Epidemiology of malaria among pregnant women during their first antenatal clinic visit in the middle belt of Ghana: a cross sectional study.

BACKGROUND: Malaria during pregnancy may result in unfavourable outcomes in both mothers and their foetuses. This study sought to document the current burden and factors associated with malaria and anaemia among pregnant women attending their first antenatal clinic visit in an area of Ghana with perennial malaria transmission. METHODS: A total of 1655 pregnant women aged 18 years and above with a gestational age of 13-22 weeks, who attended an antenatal care (ANC) clinic for the first time, were consented and enrolled into the study. A structured questionnaire was used to collect socio-demographic and obstetric data and information on use of malaria preventive measures. Venous blood (2 mL) was collected before sulfadoxine-pyrimethamine administration. Malaria parasitaemia and haemoglobin concentration were determined using microscopy and an automated haematology analyser, respectively. Data analysis was carried out using Stata 14. RESULTS: Mean age (SD) and gestational age (SD) of women at enrolment were 27.4 (6.2) years and 16.7 (4.3) weeks, respectively. Overall malaria parasite prevalence was 20.4% (95% CI 18.5-22.4%). Geometric mean parasite density was 442 parasites/µL (95% CI 380-515). Among women with parasitaemia, the proportion of very low (1-199 parasites/µL), low (200-999 parasites/µL), medium (1000-9999 parasites/µL) and high (≥ 10,000 parasites/µL) parasite density were 31.1, 47.0, 18.9, and 3.0%, respectively. Age ≥ 25 years (OR 0.57, 95% CI 0.41-0.79), multigravid (OR 0.50, 95% CI 0.33-0.74), educated to high school level or above (OR 0.53, 95% CI 0.33-0.83) and in household with higher socio-economic status (OR 0.34, 95% CI 0.21-0.54) were associated with a lower risk of malaria parasitaemia. The prevalence of anaemia (< 11.0 g/dL) was 56.0%, and the mean haemoglobin concentration in women with or without parasitaemia was 9.9 g/dL or 10.9 g/dL, respectively. CONCLUSION: One out of five pregnant women attending their first ANC clinic visit in an area of perennial malaria transmission in the middle belt of Ghana had Plasmodium falciparum infection. Majority of the infections were below 1000 parasites/µL and with associated anaemia. There is a need to strengthen existing malaria prevention strategies to prevent unfavourable maternal and fetal birth outcomes in this population.

Non-malaria fevers in a high malaria endemic area of Ghana.

BACKGROUND: The importance of fevers not due to malaria [non-malaria fevers, NMFs] in children in sub-Saharan Africa is increasingly being recognised. We have investigated the influence of exposure-related factors and placental malaria on the risk of non-malaria fevers among children in Kintampo, an area of Ghana with high malaria transmission. METHODS: Between 2008 and 2011, a cohort of 1855 newborns was enrolled and followed for at least 12 months. Episodes of illness were detected by passive case detection. The primary analysis covered the period from birth up to 12 months of age, with an exploratory analysis of a sub-group of children followed for up to 24 months. RESULTS: The incidence of all episodes of NMF in the first year of life (first and subsequent) was 1.60 per child-year (95 % CI 1.54, 1.66). The incidence of NMF was higher among infants with low birth weight [adjusted hazard ratio (aHR) 1.22 (95 % CI 1.04-1.42) p = 0.012], infants from households of poor socio-economic status [aHR 1.22 (95 % CI 1.02-1.46) p = 0.027] and infants living furthest from a health facility [aHR 1.20 (95 % CI 1.01-1.43) p = 0.037]. The incidence of all episodes of NMF was similar among infants born to mothers with or without placental malaria [aHR 0.97 (0.87, 1.08; p = 0.584)]. CONCLUSION: The incidence of NMF in infancy is high in the study area. The incidence of NMF is associated with low birth weight and poor socioeconomic status but not with placental malaria.

Evaluation of the diagnostic accuracy of CareStart G6PD deficiency Rapid Diagnostic Test (RDT) in a malaria endemic area in Ghana, Africa.

BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most widespread enzyme defect that can result in red cell breakdown under oxidative stress when exposed to certain medicines including antimalarials. We evaluated the diagnostic accuracy of CareStart G6PD deficiency Rapid Diagnostic Test (RDT) as a point-of-care tool for screening G6PD deficiency. METHODS: A cross-sectional study was conducted among 206 randomly selected and consented participants from a group with known G6PD deficiency status between February 2013 and June 2013. A maximum of 1.6ml of capillary blood samples were used for G6PD deficiency screening using CareStart G6PD RDT and Trinity qualitative with Trinity quantitative methods as the "gold standard". Samples were also screened for the presence of malaria parasites. Data entry and analysis were done using Microsoft Access 2010 and Stata Software version 12. Kintampo Health Research Centre Institutional Ethics Committee granted ethical approval. RESULTS: The sensitivity (SE) and specificity (SP) of CareStart G6PD deficiency RDT was 100% and 72.1% compared to Trinity quantitative method respectively and was 98.9% and 96.2% compared to Trinity qualitative method. Malaria infection status had no significant (P=0.199) change on the performance of the G6PD RDT test kit compared to the "gold standard". CONCLUSIONS: The outcome of this study suggests that the diagnostic performance of the CareStart G6PD deficiency RDT kit was high and it is acceptable at determining the G6PD deficiency status in a high malaria endemic area in Ghana. The RDT kit presents as an attractive tool for point-of-care G6PD deficiency for rapid testing in areas with high temperatures and less expertise. The CareStart G6PD deficiency RDT kit could be used to screen malaria patients before administration of the fixed dose primaquine with artemisinin-based combination therapy.

Biochemical and hematologic parameters for children in the middle belt of Ghana.

Reference values derived from developed countries are used in many countries in Africa for interpretation of laboratory results obtained during routine healthcare and clinical trials. Use of locally derived reference values has been recommended. The purpose of the study was to establish age- and sex-specific reference values for children in the middle belt of Ghana. Reference values were determined for 21 biochemical and 18 hematologic parameters by using Clinical and Laboratory Standards Institute C28-A3 guidelines in a sample of 1,442 healthy children. Hemoglobin, hematocrit, mean cell volume, erythrocytes, urea, and creatinine were lower when compared with values from northern countries but alanine aminotransferase, aspartate aminotransferase, and total bilirubin were higher. A panel of locally relevant age- and sex-specific reference values was established for commonly used biochemical and hematologic tests in children in the middle part of Ghana. This will help in interpretation of laboratory results for clinical management of patients, screening, and safety monitoring during clinical trials.

Haematological and biochemical reference values for healthy adults in the middle belt of Ghana.

BACKGROUND: Reference values are very important in clinical management of patients, screening participants for enrollment into clinical trials and for monitoring the onset of adverse events during these trials. The aim of this was to establish gender-specific haematological and biochemical reference values for healthy adults in the central part of Ghana. METHODS: A total of 691 adults between 18 and 59 years resident in the Kintampo North Municipality and South District in the central part of Ghana were randomly selected using the Kintampo Health and Demographic Surveillance System and enrolled in this cross-sectional survey. Out of these, 625 adults made up of 316 males and 309 females were assessed by a clinician to be healthy. Median values and nonparametric 95% reference values for 16 haematology and 22 biochemistry parameters were determined for this population based on the Clinical Laboratory and Standards Institute guidelines. Values established in this study were compared with the Caucasian values being used currently by our laboratory as reference values and also with data from other African and western countries. RESULTS: REFERENCE VALUES ESTABLISHED INCLUDE: haemoglobin 113-164 g/L for males and 88-144 g/L for females; total white blood cell count 3.4-9.2 × 10(9)/L; platelet count 88-352 × 10(9)/L for males and 89-403 × 10(9)/L for females; alanine aminotransferase 8-54 U/L for males and 6-51 U/L for females; creatinine 56-119 µmol/L for males and 53-106 µmol/L for females. Using the haematological reference values based on the package inserts would have screened out up to 53% of potential trial participants and up to 25% of the population using the biochemical parameters. CONCLUSION: We have established a panel of locally relevant reference parameters for commonly used haematological and biochemical tests. This is important as it will help in the interpretation of laboratory results both for clinical management of patients and safety monitoring during a trial.

Safety and efficacy of the RTS,S/AS01E candidate malaria vaccine given with expanded-programme-on-immunisation vaccines: 19 month follow-up of a randomised, open-label, phase 2 trial.

