Malaria rapid diagnostic test (HRP2/pLDH) positivity, incidence, care accessibility and impact of community WASH Action programme in DR Congo: mixed method study involving 625 households

Abstract

Background: Malaria is one of the most prevalent and deadliest illnesses in sub-Saharan Africa. Despite recent gains made towards its control, many African countries still have endemic malaria transmission. This study aimed to assess malaria burden at household level in Kongo central province, Democratic Republic of Congo (DRC), and the impact of community participatory Water, Sanitation and Hygiene (WASH) Action programme.

Methods: Mixed method research was conducted in two semi-rural towns, Mbanza-Ngungu (a WASH action site) and Kasangulu (a WASH control site) in DRC between 1 January 2017 through March 2018, involving 625 households (3,712 household members). Baseline and post-intervention malaria surveys were conducted with the use of World Bank/WHO Malaria Indicator Questionnaire. An action research consisting of a six-month study was carried out which comprised two interventions: a community participatory WASH action programme aiming at eliminating mosquito breeding areas in the residential environment and a community anti-malaria education campaign. The latter was implemented at both study sites. In addition, baseline and post-intervention malaria rapid diagnostic test (RDT) was performed among the respondents. Furthermore, a six-month hospital-based epidemiological study was conducted at selected referral hospitals at each site from 1 January through June 2017 to determine malaria trend.

Results: Long-lasting insecticide-treated net (LLIN) was the most commonly used preventive measure (55%); 24% of households did not use any measures. Baseline malaria survey showed that 96% of respondents (heads of households) reported at least one episode occurring in the previous six months; of them only 66.5% received malaria care at a health setting. In the Action Research, mean incident household malaria cases decreased significantly at WASH action site (2.3 ± 2.2 cases vs. 1.2 ± 0.7 cases, respectively; p < 0.05), whereas it remained unchanged at the Control site. Similar findings were observed with RDT results. Data collected from referral hospitals showed high malaria incidence rate, 67.4%. Low household income (ORa = 2.37; 95%CI: 1.05-3.12; p < 0.05), proximity to high risk area for malaria (ORa = 5.13; 95%CI: 2-29-8.07; p < 0.001), poor WASH (ORa = 4.10; 95%CI: 2.11-7.08; p < 0.001) were predictors of household malaria.

Conclusion: This research showed high prevalence of positive malaria RDT among the responders and high household malaria incidence, which were reduced by a 6-month WASH intervention. DRC government should scale up malaria control strategy by integrating efficient indoor and outdoor preventive measures and improve malaria care accessibility.

Keywords: Democratic republic of congo; Household malaria; Incidence; Malaria care; Rapid diagnostic test.

Fig. 1

Maps of DR Congo (a) showing the study area in Kongo central province and main study flow chart (b) comprising both study designs of the main study ( Source of original maps: Celine Lahaye, ADES-DyMSET (2006) and CAID – DR Congo (Cellule d’ Analyse des Indicateurs de Developpement), 2017). RDT, rapid diagnostic test for malaria; WASH, water, sanitation and hygiene

Fig. 2

Malaria preventive measures used by household members. IRS, indoor residual spraying; LLIN, long-lasting insecticide treated net. The figure shows that LLIN was the most used anti-malaria measure (55%) in households followed by mosquito repellent (15%), whereas 24% of households did not use any preventive measure (p < 0.05)

Fig. 3

Prevalence of positive RDT for malaria among the respondents (household heads). NS, not significant; RDT + , rapid diagnostic test for malaria; WASH, water, sanitation and hygiene. The figure shows a significant decrease of prevalence rate of positive RDT at WASH action site (38% vs. 20%; p < 0.05) as compared to baseline RDT result

Fig. 4

Survey-based self-reported incident household malaria before (baseline) and after interventions. SD, standard deviation; p, p-value. The figure shows a significant decrease in incident malaria cases (mean values) among household members at WASH action site following interventions (p < 0.05)

Fig. 5

Spatial distribution of household incident malaria by risk category of residential area (a) and proximity of risk geographical high malaria risk area (b) (GIS-based data). The figure shows that higher malaria incidence was found among households living in proximity to high malaria risk areas such as grassy areas/stagnant water (60.9%) and residences near river (15.7%)

Fig. 6

Hospital-based malaria incidence trend at referral hospitals located in study sites, Kongo Central province, DR Congo. Figure 6 shows high malaria incidence rates in the two referral health settings that participated in this study (a), in pediatric departments (b), study sites (c). When considering hospital-based monthly incidence rate in first semester of 2017 (d), malaria was more frequent in February, April and May which correspond to months with high pluviometry in western area of DR Congo