We set out to analyze the five-year data of the Sunyani municipality from 2015 to 2019 to identify the distribution of malaria cases by person, place and time and to determine the timeliness and completeness of malaria report submission in the municipality.
In analyzing the distribution of malaria cases in the municipality by person, approximately 55.7% of the persons diagnosed with malaria were females. This could be explained by the higher proportion of females than males in the municipality’s general population [15]. This is consistent with the findings of a study conducted in Manicaland province Zimbabwe, where 52.5% of cases confirmed were females [16]. The similarity in result could likely be explained by the Manicaland province and Sunyani municipality’s similar population structure. Each of them has over 52% of its population being females [15], [17]. Despite the higher malaria cases among females in the general population, we found that the prevalence of malaria was higher among male children than female children under five years. This finding was consistent with similar studies in Ghana and Kenyan [18], [19]. The authors attributed the disparity to female children being less biologically vulnerable to infectious diseases than their male counterparts.
About one-third of confirmed cases of malaria were in children under five years. This is similar to what Bajoga et al., (2019) reported in Kaduna, Nigeria. Malaria cases were fewer among children less than one year. This may be partly explained by the increased push to combat malaria through a combination of interventions such as enhanced ITN coverage, improved antenatal care and IPTP-SP uptake [21]. Among the children less than a year old, neonates had the lowest proportion of malaria infections. This may be because, during pregnancy, neonates obtained antibodies from their mothers [18]. Furthermore, a study conducted by Stephens et al., (2017) found that pregnant women exposed to complete IPTp-SP had better protection with reduced placental parasitemia while serving as a buffer for their neonates.
The Sunyani municipality recorded a high malaria case fatality rate of 5.1% with about 3.4% fatality rate among children under five years of age. The high fatality rate among the under five years could be attributed to the delay in getting these children to a health facility for medical care before the onset of complications. However, this finding is inconsistent with the malaria case fatality rate reported by the National Malaria Control Program for the year 2017. The difference in the fatality rate could be attributed to the difference in the population size under surveillance.
The Abesim sub-district registered the highest malaria burden in the municipality from 2015–2019. This could be explained by the Ghana Water Company water treatment plant’s presence in the area that could serve as a breeding ground for mosquitoes and hence the high transmission rate. This finding is similar to a work conducted in Central Ethiopia, where villages with irrigation dams were found to have 3.6 times increased odds of malaria transmission compared to villages without irrigation plants [23]. We ruled out other factors such as high reporting rate by facilities in the area or population proportion compared to the other sub-districts as possible factors accounting for the high transmission in the area.
In the municipality, there was a seasonal variation to the transmissions of malaria over the five years. Cases of malaria were more pronounced in May, June and October of every year for the period. This could be explained by the municipality’s rainfall pattern, where the major rainfalls occur from March to September and the minor one between October and December each year. This result is consistent with the findings of a study conducted in Limpopo to assess the climatic variables and malaria transmission; they reported that monthly rainfall was the main predictor of malaria transmission [24]. However, this is inconsistent with the findings of a similar study conducted in northeastern rural Benin where the authors’ associated high incidence of malaria with dry or drought seasons of the year [25]. The disparity in this finding could be explained by the difference in the climate of the areas [12], [25]. The municipality experienced an excess case count above the threshold levels in May and October 2016 and October of 2018. This could be suggestive of an outbreak of malaria. This is consistent with the findings of Lechthaler et al., (2019) & Ogwang et al., (2018) where they detected malaria epidemics from trend analysis of malaria data in Kitgum district Uganda and DR Congo. However, in the case of Sunyani municipality, certain factors needed to be ruled out to confirm the status of the increase, whether it was a true or false increase. These factors include; batch reporting of cases by facilities, changes in reporting practices of surveillance officers, errors in the reporting of cases and improvements in diagnostic methods for malaria. Also, malaria being an episodic disease could have resulted in over-reporting, which was suggestive of the outbreak.
For the five years under review, the timeliness and completeness of malaria report submission by the sub-districts in the municipality was low with none of the sub-districts meeting the WHO target of 80% for completeness and timeliness of IDSR monthly reports submission. The poor timeliness of report submission is consistent with the findings of a study conducted in Malawi [14]. In contrast to this finding, studies conducted in northern Ghana and Uganda reported reasonable rates on timeliness and completeness of IDSR monthly report submission [28], [29].
There were a few limitations to this study. Firstly, malaria is an episodic disease, and the number of cases reported could have been influenced by over-reporting in the municipality. Secondly, some private health facilities in the municipality were not reporting malaria morbidity and mortality data; this could have affected the municipality’s actual burden. However, we kept in many efforts to retrieve data from private health facilities and compare hardcopies IDSR forms and hospital registers to the records in the DHIMS 2 to make the findings of this analysis significant and informing.