Sam Newton

Epidemiology of malaria in the forest-savanna transitional zone of Ghana

BackgroundInformation on the epidemiology of malaria is essential for designing and interpreting results of clinical trials of drugs, vaccines and other interventions. As a background to the establishment of a site for anti-malarial drugs and vaccine trials, the epidemiology of malaria in a rural site in central Ghana was investigated.MethodsActive surveillance of clinical malaria was carried out in a cohort of children below five years of age (n = 335) and the prevalence of malaria was estimated in a cohort of subjects of all ages (n = 1484) over a 12-month period. Participants were sampled from clusters drawn around sixteen index houses randomly selected from a total of about 22,000 houses within the study area. The child cohort was visited thrice weekly to screen for any illness and a blood slide was taken if a child had a history of fever or a temperature greater than or equal to 37.5 degree Celsius. The all-age cohort was screened for malaria once every eight weeks over a 12-month period. Estimation of Entomological Inoculation Rate (EIR) and characterization of Anopheline malaria vectors in the study area were also carried out.ResultsThe average parasite prevalence in the all age cohort was 58% (95% CI: 56.9, 59.4). In children below five years of age, the average prevalence was 64% (95% CI: 61.9, 66.0). Geometric mean parasite densities decreased significantly with increasing age. More than 50% of all children less than 10 years of age were anaemic. Children less than 5 years of age had as many as seven malaria attacks per child per year. The attack rates decreased significantly with increasing cut-offs of parasite density. The average Multiplicity of Infection (MOI) was of 6.1. All three pyrimethamine resistance mutant alleles of the Plasmodium falciparum dhfr gene were prevalent in this population and 25% of infections had a fourth mutant of pfdhps-A437G. The main vectors were Anopheles funestus and Anopheles gambiae and the EIR was 269 infective bites per person per year.ConclusionThe transmission of malaria in the forest-savanna region of central Ghana is high and perennial and this is an appropriate site for conducting clinical trials of anti-malarial drugs and vaccines.

Timing of initiation patterns of breastfeeding and infant survival: prospective analysis of pooled data from three randomised trials.

BACKGROUND Although the benefits of exclusive breastfeeding for child health and survival, particularly in the post-neonatal period, are established, the independent beneficial effect of early breastfeeding initiation remains unclear. We studied the association between timing of breastfeeding initiation and post-enrolment neonatal and post-neonatal mortality up to 6 months of age, as well as the associations between breastfeeding pattern and mortality. METHODS We examined associations between timing of breastfeeding initiation, post-enrolment neonatal mortality (enrolment 28 days), and post-neonatal mortality up to 6 months of age (29-180 days) in a large cohort from three neonatal vitamin A trials in Ghana, India, and Tanzania. Newborn babies were eligible for these trials if their mother reported that they were likely to stay in the study area for the next 6 months, they could feed orally, were aged less than 3 days, and the primary caregiver gave informed consent. We excluded infants who initiated breastfeeding after 96 h, did not initiate, or had missing initiation status. We pooled the data from both randomised groups of the three trials and then categorised time of breastfeeding initiation as: at ≤1 h, 2-23 h, and 24-96 h. We defined breastfeeding patterns as exclusive, predominant, or partial breastfeeding at 4 days, 1 month, and 3 months of age. We estimated relative risks using log binomial regression and Poisson regression with robust variances. Multivariate models controlled for site and potential confounders. FINDINGS Of 99 938 enrolled infants, 99 632 babies initiated breastfeeding by 96 h of age and were included in our prospective cohort. 56 981 (57·2%) initiated breastfeeding at ≤1 h, 38 043 (38·2%) at 2-23 h, and 4608 (4·6%) at 24-96 h. Compared with infants initiating breastfeeding within the first hour of life, neonatal mortality between enrolment and 28 days was higher in infants initiating at 2-23 h (adjusted relative risk 1·41 [95% CI 1·24-1·62], p<0·0001), and in those initiating at 24-96 h (1·79 [1·39-2·30], p<0·0001). These associations were similar when deaths in the first 4 days of life were excluded (1·32 [1·10-1·58], p=0·003, for breastfeeding initiation at 2-23 h, and 1·90 [1·38-2·62], p=0·0001, for initiation at 24-96 h). When data were stratified by exclusive breastfeeding status at 4 days of age (p value for interaction=0·690), these associations were also similar in magnitude but with wider confidence intervals for initiation at 2-23 h (1·41 [1·12-1·77], p=0·003) and for initiation at 24-96 h (1·51 [0·63-3·65], p=0·357). Exclusive breastfeeding was also associated with the lower mortality during the first 6 months of life (1-3 months mortality: exclusive vs partial breastfeeding at 1 month 1·83 [1·45-2·32], p<0·0001, and exclusive breastfeeding vs no breastfeeding at 1 month 10·88 [8·27-14·31], p<0·0001). INTERPRETATION Our findings suggest that early initiation of breastfeeding reduces neonatal and early infant mortality both through increasing rates of exclusive breastfeeding and by additional mechanisms. Both practices should be promoted by public health programmes and should be used in models to estimate lives saved. FUNDING Bill & Melinda Gates Foundation through a grant to the WHO.

