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Imelda Bates

Publications and source records attributed to Imelda Bates.

14 recordsLinked to original sources
PubMed2006

Urban malaria and anaemia in children: a cross-sectional survey in two cities of Ghana.

OBJECTIVE: To describe the epidemiology of urban malaria, an emerging problem in sub-Saharan Africa. METHOD: Cross-sectional surveys of communities in Accra and Kumasi, Ghana, determining risk factors for malaria infection and anaemia in children aged 6-60 months. RESULTS: Malaria prevalence rates ranged from 2% to 33% between urban communities. 47.1% of children were anaemic (Hb<11.0 g/dl). Factors associated with malaria prevalence were low socio-economic status, age and anaemia. The attributable risks of anaemia and severe anaemia (Hb<8.0 g/dl) caused by malaria were 5% and 23% respectively. CONCLUSIONS: Malaria in urban areas displayed a heterogeneity and complexity that differed from the rural environment, which has important implications for malaria control. Marked intra-city variation indicates the importance of targeting specific areas or districts. The most vulnerable group, the urban poor, should be prioritized when designing control measures. This would require careful assessment of the malaria risk pattern in any city to guide an integrated control program.

Age Distribution↗
PubMed2005

Investigation of familial segregation of hyperreactive malarial splenomegaly in Kumasi, Ghana.

Hyperreactive malarial splenomegaly (HMS), a common cause of massive splenomegaly in malaria-endemic regions, is defined as persistent splenomegaly without demonstrable underlying disease. Previous studies have found HMS more frequently in certain tribes in Papua New Guinea, Uganda and Nigeria, with strong familial associations in Uganda and Papua New Guinea. This case-control study aimed to determine the extent of familial association of splenomegaly and the pattern of segregation of the condition in families in Ghana. It involved 22 HMS cases with 99 relatives, and 15 population controls of similar socio-economic background with 51 relatives. The pedigree of each family was recorded. Clinical and laboratory data were collected on all participants, including the presence and degree of splenomegaly. Relatives with splenomegaly were identified for 27% of HMS cases and for 6.7% of population controls (P=0.04). There were significant differences in the IgM levels, which were higher (P=0.005), and the haemoglobin levels, which were lower (P=0.009), in cases compared with controls. In Ghana, relatives of HMS cases are more likely to have splenomegaly than population controls, but with no obvious pattern of Mendelian segregation. HMS aetiology in Ghana is likely to be complex, involving multiple genetic and environmental factors.

Adult↗
PubMed2005

Haemoglobin colour scale for anaemia diagnosis where there is no laboratory: a systematic review.

BACKGROUND: Anaemia is a major public health problem, in poor countries most of the cases are diagnosed clinically. This is inaccurate and the haemoglobin colour scale (HCS) has been developed as an inexpensive, simple alternative for assessing anaemia. Laboratory and community studies have assessed its diagnostic accuracy, but controversy over its validity and usefulness remains. We carried out a systematic review to identify and summarize studies, explain heterogeneity, and make recommendations for future research. METHODS: We searched electronic databases (MEDLINE, EMBASE, CINAHL, and Science Citation Index), checked documents and references, and contacted experts. We included all the studies comparing HCS diagnostic accuracy with a reference standard. Both reviewers independently screened titles and abstracts, assessed studies for inclusion, appraised quality, and extracted data. RESULTS: We included 14 studies, mostly from sub-Saharan Africa. Studies had heterogeneous populations, health care settings, anaemia prevalence, and findings. HCS sensitivity for detecting anaemia was high in most of the studies (75-97%); specificity was generally lower (41-98%). Sensitivity and specificity were higher for laboratory-based studies compared with more pragmatic 'real-life' studies, and the 'study setting' appeared to explain some of the heterogeneity. Five studies compared the HCS with clinical diagnosis; sensitivity was higher for the HCS in four studies, but specificity was often higher with clinical diagnosis. A few studies evaluated the HCS in situations where there was no laboratory. CONCLUSIONS: The HCS may improve anaemia diagnosis where there is no laboratory, but there is a need for policy-relevant diagnostic research which is pragmatic, implementation-focused and assesses clinical outcomes. This requires a different approach and research skill-mix from efficacy studies.

Anemia↗
PubMed2005

Malaria and urbanization in sub-Saharan Africa.

There are already 40 cities in Africa with over 1 million inhabitants and the United Nations Environmental Programme estimates that by 2025 over 800 million people will live in urban areas. Recognizing that malaria control can improve the health of the vulnerable and remove a major obstacle to their economic development, the Malaria Knowledge Programme of the Liverpool School of Tropical Medicine and the Systemwide Initiative on Malaria and Agriculture convened a multi-sectoral technical consultation on urban malaria in Pretoria, South Africa from 2nd to 4th December, 2004. The aim of the meeting was to identify strategies for the assessment and control of urban malaria. This commentary reflects the discussions held during the meeting and aims to inform researchers and policy makers of the potential for containing and reversing the emerging problem of urban malaria.

Africa South of the Sahara↗
PubMed2004

Improving the accuracy of malaria-related laboratory tests in Ghana.

