Probable autochthonous Plasmodium vivax malaria transmission in Michigan: case report and epidemiological investigation.

In September 1995, a Michigan resident with no history of international travel was diagnosed with Plasmodium vivax infection, and local mosquito-borne transmission was suspected. An epidemiological investigation did not identify additional cases of local transmission, and there was no apparent link to the 12 imported malaria cases detected in the region. Potential sites of nighttime outdoor exposure included a campground in a swampy area, close to a racetrack frequented by international travelers, some of whom were known to come from countries with malaria transmission. Entomological investigation identified Anopheles spp. larvae and adults near the campsite. Summer temperatures 4.2 degrees C above average would have contributed to shortened maturation time of P. vivax within the insect vector, increasing the likelihood of infectivity. These investigations indicated that this patient probably acquired P. vivax infection through the bite of a locally infected Anopheles spp. mosquito. Physicians need to consider malaria as a possible cause of unexplained febrile illness, even in the absence of international travel, particularly during the summer months.

Evaluation of malaria surveillance using retrospective, laboratory-based active case detection in four southwestern states, 1995.

The global resurgence of malaria has raised concerns of the possible reintroduction of indigenous transmission in the United States. The Centers for Disease Control and Prevention's National Malaria Surveillance System, using data supplied by state and local health departments (SLHDs), is maintained to detect local malaria transmission and monitor trends in imported cases. To determine the completeness of reporting of malaria cases to SLHDs, cases identified by local surveillance systems were compared with those identified through active case detection conducted at all laboratories that receive clinical specimens from 11 metropolitan areas in Arizona, California, New Mexico, and Texas. Of the 61 malaria cases identified through either local surveillance or active case detection, 43 (70%) were identified by SLHDs (range by metropolitan area = 50-100%) and 56 (92%) through active case detection. High percentages of cases were identified by SLHDs in New Mexico (80%) and San Diego County (88%), where laboratories are required to send positive blood smears to the SLHD laboratory for confirmation. Completeness of reporting, calculated using the Lincoln-Peterson Capture-Recapture technique, was 69% for SLHD surveillance systems and 89% for laboratory-based active case detection. The high percentage of cases identified by the 11 SLHDs suggests that the National Malaria Surveillance System provides trends that accurately reflect the epidemiology of malaria in the United States. Case identification may be improved by promoting confirmatory testing in SLHD laboratories and incorporating laboratory-based reporting into local surveillance systems.

Malaria surveillance -- United States, 1994.

PROBLEM/CONDITION: Malaria is caused by infection with one of four species of Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, and P. malariae ), which are transmitted by the bite of an infective female Anopheles sp. mosquito. Most malarial infections in the United States occur in persons who have traveled to areas (i.e., other countries) in which disease transmission is ongoing. However, cases are transmitted occasionally through exposure to infected blood products, by congenital transmission, or by local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to adapt prevention recommendations. REPORTING PERIOD COVERED: Cases with onset of symptoms during 1994. DESCRIPTION OF SYSTEM: Malaria cases confirmed by blood smear are reported to local and/or state health departments by health-care providers and/or laboratories. Case investigations are conducted by local and/or state health departments, and the reports are transmitted to CDC through the National Malaria Surveillance System (NMSS), which was the source of data for this report. Numbers of cases reported through NMSS may differ from those reported through other passive surveillance systems because of differences in the collection and transmission of data. RESULTS: CDC received reports of 1,014 cases of malaria with onset of symptoms during 1994 among persons in the United States or one of its territories. This number represented a 20% decrease from the 1,275 cases reported for 1993. P. vivax, P. falciparum, P. malariae, and P. ovale accounted for 44%, 44%, 4%, and 3% of cases, respectively. More than one species was present in five persons (<1% of the total number of patients). The infecting species was not determined in 50 (5%) cases. The number of reported malaria cases in U.S. military personnel decreased by 86% (i.e., from 278 cases in 1993 to 38 cases in 1994). Of the U.S. civilians who acquired malaria during travel to foreign countries, 18% had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Five persons became infected while in the United States; the infection was transmitted to two of these persons through transfusion of infected blood products. The remaining three cases, which occurred in Houston, Texas, were probably locally acquired mosquitoborne infections. Four deaths were attributed to malaria. INTERPRETATION: The 20% decrease in the number of malaria cases from 1993 to 1994 resulted primarily from an 86% decrease in cases among U.S. military personnel after withdrawal from Somalia. Because most malaria cases acquired in Somalia during 1993 resulted from infection with P. vivax, there was a proportionately greater decrease during 1994 in the number of cases caused by P. vivax relative to those caused by P. falciparum. ACTIONS TAKEN: Additional information was obtained concerning the four fatal cases and the five cases acquired in the United States. Malaria prevention guidelines were updated and distributed to health-care providers. Persons traveling to a geographic area in which malaria is endemic should take the recommended chemoprophylactic regimen and should use protective measures to prevent mosquito bites. Persons who have a fever or influenza-like illness after returning from a malarious area should seek medical care; medical evaluation should include a blood smear examination for malaria. Malarial infections can be fatal if not promptly diagnosed and treated. Recommendations concerning prevention and treatment of malaria can be obtained from CDC.

