Showing papers in "Tropical Medicine & International Health in 2000"
TL;DR: The issues addressed below include what has driven the LF Elimination Programme to this point, what will be required to sustain its momentum, and what will its impact be.
Abstract: Ten years ago, no one foresaw that in the year 2000 there would be a Global Programme to Eliminate Lymphatic Filariasis (GPELF) that is already 2 years old, active in 18 of the 80 endemic countries, and operating under a wholly new paradigm in public health - a paradigm affirming that public/private sector partnerships are essential in sharing both responsibilities and responses to global health problems. What has driven the LF Elimination Programme to this point? Where it is now headed? What will be required to sustain its momentum? What will its impact be? These are the issues addressed below.
567 citations
TL;DR: It is hypothesize that any behaviours which prevent stools from getting into the domestic arena, the child's main habitat, are likely to have a greater impact on health than those practices which prevent pathogens in the environment from being ingested.
Abstract: Improving domestic hygiene practices is potentially one of the most effective means of reducing the global burden of diarrhoeal diseases in children. However, encouraging behaviour change is a complex and uncertain business. If hygiene promotion is to succeed, it needs to identify and target only those few hygiene practices which are the major source of risk in any setting. Using biological reasoning, we hypothesize that any behaviours which prevent stools from getting into the domestic arena, the child's main habitat, are likely to have a greater impact on health than those practices which prevent pathogens in the environment from being ingested. Hence safe stool disposal, a primary barrier to transmission, may be more important than hand-washing before eating, which constitutes a secondary barrier, for example. We review the epidemiological evidence for the effect of primary and secondary barrier behaviours and suggest that it supports this conclusion. In the absence of local evidence to the contrary, hygiene promotion programmes should give priority to the safe disposal of faecal material and the adequate washing of hands after contact with adult and child stools.
387 citations
TL;DR: It appears that replacement of natural swamp vegetation with agricultural crops has led to increased temperatures, which may be responsible for elevated malaria transmission risk in cultivated areas.
Abstract: As highland regions of Africa historically have been considered free of malaria, recent epidemics in these areas have raised concerns that high elevation malaria transmission may be increasing. Hypotheses about the reasons for this include changes in climate, land use and demographic patterns. We investigated the effect of land use change on malaria transmission in the south-western highlands of Uganda. From December 1997 to July 1998, we compared mosquito density, biting rates, sporozoite rates and entomological inoculation rates between 8 villages located along natural papyrus swamps and 8 villages located along swamps that have been drained and cultivated. Since vegetation changes affect evapotranspiration patterns and, thus, local climate, we also investigated differences in temperature, humidity and saturation deficit between natural and cultivated swamps. We found that on average all malaria indices were higher near cultivated swamps, although differences between cultivated and natural swamps were not statistically significant. However, maximum and minimum temperature were significantly higher in communities bordering cultivated swamps. In multivariate analysis using a generalized estimating equation approach to Poisson regression, the average minimum temperature of a village was significantly associated with the number of Anopheles gambiae s.l. per house after adjustment for potential confounding variables. It appears that replacement of natural swamp vegetation with agricultural crops has led to increased temperatures, which may be responsible for elevated malaria transmission risk in cultivated areas.
280 citations
TL;DR: To validate the causes of death determined with a single verbal autopsy instrument covering all age groups in the Agincourt subdistrict of rural South Africa.
Abstract: Summaryobjective To validate the causes of death determined with a single verbal autopsy instrument covering all age groups in the Agincourt subdistrict of rural South Africa.
methods Verbal autopsies (VAs) were conducted on all deaths recorded during annual demographic and health surveillance over a 3-year period (1992–95) in a population of about 63 000 people. Trained fieldworkers elicited signs and symptoms of the terminal illness from a close caregiver, using a comprehensive questionnaire written in the local language. Questionnaires were assessed blind by three clinicians who assigned a probable cause of death using a stepwise consensus process. Validation involved comparison of VA diagnoses with hospital reference diagnoses obtained for those who died in a district hospital; and calculation of sensitivity, specificity and positive predictive value (PPV) for children under 5 years, and adults 15 years and older.
results A total of 127 hospital diagnoses satisfied the criteria for inclusion as reference diagnoses. For communicable diseases, sensitivity of VA diagnoses among children was 69%, specificity 96%, and PPV 90%; among adults the values were 89, 93 and 76%. Lower values were found for non-communicable diseases: 75, 91 and 86% among children; and 64, 50 and 80% among adults. Most misclassification occurred within the category itself. For deaths due to accidents or violence, sensitivity was 100%, specificity 97%, and PPV 80% among children; and 75, 98 and 60% among adults. Since causes of death were largely age-specific, few differences in sensitivity, specificity and PPV were found for adults and children. The frequency distribution of causes of death based on VAs closely approximated that of the hospital records used for validation.
conclusion VA findings need to be validated before they can be applied to district health planning. In Agincourt, a single verbal autopsy instrument provided a reasonable estimate of the frequency of causes of death among adults and children. Findings can be reliably used to inform local health planning and evaluation.
241 citations
TL;DR: There is an urgent need for international standards and evidence‐based guidelines to provide a framework to assist the process by which decision‐makers in malaria‐endemic countries can make rational choices for antimalarial drug policy change.
