Point-of-care circulating cathodic antigen positivity and associated factors in school children one year after mass praziquantel administration in an endemic district in Ghana.

Background: Mass drug administration of praziquantel is expected to reduce Schistosome carriage in treated children in endemic communities. However, the effectiveness of this annual exercise has not been assessed in Ghana. Therefore, this study aimed to detect viable Schistosoma mansoni infection using point-of-care circulating cathodic antigen (POC-CCA) positivity as proxy and associated factors in children previously treated with praziquantel in an endemic municipality in Ghana. Materials and methods: This cross-sectional study was done in the Assin Central municipality in the Central Region of Ghana. School children, less than 16 years of age, treated with 40 mg/kg of praziquantel (treatment period: February-March 2019), provided early morning urine (∼40 mL) and stool (∼4 g) samples. Immediately, POC-CCA (ICT International, South Africa) was done, while S. mansoni ova were detected in formalin fixed samples using microscopy later. Additionally, participant's socio-demographic information and factors associated with S, mansoni infection transmission were collected from each child. Results: A total of 520 children participated in the study (males-51.9%, majority age range [9-11 years, 34.4%]). Overall, 244 (46.9%) were positive for urinary CCA with no S. mansoni detected by microscopy. POC-CCA positivity was higher in females (48.4%), children with 2-3 siblings (49.3%), children aged 6-8-year range (55.4%) and residents of Brofoyedur (52%). However, age (x2 = 16.1, p = 0.0003) and town of residence (x2 = 11.7, p = 0.019) associated with CCA positivity. Further, location of water body (x2 = 16.4, p = 0.008), frequency of water contact (x2 = 12.3, p = 0.015) and handling of the Biomphalaria intermediate host (x2 = 5.1, p = 0.024) associated with POC-CCA outcome. Conclusion: About 47% of the school children were positive for CCA, one year after mass praziquantel administration in the Assin Central municipality. Varied factors associated with the post-praziquantel administration POC-CCA positivity. This study should be replicated in other endemic areas to identify groups at risk of parasite persistence or reinfection to inform modification of control and preventive measures.

Molecular speciation of Plasmodium and multiplicity of P. falciparum infection in the Central region of Ghana.

Malaria is endemic in the Central region of Ghana, however, the ecological and the seasonal variations of Plasmodium population structure and the intensity of malaria transmission in multiple sites in the region have not been explored. In this cross-sectional study, five districts in the region were involved. The districts were Agona Swedru, Assin Central and Gomoa East (representing the forest zone) and Abura-Asebu-Kwamankese and Cape Coast representing the coastal zone. Systematically, blood samples were collected from patients with malaria. The malaria status was screened with a rapid diagnostic test (RDT) kit (CareStart manufactured by Access Bio in Somerset, USA) and the positive ones confirmed microscopically. Approximately, 200 µL of blood was used to prepare four dried blood spots of 50µL from each microscopy positive sample. The Plasmodium genome was sequenced at the Malaria Genome Laboratory (MGL) of Wellcome Sanger Institute (WSI), Hinxton, UK. The single nucleotide polymorphisms (SNPs) in the parasite mitochondria (PfMIT:270) core genome aided the species identification of Plasmodium. Subsequently, the complexity of infection (COI) was determined using the complexity of infection likelihood (COIL) computational analysis. In all, 566 microscopy positive samples were sequenced. Of this number, Plasmodium genome was detected in 522 (92.2%). However, whole genome sequencing was successful in 409/522 (72.3%) samples. In total, 516/522 (98.8%) of the samples contained P. falciparum mono-infection while the rest (1.2%) were either P. falciparum/P. ovale (Pf/Po) (n = 4, 0.8%) or P. falciparum/P. malariae/P. vivax (Pf/Pm/Pv) mixed-infection (n = 2, 0.4%). All the four Pf/Po infections were identified in samples from the Assin Central municipality whilst the two Pf/Pm/Pv triple infections were identified in Abura-Asebu-Kwamankese district and Cape Coast metropolis. Analysis of the 409 successfully sequenced genome yielded between 1-6 P. falciparum clones per individual infection. The overall mean COI was 1.78±0.92 (95% CI: 1.55-2.00). Among the study districts, the differences in the mean COI between ecological zones (p = 0.0681) and seasons (p = 0.8034) were not significant. However, regression analysis indicated that the transmission of malaria was more than twice among study participants aged 15-19 years (OR = 2.16, p = 0.017) and almost twice among participants aged over 60 years (OR = 1.91, p = 0.021) compared to participants between 20-59 years. Between genders, mean COI was similar except in Gomoa East where females recorded higher values. In conclusion, the study reported, for the first time, P. vivax in Ghana. Additionally, intense malaria transmission was found to be higher in the 15-19 and > 60 years, compared to other age groups. Therefore, active surveillance for P. vivax in Ghana and enhanced malaria control measures in the 15-19 year group years and those over 60 years are recommended.

Immunochromatographic and microscopic detection of Plasmodium falciparum in recipients of P. falciparum-infected donor blood.

Blood transfusion practice is an essential medical intervention; however, it poses problems of transmissibility of infectious diseases including malaria. This study was designed to determine the potential of transfusion-transmitted malaria (TTM) by detecting malaria antigens and parasites in recipients of infected donor blood. After successful blood transfusion, remnants of transfused blood were screened for Plasmodium falciparum HRP2 antigen and parasitemia using CareStart malaria RDT and 10% Giemsa stain microscopy respectively according to established protocols. Recipients of microscopy detectable P. falciparum in infected blood who tested negative for malaria by both microscopy and mRDT prior to receiving infected donor blood were followed up weekly for 35 days. Donor P. falciparum antigenemia and parasitemia were 12.1% and 8.4%, respectively, while the prevalence of blood recipient parasitemia was 3.2%. Blood stored for 2-5 days recorded mean parasitemia higher than those stored for a day and after 5 days. Additionally, parasitemia was observed in all follow-up days with marginally high frequencies in days 7, 14, and 35. There was no association between the attributes (storage days, blood group, and parasite count range) of the infected donor blood units and the characteristics of blood recipients with post-transfusion parasitemia. This study provides baseline data on TTM in Ghana. However, further studies should establish the genetic relatedness of the implicated parasites since new infections and/or recrudescence of previous infections could account for this observation.