Longitudinal evaluation of severely anemic children in Kenya: the effect of transfusion on mortality and hematologic recovery.

OBJECTIVE: To determine the effect of transfusion on hematologic recovery and mortality among severely anemic children during and after hospitalization in rural Kenya. DESIGN: Prospective cohort. METHODS: We collected clinical and laboratory information on all severely anemic children (hemoglobin < 5.0 g/dl) and a 33% sample of children with hemoglobin < or = 5.0 g/dl who were admitted to the pediatric ward of a rural Kenyan hospital during a 6 month study period. Children were followed during hospitalization and at 4 and 8 weeks after admission. RESULTS: Overall, 303 (25%) of the 1223 hospitalized children had hemoglobin < 5.0 g/dl, 30% of whom died during the study period. Severely anemic children who were transfused had a higher mean hemoglobin level at discharge (9.0 g/dl) than non-transfused children (5.8 g/dl, P < 0.001) and maintained a higher mean hemoglobin during the 8-week follow-up period. However, the presence of malaria parasitemia on follow-up negated the benefit of transfusion on hematologic recovery at both 4- and 8-week visits (longitudinal linear model, least square means, P > 0.05). Transfusion was associated with improved survival among children with respiratory distress who received transfusions within the first 2 days of hospitalization. CONCLUSIONS: The use of transfusion can be improved by targeting use of blood to severely anemic children with cardiorespiratory compromise, improving immediate availability of blood, and treating severely anemic children with effective antimalarial therapy.

PIP: The effect of blood transfusion on hematologic recovery and mortality both during and after hospitalization was investigated in a survey of children admitted to Siaya District Hospital (Kenya) in a 6-month period in 1991 with hemoglobin under 5.0 g/dl (n = 303) or 5.0 g/dl and above (n = 303). Children with hemoglobin under 5.0 g/dl (severe anemia) were younger and more likely to have malaria parasitemia and respiratory compromise than controls. 88 severely anemic children (30%) died during the study period. Severely anemic children who were transfused had a higher mean hemoglobin level at discharge (9.0 g/dl) than nontransfused children (5.8 g/dl) and maintained a higher mean hemoglobin in the 8-week post-discharge follow-up period. 15% of transfused and 17% of nontransfused children died after hospital discharge. Transfusion was associated with significantly improved survival among children with respiratory distress who were transfused within 2 days of hospital admission. However, the presence of malaria or parasitemia at follow-up negated the benefit of transfusion on hematologic recovery. These findings suggest that the effectiveness of transfusion can be enhanced by targeting severely anemic children with cardiorespiratory compromise, improving immediate access to blood, and effective antimalarial therapy. In addition, more information is needed on the causes of death among anemic children and the prevention of severe anemia.

Malaria surveillance--United States, 1993.

