Adherence to Mass Drug Administration with Dihydroartemisinin-Piperaquine and Plasmodium falciparum Clearance in Southern Province, Zambia

Reactive Case Detection and Treatment and Reactive Drug Administration for Reducing Malaria Transmission: A Systematic Review and Meta-Analysis

Many countries pursuing malaria elimination implement "reactive" strategies targeting household members and neighbors of index cases to reduce transmission. These strategies include reactive case detection and treatment (RACDT; testing and treating those positive) and reactive drug administration (RDA; providing antimalarials without testing). We conducted systematic reviews of RACDT and RDA to assess their effect on reducing malaria transmission and gathered evidence about key contextual factors important to their implementation. Two reviewers screened titles/abstracts and full-text records using defined criteria (Patient = those in malaria-endemic/receptive areas; Intervention = RACDT or RDA; Comparison = standard of care; Outcome = malaria incidence/prevalence) and abstracted data for meta-analyses. The Grading of Recommendations, Assessment, Development, and Evaluations approach was used to rate certainty of evidence (CoE) for each outcome. Of 1,460 records screened, reviewers identified five RACDT studies (three cluster-randomized controlled trials [cRCTs] and two nonrandomized studies [NRS]) and seven RDA studies (six cRCTs and one NRS); three cRCTs comparing RDA to RACDT were included in both reviews. Compared with RDA, RACDT was associated with nonsignificantly higher parasite prevalence (odds ratio [OR] = 1.85; 95% CI: 0.96-3.57; one study) and malaria incidence (rate ratio [RR] = 1.30; 95% CI: 0.94-1.79; three studies), both very low CoE. Compared with control or RACDT, RDA was associated with non-significantly lower parasite incidence (RR = 0.73; 95% CI: 0.36-1.47; 2 studies, moderate CoE), prevalence (OR = 0.78; 95% CI: 0.52-1.17; 4 studies, low CoE), and malaria incidence (RR = 0.93; 95% CI: 0.82-1.05; six studies, moderate CoE). Evidence for reactive strategies' impact on malaria transmission is limited, especially for RACDT, but suggests RDA might be more effective.

Knowledge about Asymptomatic Malaria and Acceptability of Using Artemisia afra Tea among Health Care Workers (HCWs) in Yaoundé, Cameroon: A Cross-Sectional Survey

Malaria is the most widespread endemic disease in Cameroon, and asymptomatic Plasmodium (gametocyte) carriers (APCs) constitute more than 95% of infectious human reservoirs in malaria endemic settings. This study assesses the knowledge of asymptomatic malaria (ASM) among health care workers (HCWs) in health facilities (HFs) in the Centre Region of Cameroon and the acceptability of using Artemisia afra tea to treat APCs. A cross-sectional descriptive survey was conducted among 100 HCWs, in four randomly selected HFs in the Centre Region, in the period of 1-20 April 2022, using semi-structured self-administered questionnaires. Logistic regression analyses were performed to determine factors associated with knowledge. More than seven in eight (88%) respondents were aware of the existence of ASM, 83% defined ASM correctly, 75% knew how it was diagnosed, 70% prescribe ACTs for APCs, and 51.1% were informed about ASM transmission. The professional category of HCWs was significantly associated with their knowledge of the existence and transmission of ASM, and longevity of service was associated with knowledge of transmission (p < 0.05). Two-thirds (67%) of respondents knew about Artemisia afra tea, 53.7% believed that it was effective in treating ASM, and 79% were willing to prescribe it if authorized. There was a fair level of knowledge of ASM among HCWs in the study settings.

A Systematic Review and Meta-Analysis of Malaria Test Positivity Outcomes and Programme Interventions in Low Transmission Settings in Southern Africa, 2000-2021

Malaria is one of the most significant causes of mortality and morbidity globally, especially in sub-Saharan Africa (SSA) countries. It harmfully disturbs the public’s health and the economic growth of many developing countries. Despite the massive effect of malaria transmission, the overall pooled proportion of malaria positivity rate in Southern Africa is still elusive. Therefore, the objective of this systematic review and meta-analysis is to pool estimates of the incidence of the malaria positivity rate, which is the first of its kind in South African countries. A literature search is performed to identify all published articles reporting the incidence of malaria positivity in Southern Africa. Out of the 3359 articles identified, 17 studies meet the inclusion for systematic review and meta-analysis. In addition, because substantial heterogeneity is expected due to the studies being extracted from the universal population, random-effects meta-analyses are carried out to pool the incidence of the malaria positivity rate from diverse diagnostic methods. The result reveals that between-study variability is high (τ2 = 0.003; heterogeneity I2 = 99.91% with heterogeneity chi-square χ2 = 18,143.95, degree of freedom = 16 and a p-value < 0.0001) with the overall random pooled incidence of 10% (95%CI: 8−13%, I2 = 99.91%) in the malaria positivity rate. According to the diagnostic method called pooled incidence estimate, the rapid diagnostic test (RDT) is the leading diagnostic method (17%, 95%CI: 11−24%, I2 = 99.95%), followed by RDT and qPCR and RDT and loop mediated isothermal amplification (LAMP), respectively, found to be (3%, 95%CI: 2−3%, I2 = 0%) and (2%, 95%CI: 1−3%, I2 = 97.94%).Findings of the present study suggest high malaria positive incidence in the region. This implies that malaria control and elimination programmes towards malaria elimination could be negatively impacted and cause delays in actualising malaria elimination set dates. Further studies consisting of larger samples and continuous evaluation of malaria control programmes are recommended.