Abstract: Chloroquine resistance was first detected in Kenya in 1978 and escalated during the 1980s. Chloroquine remained the treatment of choice for uncomplicated malaria infections until revised guidelines were launched in 1998 despite a plethora of scientific evidence on failure. This review analyses the range and quality of the evidence base that was used to change the drug policy in Kenya from chloroquine to SP and examines the process of consensus building and decision making. Our review illustrates the difficulties in translating sensitivity data with gross geographical, temporal and methodological variations into national treatment policy. The process was complicated by limited options, unknown adverse effects of replacement therapies, cost, as well as limited guidance on factors pertinent to changing the drug policy for malaria. Although > 50% of the studies showed parasitological failures by 1995, there was a general lack of consensus on the principles for assessing drug failures, the inclusion criteria for the study subjects and the relative benefits of parasitological and clinical assessments. A change in international recommendations for assessment of drug efficacy in 1996 from parasitological to clinical response further perplexed the decisions. There is an urgent need for international standards and evidence-based guidelines to provide a framework to assist the process by which decision-makers in malaria-endemic countries can make rational choices for antimalarial drug policy change.
167 citations
TL;DR: Evidence from intervention studies shows that the promotion of face‐washing gave modest gains for intense effort and a pilot study showed that trachoma transmission was reduced in the absence of eye‐seeking flies.
Abstract: Community control of trachoma as a blinding disease is based on the SAFE strategy of Surgery, Antibiotic therapy, Facial cleanliness and Environmental improvement. Surgery and antibiotic therapy currently dominate most programmes. Blindness from trachoma results from frequent infections repeated over many years, so ultimate success requires the reduction of transmission. This is only likely to be sustainable through the F and E components of SAFE. Environmental improvement with access to water, enhanced hygiene and better sanitation reduces trachoma transmission and the blinding sequelae eventually disappear. Transmission routes and factors that cause this are not known and consequently no single specific tool for F and E is in place. Evidence from intervention studies shows that the promotion of face-washing gave modest gains for intense effort and a pilot study showed that trachoma transmission was reduced in the absence of eye-seeking flies. Other studies have shown that latrines and improved access to water are associated with a lower prevalence of active trachoma. There is likely to be a long-term beneficial effect of a combination of improved water supplies, provision of latrines, facial hygiene promotion through established infrastructure and control of eye-seeking flies. Each of these interventions offers additional public health and other benefits in its own right. Further research on the routes of transmission, the role of hygiene and means of sustainable fly control should be a priority.
154 citations
TL;DR: This study shows the feasibility of controlling the incidence of congenitally acquired T. cruzi infections at a province‐wide scale by means of a specific screening programme at first‐line health services level.
Abstract: We designed a set of procedures for first-line local health services to detect and treat the congenital transmission of Trypanosoma cruzi at a province-wide scale, and field-tested the programme in the province of Tucuman, northwestern Argentina, from 1992 to 1994. The programme consists of routine screening of pregnant women for seroreactivity to T. cruzi, serological and parasitological follow-up of the newborn at least twice during the first year of age, treatment of the infected infants, and evaluation of the outcome. 927 (5.5%) of 16 842 pregnant women were seroreactive to T. cruzi by indirect haemagglutination assay and ELISA. Twenty-one (6.7%) of 315 newborns to seroreactive mothers were diagnosed as infected with T. cruzi parasites microhaematocrit concentration before 30 days of age. Five newborns who initially tested negative had a T. cruzi infection detected by microhaematocrit and/or serological techniques at 3 or 6 months of age. Thus, congenital infection was diagnosed in 26 (7.1%) infants born to seroreactive women and residing in houses free of triatomine bugs. Four of 6 infants born to seroreactive mothers died during the first year of age and had some evidence of T. cruzi infection; one of the deaths was attributed to T. cruzi based on clinical evidence. After specific treatment with nifurtimox or benznidazole, 30 of 32 infants remained parasitologically and serologically negative. This study shows the feasibility of controlling the incidence of congenitally acquired T. cruzi infections at a province-wide scale by means of a specific screening programme at first-line health services level.
146 citations
TL;DR: Malaria microscopy is very reliable for the estimation of parasite ratios and geometric mean parasite densities within and between studies as long as the same methodology is used, but tends to underestimate the gametocyte ratio and proportion of mixed infections.
Abstract: To assess the interrater reproducibility of malaria microscopy in epidemiological studies, 711 thick blood films from population-based surveys were randomly selected and reread by 4 experienced microscopists Sample estimates of the prevalence of P falciparum infection, geometric mean parasite density and the proportion of samples above various parasite density cut-off levels were almost identical in the routine and quality control readings Differences were, however, encountered in the sample estimates for gametocyte ratio, proportion of mixed infection and average density index In all three cases the quality control result was significantly higher than the routine evaluation On the level of the individual slide there was good interrater agreement for the presence of P falciparum infections (Kappa index kappa = 079) which was even better when parasite densities between 4 and 100/microl were excluded (kappa = 094) With respect to the assessment of parasite density, a high level of disagreement was found While the mean difference between the two readings was not different from 0, the second reading was between 012 and 10 times that of the first However, the level of disagreement significantly fell with increasing parasite densities Thus malaria microscopy is very reliable for the estimation of parasite ratios and geometric mean parasite densities within and between studies as long as the same methodology is used, but tends to underestimate the gametocyte ratio and proportion of mixed infections Care must be taken, however, when individual parasite density is related to other explanatory variables, due to the high degree of variability in the parasite enumeration
139 citations
TL;DR: It is suggested that improved interpersonal skills of health centre staff and co‐ordination between the private doctors and the health centres may substantially improve services for TB patients.
