Characteristics of asymptomatic Plasmodium spp. parasitaemia in Kwahu-Mpraeso, a malaria endemic mountainous district in Ghana, West Africa

Abstract

BackgroundMalaria control efforts in Ghana have reduced the countrywide average malaria prevalence from 71 % in 2000 to about 51 % in 2012; however, its main focus is on symptomatic malaria. If further progress is to be made, parasite reservoirs in asymptomatic carriers need to be moved into focus. This study profiles asymptomatic Plasmodium spp. parasitaemia amongst residents of mountainous Kwahu-Mpraeso in the Eastern region of Ghana.MethodsA cross-sectional study of 360 residents was carried out from October to December 2013. This included recording demographics, malaria testing of asymptomatic residents, and gathering of their malaria history. Assessment of malaria transmission was done with molecular identification of vectors, determination of sporozoite rate, insecticide resistance status and biting pattern. Univariate and multivariate analysis were used to establish risk determinants.ResultsIn Mpraeso, in the Kwahu highland of Eastern Region, children were at higher risk of asymptomatic parasitaemia, thereby contributing to the parasite reservoir and hence sustained malaria transmission. As well, findings suggested Hb AC genotype influenced susceptibility to asymptomatic malaria with 8.03-fold increase in odds (univariate) and 11.92-fold higher odds (multivariate) than the normal Hb AA. The mosquito vector predominant in the area was Anopheles gambiae sensu stricto of the homozygous pyrethroid resistant form (RR); with biting mainly occurring indoors.ConclusionFor an effective malaria control in this area, interventions should be formulated and implemented to target asymptomatic parasite reservoirs; especially in children and people with Hb AC. The dominant vector species An. gambiae s.s. and its feeding patterns of biting indoors should also be considered.

Seasonal Variation in the Epidemiology of Asymptomatic Plasmodium falciparum Infections across Two Catchment Areas in Bongo District, Ghana

“…The prevalence of asymptomatic P. falciparum infections by microscopy differed between the age groups surveyed, gradually increasing during childhood and then declining from late adolescences into adulthood. This age-dependent trend in microscopic prevalence was in agreement with previous studies [42][43][44] and was observed at the end of the wet and dry seasons across both catchment areas in BD. These results indicate the importance of understanding the burden of disease and consequences of asymptomatic malaria in the adolescent population, which have traditionally been neglected and rarely targeted for malaria control.…”

“…14,33,53 Recent findings from an area with intense seasonal malaria in Burkina Faso suggests that submicroscopic parasite carriers are an important source of onward transmission, particularly at the end of the dry season, and are responsible for about half of the infectious P. falciparum reservoir. 4 Although our results are similar to previous studies and demonstrate that asymptomatic infections made up a substantial portion of the P. falciparum reservoir across all ages, 42,44,48,54 their ability to produce mature gametocytes and transmit remains vague based on the microscopy results. Further work to evaluate the potential contribution of these asymptomatic infections for onward transmission needs to be assessed and monitored using more sensitive methods if we are to implement appropriate elimination strategies in BD.…”

Assessing Climate Driven Malaria Variability in Ghana Using a Regional Scale Dynamical Model

“…This result clearly shows the model's ability to resolve the important temperature-dependent development rate for both the vector and the parasite. In addition, the model simulated mean lower EIR value of 0.063 ib/p/n (range between 0.012 and 0.137) for Abetifi is close to the value of 0.041 ib/p/n reported by Owusu et al [51] in Kwahu-Mpraeso about 10 km from Abetifi. This clearly shows that malaria is still prevalent in the high altitude areas in Ghana although transmission levels are low.…”

Prevalence of Asymptomatic Malaria among Children in the Tamale Metropolis: How Does the PfHRP2 CareStart™ RDT Perform against Microscopy?

“…is drastic reduction could probably be attributed to the numerous policies and control interventions put in place by the government and several other nongovernmental organizations. e prevalence showed by the RDT was, however, comparable to the 11.94% reported by Owusu et al [24] in the southern part of Ghana even though the study was conducted during the rainy season during which malaria transmission is high. While the RDT presented a greater prevalence of malaria among asymptomatic males, it was, however, not significant statistically (p � 0.126).…”