Mass drug administration in response to vivax malaria resurgence in Anhui Province of Huanghuai Plain, China

This article summarizes the background, specific conditions, main measures, steps and effects of the implementation of Mass Drug Administration (MDA) to control the local P. vivax malaria epidemic in Anhui Province in central China. Distributing medicines to the designated population quickly controlled the local epidemic of P. vivax. Implementing MDA to control P. vivax ensured the correct selection of medicines, clarification of the targeted population for receipt of medicines, and assurance of a high rate of compliance through government support and health education. These results provide a reference for countries and regions experiencing similar events and planning to implement MDA in malaria control.

Efficacy, Safety and Tolerability of Pyronaridine-artesunate in Asymptomatic Malaria-infected Individuals: a Randomized Controlled Trial

BACKGROUND

Pyronaridine-artesunate (PA) is a registered artemisinin-based combination therapy, potentially useful for mass drug administration campaigns. However, further data are needed to evaluate its efficacy, safety and tolerability as full or incomplete treatment in asymptomatic Plasmodium falciparum-infected individuals.

METHODS

This phase II, multi-center, open label, randomized clinical trial was conducted in The Gambia and Zambia. Participants with microscopically confirmed asymptomatic P. falciparum infection were randomly assigned (1:1:1) to receive a 3-day, 2-day, or 1-day treatment regimen of PA (180:60 mg), dosed according to bodyweight. The primary efficacy outcome was polymerase chain reaction (PCR)-adjusted adequate parasitological response (APR) at day 28 in the per-protocol population.

RESULTS

A total of 303 participants were randomized. Day 28 PCR-adjusted APR was 100% for both the 3-day (98/98) and 2-day regimens (96/96), and 96.8% (89/94) for the 1-day regimen. Efficacy was maintained at 100% until day 63 for the 3-day and 2-day regimens but declined to 94.4% (84/89) with the 1-day regimen. Adverse event frequency was similar between the 3-day (51.5% [52/101]), 2-day (52.5% [52/99]), and 1-day (54.4% [56/103]) regimens; the majority of adverse events were of grade 1 or 2 severity (85% [136/160]). Asymptomatic, transient increases (>3 times the upper limit of normal) in alanine aminotransferase/aspartate aminotransferase were observed for 6/301 (2.0%) participants.

CONCLUSIONS

PA had high efficacy and good tolerability in asymptomatic P. falciparum-infected individuals, with similar efficacy for the full 3-day and incomplete 2-day regimens. Although good adherence to the 3-day regimen should be encouraged, these results support the further investigation of PA for mass drug administration campaigns.

CLINICAL TRIALS REGISTRATION

NCT03814616.

Impact of Four Rounds of Mass Drug Administration with Dihydroartemisinin-Piperaquine Implemented in Southern Province, Zambia

Over the past decade, Zambia has made substantial progress against malaria and has recently set the ambitious goal of eliminating by 2021. In the context of very high vector control and improved access to malaria diagnosis and treatment in Southern Province, we implemented a community-randomized controlled trial to assess the impact of four rounds of community-wide mass drug administration (MDA) and household-level MDA (focal MDA) with dihydroartemisinin-piperaquine (DHAP) implemented between December 2014 and February 2016. The mass treatment campaigns achieved relatively good household coverage (63-79%), were widely accepted by the community (ranging from 87% to 94%), and achieved very high adherence to the DHAP regimen (81-96%). Significant declines in all malaria study end points were observed, irrespective of the exposure group, with the overall parasite prevalence during the peak transmission season declining by 87.2% from 31.3% at baseline to 4.0% in 2016 at the end of the trial. Children in areas of lower transmission (< 10% prevalence at baseline) that received four MDA rounds had a 72% (95% CI = 12-91%) reduction in malaria parasite prevalence as compared with those with the standard of care without any mass treatment. Mass drug administration consistently had the largest short-term effect size across study end points in areas of lower transmission following the first two MDA rounds. In the context of achieving very high vector control coverage and improved access to diagnosis and treatment for malaria, our results suggest that MDA should be considered for implementation in African settings for rapidly reducing malaria outcomes in lower transmission settings.