BACKGROUND: The RTS,S/AS01(E) candidate malaria vaccine is being developed for immunisation of infants in Africa through the expanded programme on immunisation (EPI). 8 month follow-up data have been reported for safety and immunogenicity of RTS,S/AS01(E) when integrated into the EPI. We report extended follow-up to 19 months, including efficacy results. METHODS: We did a randomised, open-label, phase 2 trial of safety and efficacy of the RTS,S/AS01(E) candidate malaria vaccine given with EPI vaccines between April 30, 2007, and Oct 7, 2009, in Ghana, Tanzania, and Gabon. Eligible children were 6-10 weeks of age at first vaccination, without serious acute or chronic illness. All children received the EPI diphtheria, tetanus, pertussis (inactivated whole-cell), and hepatitis-B vaccines, Haemophilus influenzae type b vaccine, and oral polio vaccine at study months 0, 1, and 2, and measles vaccine and yellow fever vaccines at study month 7. Participants were randomly assigned (1:1:1) to receive three doses of RTS,S/AS01(E) at 6, 10, and 14 weeks (0, 1, 2 month schedule) or at 6 weeks, 10 weeks, and 9 months (0, 2, 7 month schedule) or placebo. Randomisation was according to a predefined block list with a computer-generated randomisation code. Detection of serious adverse events and malaria was by passive case detection. Antibodies against Plasmodium falciparum circumsporozoite protein and HBsAg were monitored for 19 months. This study is registered with ClinicalTrials.gov, number NCT00436007. FINDINGS: 511 children were enrolled. Serious adverse events occurred in 57 participants in the RTS,S/AS01(E) 0, 1, 2 month group (34%, 95% CI 27-41), 47 in the 0, 1, 7 month group (28%, 21-35), and 49 (29%, 22-36) in the control group; none were judged to be related to study vaccination. At month 19, anticircumsporozoite immune responses were significantly higher in the RTS,S/AS01(E) groups than in the control group. Vaccine efficacy for the 0, 1, 2 month schedule (2 weeks after dose three to month 19, site-adjusted according-to-protocol analysis) was 53% (95% CI 26-70; p=0·0012) against first malaria episodes and 59% (36-74; p=0·0001) against all malaria episodes. For the entire study period, (total vaccinated cohort) vaccine efficacy against all malaria episodes was higher with the 0, 1, 2 month schedule (57%, 95% CI 33-73; p=0·0002) than with the 0, 1, 7 month schedule (32% CI 16-45; p=0·0003). 1 year after dose three, vaccine efficacy against first malaria episodes was similar for both schedules (0, 1, 2 month group, 61·6% [95% CI 35·6-77·1], p<0·001; 0, 1, 7 month group, 63·8% [40·4-78·0], p<0·001, according-to-protocol cohort). INTERPRETATION: Vaccine efficacy was consistent with the target put forward by the WHO-sponsored malaria vaccine technology roadmap for a first-generation malaria vaccine. The 0, 1, 2 month vaccine schedule has been selected for phase 3 candidate vaccine assessment. FUNDING: Program for Appropriate Technology in Health Malaria Vaccine Initiative; GlaxoSmithKline Biologicals.

T cell responses to the RTS,S/AS01(E) and RTS,S/AS02(D) malaria candidate vaccines administered according to different schedules to Ghanaian children.

BACKGROUND: The Plasmodium falciparum pre-erythrocytic stage candidate vaccine RTS,S is being developed for protection of young children against malaria in sub-Saharan Africa. RTS,S formulated with the liposome based adjuvant AS01(E) or the oil-in-water based adjuvant AS02(D) induces P. falciparum circumsporozoite (CSP) antigen-specific antibody and T cell responses which have been associated with protection in the experimental malaria challenge model in adults. METHODS: This study was designed to evaluate the safety and immunogenicity induced over a 19 month period by three vaccination schedules (0,1-, 0,1,2- and 0,1,7-month) of RTS,S/AS01(E) and RTS,S/AS02(D) in children aged 5-17 months in two research centers in Ghana. Control Rabies vaccine using the 0,1,2-month schedule was used in one of two study sites. RESULTS: Whole blood antigen stimulation followed by intra-cellular cytokine staining showed RTS,S/AS01(E) induced CSP specific CD4 T cells producing IL-2, TNF-α, and IFN-γ. Higher T cell responses were induced by a 0,1,7-month immunization schedule as compared with a 0,1- or 0,1,2-month schedule. RTS,S/AS01(E) induced higher CD4 T cell responses as compared to RTS,S/AS02(D) when given on a 0,1,7-month schedule. CONCLUSIONS: These findings support further Phase III evaluation of RTS,S/AS01(E). The role of immune effectors and immunization schedules on vaccine protection are currently under evaluation. TRIAL REGISTRATION: ClinicalTrials.gov NCT00360230.

Evaluation of the safety and immunogenicity of the RTS,S/AS01E malaria candidate vaccine when integrated in the expanded program of immunization.

