities. There is however concern about the potential of increased antimicrobial resistance in treated communities. This study evaluated the impact of azithromycin MDA on the prevalence of gastrointestinal carriage of macrolide-resistant bacteria in communities within the MORDOR Malawi study, additionally profiling changes in the gut microbiome after treatment. For faecal metagenomics, 60 children were sampled prior to treatment and 122 children after four rounds of MDA, half receiving azithromycin and half placebo.ResultsThe proportion of bacteria carrying macrolide resistance increased after azithromycin treatment. Diversity and global community structure of the gut was minimally impacted by treatment, however abundance of several species was altered by treatment. Notably, the putative human enteropathogen Escherichia albertii was more abundant after treatment.ConclusionsMDA with azithromycin increased carriage of macrolide-resistant bacteria, but had limited impact on clinically relevant bacteria. However, increased abundance of enteropathogenic Escherichia species after treatment requires further, higher resolution investigation. Future studies should focus on the number of treatments and administration schedule to ensure clinical benefits continue to outweigh costs in antimicrobial resistance carriage.Trial registration ClinicalTrial.gov, NCT02047981. Registered January 29th 2014, https://clinicaltrials.gov/ct2/show/NCT02047981

High Tregs and systemic IL-10 expressions linked to the absence of sheath antibodies in lymphatic filariasis: implications on the persistence of residual infection.

The persistence of residual infection is one of the major factors in failure of the Global Programme to Eliminate Lymphatic Filariasis (GPELF). The present study aims to explore the status of sheath antibody and regulatory T cells (Tregs) known to play key roles in clearance of parasite and patent filarial infection, in individuals with residual infection after MDA. A total of 61 microfilaremic (Mf) individuals were followed up after at least 6 rounds of MDA. Infection status of subjects was assessed through the detection of Mf and circulating filarial antigen (CFA). Antibodies to Mf sheath were determined by immuno-peroxidase assay (IPA). The expression of Tregs was measured by a flow cytometer. IL-10 and IFN-γ were evaluated using the commercially available ELISA kit. The sheath antibody was present in subjects who have cleared both Mf and CFA and absent in individuals who were found to be Mf /CFA positive. Further individuals carrying infection have significantly high levels of Tregs and IL-10. A positive correlation was observed between Tregs, IL-10, and CFA in infected individuals. In contrast, a negative correlation was observed between IFN-γ and IL-10 in both infected and uninfected subjects. Our study reveals that the absence of a sheath antibody and a high level of Tregs and IL-10 are the hallmarks of the persistence of residual filarial infection.

Heterogeneous response of Wuchereria bancrofti-infected persons to diethylcarbamazine (DEC) and its implications for the Global Programme to Eliminate Lymphatic Filariasis (GPELF).

DEC or ivermectin (IVM) in combination with albendazole (ALB) has been the recommended strategy of the Global Programme to Eliminate Lymphatic Filariasis (GPELF) since 2000. Despite effective population coverage (> 65%) with several rounds of MDA with DEC or combination of DEC plus ALB, microfilariae persist in few individuals and they continue to be the source of infection for transmitting LF. We report an individual's variability in response to DEC by defining the response as complete absence of microfilaria (mf) (post-treatment mf count = 0) and non-response as presence of mf (post-treatment mf count ≥ 1). We analyzed follow-up data on individual's response to treatment from two randomized clinical trials in which 46 microfilaremic individuals were treated with single-dose DEC (6 mg/kg body weight). They were classified into low, medium, and high mf density categories based on their pre-treatment mf counts. Of the 46 individuals, 65.2% have not responded throughout the 12-month post-treatment period. Application of a logistic regression model with fixed (age, gender, mf density, post-treatment time, and their interactions) and random (individual's response over time) effects indicated that treatment response is independent of age, gender, and time. The overall treatment response increases in low and decreases in high mf density categories. Furthermore, the estimates for the random coefficients model showed that there is a greater variability in response between individuals over post-treatment time. The results substantiate that individual variation in response to DEC exists which indicate the importance of studying the parasite as well as host genetic factors associated with DEC action.