Abstract: Inefficient case finding is an important stumbling block to successful control of tuberculosis (TB). Multiple health seeking may account for delayed case finding. Health-seeking behaviour, health seeking delay, perceived causes, and perceived quality of care related to TB were studied in interviews with 319 sputum smear-positive TB patients. The patients were treated in 22 governmental health centres of Malabon, a municipality of Metro Manila, Philippines. Only 29% of the respondents had gone first to a health centre after onset of TB-related symptoms, and more than half (53%) had initially consulted a private doctor. A chest X-ray was obtained for nearly everyone (97%). Two thirds of the patients (66%) had received a prescription for drugs, and 29% had purchased and taken anti-TB drugs for at least three weeks before they came to a governmental health centre. Concerning community interactions, 36% said they knew at least one person who had been treated for TB without success. The health seeking delay after symptom onset was relatively short - 64% of the respondents said they went to a health facility within 1 month. Case studies illustrate the rationale for health seeking and explain delayed initiation of appropriate treatment for many patients. Findings underscore the need for and indicate approaches to health communication for improved control of TB. Our findings from interview narratives also suggest that improved interpersonal skills of health centre staff and co-ordination between the private doctors and the health centres may substantially improve services for TB patients.
133 citations
TL;DR: This study aims to investigate antibiotic use and antibiotic susceptibility of respiratory tract pathogens in children aged 1–5 years in Bavi, Vietnam.
Abstract: The aim was to investigate antibiotic use and antibiotic susceptibility of respiratory tract pathogens in children aged 1-5 years in Bavi Vietnam. Nasopharynx and throat specimens were collected from 200 children from randomly selected households in a demographically defined population. Respiratory isolates were tested for antibiotic susceptibility according to the standard disk diffusion method. A questionnaire survey of carers elicited information on type of antibiotics used duration of treatment where the antibiotics had been purchased type of treatment information retained by carers and episodes of illness preceding the study. 82% of the children had at least one symptom of acute respiratory tract infection in the 4 weeks prior to the study and of these 91% were treated with antibiotics. The most commonly used antibiotics were ampicillin (74%) penicillin (12%) amoxicillin (11%) erythromycin (5%) tetracycline (4%) and streptomycin (2%). Ampicillin was used for 3.3 days on average (standard deviation [SD]: 1.8) and penicillin for 2.6 days (SD: 0.7). When deciding which antibiotic to use 67% of the carers consulted the pharmacy seller 11% decided themselves and 22% followed the doctors prescription. The carrier rate of Streptococcus pneumoniae Haemophilus influenzae and Moraxella catarrhalis was 50% 39% and 17% respectively. Isolates from 145 children were susceptibility tested and 74% were found to carry resistant pathogens. Of the tested isolates 90% of S. pneumoniae 68% of H. influenzae and 74% of M. catarrhalis were resistant to at least one antibiotic. The mean number of antibiotics (susceptible strains excluded) to which resistance was found was 2.0 (SD: 1.2) 2.5 (SD: 1.8) and 2.1 (SD: 0.9) respectively. S. pneumoniae and H. influenzae showed high resistance to tetracycline (88% and 32% respectively) trimethoprim/sulphonamide (32% and 44%) and chloramphenicol(25% and 24%). 23% of S. pneumoniae were erythromycin-resistant and 18% of H. influenzae isolates were resistant to ampicillin. There was a significant difference in ampicillin and penicillin resistance between the group of children previously treated with beta lactam antibiotics and the group of children who did not receive antibiotics. As reported by the carers children in Bavi are treated with antibiotics frequently. Most antibiotics were obtained without consulting a doctor. High levels of antibiotic resistance and high prevalence of multidrug-resistant strains were found among respiratory pathogens. The existence of a large reservoir of resistance genes among children in low-income countries represents a threat to the success of antibiotic therapy throughout the world. Multi-faceted programs to improve rational use of antibiotics in Vietnam are urgently needed. (authors)
130 citations
TL;DR: It is argued that pre‐patent infections may account for some of these ‘treatment failures’ and further studies in other endemic settings are needed, with parasitological diagnoses having a high sensitivity.
Abstract: Chemotherapy with praziquantel is the cornerstone of schistosomiasis control. In view of recent concern about tolerance or resistance to praziquantel, monitoring its efficacy in different epidemiological settings is required. We report a study among 253 schoolchildren in an area highly endemic for Schistosoma mansoni in western Cote d'Ivoire. After examining four consecutive stool specimens from each child, the first praziquantel treatment at 60 mg/kg divided into two doses was administered. Four weeks later, stool specimens were again screened over 4 consecutive days and revealed a cure rate of 71.6% and an egg reduction rate of 79.9%. There was a significant association between cure rate and intensity of infection prior to treatment with highest cure rates observed in light infections (P < 0.01). Praziquantel, at a single dose of 40 mg/kg, was again administered 35 days after the first treatment. The overall cure and egg reduction rates increased considerably. The association between cure rate and intensity of infection prior to the second treatment was significant but less pronounced. Twenty-two children remained S. mansoni positive after the two chemotherapy campaigns, and interestingly, many of these were only identified after repeated stool examinations. We argue that pre-patent infections may account for some of these 'treatment failures'. However, further studies in other endemic settings are needed, with parasitological diagnoses having a high sensitivity.
TL;DR: Assessment of mothers' abilities to recognize nonsevere and severe/complicated malaria in children when a child has fever with other physiological and behavioural symptoms associated with malaria found a high proportion of the mothers held the belief that an injection in a child with high fever would precipitate convulsions or death.
