Survey of Community Knowledge, Attitudes, and Practices During a Malaria Epidemic in Central Java, Indonesia

We surveyed adults in a randomly selected sample of 1,000 households in 50 villages in nine malarial sub-districts in Purworejo, central Java, Indonesia from May to July 2001. The survey assessed malaria knowledge, attitudes, and practices in communities experiencing epidemic malaria to begin exploring broad strategies for controlling the disease in the region. A pre-tested survey instrument consisting of 93 questions addressed demographic characteristics, socioeconomic factors, knowledge and perceptions of malaria, burden and severity of disease, treatment-seeking behavior, malaria prevention practices, and perceptions of government malaria control efforts. The survey was taken by in-person interview of all subjects. Most (97%) subjects were aware of malaria and more than two-thirds correctly identified mosquitoes as the vector. Forty-one percent of households in both forest/hilly and agricultural/urban areas reported malaria illness in the past year. Thirty-six percent (357 households) owned at least one bed net, 92% of these had been purchased by the owners. However, only 36% of households with bed nets affirmed their use as a means of preventing malaria. Nearly all respondents reported a willingness to accept spraying of residual insecticides for malaria prevention, yet less than 5% were willing to pay a nominal fee (US $3) for this service. Fifty-two percent of respondents reported self-treatment of malaria illness without visiting a health facility. This assessment of knowledge, attitudes, and practices showed a broad awareness of malaria and its consequences among residents of malarial areas in the Menoreh Hills of Central Java

Production and validation of durable, high quality standardized malaria microscopy slides for teaching, testing and quality assurance during an era of declining diagnostic proficiency

Background: Sets of Giemsa-stained, blood smear slides with systematically verified composite diagnoses would contribute substantially to development of externally validated quality assurance systems for the microscopic diagnosis of malaria. Methods: whole blood from Plasmodium-positive donors in Cambodia and Indonesia and individuals with no history of risk for malaria was collected. Using standard operating procedures, technicians prepared Giemsastained thick and thin smears from each donor. One slide from each of the first 35 donations was distributed to each of 28 individuals acknowledged by reputation as having expertise in the microscopic diagnosis of malaria. These reference readers recorded presence or absence of Plasmodium species and parasite density. A composite diagnosis for each donation was determined based on microscopic findings and species-specific small subunit ribosomal RNA (ssrRNA) DNA polymerase chain reaction (PCR) amplification. Results: More than 12, 000 slides were generated from 124 donations. Reference readers correctly identified presence of parasites on 85% of slides with densities \u3c100 parasites/μl, which improved to 100% for densities \u3e350 parasites/μl. Percentages of agreement with composite diagnoses were highest for Plasmodium falciparum (99%), followed by Plasmodium vivax (86%). Conclusion: Herein, a standardized method for producing large numbers of consistently high quality, durable Giemsa-stained blood smears and validating composite diagnoses for the purpose of creating a malaria slide repository in support of initiatives to improve training and competency assessment amidst a background of variability in diagnosis is described

Reader technique as a source of variability in determining malaria parasite density by microscopy

BACKGROUND: Accurate identification and quantification of malaria parasites are critical for measuring clinical trial outcomes. Positive and negative diagnosis is usually sufficient for the assessment of therapeutic outcome, but vaccine or prophylactic drug trials require measuring density of infection as a primary endpoint. Microscopy is the most established and widely-used technique for quantifying parasite densities in the blood. METHODS: Results obtained by 24–27 expert malaria microscopists, who had independently read 895 slides from 35 donors, were analysed to understand how reader technique contributes to discrepancy in measurements of parasite density over a wide range of densities. RESULTS: Among these 35 donations, standard deviations ranged from 30% to 250% of the mean parasite density and the percent discrepancy was inversely correlated with the mean parasite density. The number of white blood cells indexed and whether parasites were counted in the thick film or thin film were shown to significantly contribute to discrepancy amongst microscopists. CONCLUSION: Errors in microscopy measurements are not widely appreciated or addressed but have serious consequences for efficacy trials, including possibly abandoning promising vaccine candidates