DjinniChip: evaluation of a novel molecular rapid diagnostic device for the detection of Chlamydia trachomatis in trachoma-endemic areas

BackgroundThe clinical signs of active trachoma are often present in the absence of ocular Chlamydia trachomatis infection, particularly following mass drug administration. Treatment decisions following impact surveys and in post-control surveillance for communities are currently based on the prevalence of clinical signs, which may result in further unnecessary distribution of mass antibiotic treatment and the increased spread of macrolide resistance alleles in ‘off-target’ bacterial species. We therefore developed a simple, fast, low cost diagnostic assay (DjinniChip) for diagnosis of ocular C. trachomatis for use by trachoma control programmes.MethodsThe study was conducted in the UK, Germany and Tanzania. For clinical testing in Tanzania, specimens from a sample of 350 children between the ages of 7 to 15 years, which were part of a longitudinal cohort that began in February 2012 were selected. Two ocular swabs were taken from the right eye. The second swab was collected dry, kept cool in the field and archived at – 80 °C before sample lysis for DjinniChip detection and parallel nucleic acid purification and detection/quantification by qPCR assay.ResultsDjinniChip was able to reliably detect > 10 copies of C. trachomatis per test and correctly identified 7/10 Quality Control for Molecular Diagnostics C. trachomatis panel samples, failing to detect 3 positive samples with genome equivalent amounts ≤ 10 copies. DjinniChip performed well across a range of typical trachoma field conditions and when used by lay personnel using a series of mock samples. In the laboratory in Tanzania, using clinical samples the sensitivity and specificity of DjinniChip for C. trachomatis was 66% (95% CI 51–78) and 94.8 (95% CI 91–97%) with an overall accuracy of 90.1 (95% CI 86.4–93).ConclusionsDjinniChip performance is extremely promising, particularly its ability to detect low concentrations of C. trachomatis and its usability in field conditions. The DjinniChip requires further development to reduce inhibition and advance toward a closed system. DjinniChip results did not vary between local laboratory results and typical trachoma field settings, illustrating its potential for use in low-resource areas to prevent unnecessary rounds of MDA and to monitor for C. trachomatis recrudescence.

Mass drug administration with azithromycin for trachoma elimination and the population structure of Streptococcus pneumoniae in the nasopharynx

ObjectiveMass drug administration (MDA) with azithromycin for trachoma elimination reduces nasopharyngeal carriage of Streptococcus pneumoniae in the short term. We evaluated S. pneumoniae carried in the nasopharynx before and after a round of azithromycin MDA to determine whether MDA was associated with changes in pneumococcal population structure and resistance. MethodsWe analysed 514 pneumococcal whole genomes randomly selected from nasopharyngeal samples collected in two Gambian villages that received three annual rounds of MDA for trachoma elimination. The 514 samples represented 293 participants, of which 75% were children aged 0–9 years, isolated during three cross-sectional surveys (CSSs) conducted before the third round of MDA (CSS-1) and at 1 (CSS-2) and 6 (CSS-3) months after MDA. Bayesian Analysis of Population Structure (BAPS) was used to cluster related isolates by capturing variation in the core genome. Serotype and multilocus sequence type were inferred from the genotype. Antimicrobial resistance determinants were identified from assemblies, including known macrolide resistance genes. ResultsTwenty-seven BAPS clusters were assigned. These consisted of 81 sequence types (STs). Two BAPS clusters not observed in CSS-1 (n = 109) or CSS-2 (n = 69), increased in frequency in CSS-3 (n = 126); BAPS20 (8.73%, p 0.016) and BAPS22 (7.14%, p 0.032) but were not associated with antimicrobial resistance. Macrolide resistance within BAPS17 increased after treatment (CSS-1 n = 0/6, CSS-2/3 n = 5/5, p 0.002) and was carried on a mobile transposable element that also conferred resistance to tetracycline. DiscussionLimited changes in pneumococcal population structure were observed after the third round of MDA, suggesting treatment had little effect on the circulating lineages. An increase in macrolide resistance within one BAPS highlights the need for antimicrobial resistance surveillance in treated villages.