PROBLEM/CONDITION: Malaria is caused by infection with one of four species of Plasmodium (P. falciparum, P. vivax, P. ovale, and P. malariae), which are transmitted by the bite of an infective female Anopheles sp. mosquito. Most malaria cases in the United States occur among persons who have traveled to areas (i.e., other countries) in which disease transmission is ongoing. However, cases are transmitted occasionally through exposure to infected blood products, by congenital transmission, or by local mosquito-borne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations. REPORTING PERIOD COVERED: Cases with onset of illness during 1993. DESCRIPTION OF SYSTEM: Malaria cases confirmed by blood smear are reported to local and/or state health departments by health-care providers and/or laboratories. Case investigations are conducted by local and/or state health departments, and the reports are transmitted to CDC. RESULTS: CDC received reports of 1,275 cases of malaria in persons in the United States and its territories who had onset of symptoms during 1993; this number represented a 40% increase over the 910 malaria cases reported for 1992. P. vivax, P. falciparum, P. ovale, and P. malariae were identified in 52%, 36%, 4%, and 3% of cases, respectively. The species was not determined in the remaining 5% of cases. The 278 malaria cases in U.S. military personnel represented the largest number of such cases since 1972; 234 of these cases were diagnosed in persons returning from deployment in Somalia during Operation Restore Hope. In New York City, the number of reported cases increased from one in 1992 to 130 in 1993. The number of malaria cases acquired in Africa by U.S. civilians increased by 45% from 1992; of these, 34% had been acquired in Nigeria. The 45% increase primarily reflected cases reported by New York City. Of U.S. civilians who acquired malaria during travel, 75% had not used a chemoprophylactic regimen recommended by CDC for the area in which they had traveled. Eleven cases of malaria had been acquired in the United States: of these cases, five were congenital; three were induced; and three were cryptic, including two cases that were probably locally acquired mosquito-borne infections. Eight deaths were associated with malarial infection. INTERPRETATION: The increase in the reported number of malaria cases was attributed to a) the number of infections acquired during military deployment in Somalia and b) complete reporting for the first time of cases from New York City. ACTIONS TAKEN: Investigations were conducted to collect detailed information concerning the eight fatal cases and the 11 cases acquired in the United States. Malaria prevention guidelines were updated and disseminated to health-care providers. Persons who have a fever or influenza-like illness after returning from a malarious area should seek medical care, regardless of whether they took antimalarial chemoprophylaxis during their stay. The medical evaluation should include a blood smear examination for malaria. Malaria can be fatal if not diagnosed and treated rapidly. Recommendations concerning prevention and treatment of malaria can be obtained from CDC.

Evaluation of an algorithm for integrated management of childhood illness in an area of Kenya with high malaria transmission.

In 1993, the World Health Organization completed the development of a draft algorithm for the integrated management of childhood illness (IMCI), which deals with acute respiratory infections, diarrhoea, malaria, measles, ear infections, malnutrition, and immunization status. The present study compares the performance of a minimally trained health worker to make a correct diagnosis using the draft IMCI algorithm with that of a fully trained paediatrician who had laboratory and radiological support. During the 14-month study period, 1795 children aged between 2 months and 5 years were enrolled from the outpatient paediatric clinic of Siaya District Hospital in western Kenya; 48% were female and the median age was 13 months. Fever, cough and diarrhoea were the most common chief complaints presented by 907 (51%), 395 (22%), and 199 (11%) of the children, respectively; 86% of the chief complaints were directly addressed by the IMCI algorithm. A total of 1210 children (67%) had Plasmodium falciparum infection and 1432 (80%) met the WHO definition for anaemia (haemoglobin < 11 g/dl). The sensitivities and specificities for classification of illness by the health worker using the IMCI algorithm compared to diagnosis by the physician were: pneumonia (97% sensitivity, 49% specificity); dehydration in children with diarrhoea (51%, 98%); malaria (100%, 0%); ear problem (98%, 2%); nutritional status (96%, 66%); and need for referral (42%, 94%). Detection of fever by laying a hand on the forehead was both sensitive and specific (91%, 77%). There was substantial clinical overlap between pneumonia and malaria (n = 895), and between malaria and malnutrition (n = 811). Based on the initial analysis of these data, some changes were made in the IMCI algorithm. This study provides important technical validation of the IMCI algorithm, but the performance of health workers should be monitored during the early part of their IMCI training.

PIP: The World Health Organization (WHO) in 1993 developed the integrated management of childhood illness (IMCI) draft algorithm which offers guidelines upon the diagnosis and treatment of acute respiratory infections, diarrhea, malaria, measles, ear infections, and malnutrition, as well as immunization status. During a 14-month study period, 1795 children aged 2 months to 5 years were enrolled in the study from the outpatient pediatric clinic of Siaya District Hospital in western Kenya, of whom 52% were male and the median age was 13 months. 51% of the children complained of having fever, 22% of having a cough, and 11% of having diarrhea. 86% of the main complaints were directly addressed by the IMCI algorithm. 1210 children had Plasmodium falciparum infection and 1432 met the WHO definition for anemia. The sensitivities and specificities for classification of illness by a minimally trained health worker using the IMCI algorithm compared to diagnosis by the physician were: pneumonia, 97% sensitivity and 49% specificity; dehydration in children with diarrhea, 51% and 98%, respectively; malaria, 100% and 0%; ear problem, 98% and 2%; nutritional status, 96% and 66%; and need for referral, 42% and 94%. Detection of fever by placing a hand upon the forehead was 91% sensitive and 77% specific. Considerable clinical overlap was observed between pneumonia and malaria, and between malaria and malnutrition. Study findings led to some changes in the IMCI algorithm.

