Effect of anti-malarial interventions on trends of malaria cases, hospital admissions and deaths, 2005-2015, Ghana

Abstract

Background: Since 2005, the Government of Ghana and its partners, in concerted efforts to control malaria, scaled up the use of artemisinin-based combination therapy (ACT) and insecticide-treated nets (ITNs). Beginning in 2011, a mass campaign of long-lasting insecticidal nets (LLINs) was implemented, targeting all the population. The impact of these interventions on malaria cases, admissions and deaths was assessed using data from district hospitals.

Methods: Records of malaria cases and deaths and availability of ACT in 88 hospitals, as well as at district level, ITN distribution, and indoor residual spraying were reviewed. Annual proportion of the population potentially protected by ITNs was estimated with the assumption that each LLIN covered 1.8 persons for 3 years. Changes in trends of cases and deaths in 2015 were estimated by segmented log-linear regression, comparing trends in post-scale-up (2011-2015) with that of pre-scale-up (2005-2010) period. Trends of mortality in children under 5 years old from population-based household surveys were also compared with the trends observed in hospitals for the same time period.

Results: Among all ages, the number of outpatient malaria cases (confirmed and presumed) declined by 57% (95% confidence interval [CI], 47-66%) by first half of 2015 (during the post-scale-up) compared to the pre-scale-up (2005-2010) period. The number of microscopically confirmed cases decreased by 53% (28-69%) while microscopic testing was stable. Test positivity rate (TPR) decreased by 41% (19-57%). The change in malaria admissions was insignificant while malaria deaths fell significantly by 65% (52-75%). In children under 5 years old, total malaria outpatient cases, admissions and deaths decreased by 50% (32-63%), 46% (19-75%) and 70% (49-82%), respectively. The proportion of outpatient malaria cases, admissions and deaths of all-cause conditions in both all ages and children under five also fell significantly by >30%. Similar decreases in the main malaria indicators were observed in the three epidemiological strata (coastal, forest, savannah). All-cause admissions increased significantly in patients covered by the National Health Insurance Scheme (NHIS) compared to the non-insured. The non-malaria cases and non-malaria deaths increased or remained unchanged during the same period. All-cause mortality for children under 5 years old in household surveys, similar to those observed in the hospitals, declined by 43% between 2008 and 2014.

Conclusions: The data provide compelling evidence of impact following LLIN mass campaigns targeting all ages since 2011, while maintaining other anti-malarial interventions. Malaria cases and deaths decreased by over 50 and 65%, respectively. The declines were stronger in children under five. Test positivity rate in all ages decreased by >40%. The decrease in malaria deaths was against a backdrop of increased admissions owing to free access to hospitalization through the NHIS. The study demonstrated that retrospective health facility-based data minimize reporting biases to assess effect of interventions. Malaria control in Ghana is dependent on sustained coverage of effective interventions and strengthened surveillance is vital to monitor progress of these investments.

Keywords: Ghana; Impact; Indoor residual spraying; LLIN mass campaign; Malaria.

Fig. 1

Timing of implementation of anti-malarial interventions in Ghana, 2005–2015 ACT in public sector scaled-up since 2005; ITNs targeting children under five and pregnant women until 2010 and universal coverage of LLINs targeting all population since 2011; IRS in limited number of northern districts since 2007; health insurance scheme since 2005

Fig. 2

Trends in TPR, percentage of population protected with LLINs, IRS and percentage of health facilities with stock of ACT available by year, 2005–2015, Ghana

Fig. 3

Biannual trends of cases and deaths in 88 hospitals, 2005–2012, Ghana. a Trends of confirmed malaria cases versus non-malaria outpatient cases; b TPR versus cases tested with microscopy; c malaria admissions versus non-malaria admissions; d malaria deaths versus non-malaria deaths; e proportion of outpatient malaria cases (PropOPD), admissions (PropIPD), and deaths of all-cause conditions (PropDth); f severe anaemia admissions and anaemia deaths

Fig. 4

All-cause deaths and malaria deaths in children under five at hospital and population level during 2005–2015. a Under five all-cause and malaria deaths in hospitals; b Under five all-cause deaths at population level

Fig. 5

Trends of all-cause admissions among insured and non-insured patients (Ghana MoH). a All-cause admissions in absolute values; b all-cause admissions compared (indexed) to baseline 2008

Fig. 6

Rainfall, minimum temperature (°C), maximum temperature, trends of malaria deaths and TPR. a Rainfall (mm), minimum and maximum temperature (°C); b rainfall, malaria deaths and TPR