Impact of a single round of mass drug administration with azithromycin on active trachoma and ocular Chlamydia trachomatis prevalence and circulating strains in The Gambia and Senegal

BackgroundMass drug administration (MDA) with azithromycin is a cornerstone of the trachoma elimination strategy. Although the global prevalence of active trachoma has declined considerably, prevalence persists or even increases in some communities and districts. To increase understanding of MDA impact, we investigated the prevalence of active trachoma and ocular C. trachomatis prevalence, organism load, and circulating strains at baseline and one-year post-MDA in The Gambia and Senegal.MethodsPre- and one-year post-MDA, children aged 0–9 years were examined for clinical signs of trachoma in six Gambian and 12 Senegalese villages. Ocular swabs from each child’s right conjunctiva were tested for evidence of ocular C. trachomatis infection and organism load (ompA copy number), and ompA and multi-locus sequence typing (MLST) was performed.ResultsA total of 1171 children were examined at baseline and follow-up in The Gambia. Active trachoma prevalence decreased from 23.9% to 17.7%, whereas ocular C. trachomatis prevalence increased from 3.0% to 3.8%. In Senegal, 1613 and 1771 children were examined at baseline and follow-up, respectively. Active trachoma prevalence decreased from 14.9% to 8.0%, whereas ocular C. trachomatis prevalence increased from 1.8% to 3.6%. Higher organism load was associated with having active trachoma and severe inflammation. Sequence typing demonstrated that all Senegalese samples were genovar A, whereas Gambian samples were a mix of genovars A and B. MLST provided evidence of clustering at village and household levels and demonstrated differences of strain variant frequencies in Senegal, indicative of an “outbreak”. MLST, including partial ompA typing, provided greater discriminatory power than complete ompA typing.ConclusionsWe found that one round of MDA led to an overall decline in active trachoma prevalence but no impact on ocular C. trachomatis infection, with heterogeneity observed between villages studied. This could not be explained by MDA coverage or number of different circulating strains pre- and post-MDA. The poor correlation between active trachoma and infection prevalence supports the need for further work on alternative indicators to clinical signs for diagnosing ocular C. trachomatis infection. MLST typing has potential molecular epidemiology utility, including better understanding of transmission dynamics, although relationship to whole-genome sequence variability requires further exploration.

Impact of mass drug administration of azithromycin for trachoma elimination on prevalence and azithromycin resistance of genital Mycoplasma genitalium infection

BackgroundMass drug administration (MDA) of 20 mg/kg (maximum 1 g in adults) azithromycin for ocular Chlamydia trachomatis (CT) infection is a key component of the WHO trachoma elimination strategy. However,...

Implementing population-based mass drug administration for malaria: experience from a high transmission setting in North Eastern Uganda

BackgroundMass drug administration (MDA) is a suggested mean to accelerate efforts towards elimination and attainment of malaria-free status. There is limited evidence of suitable methods of implementing MDA programme to achieve a high coverage and compliance in low-income countries. The objective of this paper is to assess the impact of this MDA delivery strategy while using coverage measured as effective population in the community and population available.MethodsPopulation-based MDA was implemented as a part of a larger program in a high transmission setting in Uganda. Four rounds of interventions were implemented over a period of 2 years at an interval of 6 to 8 months. A housing and population census was conducted to establish the eligible population. A team of 19 personnel conducted MDA at established village meeting points as distribution sites at every village. The first dose of dihydroartemisinin–piperaquine (DHA-PQ) was administered via a fixed site distribution strategy by directly observed treatment on site, the remaining doses were taken at home and a door-to-door follow up strategy was implemented by community health workers to monitor adherence to the second and third doses.ResultsBased on number of individuals who turned up at the distribution site, for each round of MDA, effective coverage was 80.1%, 81.2%, 80.0% and 80% for the 1st, 2nd, 3rd and 4th rounds respectively. However, coverage based on available population at the time of implementing MDA was 80.1%, 83.2%, 82.4% and 82.9% for rounds 1, 2, 3 and 4, respectively. Intense community mobilization using community structures and mass media facilitated community participation and adherence to MDA.ConclusionA hybrid of fixed site distribution and door-to-door follow up strategy of MDA delivery achieved a high coverage and compliance and seemed feasible. This model can be considered in resource-limited settings.