A Longitudinal Cohort to Monitor Malaria Infection Incidence during Mass Drug Administration in Southern Province, Zambia

Rigorous evidence of effectiveness is needed to determine where and when to apply mass drug administration (MDA) or focal MDA (fMDA) as part of a malaria elimination strategy. The Zambia National Malaria Elimination Centre recently completed a community-randomized controlled trial in Southern Province to evaluate MDA and fMDA for transmission reduction. To assess the role of MDA and fMDA on infection incidence, we enrolled a longitudinal cohort for an 18-month period of data collection including monthly malaria parasite infection detection based on polymerase chain reaction and compared time to first infection and cumulative infection incidence outcomes across study arms using Cox proportional hazards and negative binomial models. A total of 2,026 individuals from 733 households were enrolled and completed sufficient follow-up for inclusion in analysis. Infection incidence declined dramatically across all study arms during the period of study, and MDA was associated with reduced risk of first infection (hazards ratio: 0.36; 95% CI: 0.16–0.80) and cumulative infection incidence during the first rainy season (first 5 months of follow-up) (incidence rate ratio: 0.34; 95% CI: 0.12–0.95). No significant effect was found for fMDA or for either arm over the full study period. Polymerase chain reaction infection status at baseline was strongly associated with follow-up infection. The short-term effects of MDA suggest it may be an impactful accelerator of transmission reduction in areas with high coverage of case management and vector control and should be considered as part of a malaria elimination strategy.

Recent Travel History and Plasmodium falciparum Malaria Infection in a Region of Heterogenous Transmission in Southern Province, Zambia

As Zambia continues to reduce its malaria incidence and target elimination in Southern Province, there is a need to identify factors that can reintroduce parasites and sustain malaria transmission. To examine the relative contributions of types of human mobility on malaria prevalence, this analysis quantifies the proportion of the population having recently traveled during both peak and nonpeak transmission seasons over the course of 2 years and assesses the relationship between short-term travel and malaria infection status. Among all residents targeted by mass drug administration in the Lake Kariba region of Southern Province, 602,620 rapid diagnostic tests and recent travel histories were collected during four campaign rounds occurring between December 2014 and February 2016. Rates of short-term travel in the previous 2 weeks fluctuated seasonally from 0.3% to 1.2%. Travel was significantly associated with prevalent malaria infection both seasonally and overall (adjusted odds ratio [AOR]: 2.55; 95% CI: 2.28-2.85). The strength of association between travel and malaria infection varied by travelers' origin and destination, with those recently traveling to high-prevalence areas from low-prevalence areas experiencing the highest odds of malaria infection (AOR: 7.38). Long-lasting insecticidal net usage while traveling was associated with a relative reduction in infections (AOR: 0.74) compared with travelers not using a net. Although travel was directly associated with only a small fraction of infections, importation of malaria via human movement may play an increasingly important role in this elimination setting as transmission rates continue to decline.

Moving from Malaria Burden Reduction toward Elimination: An Evaluation of Mass Drug Administration in Southern Province, Zambia

From December 2014 to February 2016, a cluster randomized controlled trial was carried out in 60 health facility catchment areas along Lake Kariba in Zambia's Southern Province. The trial sought to evaluate the impact of four rounds of a mass drug administration (MDA) intervention with dihydroartemisinin-piperaquine (DHAP) or focal MDA with DHAP at the household level compared with a control population that received the standard of care. This study was the first randomized controlled trial with DHAP for MDA in sub-Saharan Africa and was conducted through a collaboration between the National Malaria Elimination Programme in the Zambian Ministry of Health, the PATH Malaria Control and Elimination Partnership in Africa, and the Center for Applied Malaria Research and Evaluation at Tulane University. This article serves as an introduction to a collection of articles designed to explore different aspects of the intervention. By describing the recent history of malaria control in Zambia leading up to the trial-from the scale-up of point-of-care diagnosis and treatment, vector control, and indoor residual spraying early in the twenty-first century, to the efforts made to sustain the gains achieved with that approach-it provides a rationale for the implementation of a trial that has informed a new national strategic plan and solidified malaria elimination as Zambia's national goal.

Treatment Coverage Estimation for Mass Drug Administration for Malaria with Dihydroartemisinin-Piperaquine in Southern Province, Zambia

Mass drug administration (MDA) is currently being considered as an intervention in low-transmission areas to complement existing malaria control and elimination efforts. The effectiveness of any MDA strategy is dependent on achieving high epidemiologic coverage and participant adherence rates. A community-randomized controlled trial was conducted from November 2014 to March 2016 to evaluate the impact of four rounds of MDA or focal MDA (fMDA)—where treatment was given to all eligible household members if anyone in the household had a positive malaria rapid diagnostic test—on malaria outcomes in Southern Province, Zambia (population approximately 300,000). This study examined epidemiologic coverage and program reach using capture–recapture and satellite enumeration methods to estimate the degree to which the trial reached targeted individuals. Overall, it was found that the percentage of households visited by campaign teams ranged from 62.9% (95% CI: 60.0–65.8) to a high of 77.4% (95% CI: 73.8–81.0) across four rounds of treatment. When the maximum number of visited households across all campaign rounds was used as the numerator, program reach for at least one visit would have been 86.4% (95% CI: 80.8–92.0) in MDA and 83.5% (95% CI: 78.0–89.1) in fMDA trial arms. As per the protocol, the trial provided dihydroartemisinin–piperaquine treatment to an average of 58.8% and 13.3% of the estimated population based on capture–recapture in MDA and fMDA, respectively, across the four rounds.