Effect of early neonatal vitamin A supplementation on mortality during infancy in Ghana (Neovita): a randomised, double-blind, placebo-controlled trial

BACKGROUND Results of randomised controlled trials of newborn (age 1-3 days) vitamin A supplementation have been inconclusive. The WHO is coordinating three large randomised trials in Ghana, India, and Tanzania (Neovita trials). We present the findings of the Neovita trial in Ghana. METHODS This study was a population-based, individually randomised, double-blind, placebo-controlled trial in the Brong Ahafo region of Ghana. The trial participants were infants aged at least 2 h, identified at home or facilities on the day of birth or in the next 2 days, able to feed orally, and likely to stay in the study area for at least 6 months. They were randomly assigned (ratio 1:1) to receive either one oral dose of vitamin A (50,000 IU) or placebo immediately after recruitment. The research team and parents of the infants were masked to treatment assignment. Follow-up home visits were undertaken every 4 weeks, when data were recorded for deaths, facility use, and care seeking. The primary outcome was post-supplementation mortality to 6 months of age. Analysis was by intention to treat. Potential adverse events were recorded at 1 and 3 days after supplementation. This trial is registered with the Australian New Zealand Clinical Trials Registry (ANZCTR)CTRN12610000582055. FINDINGS We assessed 26,414 livebirths for eligibility between Aug 16, 2010, and Nov 7, 2011. We recruited 22,955 newborn infants, with 11,474 randomly assigned to receive vitamin A and 11,481 to receive placebo. Loss to follow-up was low with vital status at 6 months of age reported for 22,698 (98·9%) infants. We recorded 278 post-supplementation deaths to 6 months of age in the vitamin A group (mortality risk 24·5 in 1000 supplemented infants) and 248 deaths in the placebo group (mortality risk 21·8 per 1000 supplemented infants), relative risk (RR) 1·12 (95% CI 0·95-1·33; p=0·183) and risk difference (RD) 2·66 (95% CI -1·25 to 6·57; p=0·18). Adverse events within 3 days of supplementation did not differ by trial group. 122 infants died in the first 3 days after supplementation; 70 (0·6%) in the vitamin A and 52 (0·5%) in the placebo group (risk ratio [RR] 1·35, 95% CI 0·94-1·93, p=0·102). 53 infants were reported to have a bulging fontanelle; 32 (0·3%) in the vitamin A group and 21 (0·2%) in the placebo group (RR 1·53, 0·88-2·62, p=0·130). INTERPRETATION The results of this trial do not support inclusion of newborn vitamin A supplementation as a child survival strategy in Ghana. FUNDING Bill & Melinda Gates Foundation grant to the WHO.

Efficacy of Early Neonatal Vitamin A Supplementation in Reducing Mortality During Infancy in Ghana, India and Tanzania: Study Protocol for a Randomized Controlled Trial