Assessment of potential indicators for protein-energy malnutrition in the algorithm for integrated management of childhood illness.

Potential indicators were assessed for the two classifications of protein-energy malnutrition in the guidelines for integrated management of childhood illness: severe malnutrition, which requires immediate referral to hospital, and very low weight, which calls for feeding assessment, nutritional counselling and follow-up. Children aged < 2 years require feeding assessment and counselling as a preventive intervention. For severe malnutrition, we examined 1202 children admitted to a Kenyan hospital for any association of the indicators with mortality within one month. Bipedal oedema indicating kwashiorkor, and two marasmus indicators (visible severe wasting and weight-for-height (WFH) Z-score of < -3) were associated with a significantly increased mortality risk (odds ratios, 3.1-3.9). Very low weight-for-age (WFA) (Z-score of < -4.4) was not associated with an increased risk of mortality. Because first-level health facilities generally lack length-boards, bipedal oedema and visible severe wasting were chosen as indicators of severe malnutrition. To assess potential WFA thresholds for the very low weight classification, our primary source of data came from 1785 Kenyan outpatient children, but we also examined data from surveys in Nepal, Bolivia, and Togo. We examined the performance of WFA at various thresholds to identify children with low WFH and, for children aged < or = 2 years, low height-for-age (HFA). Use of a WFA threshold Z-score of < -2 identified a considerable proportion of children (from 13% in Bolivia to 68% in Nepal) which, in most settings, would pose an enormous burden on the health facility. Among ill children in Kenya, a threshold WFA Z-score of < -3 had a sensitivity of 89-100% to detect children with WFH Z-scores of < -3, and, with an identification rate of 9%, would avoid overburdening the clinics. Potential modifications include use of a more restrictive cut-off in countries with high rates of stunting, or the elimination of the WFA screen in order to concentrate efforts on intervention for all children below the 2-year age cut-off. Key issues in every country include the capacity to provide counselling for many children and linkage to nutritional improvement programmes in the community.

PIP: Severe malnutrition and very low weight were assessed as potential indicators for the classification of protein-energy malnutrition in the guidelines for the integrated management of childhood illness. For severe malnutrition, the authors examined 1202 children under age 5 years admitted to a Kenyan hospital for any association of the indicators with mortality within 1 month. Bipedal oedema indicating kwashiorkor, and the marasmus indicators of visible severe wasting and a weight-for-height (WFH) Z score of less than -3 were associated with a significantly increased risk of mortality. Very low weight-for-age (WFA) was not associated with an increased risk of mortality. Bipedal edema and visible severe wasting were chosen as indicators of severe malnutrition since first-level health facilities typically lack length-boards. Data for 1785 Kenyan outpatient children as well as survey data from Nepal, Bolivia, and Togo were used in assessing potential WFA thresholds for the very low weight classification. Use of a WFA threshold Z-score of less than -2 identified from 13% of children in Bolivia to 68% in Nepal who would in most settings burden health facilities. Among sick children in Kenya, a threshold WFA Z-score of less than -3 was 89-100% sensitive in detecting children with WFH Z-scores of less than -3 and, with an identification rate of 9%, would not overburden health clinics. Potential modifications include the use of a more restrictive cutoff in countries with high rates of stunting or the elimination of the WFA screen in order to focus efforts upon intervention for all children under the 2-year age cutoff.

Clinical signs for the recognition of children with moderate or severe anaemia in western Kenya.

Optimal treatment of Plasmodium falciparum-related paediatric anaemia can result in improved haematological recovery and survival. Clinical predictors are needed to identify children with anaemia in settings where laboratory measurements are not available. The use of conjunctival (eyelid), palmar, nailbed, and tongue pallor to detect children with moderate anaemia (haemoglobin, 5.0-7.9 g/dl) or severe anaemia (haemoglobin, < 5.0 g/dl) was evaluated among children seen at an outpatient and inpatient setting in a hospital in western Kenya. Severe nailbed or severe palmar pallor had the highest sensitivity (62% and 60%, resp.), compared with severe conjunctival pallor (sensitivity = 31%), to detect children with severe anaemia in the outpatient setting. Children with moderate anaemia were best identified by the presence of nailbed or palmar pallor (sensitivity = 90% for both signs), compared with conjunctival pallor (sensitivity = 81%). Clinical signs of respiratory distress, in addition to the presence of severe pallor, did not increase the recognition of children requiring hospitalization for severe anaemia. Among inpatients, the sensitivity of severe nailbed pallor (59%) was highest for detecting children with severe anaemia, although the sensitivity of severe conjunctival pallor and severe palmar pallor was the same (53% for both signs). Presence of conjunctival pallor (sensitivity = 74%) was similar in sensitivity to both nailbed and palmar pallor (70% for both signs) among children with moderate anaemia. The sensitivity of tongue pallor was low among all children evaluated. Low haemoglobin levels were significantly associated with the likelihood of being smear-positive for P. falciparum. This study demonstrates that clinical criteria can be used to identify children with moderate and severe anaemia, thus enabling implementation of treatment algorithms. Children aged < 36 months who live in an area with P. falciparum malaria should receive treatment with an effective antimalarial drug if they have pallor.