BACKGROUND: Inaccurate malaria results can lead to patient mismanagement, misperceptions about malaria resistance patterns and public health misinformation. All laboratories need to be able to demonstrate that their results are accurate. Establishing and maintaining a system for monitoring test accuracy is a complex, expensive and technically demanding process, which very few poor countries have been able to implement. This study described the process and assessed the feasibility of establishing a nation-wide system for improving the accuracy of malaria-related tests in peripheral laboratories in Ghana. PROGRAMME IMPLEMENTATION: A baseline survey of all 693 laboratory staff in 205 sub-regional government and mission health laboratories in Ghana was conducted by a national network of laboratory supervisors. Survey results guided a training programme to improve test accuracy. Outcomes included changes in the quality of laboratory tests and the system was considered to be feasible if >50% of laboratory staff in each region received training and if test accuracy could be documented. PROGRAMME INDICATORS: 74% (mean) of the 693 laboratory staff were assistants with no professional qualifications. There were marked differences between regions in the availability of essential resources for malaria diagnosis (e.g. microscopes). 93% of laboratory staff received training; in six months there were increases of 11% and 7% respectively in the number of laboratories producing haemoglobin and malaria microscopy results of acceptable quality. CONCLUSIONS: It is possible to establish a system for improving and monitoring test accuracy in peripheral laboratories on a country-wide basis in a developing country using a model that could be adapted for use in other countries and for other components of health care provision.

Clinical Laboratory Techniques↗
PubMed2004

Vulnerability to malaria, tuberculosis, and HIV/AIDS infection and disease. Part 1: determinants operating at individual and household level.

A high burden of malaria, tuberculosis, and HIV infection contributes to national and individual poverty. We have reviewed a broad range of evidence detailing factors at individual, household, and community levels that influence vulnerability to malaria, tuberculosis, and HIV infection and used this evidence to identify strategies that could improve resilience to these diseases. This first part of the review explores the concept of vulnerability to infectious diseases and examines how age, sex, and genetics can influence the biological response to malaria, tuberculosis, and HIV infection. We highlight factors that influence processes such as poverty, livelihoods, gender discrepancies, and knowledge acquisition and provide examples of how approaches to altering these processes may have a simultaneous effect on all three diseases.

Communicable Disease Control↗
PubMed2004

Vulnerability to malaria, tuberculosis, and HIV/AIDS infection and disease. Part II: Determinants operating at environmental and institutional level.

This review summarises a wide range of evidence about environmental and institutional factors that influence vulnerability to malaria, tuberculosis, and HIV infection. By combining this information with that obtained on factors operating at individual, household, and community level, we have identified potential common strategies for improving resilience to all three diseases simultaneously. These strategies depend on collaborations with non-health sectors and include progress in rapid access to funds, provision of education about disease transmission and management, reduction of the burden on carers (predominantly women), and improvement in the quality of health services.

Communicable Disease Control↗
PubMed2002

Causes of massive tropical splenomegaly in Ghana.

BACKGROUND: The causes and diagnosis of massive tropical splenomegaly are not well studied, especially with modern investigative methods. We aimed to identify features that would help local clinicians differentiate between the underlying conditions. METHODS: We collected prospective clinical and laboratory data on 221 Ghanaian patients with spleen size of at least 10 cm. We identified conditions associated with massive splenomegaly with molecular and immunological investigations as well as routine tests. Patients were assigned to diagnostic categories on the basis of these test results and predetermined criteria. FINDINGS: Hyper-reactive malarial splenomegaly (HMS; 91 patients [41%]) and B-lymphoproliferative disorders (48 [22%]) were the most common disorders associated with massive splenomegaly. Of the remaining patients, 32 (14%) had haematological disorders, and in 50 (23%) we could not identify the cause of splenomegaly. Male sex predominated in all diagnostic groups except HMS and tropical splenic lymphoma. Age less than 40 years and absolute lymphocyte count (less than 10 x 10(9)/L) were the only useful and widely available discriminators for distinguishing patients with HMS from those with lymphoproliferative disorders. INTERPRETATION: B-lymphoproliferative disorders are a previously unrecognised cause of massive tropical splenomegaly. This finding has major implications for management of massive splenomegaly. Diagnosis of the less common causes of this disorder is usually straightforward, but differentiating between B-lympho proliferative disorders and HMS can be difficult. HMS is associated with younger age, a higher proportion of women, and lower absolute lymphocyte counts than lympho proliferative disorders.

Adolescent↗
PubMedDate not supplied

Malaria misdiagnosis: effects on the poor and vulnerable.

CONTEXT: Effective and affordable treatment is recommended for all cases of malaria within 24 h of the onset of illness. Most cases of "malaria" (ie, fever) are self-diagnosed and most treatments, and deaths, occur at home. The most ethical and cost-effective policy is to ensure that newer drug combinations are only used for true cases of malaria. Although it is cost effective to improve the accuracy of malaria diagnosis, simple, accurate, and inexpensive methods are not widely available, particularly in poor communities where they are most needed. STARTING POINT: In a recent study in Uganda, Karin Kallander and colleagues emphasise the difficulty in making a presumptive diagnosis of malaria, and highlight the urgent need for improved diagnostic tools that can be used at community and primary-care level, especially in poorer populations (Acta Trop 2004; 90: 211-14). WHERE NEXT? Health systems need strengthening at referral and community level, so that rapid accurate diagnosis and effective treatment is available for those who are least able to withstand the consequences of illness. Indirect evidence strongly suggests that misdiagnosis of malaria contributes to a vicious cycle of increasing ill-health and deepening poverty. Much better direct evidence is needed about why and how misdiagnosis affects the poor and vulnerable.

Antimalarials↗