Abstract: Prior to an intervention on improving the quality of malaria case management the authors assessed mothers abilities to recognize nonsevere and severe/complicated malaria in children when a child has fever with other physiological and behavioral symptoms associated with malaria. Malaria was mentioned as the commonest febrile illness (94.1%) convulsions the least (11.4%). Fever and enteric symptoms featured as the most important symptoms of childhood malaria at frequencies of 93.5% and 73.8% respectively. The need for laboratory diagnosis was very high (98.3%) the reason being to get accurate diagnosis and treatment (89.4%). Poor outcome of treatment was ascribed to incorrect diagnosis and prescription noncompliance at home and ineffective drugs (62.1%). Most mothers (86.6%) would take antipyretic measures first when a child has fever and subsequently the majority (92.9%) would seek care at a modern health facility. About 50% of the mothers would give traditional treatments for childhood convulsions and wait till the fits ceased before the next action. A high proportion of the mothers (75%) held the belief that an injection in a child with high fever would precipitate convulsions or death. The implications of these findings for chemotherapeutic malaria control in holoendemic areas within the context of the Integrated Management of Childhood Illnesses (IMCI) strategy are discussed. (authors)
TL;DR: This study reports on the toxic activity of extracts from Jatropha curcas L. (Euphorbiaceae) against snails transmitting Schistosoma mansoni and S. mansoni, and suggests this plant could become an affordable and effective component of an integrated approach to schistosomiasis control.
Abstract: Summary The aim of studies on plant molluscicides is to complement methods for controlling snails acting as intermediate hosts of schistosomes. We report on the toxic activity of extracts from Jatropha curcas L. (Euphorbiaceae) against snails transmitting Schistosoma mansoni and S. haematobium. We studied different extracts' effects on infectious larvae, cercariae and miracidia of S. mansoni. Compared to aqueous extract, methanol extract showed the highest toxicity against all tested organisms with LC100-values of 25 p.p.m. for cercariae and the snail Biomphalaria glabrata and 1 p.p.m. for the snails Bulinus truncatus and B. natalensis. Attenuation of cercariae leading to reduced infectivity in mice could be achieved in concentrations below those exerting acute toxicity. In view of our results and the ongoing exploitation of J. curcas for other purposes, this plant could become an affordable and effective component of an integrated approach to schistosomiasis control.
TL;DR: To examine the relationship between hepatitis B virus (HBV) infection and biomarkers of aflatoxin exposure in West African children, a large number of children diagnosed with HBV in the region have had prior exposure toflatoxin.
Abstract: OBJECTIVES To examine the relationship between hepatitis B virus (HBV) infection and biomarkers of aflatoxin exposure in West African children. METHODS Sera from 444 children aged 3-4 years who were selected to be representative of their communities were analysed for aflatoxin-albumin (AF-alb) adducts and markers of hepatitis B infection. RESULTS There was large interindividual variation in adduct levels (range: 2.2 to 459 pg AF-lysine eq./mg albumin). Adduct level was strongly correlated with season, with an approximately twofold higher mean level in the dry season than the wet. Geometric mean adduct levels in uninfected children, chronic carriers and acutely infected children were 31.6 (n = 404), 44.9 (n = 34) and 96.9 (n = 6) pg/mg, respectively. The relationship of AF-alb level to ethnicity, month of sampling and HBV status was examined in a multiple regression model. Month of obtaining the blood sample (P = 0.0001) and HBV status (P = 0.0023) each made a highly significant contribution to the model; the high AF-alb levels were particularly associated with acute infection. Elevated serum transaminase levels were significantly (P < 0.002) associated with HBV status, with acutely infected children having the highest levels. Ethnicity was not significantly associated with AF-alb adduct levels in the model (P = 0.09). CONCLUSIONS HBV infection and month of sampling both significantly influence AF-alb adduct levels. The effect of seasonality on adducts was also observed in a previous study of 347 Gambian adults, although there was no correlation between adduct level and HBV status in that population. This difference between children and adults may reflect a more severe effect of HBV infection, particularly acute infection, in childhood on hepatic AF metabolism.
TL;DR: Assessment of disabilities following pneumococcal and Hib meningitis in The Gambia found major handicaps found were hearing loss, mental retardation, motor abnormalities and seizures, which show that despite treatment with effective antibiotics, pneumococCal and HibMeningitis kill many Gambian children and leave many survivors with severe sequelae.
Abstract: In developing countries, endemic childhood meningitis is a severe disease caused most commonly by Streptococcus pneumoniae or Haemophilus influenzae type b (Hib). Although many studies have shown that fatality rates associated with meningitis caused by these organisms are high in developing countries, little is known about the long-term outcome of survivors. The purpose of this study was to assess the importance of disabilities following pneumococcal and Hib meningitis in The Gambia. 257 children aged 0-12 years hospitalized between 1990 and 1995 with culture-proven S. pneumoniae (n = 134) or Hib (n = 123) meningitis were included retrospectively in the study. 48% of children with pneumococcal meningitis and 27% of children with Hib meningitis died whilst in hospital. Of the 160 survivors, 89 (55%) were followed up between September 1996 and October 1997. Of the children with pneumococcal meningitis that were traced, 58% had clinical sequelae; half of them had major disabilities preventing normal adaptation to social life. 38% of survivors of Hib meningitis had clinical sequelae, a quarter of whom had major disabilities. Major handicaps found were hearing loss, mental retardation, motor abnormalities and seizures. These data show that despite treatment with effective antibiotics, pneumococcal and Hib meningitis kill many Gambian children and leave many survivors with severe sequelae. Hib vaccination is now given routinely in The Gambia; an effective pneumococcal vaccine is needed.
TL;DR: The methods used by other researchers for valuing indirect cost are compared, demonstrating the significant impact that methods of measurement and valuation can have on the estimation of indirect cost, and justifying the recommendation for methodological research in this area.