Elimination of lymphatic filariasis as a public health problem from Tonga

BackgroundTonga was highly endemic for lymphatic filariasis (LF) caused by diurnally sub-periodic Wuchereria bancrofti transmitted by Aedes vector species. LF prevalence declined very appreciably as a result of chemotherapeutic intervention measures implemented in 1977, but low levels of infection persisted. Along with other Pacific Island countries and in partnership with the Pacific Programme to Eliminate LF (PacELF), Tonga implemented a programme to eliminate LF as a public health problem.MethodsOn the basis of historical data and baseline survey, all the divisions of the country were declared as endemic. Five to six consecutive rounds of effective MDA were implemented in all the divisions during 2001–2006. The impact of MDA was assessed through interim and post-MDA antigen (Ag) detection surveys among adults and transmission assessment surveys among children. The chronic disease burden was assessed by health workers through observation.ResultsThe base-line Ag prevalence was 2.70%. The treatment coverage was > 80% in all MDA rounds. The mid-term surveys showed an Ag prevalence of 2.46%. The pre-stop MDA Ag survey revealed an Ag prevalence of 0.34%. The stop MDA survey and transmission assessment surveys among children showed Ag prevalence at < 0.05%, indicating transmission is negligible. Health workers concluded that filarial lymphedema or hydrocele condition in the communities is absent or very rare.ConclusionTonga had successfully met the criteria for elimination of LF as a public health problem. The accomplishment was acknowledged by the WHO in 2017. Tonga looks forward to work with stakeholders to eliminate transmission of LF and achieve zero incidence of infection.

Evaluation of a Single Dose of Azithromycin for Trachoma in Low-Prevalence Communities

ABSTRACTPurpose: Trachoma, caused by repeated ocular infection with Chlamydia trachomatis, is the leading infectious cause of blindness worldwide and is targeted for elimination as a public health problem. We sought to determine whether a one-time azithromycin mass treatment would reduce trachomatous inflammation–follicular (TF) levels below the elimination threshold of 5% in communities with disease prevalence between 5 and 9.9%.Methods: The study was conducted in 96 sub-village units (balozis) in the Kongwa district of Tanzania which were predicted from prior prevalence surveys to have TF between 5 and 9.9%. Balozis were randomly assigned to the intervention and control arms. The intervention arm received a single mass drug administration of azithromycin. At baseline and 12-month follow-up, ocular exams for trachoma, ocular swabs for detection of chlamydial DNA, and finger prick blood for analysis of anti-chlamydial antibody were taken.Results: Comparison of baseline and 12-month follow-up showed no significant difference in the overall TF1-9 prevalence by balozi between control and treatment arms. In the treatment arm there was a significant reduction of ocular infection 12 months after treatment (p = 0.004) but no change in the control arm. No change in Pgp3-specific antibody responses were observed after treatment in the control or treatment arms. Anti-CT694 responses increased in both study arms (p = 0.009 for control arm and p = 0.04 for treatment arm).Conclusion: These data suggest that a single round of MDA may not be sufficient to decrease TF levels below 5% when TF1-9 is between 5 and 9.9% at baseline.

A cluster randomised controlled trial of two rounds of mass drug administration in Zanzibar, a malaria pre-elimination setting\u2014high coverage and safety, but no significant impact on transmission

BackgroundMass drug administration (MDA) has the potential to interrupt malaria transmission and has been suggested as a tool for malaria elimination in low-endemic settings. This study aimed to determine the effectiveness and safety of two rounds of MDA in Zanzibar, a pre-elimination setting.MethodsA cluster randomised controlled trial was conducted in 16 areas considered as malaria hotspots, with an annual parasite index of > 0.8%. The areas were randomised to eight intervention and eight control clusters. The intervention included two rounds of MDA with dihydroartemisinin-piperaquine and single low-dose primaquine 4 weeks apart in May–June 2016. Primary and secondary outcomes were cumulative confirmed malaria case incidences 6 months post-MDA and parasite prevalences determined by PCR 3 months post-MDA. Additional outcomes included intervention coverage, treatment adherence, occurrence of adverse events, and cumulative incidences 3, 12, and 16 months post-MDA.ResultsIntervention coverage was 91.0% (9959/10944) and 87.7% (9355/10666) in the first and second rounds, respectively; self-reported adherence was 82.0% (881/1136) and 93.7% (985/1196). Adverse events were reported in 11.6% (147/1268) and 3.2% (37/1143) of post-MDA survey respondents after both rounds respectively. No serious adverse event was reported. No difference in cumulative malaria case incidence was observed between the control and intervention arms 6 months post-MDA (4.2 and 3.9 per 1000 population; p = 0.94). Neither was there a difference in PCR-determined parasite prevalences 3 months post-MDA (1.4% and 1.7%; OR = 1.0, p = 0.94), although having received at least the first MDA was associated with reduced odds of malaria infection (aOR = 0.35; p = 0.02). Among confirmed malaria cases at health facilities, 26.0% and 26.3% reported recent travel outside Zanzibar in the intervention and control shehias (aOR ≥ 85; p ≤ 0.001).ConclusionsMDA was implemented with high coverage, adherence, and tolerability. Despite this, no significant impact on transmission was observed. The findings suggest that two rounds of MDA in a single year may not be sufficient for a sustained impact on transmission in a pre-elimination setting, especially when the MDA impact is restricted by imported malaria. Importantly, this study adds to the limited evidence for the use of MDA in low transmission settings in sub-Saharan Africa.Trial registrationClinicalTrials.gov, NCT02721186 (registration date: March 29, 2016)