BackgroundVitamin A supplementation of 6-59 month old children is currently recommended by the World Health Organization based on evidence that it reduces mortality. There has been considerable interest in determining the benefits of neonatal vitamin A supplementation, but the results of existing trials are conflicting. A technical consultation convened by WHO pointed to the need for larger scale studies in Asia and Africa to inform global policy on the use of neonatal vitamin A supplementation. Three trials were therefore initiated in Ghana, India and Tanzania to determine if vitamin A supplementation (50,000 IU) given to neonates once orally on the day of birth or within the next two days will reduce mortality in the period from supplementation to 6 months of age compared to placebo.Methods/DesignThe trials are individually randomized, double masked, and placebo controlled. The required sample size is 40,200 in India and 32,000 each in Ghana and Tanzania. The study participants are neonates who fulfil age eligibility, whose families are likely to stay in the study area for the next 6 months, who are able to feed orally, and whose parent(s) provide informed written consent to participate in the study. Neonates randomized to the intervention group receive 50,000 IU vitamin A and the ones randomized to the control group receive placebo at the time of enrolment. Mortality and morbidity information are collected through periodic home visits by a study worker during infancy. The primary outcome of the study is mortality from supplementation to 6 months of age. The secondary outcome of the study is mortality from supplementation to 12 months of age. The three studies will be analysed independent of each other. Subgroup analysis will be carried out to determine the effect by birth weight, sex, and timing of DTP vaccine, socioeconomic groups and maternal large-dose vitamin A supplementation.DiscussionThe three ongoing studies are the largest studies evaluating the efficacy of vitamin A supplementation to neonates. Policy formulation will be based on the results of efficacy of the intervention from the ongoing randomized controlled trials combined with results of previous studies.Trial RegistrationGhana: Australian New Zealand Clinical Trials Registry (ANZCTR) - ACTRN12610000582055; India: CLINICALTRIALS.GOV - NCT01138449; Tanzania: Australian New Zealand Clinical Trials Registry (ANZCTR) - ACTRN12610000636055.

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.

Estimating malaria parasite density: assumed white blood cell count of 10,000/μl of blood is appropriate measure in Central Ghana

BackgroundWhite blood cells count (WBCc) is a bedrock in the estimation of malaria parasite density in malaria field trials, interventions and patient management. White blood cells are indirectly and relatively used in microscopy to estimate the density of malaria parasite infections. Due to frequent lack of facilities in some malaria-endemic countries, in order to quantify WBCc of patients, an assumed WBCc of 8.0 X 10(9)/L has been set by the World Health Organization to help in estimating malaria parasite densities.MethodsThis comparative analysis study, in Central Ghana, compiled laboratory data of 5,902 Plasmodium falciparum malaria parasite positive samples. Samples were obtained from consented participants of age groups less than five years. Full blood counts (FBC) of participants’ samples were analysed using the ABX Micros 60 Haematology Analyzer. Blood slides were read by two competent microscopists to produce concordant results. All internal and external quality control measures were carried out appropriately. Parasite densities were calculated using participants’ absolute WBCc and assumed WBCc of 5,000 to 10,000 per microlitre of blood.ResultsFrom the 5,902 Pf malaria positive samples, the mean (SD) WBCc and geometric mean parasite density were 10.4 (4.6) × 10(9)/L and 7,557/μL (95 % CI 7,144/μL to 7,994/μL) respectively. The difference in the geometric mean parasite densities calculated using absolute WBCs and compared to densities with assumed WBCs counts were significantly lower for 5.0 × 10(9)/L; 3,937/μL, 6.0 × 10(9)/L; 4,725/μL and 8.0 × 10(9)/L; 6,300/μL. However, the difference in geometric mean parasite density, 7,874/μL (95 % CI, 7,445/μL to 8,328/μL), with assumed WBCc of 10.0 × 10(9)/L was not significant.ConclusionUsing the assumed WBCc of 8.0 X 10(9)/L or lower to estimate malaria parasite densities in Pf infected children less than five years old could result in significant underestimation of parasite burden. Assumed WBCc of 10.0 × 10(9)/L at 95 % CI of geometric mean of parasite density statistically agreed with the parasite densities produce by the absolute WBCc of participants. The study suggests where resources are limited, use of assumed WBCc of 10.0 × 10(9)/L of blood to estimate malaria parasite density in central Ghana. Preferably, absolute WBCc should be used in drug efficacy and vaccine trials.

Drawing blood from young children: lessons learned from a trial in Ghana.

This paper reflects on lessons learned from a trial in Ghana assessing the impact of vitamin A supplementation on childrens immune responses to tetanus and polio vaccines. There were more losses to follow-up than was anticipated at visits during which blood was drawn, owing to concerns or misconceptions about blood draw. The trial initially planned to recruit 960 children but had to recruit more because the proportion of infants lost to follow-up was greater than the anticipated 15%, resulting in a longer recruitment period. Of 1085 infants who were randomised into the trial, 767 (71%) completed follow-up at 6 months of age. It was notable that at the first (6 weeks) and fourth (6 months) visits at which blood was drawn, losses to follow-up were greater than at the second (10 weeks) and third (14 weeks) visits during which blood was not drawn. Losses to follow-up pose a threat to the validity of trials as there is a chance that those lost to follow-up may differ from those who remain in the trial. Monitoring losses to follow-up as they emerged and allowing mothers to witness the blood draw, as well as holding community meetings, helped to allay anxieties in the community.