Abstract: Short-run economic consequences of 'malaria' on households were examined in a household survey in Matale, a malaria-endemic district of Sri Lanka. On average a household incurred a total cost of Rs 318 (US$ 7) per patient who fully recovered from 'malaria'. 24% of this was direct cost, 44% indirect cost for the patient and 32% indirect cost for the household. Direct costs were greater for those seeking treatment in the private sector. Notably a large proportion of direct costs was spent on complementary goods such as vitamins and foods considered to be nutritional. Indirect cost was measured and valued on the basis of output/ income losses incurred at the household level rather than using a general indicator such as average wage rate. Loss of output and wages accounted for the highest proportion of the indirect cost of the patients as well as the households. Relative to children, more young adults and middle-aged people had 'malaria' which also caused greater economic loss in these age groups. Women tended to care for patients rather than substitute their labour to cover productive work lost due to illness. We compare the methods used by other researchers for valuing indirect cost, demonstrating the significant impact that methods of measurement and valuation can have on the estimation of indirect cost, and justify the recommendation for methodological research in this area.
TL;DR: The Tamil Nadu programme showed that large‐scale repeated annual DEC mass treatment is feasible and that existing health services are capable of delivering the drug to all communities.
Abstract: This paper reports on DEC distribution and compliance with treatment in a large-scale annual single-dose mass treatment programme to eliminate lymphatic filariasis in the south Indian state of Tamil Nadu. 76.9% of households (82.5% in rural areas and 58.0% in urban areas) were aware of drug distribution for control of filariasis. DEC was given to 70% (= distribution rate) (range 0-92%) of the population and 53.5% (range 12-89%) complied with treatment. The distribution rate was more than 75% in 74% of the villages and compliance was in the range of 51-75% in 76% of the villages. About 5% of the treated population reported side-effects. Distribution and compliance were higher in rural than urban areas and similar between males and females. Qualitative data showed that some socio-economic factors, logistic and drug-related problems and people's poor knowledge and perceived benefits of treatment played a role in a proportion of the population not receiving or taking the drug. The Tamil Nadu programme showed that large-scale repeated annual DEC mass treatment is feasible and that existing health services are capable of delivering the drug to all communities. While even poor to moderate compliance rates can reduce the vector transmission of infection to some extent, improved drug distribution and compliance with treatment are necessary to consolidate the gains of earlier rounds of treatment and achieve the goal of filariasis elimination within a reasonable time frame.
TL;DR: The presence of clinical disease and the serological results for animals and humans and infected Hyalomma ticks provide ample evidence of the presence of CCHF virus in yet another country in the Arabian Peninsula.
Abstract: In 1995 and 1996, 4 persons from the Sultanate of Oman were confirmed with clinical Crimean-Congo haemorrhagic fever (CCHF). To assess the prevalence of CCHF virus infection in Oman, a convenience sample of imported and domestic animals from farms, abattoirs and livestock markets was examined by enzyme-linked immunosorbent assay (ELISA) for immunoglobulin G (IgG) antibodies to CCHF virus. Ticks were collected from selected animals, identified, pooled by species, host and location and tested for evidence of infection with CCHF virus by antigen-capture ELISA. Serum samples from individuals working in animal and nonanimal contact-related jobs were also tested for CCHF antibodies. Serological evidence of infection was noted in 108 (22%) of 489 animals. Most of the ticks collected (618 of 912) from all species of sampled livestock were Hyalomma anatolicum anatolicum, a competent vector and reservoir of CCHF virus. 243 tick pools were tested for CCHF antigen, and 19 pools were positive. Of the individuals working in animal contact-related jobs, 73 (30.3%) of 241 non-Omani citizens and only 1 (2.4%) of 41 Omani citizens were CCHF antibody-positive. Butchers were more likely to have CCHF antibody than persons in other job categories. The presence of clinical disease and the serological results for animals and humans and infected Hyalomma ticks provide ample evidence of the presence of CCHF virus in yet another country in the Arabian Peninsula.
TL;DR: Both gravidity and antimalarial drug use were independent predictors of sub microscopic P. falciparum infections and a raised proportion of submicroscopic parasitaemia among infected women grew.
Abstract: Malarial parasitaemia below the threshold of microscopy but detectable by polymerase chain reaction (PCR) assays is common in endemic regions. This study was conducted to examine prevalence, predictors, and effects of submicroscopic Plasmodium falciparum infections in pregnancy. In a cross-sectional study among 530 pregnant women in Ghana, plasmodial infections were assessed by microscopy and PCR assays. Concentrations of haemoglobin and C-reactive protein (CRP) were measured and antimalarial drugs (chloroquine, pyrimethamine) in urine were demonstrated by ELISA dipsticks. By microscopy, 32% of the women were found to harbour malaria parasites. This rate increased to 63% adding the results of the parasite-specific PCR. P. falciparum was present in all but one infection. With increasing gravidity, infection rates and parasite densities decreased and the proportions of submicroscopic parasitaemia among infected women grew. Correspondingly, anaemia, fever and evidence of inflammation (CRP > 0.6 mg/dl) were more frequent in primigravidae than in multigravidae. Antimalarial drugs were detected in 65% of the women and were associated with a reduced prevalence of P. falciparum infections and a raised proportion of submicroscopic parasitaemia. Both gravidity and antimalarial drug use were independent predictors of submicroscopic P. falciparum infections. These infections caused a slight reduction of Hb levels and considerably increased serum concentrations of CRP. Conventional microscopy underestimates the actual extent of malarial infections in pregnancy in endemic regions. Submicroscopic P. falciparum infections are frequent and may contribute to mild anaemia and inflammation in seemingly aparasitaemic pregnant women.
TL;DR: Endobacteria of the genus Wolbachia in filarial nematodes are related to Rickettsiaceae and can be depleted by tetracycline antibiotics, which blocks female worm development as well as early embryogenesis, in contrast to the currently used microfilaricidal ivermectin.
