Kwadwo A. Koram

To estimate the reference intervals for commonly used blood haematology and biochemical parameters in an adult (18–55yrs) population of residents of Mampong Akuapem. This was a population based cross sectional study of a randomly selected sample of the adult population of Mampong. The sample was selected from an updated census list of the Mampong area. Median values (95% range) for measured parameters were established as follows: Haemoglobin, (males) 14.2 g/dl (females) 12.0 g/dl Alanine aminotransferase (ALT), (female) 19.6 U/L (males) 26.1 U/L and Creatinine, (males) 108 mmol/L (females) 93 mmol/L. In comparison to reference values that are commonly used in Ghana, the haemoglobulin levels from this study were lower, and liver function parameters higher. This could be a result of genetic or environmental differences and calls for the need to establish site specific reference values applicable to our population

The individual informed consent model remains critical to the ethical conduct and regulation of research involving human beings. Parental informed consent process in a rural setting of northern Ghana was studied to describe comprehension and retention among parents as part of the evaluation of the existing informed consent process.

Severe falciparum malaria in children was studied as part of the characterization of the Kassena-Nankana District Ghana for future malaria vaccine trials. Children aged 6-59 months with diagnosis suggestive of acute disease were characterized using the standard WHO definition for severe malaria. Of the total children screened, 45.2% (868/1921) satisfied the criteria for severe malaria. Estimated incidence of severe malaria was 3.4% (range: 0.4-8.3%) cases per year. The disease incidence was seasonal: 560 cases per year, of which 70.4% occurred during the wet season (June-October). The main manifestations were severe anaemia (36.5%); prolonged or multiple convulsions (21.6%); respiratory distress (24.4%) and cerebral malaria (5.4%). Others were hyperpyrexia (11.1%); hyperparasitaemia (18.5%); hyperlactaemia (33.4%); and hypoglycaemia (3.2%). The frequency of severe anaemia was 39.8% in children of six to 24 months of age and 25.9% in children of 25-60 months of age. More children (8.7%) in the 25-60 months age group had cerebral malaria compared with 4.4% in the 6-24 months age group. The overall case fatality ratio was 3.5%. Cerebral malaria and hyperlactataemia were the significant risk factors associated with death. Severe anaemia, though a major presentation, was not significantly associated with risk of death. Severe malaria is a frequent and seasonal childhood disease in northern Ghana and maybe an adequate endpoint for future malaria vaccine trials.

Background: Malaria, both with or without convulsions, is a serious hardship for people living in endemic areas, especially in sub-Saharan Africa. Community references to malaria, however, may encompass other conditions, which was collectively designated malaria-related illness (MRI). Inasmuch as the presence or absence of convulsions reportedly affects timely help-seeking for malaria, a local comparison of these conditions is needed to inform malaria control. Methods: Vignette-based EMIC interviews (insider-perspective interviews) for MRI with convulsions (convulsion positive, MRI-CP) and without convulsions (convulsion negative, MRI-CN) were developed to study relevant features of MRI-related experience, meaning and behaviour in two rural communities in Ghana. These semi-structured interviews elicited both qualitative narrative and categorical codes for quantitative analysis. Interviews with 201 respondents were conducted. Results: The conditions depicted in the vignettes were well recognized by respondents and named with various local terms. Both presentations were considered serious, but MRI-CP was more frequently regarded potentially fatal than MRI-CN. More than 90.0% of respondents in both groups acknowledged the need to seek outside help. However, significantly more respondents advised appropriate help-seeking within 24 (p = 0.01) and 48 (p = 0.01) hours for MRI-CP. Over 50.0% of respondents responding to questions about MRI-CP identified MRI-CN as a cause of convulsions. Conclusion: Local comparison of MRI-CP and MRI-CN based on vignettes found a similar profile of reported categories of perceived causes, patterns of distress, help-seeking and preventive measures for both presentations. This differs from previous findings in sub-Saharan Africa, which assert communities regard the two conditions to be unrelated. The perceived relationships should be acknowledged in formulating strategies to control malaria through timely help-seeking and treatment to reduce childhood mortality.

Chloroquine remains the first line antimalarial drug in Ghana. However, the emergence of Plasmodium falciparum resistance to chloroquine is a major obstacle to the national control strategy of case management. This study provides information on some of the reasons underlying chloroquine treatment failure in the country. Household surveys, using multi-stage sampling, were conducted in 2 sentinel districts, Wassa West and Kassena Nankana, established to monitor chloroquine resistance in the country. Five hundred caregivers were interviewed in each district to determine patterns of antimalarial drug use among caregivers of children under 10 years. Inventory on home-kept drugs was conducted. Two hundred and four households in the Wassa West district kept a cumulative total of 248 drugs, whereas 228 households in the Kassena Nankana district kept a cumulative total of 410 drugs. One hundred and ninety-nine (80.2%) of the drugs kept in the Wassa West district and 181 (44.2%) of drugs kept in the Kassena Nankana district were antimalarials. The most commonly kept antimalarial drug in homes was chloroquine (88% and 96% in the Wassa West and Kassena Nankana districts respectively). Reasons given for keeping antimalarials were mainly "leftover after previous treatment". Caregivers' descriptions of the amount of chloroquine given to family members suspected to have malaria within the 2-week period preceding the survey were mostly inappropriate in the 2 districts. However, the proportion of appropriateness of doses was significantly lower in the Wassa West district (11.1% vs 36.4%; p < 0.0001). The significantly higher proportion of inappropriateness of chloroquine use in the Wassa West district could be a factor influencing the lower sensitivity of Plasmodium falciparum to chloroquine in the district compared to the Kassena Nankana district.