Epidemiological Measures of Risk of Malaria

Estimates of the risk of infection by the parasites that cause malaria govern decisions regarding vector control, chemoprophylaxis, therapeutic management, and clinical classifications of immunological susceptibility to infection. Gauging the risk of malaria represents a critical step in its management and the investigation of its consequences. The term malariometry is applied to the numerical measure of risk of malaria in communities (9). Many approaches have been developed and applied to malariometry, but no single method stands out as universally applicable. Instead, individual measures of risk must be suitable for specific questions posed in the context of what may be practically measured. For example, passive surveillance provides a superior measure of risk where the infrastructure of diagnosis and reporting is well developed and the risk of infection relatively low, e.g., in the United States, where conducting active cross-sectional surveys would yield little useful information at great cost. Active surveillance for cases is suited to areas with relatively high risk, unreliable diagnostic capabilities and inadequate reporting infrastructure. This chapter strives to catalog measures of risk of malaria and define their utility in the context of local parameters of endemicity, infrastructure, and intent of inquiry

Epidemic Malaria in the Menoreh Hills of Central Java

After more than 50 years of effective management, resurgent malaria threatens residents in the Menoreh Hills and the foothills of the Dieng Plateau of Central Java, Indonesia. The Dieng Plateau dominates the highland center of Central Java. The steep Menoreh Hills, surrounded by rice paddy habitats, cover approximately 500 km2 with no peaks greater than 1,000 m. We studied epidemic malaria in Purworejo district, one of the three districts containing the Menoreh Hills. Between 1986 and 1995, the annual parasite incidence (API) in Purworejo ranged from 2 to 11 cases per 1,000 residents per year and was typically approximately 5 per 1,000. In 2000 the API was 44.5. This sharp increase was confined to subdistricts in and around the Menoreh Hills and Dieng Plateau foothills. The primary vectors of malaria, those favoring steep, forested hillsides on Java, were Anopheles maculatus and Anopheles balabacensis. Deterioration of vector control activity, followed by a severe economic downturn in 1997, may explain the epidemic. Malaria in the Menoreh Hills and lower Dieng Plateau threatens surrounding areas of rice paddy inhabited by Anopheles aconitus as well as a nearby coastal habitat where the even more efficient vector Anopheles sundaicus occurs in abundance. Most of the 130 million people living on Java never experienced the hyper- and holoendemic malaria that occurred throughout most of the island before the effective DDT spraying and chloroquine treatment campaigns of the 1950s. Reintroduced endemic malaria threatens the island of Java

Short Report: Hepatitis B Infection and Severe \u3ci\u3ePlasmodium Falciparum\u3c/i\u3e Malaria in Vietnamese Adults

We investigated the prevalence of infection with hepatitis B virus among adult Vietnamese patients hospitalized for severe Plasmodium falciparum malaria. Sera from patients admitted with severe malaria in Ho Chi Minh City, Vietnam, between May 1991 and January 1996 were assayed for hepatitis B surface antigen (HBsAg) by a commercial enzyme-linked immunosorbent assay kit. The overall prevalence of HBsAg was 23.77% (77 of 324). This was higher than reported estimates of prevalence in the general catchment population for the study hospital (mean, 9.8%; range, 9–16%). No association was found between risk of death caused by severe malaria and HBsAg. Patients admitted with cerebral malaria had a slightly greater risk of registering positive for HBsAg (relative risk, 1.28; 95% confidence interval, 1.04–1.58) relative to other manifestations of severe malaria. Chronic infection with hepatitis B virus may be a risk factor for severe malaria

Demographic Risk Factors for Severe and Fatal Vivax and Falciparum Malaria Among Hospital Admissions in Northeastern Indonesian Papua

Between January 1998 and December 2000, the Jayapura Provincial Public Hospital in northeastern Indonesian New Guinea (Papua) admitted 5,936 patients with a diagnosis of malaria. The microscopic diagnosis at admission was Plasmodium falciparum (3,976, 67%), Plasmodium vivax (1,135, 19%), Plasmodium malariae (8, \u3c 1%), and mixed species infections (817, 14%). Approximately 9% (367) of patients were classified as having severe malaria (277 P. falciparum, 36 P. vivax, 53 mixed infections, and 1 P. malariae) and 88 died (79 P. falciparum/mixed infections and 9 P. vivax). Risk of fatal outcomes among severe malaria patients was indistinguishable between those with falciparum versus vivax malaria (OR=0.89; P=0.771). Compared with non-pregnant women, pregnant women showed no higher risk of severe malaria (P=0.643) or death caused by severe malaria (P=0.748). This study compares admissions per population (based on census data), parasitemia, morbidity, and mortality among children versus adults, pregnant versus non-pregnant women, and urban/suburban versus rural residents