Abstract: Endobacteria of the genus Wolbachia in filarial nematodes are related to Rickettsiaceae and can be depleted by tetracycline antibiotics. This depletion blocks female worm development as well as early embryogenesis, in contrast to the currently used microfilaricidal ivermectin which blocks only the last stage of embryogenesis. Since targeting Wolbachia is becoming an area of research for the treatment of human filariases, it was investigated if antibiotics other than tetracyclines are able to deplete Wolbachia from filariae. BALB/c mice infected with the rodent filaria Litomosoides sigmodontis were treated with erythromycin, chloramphenicol or ciprofloxacin. All drugs were well resorbed and resulted in serum levels clearly above breakpoint levels for bacteria susceptible to the respective antibiotic. However, contrary to tetracycline, none of these antibiotics depleted Wolbachia or altered worm development and fertility, as evidenced by immunohistology, immunoelectron microscopy and semiquantitative PCR.
TL;DR: The results indicate that modern medical care plays a major role in the treatment of infectious illness among children in rural Guatemala, with visits to pharmacists, doctors and the staff at government health facilities occurring much more frequently than visits to curers and other traditional practitioners.
Abstract: Relying on data from the 1995 Guatemalan Survey of Family Health (EGSF), we analyse the relationship between child illness and health-seeking behaviour. Information on illness was collected for 3193 children. This analysis is based on 870 of these who became ill with diarrhoeal or respiratory disease during a 13-day period prior to interview. Estimates are derived from logistic models of the probability of seeing any or a specific type of health care provider as a function of characteristics of the illness on a given day and the child. The results indicate that modern medical care plays a major role in the treatment of infectious illness among children in rural Guatemala, with visits to pharmacists, doctors and the staff at government health facilities occurring much more frequently than visits to curers and other traditional practitioners. In general, families are much more likely to seek out a health care provider when a child experiences fever and gastrointestinal symptoms than when suffering from respiratory and other symptoms, and when a mother perceives the illness to be serious. The results also indicate that infants, low parity children, and children assessed as having generally been in good health are more likely to visit health care providers than other children. However, the particular associations often vary by type of health care provider.
TL;DR: Heterogeneity of HIV prevalence among pregnant women in Hlabisa health district, South Africa and to correlate this with proximity of homestead to roads is described.
Abstract: OBJECTIVE To describe heterogeneity of HIV prevalence among pregnant women in Hlabisa health district, South Africa and to correlate this with proximity of homestead to roads. METHODS HIV prevalence measured through anonymous surveillance among pregnant women and stratified by local village clinic. Polygons were created around each clinic, assuming women attend the clinic nearest their home. A geographical information system (GIS) calculated the mean distance from homesteads in each clinic catchment to nearest primary (1 degrees) and to nearest primary or secondary (2 degrees) road. RESULTS We found marked HIV heterogeneity by clinic catchment (range 19-31% (P < 0.001). A polygon plot demonstrated lower HIV prevalence in catchments remote from 1 degrees roads. Mean distance from homesteads to nearest 1 degrees or 2 degrees road varied by clinic catchment from 1623 to 7569 m. The mean distance from homesteads to a 1 degrees or 2 degrees road for each clinic catchment was strongly correlated with HIV prevalence (r = 0.66; P = 0.002). CONCLUSIONS The substantial HIV heterogeneity in this district is closely correlated with proximity to a 1 degrees or 2 degrees road. GIS is a powerful tool to demonstrate and to start to analyse this observation. Further research is needed to better understand this relationship both at ecological and individual levels, and to develop interventions to reduce the spread of HIV infection.
TL;DR: A two‐pronged approach is proposed by starting quality improvement of maternity care from both ends of maternity services: preventive interventions for all women and hospital‐based obstetric care.
Abstract: This study assesses the performance of maternity care and its specific service components (preventive interventions in antenatal care, antenatal screening, referral, obstetric care) in Banke District, Nepal, using a set of structure, process, and output/outcome indicators. Data sources included health service documents in 14 first level health units and two hospitals, covering 1378 pregnancies and 1323 deliveries, structured observations, antenatal exit interviews (n = 136) and interviews with maternity users (n = 146). Coverage of antenatal care (28%) and skilled delivery care (16%) was low. In antenatal care, preventive interventions were only partially implemented (effective iron supplementation in 17% of users). On average one minute was spent on individual counselling per consultation. 41% of pregnancies were identified as high risk and 15% received referral advice, which was followed in only 32%. Hospital deliveries accounted for 9.8% of all deliveries. Hospital-based maternal mortality was 6.8/1000 births and the stillbirth rate 70/1000. High rates of stillbirth were observed in breech delivery (258/1000 births), caesarean section (143/1000) and twin delivery (133/1000). The risk of stillbirth was higher for rural women (RR 2.3; 95% CI 1.51-3.50) and appeared to be related to low socio-economic status. Emergency admissions were rare and accounted for 3.4% of hospital deliveries or only 0.4% of all expected deliveries. There was hardly any accumulation of high-risk pregnancies at hospital. The population-based rate of caesarean section was 1.1% (urban 2.3%, rural 0.2%). The estimated unmet obstetric need was high (82 cases or 61% of expected live-threatening maternal conditions did not receive appropriate intervention). The limited effectiveness of maternity care is the result of deficiencies of all service components. We propose a two-pronged approach by starting quality improvement of maternity care from both ends of maternity services: preventive interventions for all women and hospital-based obstetric care. Antenatal screening needs to be rationalized by reducing inflated risk catalogues that result in stereotypical and often rejected referral advice.
TL;DR: The results of this survey call for prompt educational action for the correct treatment of uncomplicated malaria/soumaya, particularly for mothers and possibly for shopkeepers, as malaria is a common disease in this area and improved case‐management at home could only be beneficial.