Cumulative effects of heat exposure and storage conditions of Oxytocin-in-Uniject in rural Ghana: implications for scale up.

Oxytocin-in-Uniject devices could be stored 30 to 40 days without refrigeration under typical field conditions, with wastage levels below 10%, based on simulation studies. Oxytocin-in-Uniject devices could be stored 30 to 40 days without refrigeration under typical field conditions, with wastage levels below 10%, based on simulation studies. ABSTRACT Objective: Postpartum hemorrhage can be reduced substantially in home deliveries attended by community-based workers by using Oxytocin-in-Uniject (OIU) devices affixed with temperature-time indicators. We characterized the distribution of time to discard of these devices when stored under normal field conditions in Ghana. Methods: Two drug storage simulation studies were conducted in rural Ghana in 2011 and 2012. Devices were transported under refrigeration from manufacture (Argentina) to storage at the study site. Twenty-three field workers each stored at home (unrefrigerated) 25 OIU devices and monitored them daily to record: (1) time to transition from usable to unusable, and (2) continuous digital ambient temperature to determine heat exposure over the simulation period. Time to discard was estimated and compared with mean kinetic temperature exposure of the devices during the shipment and storage phases and with characteristics of the storage locations using Weibull regression models. We used the time to discard distributions in a Monte Carlo simulation to estimate wastage rates in a hypothetical program setting. Results: Time for shipment and transfer to long-term refrigerated storage and mean kinetic temperature during the shipment phase was 8.6 days/10.3°C and 13.4 days/12.1°C, for the first and second simulation studies, respectively. Median (range) time to discard when stored under field conditions (unrefrigerated) was 43 (6 to 59) days and 33 (14 to 50) days, respectively. Mean time to discard was 10.0 days shorter in the second simulation, during which mean kinetic temperature exposure was 3.9°C higher. Simulating a monthly distribution system and assuming typical usage, predicted wastage of product was less than 10%. Conclusion: The time to discard of devices was highly sensitive to small changes in temperature exposure. Under field conditions typical in rural Ghana, OIU packages will have a half-life of approximately 30 to 40 days based on the temperature monitor used during the study. Program managers will need to carefully consider variations in both ambient temperature and rate of use to allocate the appropriate supply level that will maximize coverage and minimize stock loss.

An assessment of the likely acceptability of vaginal microbicides for HIV prevention among women in rural Ghana.

BackgroundThe findings of the CAPRISA tenofovir studies have raised expectations that soon an approved microbicide would be available. However it is in only a limited number of countries in sub-Saharan Africa that the acceptability of microbicides has been evaluated. We conducted a study to assess the acceptability of vaginal microbicides among women in rural Ghana.MethodsThe study employs a mixed method design, using cross-sectional survey and focus group discussions to further understand issues related to awareness and attitudes towards microbicide development, acceptability and perceived partner attitudes among pregnant women attending antenatal clinic in two health facilities in the Kintampo North municipality of Ghana. We used logistic regression to identify possible predictors of microbicide acceptability among the women surveyed.ResultsAlthough only 2% of the 504 women were aware of the development of microbicides, 95% were willing to use one when it became available. The cost of a microbicide that will be considered affordable to 50% of women was US

mPneumonia, an Innovation for Diagnosing and Treating Childhood Pneumonia in Low-Resource Settings: A Feasibility, Usability and Acceptability Study in Ghana.

0.75. Although there were concerns about possible wetting effect, gel or creams were the most preferred (68% of women) formulation. Although 71% thought their partners will find microbicide acceptable, apprehensions about the feasibility of and consequences of failed discreet use were evident. 49% of women were concerned about possible negative effect of microbicide on sexual pleasure. Perceived partner acceptability (O.R. =17.7; 95%C.I. 5.03-62.5) and possibility of discreet use (O.R. =8.9 95%C.I. 2.63-30.13) were the important predictors of microbicide acceptability.ConclusionAchieving microbicide acceptability among male partners should be made a part of the promotive interventions for ensuring effective use among women in rural Ghana.