Mass Drug Administration With Dihydroartemisinin-piperaquine and Malaria Transmission Dynamics in The Gambia: A Prospective Cohort Study.

BackgroundMass drug administration (MDA) may further reduce malaria transmission in low-transmission areas. The impact of MDA on the dynamics of malaria transmission was determined in a prospective cohort study.MethodsAnnual rounds of MDA with dihydroartemisinin-piperaquine (DP) were implemented were implemented in 2014 and 2015 in six village pairs before the malaria transmission season. Blood samples were collected from residents between July and December for microscopy and nested PCR. Incidence and prevalence of infection, clinical disease, and risk of malaria reinfection post-MDA were determined.ResultsCoverage of three DP doses was 68.2% (2014) and 65.6% (2015), compliance was greater than 80%. Incidence of infection was significantly lower in 2014 (incidence rate [IR] = 0.2 per person year [PPY]) than in 2013 (IR = 1.1 PPY; P < .01); monthly infection prevalence declined in the first three months post-MDA. Clinical malaria incidence was lower in 2014 (IR = 0.1 PPY) and 2015 (IR = 0.2 PPY) than in 2013 (IR = 0.4 PPY; P < .01), but remained higher in eastern Gambia. Individuals infected before MDA had a 2-fold higher odds of reinfection post-MDA (adjusted odds ratio = 2.5, 95% confidence interval 1.5–4.3; P < .01).ConclusionsMDA reduced malaria infection and clinical disease during the first months. The reduction was maintained in low-transmission areas, but not in eastern Gambia. Annual MDA could be followed by focal MDA targeting individuals infected during the dry season. Repeated MDA rounds, some during the dry season over larger geographical areas, may result in a more marked and sustained decrease of malaria transmission.

Comprehensive Assessment of a Hotspot with Persistent Bancroftian Filariasis in Coastal Sri Lanka

.The Sri Lankan Anti-Filariasis campaign distributed five rounds of mass drug administration (MDA with diethylcarbamazine plus albendazole) to some 10 million people in eight districts between 2002 and 2006. Sri Lanka was recognized by the WHO for having eliminated lymphatic filariasis (LF) as a public health problem in 2016. However, recent studies by our group documented pockets with persistent LF in coastal Sri Lanka, especially in Galle district. The present study was performed to reexamine an area previously identified as a potential hotspot for persistent LF (Balapitiya Public Health Inspector area, population 17,500). A community survey documented high rates for circulating filarial antigenemia (3%, confidence interval [CI]: 1.8–4.9) and microfilaremia (1%, CI: 0.5–2.5%). Circulating filarial antigenemia rates were 2.8-fold higher in males than females. High prevalence was also observed for anti-filarial antibodies in young children (5.7%, CI: 3.7–8.4%) and for filarial DNA in vector mosquitoes (5.2%, CI: 4.2–6.3%). Spatial data showed that persistent LF was dispersed across the entire study area. Other studies showed that persistent LF was not limited to Balapitiya and not solved by additional rounds of MDA. Molecular xenomonitoring studies conducted in 2016 in 22 of 168 Public Health Midwife areas in the coastal Galle evaluation unit (approximate population 600,000) found that 179 of 660 (27%) pools of Culex collected from all areas were positive for Wuchereria bancrofti DNA by quantitative polymerase chain reaction; the estimated infection rate in mosquitoes was 1.26%, CI: 1.0–1.5%. Interventions other than routine MDA will be required to remove LF hotspots in Balapitiya and in other areas in coastal Sri Lanka.