Abstract: We studied child malaria treatment practices among mothers living in the District of Yanfolila in southern Mali. For sampling, we first chose five of 13 health areas with probability proportional to size. Then villages, compounds and mothers with at least one child aged 1-5 years were randomly chosen. We assessed the spleen size of one 1-5 year-old child of each mother, collected a thick blood film and recorded the body temperature of every child whose mother thought he/she was sick. 399 mothers in 28 villages were interviewed with a structured questionnaire divided into two parts. If the child had had soumaya (a term previously associated with uncomplicated malaria) during the past rainy season, we asked about signs and symptoms, health-seeking behaviour (who the mother consulted first) and treatment. If not, information about knowledge of the disease and treatment to be given was collected. 86% of the mothers interviewed stated that their child had been sick and almost half of them had had soumaya. All mothers named at least one sign by which they recognized the disease. Vomiting, fever and dark urine/yellow eyes/jaundice were the three most common signs mentioned. 75.8% managed their child's disease at home and used both traditional and modern treatment. The most common anti-malarial drug was chloroquine, often given at inappropriate dosage. The sensitivity and specificity of the mothers' diagnosis was poor, although this might be explained by the large percentage of children who had already been treated at the time of the interview. The results of our survey call for prompt educational action for the correct treatment of uncomplicated malaria/soumaya, particularly for mothers and possibly for shopkeepers. The high spleen rate (58.1%) among randomly selected children confirms that malaria is a common disease in this area. Improved case-management at home could only be beneficial.
TL;DR: The data indicate that there has been a marked improvement in infant and under‐five mortality in both sets of villages, with significantly lower mortality rates for the 1–4‐year‐olds when the PHC programme was well supported in the 1980s and when support for PHC was reduced after 1994.
Abstract: Using data from a longitudinal study conducted in 40 villages by the UK Medical Research Council in the North Bank Division of The Gambia beginning in late 1981 the authors examined infant and child mortality over a 15-year period for a population of about 17000 people. Comparisons are drawn between villages with and without primary health care (PHC). The extra facilities in the PHC villages include a paid community health nurse (for about every 5 villages) a village health worker and a trained traditional birth attendant. Maternal and child health services with a vaccination program are accessible to residents in both PHC and non-PHC villages. The data indicate that there has been a marked improvement in infant and under-five mortality in both sets of villages. Following the establishment of the PHC system in 1983 infant mortality dropped from 134/1000 in 1982-83 to 69/1000 in 1992-94 in the PHC villages and from 155/1000 to 91/1000 in the non-PHC villages over the same period. During 1982-83 and 1992-94 the death rates for children aged 1-4 fell from 42/1000 to 28/1000 in the PHC villages and from 45/1000 to 38/1000 in the non-PHC villages. Since 1994 when supervision of the PHC system weakened infant mortality rates in the PHC villages have risen to 89/1000 in 1994-96. The rates in the non-PHC villages fell to 78/1000 for this period. The under-five mortality rates in both sets of villages have converged to 34/1000 for 1994-96. When the PHC program was well supported in the 1980s the authors saw significantly lower mortality rates for the 1-4 year olds. These differences disappeared when support for PHC was reduced after 1994. The differential effects on infant mortality are less clear-cut. (authors modified)
TL;DR: High parasite density sometimes associated with fever can no longer be considered as the gold standard in the diagnosis of malaria, and other approaches, such as decision‐making processes involving clinical, biological and ecological variables must be developed, especially in highly endemic areas where Plasmodium infection is the rule rather than the exception.
Abstract: Temporal variations of blood parasite density were evaluated in a longitudinal study of young, asymptomatic men in a village with endemic malaria in Mali (West Africa). Our main intention was to challenge the value of a single measure of parasite density for the diagnosis of malaria, and to define the level of endemicity in any given area. Parasitaemia and body temperature were recorded three times a day in the wet season (in 39 subjects on 12 days) and in the dry season (in 41 subjects on 13 days). Two thousand nine hundred and fifty seven blood smears (98.5% of the expected number) were examined for malaria parasites. We often found 100-fold or greater variations in parasite density within a 6-hour period during individual follow-up. All infected subjects had frequent negative smears. Although fever was most likely to occur in subjects with a maximum parasite density exceeding 10000 parasites/mm3 (P = 0.009), there was no clear relationship between the timing of these two events. Examples of individual profiles for parasite density and fever are presented. These variations (probably due to a 'sequestration-release' mechanism, which remains to be elucidated) lead us to expect a substantial impact on measurements of endemicity when only a single sample is taken. In this study, the percentage of infected individuals varied between 28.9% and 57.9% during the dry season and between 27.5% and 70.7% during the wet season. The highest rates were observed at midday, and there were significant differences between days. Thus, high parasite density sometimes associated with fever can no longer be considered as the gold standard in the diagnosis of malaria. Other approaches, such as decision-making processes involving clinical, biological and ecological variables must be developed, especially in highly endemic areas where Plasmodium infection is the rule rather than the exception and the possible causes of fever are numerous.
TL;DR: The stability of seropositivity and the pattern of results obtained with both immunological and parasitological examinations support the view that individual factors, such as immune response to infection, might be involved in the isolated CATT positivity phenomenon.
Abstract: Summary The aetiological diagnosis of human African trypanosomiasis (HAT) is based on the detection of the parasite, but currently available parasitological test5 have low sensitivity and are hampered by fluctuating parasitaemia. The identification of seropositive individuals on whom to focus parasitologicql examination is based on antibody detection by means of the Card Agglutination Trypanosomiasis Test (CATT/T.b.gambiexy). A complicating phenomenon is the occurrence of-serologically positive but parasitologically unconfirmed results (isolated CATT positivity). This work presents a two-year longitudinal serological, parasitological and molecular follow-up of CATT-positive individuals including repeated examinations of e+& individual, t~ study the evolution over time of seropositivity at both the population and the individual leGls. At the population level, the rate of seropositivity decreased during the first months of the survey, and afterwards showed remarkable stability Ar the individual level, the results reveal &e extreme heterogeneity of this population, with subjects showing fluctuating results, others with a short transient CATT positivity, and subje‘cts that maintain their seropositivity over time. The stability of seropositivity and the pattern of results obtained with both immunological and parasitological examinations support che view that individual factors, such as immune response to infection, might be involved in che isolated CATT positivity phenomenon.