Seasonal Malaria Attack Rates in Infants and Young Children in Northern Ghana

The incidence density of infection and disease caused by Plasmodium falciparum in children aged six to 24 months living in the holoendemic Sahel of northern Ghana was measured during the wet and dry seasons of 1996 and 1997. At the beginning of each season, a cohort composed of 259 and 277 randomly selected children received supervised curative therapy with quinine and Fansidar® and primaquine for those with normal glucose-6-phosphate dehydrogenase activity. The 20 weeks of post-therapy follow-up consisted of three home visits weekly and examination of Giemsastained blood films once every two weeks. Blood films were also taken from children brought to clinic with illness. The incidence density of parasitemia after radical cure was 4.7 infections/person-year during the dry season and 7.1 during the wet season (relative risk 1.51, 95% confidence interval [CI] 1.25–1.81; P = 0.00001). Although the mean parasitemia count at time of reinfection in the dry season (3,310/µ) roughly equaled that in the wet season (3,056/µ; P = 0.737), the risk ratio for parasitemia \u3e 20,000/µ during the wet season was 1.71 (95% CI 1.2–2.4; P = 0.0025). The risk ratio for parasitemia \u3e 20,000/l with fever during the wet season was 2.45 (95% CI 1.5–4.1; P = 0.0002). The risk ratio for anemia (hemoglobin \u3c 8 g/dl) at first post-radical cure parasitemia showed no difference between seasons (1.0; 95 % CI 0.73–1.4; P = 0.9915). We did not see seasonal differences in anemia known to exist in this region, probably because the longitudinal cohort design using first parasitemia as an end point prevented the subjects from developing the repeated or chronic infections required for anemia induction. These findings bear upon the design of malaria drug and vaccine trials in holoendemic areas

Production and validation of durable, high quality standardized malaria microscopy slides for teaching, testing and quality assurance during an era of declining diagnostic proficiency

Background: Sets of Giemsa-stained, blood smear slides with systematically verified composite diagnoses would contribute substantially to development of externally validated quality assurance systems for the microscopic diagnosis of malaria. Methods: whole blood from Plasmodium-positive donors in Cambodia and Indonesia and individuals with no history of risk for malaria was collected. Using standard operating procedures, technicians prepared Giemsastained thick and thin smears from each donor. One slide from each of the first 35 donations was distributed to each of 28 individuals acknowledged by reputation as having expertise in the microscopic diagnosis of malaria. These reference readers recorded presence or absence of Plasmodium species and parasite density. A composite diagnosis for each donation was determined based on microscopic findings and species-specific small subunit ribosomal RNA (ssrRNA) DNA polymerase chain reaction (PCR) amplification. Results: More than 12, 000 slides were generated from 124 donations. Reference readers correctly identified presence of parasites on 85% of slides with densities \u3c100 parasites/μl, which improved to 100% for densities \u3e350 parasites/μl. Percentages of agreement with composite diagnoses were highest for Plasmodium falciparum (99%), followed by Plasmodium vivax (86%). Conclusion: Herein, a standardized method for producing large numbers of consistently high quality, durable Giemsa-stained blood smears and validating composite diagnoses for the purpose of creating a malaria slide repository in support of initiatives to improve training and competency assessment amidst a background of variability in diagnosis is described

Atovaquone/Proguanil Therapy for \u3ci\u3ePlasmodium falciparum\u3c/i\u3e and \u3ci\u3ePlasmodium vivax\u3c/i\u3e Malaria in Indonesians Who Lack Clinical Immunity

Thirty-eight of 295 subjects participating in a randomized, double-blind, placebo-controlled trial of the efficacy of daily administration of atovaquone/proguanil for malaria prevention developed malaria at some time during the 20-week prophylaxis period. These subjects (3 atovaquone/proguanil recipients and 35 placebo recipients) were treated with 4 tablets of atovaquone/proguanil per day for 3 days. Atovaquone/proguanil provided safe, well-tolerated, and effective therapy for uncomplicated malaria in nonimmune Indonesians