One round of azithromycin MDA adequate to interrupt transmission in districts with prevalence of trachomatous inflammation-follicular of 5.0-9.9%: Evidence from Malawi.

BackgroundAs highly trachoma-endemic countries approach elimination, some districts will have prevalences of trachomatous inflammation–follicular in 1–9-year-olds (TF1-9) of 5.0–9.9%. The World Health Organization (WHO) previously recommended that in such districts, TF prevalence be assessed in each sub-district (groupings of at least three villages), with three rounds of azithromycin treatment offered to any sub-district in which TF≥10%. Given the large number of endemic districts worldwide and the human and financial resources required to conduct surveys, this recommendation may not be practical. In a group of 8 Malawi districts with baseline TF prevalences of 5.0–9.9%, the Malawi Ministry of Health administered one round of azithromycin mass treatment, to the whole of each district, achieving mean coverage of ~80%. Here, we report impact surveys conducted after that treatment.MethodsWe undertook population-based trachoma surveys in 18 evaluation units of the 8 treated districts, at least 6 months after the MDA. The standardized training package and survey methodologies of Tropical Data, which conform to WHO recommendations, were used.ResultsEach of the 18 evaluation units had a TF1-9 prevalence <5.0%.ConclusionThe study demonstrates that in Malawi districts with TF of 5.0–9.9%, one round of azithromycin MDA with ~80% coverage associates with a reduction in TF prevalence to <5%. Further evidence for this approach should be collected elsewhere.

Community engagement for the rapid elimination of malaria: the case of Kayin State, Myanmar

Background: Currently, malaria elimination efforts are ongoing in several locations across Southeast Asia, including in Kayin State (also known as Karen State), Myanmar . This paper describes the community engagement efforts for a pilot malaria elimination project, the challenges encountered and lessons learnt. Methods: Between May 2013 and June 2015, a study on targeted malaria elimination (TME) that included mass drug administration was conducted in four villages (TPN, TOT, KNH, and HKT) of Kayin State. Community engagement efforts included workshops, meetings and house-to-house visits with community members. Exhibitions related to malaria and fun activities were organized for children. In addition, we provided primary care, small individual incentives and village-level incentives. This paper is based on our analysis of data extracted from meeting minutes, field notes, feedback sessions among staff and with community members as well as our own reflections. Results: Average participation across three rounds of MDA were 84.4%, 57.4%, 88.6% and 59.3% for TPN, TOT, KNH and HKT, respectively. Community engagement was fraught with practical challenges such as seasonal tasks of the villagers. There were challenges in explaining difficult concepts like drug resistance and submicroscopic infection. Another was understanding and navigating the politics of these villages, which are located in politically contested areas. Managing expectations of villagers was difficult as they assumed that the community team must know everything related to health. Conclusions: In the TME project, many different community engagement strategies were employed. We encountered many challenges which included logistical, scientific and political difficulties. An approach that is tailored to the local population is key.

Community engagement for the rapid elimination of malaria: the case of Kayin State, Myanmar.

Currently, malaria elimination efforts are ongoing in several locations across Southeast Asia, including in Kayin State (also known as Karen State), Myanmar . This paper describes the community engagement efforts for a pilot malaria elimination project, the challenges encountered and lessons learnt. Between May 2013 and June 2015, a study on targeted malaria elimination (TME) that included mass drug administration was conducted in four villages (TPN, TOT, KNH, and HKT) of Kayin State. Community engagement efforts included workshops, meetings and house-to-house visits with community members. Exhibitions related to malaria and fun activities were organized for children. In addition, we provided primary care, small individual incentives and village-level incentives. This paper is based on our analysis of data extracted from meeting minutes, field notes, feedback sessions among staff and with community members as well as our own reflections. Average participation across three rounds of MDA were 84.4%, 57.4%, 88.6% and 59.3% for TPN, TOT, KNH and HKT, respectively. Community engagement was fraught with practical challenges such as seasonal tasks of the villagers. There were challenges in explaining difficult concepts like drug resistance and submicroscopic infection. Another was understanding and navigating the politics of these villages, which are located in politically contested areas. Managing expectations of villagers was difficult as they assumed that the community team must know everything related to health. In the TME project, many different community engagement strategies were employed. We encountered many challenges which included logistical, scientific and political difficulties. An approach that is tailored to the local population is key.