TL;DR: The validity of the algorithms when they were applied to VA data from two secondary sites in Ghana and Tanzania is reported here on the degree to which the algorithms replicated the physician‐generated CSMF for major causes of death, when applied to the same VA data.
Abstract: Summary background Verbal autopsy (VA) is used to ascertain causes of death using information obtained from bereaved relatives. Causes of death can be ascertained from VA questionnaires by a panel of physicians or from predefined algorithms. In a previous study, we developed data-derived algorithms using VA data from 796 adult deaths in hospitals in Tanzania, Ethiopia, and Ghana (primary sites). These computerized algorithms accurately estimated the cause-specific mortality fractions (CSMFs) for deaths due to injuries, meningitis, TB/AIDS and diarrhoeal diseases in the primary sites. Since the same data were used to generate and to validate the algorithms, the accuracy of our algorithms may have been overestimated. We report here on the validity of the algorithms when they were applied to VA data from two secondary sites in Ghana and Tanzania. Here, ‘validity’ is taken to mean the degree to which the algorithms replicated the physician-generated CSMF for major causes of death, when applied to the same VA data.
methods VA interviews were conducted in two secondary sites: in Navrongo, Ghana, on 406 adult deaths, where three local physicians independently reviewed the questionnaires and assigned a cause of death. In Morogoro, Tanzania, VA interviews were conducted on 209 adult deaths, and a panel of physicians independently reviewed the VA questionnaires together with the hospital death certificates or hospital records to determine the cause of death. The CSMF obtained using each algorithm was compared with the CSMF obtained using physician review.
results For injuries and meningitis, the algorithms and physician review estimated a similar CSMF in the Morogoro and Navrongo data. For TB/AIDS, the algorithm estimated a similar CSMF as the physicians in Morogoro. The algorithm for diarrhoeal diseases did not agree closely with the physicians in Morogoro or Navrongo.
conclusions In general, our data-derived algorithms for assigning causes of death due to injuries, meningitis, and TB/AIDS estimated a similar CSMF as the physicians in the secondary sites. Recommendations for further validation and refinement are discussed. Computerized algorithms offer a potentially quick, affordable, and feasible method for assigning causes of death in mortality surveillance or studies using VA.
TL;DR: To compare the outcome of treatment of Sudanese kala‐azar patients treated under field conditions with either branded sodium stibogluconate (SSG) (Pentostam GlaxoWellcome) or generic SSG (Albert David Ltd, Calcutta, supplied by International Dispensary Association, Amsterdam).
Abstract: OBJECTIVE To compare the outcome of treatment of Sudanese kala-azar patients treated under field conditions with either branded sodium stibogluconate (SSG) (Pentostam GlaxoWellcome) or generic SSG (Albert David Ltd, Calcutta, supplied by International Dispensary Association, Amsterdam). METHOD Randomised comparison. 271 patients were treated with Pentostam and 245 with generic SSG. RESULTS No statistically significant differences in cure rate or mortality were detected between Pentostam and generic SSG. No differences in side-effects between the two drugs were noted. The initial cure rate at the time of discharge was 93.7 and 97.6%, respectively; the death rate during treatment 5.9 and 2.4%. Six months follow up was achieved in 88.5% of the discharged patients. Two patients had died in the Pentostam group and two had died in the generic SSG group, giving a final death rate of 7.5 and 3.7%. The number of relapses in the Pentostam and generic SSG groups were 3 and 1, respectively. The final cure rates, calculated at 6 months after discharge, were 91.3% and 95.9%. CONCLUSION No difference was observed in the performance of generic SSG compared to Pentostam for the treatment of visceral leishmaniasis in Sudan. Generic SSG can be routinely and safely used for the treatment of kala-azar. Generic SSG costs only 1/14 of the price of Pentostam. The use of generic SSG may make treatment of kala-azar affordable for national governments in Africa.
TL;DR: A randomised community trial was conducted to investigate the effect of providing surgery in villages on surgical uptake in The Gambia and found no change in the number of patients receiving surgery.
Abstract: Surgery for trachomatous trichiasis prevents blindness and is advocated by the WHO as part of the Surgery Antibiotic therapy Facial cleanliness and Environmental improvement (SAFE) strategy for the global elimination of trachoma. The authors conducted a randomized community trial to investigate the effect of providing surgery in villages on surgical uptake in The Gambia. 56 villages from two divisions were assigned to eight pairs of clusters matched by geographical division and proximity. One cluster from each pair was randomly assigned to receive village-based surgery and the other cluster health center-based surgery. Outcome measures were uptake rates and surgical results after 1 week and 3 months. The paired t-test was used to analyze the results. Overall uptake was 66% in the village-based clusters and 44% in the health-center-based clusters. Subjects in the village-based surgery arm had significantly shorter journey times (P = 0.01) and lower costs (P = 0.002). The mean difference in absolute acceptance rates of surgery was 20% better in village-based clusters (95% confidence interval [CI] –9% to +49%; P = 0.15) which would equate to an improvement of 45% (95% CI -20% to 120%) on the average acceptance rates of 44% in the health center-based group. These results strongly suggest better surgical uptake when surgery is provided in patients villages due to lower cost to the patient time saved and less fear of operation. (authors)