We studied the malaria transmission dynamics in Kassena Nankana district (KND), a site in northern Ghana proposed for testing malaria vaccines. Intensive mosquito sampling for 1 year using human land...

We compared the VecTest^TM dipstick assay for detection of Plasmodium sporozoites in Anopheles vectors of malaria with standard circumsporozoite (CS) microplate ELISA for detection of Plasmodium falciparum circumsporozoite protein (PfCSP) in Anopheles mosquitoes. Mosquitoes were collected from a malaria endemic site (Kassena Nankana district) in northern Ghana. Of 2620 randomly sampled mosquitoes tested, the standard CS‐ELISA gave a sporozoite rate of 10.8% compared with 11.2% by VecTest^TM, which was not statistically different (P = 0.66). Visual reading of the CS‐ELISA results gave a sporozoite rate of 13.4%, which was higher than the other tests (P > 0.05). To allow a more objective evaluation of the sensitivity of the dipstick, an additional 136 known CS‐ELISA‐positive specimens were analysed. The prevalence of the test (including the additional samples) was 14.6% and 14.7% for CS‐ELISA and dipstick, respectively (P > 0.05). The estimated prevalence by visual assessment of the CS‐ELISA results was 17.5%. The relative specificity and sensitivity of the VecTest^TM dipstick and visually read ELISA were estimated based on the CS‐ELISA as a gold standard. The specificities of the dipstick and visual ELISA were high, 98.0% and 96.6%, respectively. However, the sensitivities of the two assays were 88.8% for VecTest and 100% for visual ELISA (P < 0.01). Concordance between VecTest and CS‐ELISA was good (κ = 0.86). Similarly, there was a good concordance between the dipstick and the visually read ELISA (κ = 0.88). Extrapolating from PfCSP controls (titrated quantities of P. falciparum sporozoites), mean sporozoite loads of CS‐ELISA‐positive An. gambiae (286 ± 28.05) and An. funestus (236 ± 19.32) were determined (P = 0.146). The visual dipstick grades showed high correlation with sporozoite load. The more intense the dipstick colour, the higher the mean sporozoite load (+ = 108, ++ = 207, +++ = 290, r = 0.99, r² = 1). The VecTest dipstick offers practical advantages for field workers needing rapid and accurate means of detection of sporozoites in mosquitoes.

Summary We conducted all‐age point prevalence surveys to profile the severity and seasonality of malaria and anaemia in Kassena‐Nankana District of northern Ghana. Random cross‐sectional surveys were timed to coincide with the end of low (May 2001) and high (November 2001) malaria transmission seasons and to yield information as to the potential value of haemoglobin (Hb) levels and parasitaemia as markers of malaria morbidity and/or malaria vaccine effect. Parasitaemia was found in 22% (515 of 2286) screened in May (dry‐low transmission), and in 61% of the general population (1026 of 1676) screened in November (wet‐high transmission). Malaria prevalence in May ranged from 4% (infants vs. high, 5.4%; P = 0.52) and greatly reduced from levels measured in this same community and age group in November 2000 (12.5%) and November 1996 (22.0%). Despite the lower frequency of anaemia/SA in young children surveyed in 2001, it was still clear that this condition was strongly associated with parasitaemia and that children under 5 years of age experienced a significant drop in their mean Hb levels by the end of the high transmission season. Prevalence of parasitaemia was significantly lower (P < 0.01) among infants and young children (<2 years) whose parents reported the use of bednets. There was a significantly lower risk of parasitaemia among infants [odds ratio (OR) 6–8] and young children (OR 3–4) living in the central, more urbanized sector of the study area.

Malaria and anemia accounted for 41% and 18% respectively of hospital deaths in the Kassena-Nankana district of northern Ghana during 1996. We measured hemoglobin (Hb), malaria prevalence, and anthropometric indices of 6--24-month-old infants and young children randomly selected from this community at the end of the high (May-October, n = 347) and low (November-April, n = 286) malaria transmission seasons. High transmission season is characterized by rainfall (the equivalent of 800-900 mm/yr.), while the remaining months receive less than 50 mm/yr. Severe anemia, defined as Hb < 6.0 g/dL, was 22.1% at the end of the high transmission season compared to 1.4% at the end of the low transmission season (Odds Ratio [OR] = 20.1; 95% CI: 7.1-55.3). Parasitemia was 71% and 54.3% at these time points (OR = 2.1; 95% CI: 1.5-2.9). Nutritional anemia appeared to have little impact upon this seasonal difference since anthropometric indices were comparable. Although the relative contributions of other causes of severe anemia were not assessed, repeated malaria infections may be a primary determinant of severe anemia among infants and young children during the high transmission season.