BACKGROUND: The RTS,S/AS01(E) malaria candidate vaccine is being developed for immunization of African infants through the Expanded Program of Immunization (EPI). METHODS: This phase 2, randomized, open, controlled trial conducted in Ghana, Tanzania, and Gabon evaluated the safety and immunogenicity of RTS,S/AS01(E) when coadministered with EPI vaccines. Five hundred eleven infants were randomized to receive RTS,S/AS01(E) at 0, 1, and 2 months (in 3 doses with diphtheria, tetanus, and whole-cell pertussis conjugate [DTPw]; hepatitis B [HepB]; Haemophilus influenzae type b [Hib]; and oral polio vaccine [OPV]), RTS,S/AS01(E) at 0, 1, and 7 months (2 doses with DTPwHepB/Hib+OPV and 1 dose with measles and yellow fever), or EPI vaccines only. RESULTS: The occurrences of serious adverse events were balanced across groups; none were vaccine-related. One child from the control group died. Mild to moderate fever and diaper dermatitis occurred more frequently in the RTS,S/AS01(E) coadministration groups. RTS,S/AS01(E) generated high anti-circumsporozoite protein and anti-hepatitis B surface antigen antibody levels. Regarding EPI vaccine responses upon coadministration when considering both immunization schedules, despite a tendency toward lower geometric mean titers to some EPI antigens, predefined noninferiority criteria were met for all EPI antigens except for polio 3 when EPI vaccines were given with RTS,S/AS01(E) at 0, 1, and 2 months. However, when antibody levels at screening were taken into account, the rates of response to polio 3 antigens were comparable between groups. CONCLUSION: RTS,S/AS01(E) integrated in the EPI showed a favorable safety and immunogenicity evaluation. Trial registration. ClinicalTrials.gov identifier: NCT00436007 . GlaxoSmithKline study ID number: 106369 (Malaria-050).

Randomized controlled trial of RTS,S/AS02D and RTS,S/AS01E malaria candidate vaccines given according to different schedules in Ghanaian children.

BACKGROUND: The target delivery channel of RTS,S candidate malaria vaccines in malaria-endemic countries in Africa is the World Health Organisation Expanded Program on Immunization. As an Adjuvant System, age de-escalation and schedule selection step, this study assessed 3 schedules of RTS,S/AS01(E) and RTS,S/AS02(D) in infants and young children 5-17 months of age in Ghana. METHODOLOGY: A Phase II, partially-blind randomized controlled study (blind to vaccine, not to schedule), of 19 months duration was conducted in two (2) centres in Ghana between August 2006 and May 2008. Subjects were allocated randomly (1:1:1:1:1:1) to one of six study groups at each study site, each defining which vaccine should be given and by which schedule (0,1-, 0,1,2- or 0,1,7-months). For the 0,1,2-month schedule participants received RTS,S/AS01(E) or rabies vaccine at one center and RTS,S/AS01(E) or RTS,S/AS02(D) at the other. For the other schedules at both study sites, they received RTS,S/AS01(E) or RTS,S/AS02(D). The primary outcome measure was the occurrence of serious adverse events until 10 months post dose 1. RESULTS: The number of serious adverse events reported across groups was balanced. One child had a simple febrile convulsion, which evolved favourably without sequelae, considered to be related to RTS,S/AS01(E) vaccination. Low grade reactions occurred slightly more frequently in recipients of RTS,S/AS than rabies vaccines; grade 3 reactions were infrequent. Less local reactogenicity occurred with RTS,S/AS01(E) than RTS,S/AS02(D). Both candidate vaccines were highly immunogenic for anti-circumsporozoite and anti-Hepatitis B Virus surface antigen antibodies. Recipients of RTS,S/AS01(E) compared to RTS,S/AS02(D) had higher peak anti-circumsporozoite antibody responses for all 3 schedules. Three dose schedules were more immunogenic than 2 dose schedules. Area under the curve analyses for anti-circumsporozoite antibodies were comparable between the 0,1,2- and 0,1,7-month RTS,S/AS01(E) schedules. CONCLUSIONS: Both candidate malaria vaccines were well tolerated. Anti-circumsporozoite responses were greater with RTS,S/AS01(E) than RTS,S/AS02(D) and when 3 rather than 2 doses were given. This study supports the selection of RTS,S/AS01(E) and a 3 dose schedule for further development in children and infants. TRIAL REGISTRATION: ClinicalTrials.gov NCT00360230.