PIP: The ability of pallor of the conjunctiva, palms, nailbed, and tongue to identify children with Plasmodium falciparum-related anemia in developing country settings, where laboratory measurements are not available, was investigated in children attending Siaya District Hospital in western Kenya. Enrolled were all children 2 months to 5 years of age admitted to the hospital's inpatient unit in 1993-94 (n = 1048), and every fifth child presenting to the outpatient clinic (n = 1666). Severe nailbed or severe palmar pallor had the highest sensitivities (62% and 60%, respectively) in the detection of severe anemia in outpatients, while those with moderate anemia were best identified by nailbed or palmar pallor (90% sensitivity for both signs). The addition of clinical signs of respiratory distress to pallor did not increase the identification of children requiring hospitalization for severe anemia. Among inpatients, severe nailbed, conjunctival, and palmar pallor had sensitivities of 59%, 53%, and 53%, respectively, for detecting severe anemia. In the detection of moderate anemia, the sensitivities were 74%, 70%, and 70%, respectively, for conjunctival, nailbed, and palmar pallor. Tongue pallor had a low sensitivity among all children examined. Low hemoglobin levels were significantly associated with P. falciparum infection. It is recommended that all children under 36 months of age, in areas with P. falciparum malaria, should receive antimalarial treatment if they present with pallor.

Childhood mortality during and after hospitalization in western Kenya: effect of malaria treatment regimens.

Plasmodium falciparum infection is an important cause of the high childhood mortality rates in sub-Saharan Africa. Increasingly, the contribution of P. falciparum-associated severe anemia to pediatric mortality is being recognized while the impact of chloroquine resistance on mortality has not been evaluated. To address the issues of pediatric mortality, causes of death among hospitalized children less than five years of age in western Kenya were identified using standardized clinical examinations and laboratory evaluations. Follow-up examinations were conducted to determine the child's clinical status posthospitalization. Of the 1,223 children admitted to Siaya District Hospital from March to September 1991, 293 (24%) were severely anemic (hemoglobin level < 5.0 g/dL). There were 265 (22%) deaths; 121 (10%) occurred in-hospital and 144 (13%) occurred out-of-hospital within eight weeks after admission; 32% of all deaths were associated with malaria. Treatment for malaria with chloroquine was associated with a 33% case fatality rate compared with 11% for children treated with more effective regimens (pyrimethamine/sulfa, quinine, or trimethoprim/sulfamethoxazole for five days). The risk of dying was associated with younger age (P < 0.0001) and severe anemia (relative risk [RR] = 1.52, 95% confidence interval [CI] = 1.22, 1.90), and was decreased by treatment with an effective antimalarial drug (RR = 0.33, 95% CI = 0.19, 0.65). Effective drug therapy for P. falciparum with regimens that are parasitocidal in areas with a high prevalence of severe anemia and chloroquine resistance can significantly improve the survival of children in Africa.

PIP: Plasmodium falciparum infection is an important cause of the high childhood mortality rates in sub-Saharan Africa. Causes of death among hospitalized children less than age 5 years in western Kenya were identified using standardized clinical examinations and laboratory evaluations. Follow-up examinations were then conducted to determine the child's clinical status posthospitalization. 293 of the 1223 children admitted to Siaya District Hospital during March-September 1991 were severely anemic. 265 children died; 32% of the deaths were associated with malaria. 121 of the deaths occurred in-hospital and 144 out-of-hospital within 8 weeks after admission. The treatment of malaria with chloroquine was associated with a 33% case fatality rate compared with 11% for children treated with more effective regimens of pyrimethamine/sulfa, quinine, or trimethoprim/sulfamethoxazole for 5 days. The risk of dying was associated with younger age and severe anemia, and was decreased by treatment with an effective antimalarial drug.

Field detection of sulfonamides in urine: the development of a new and sensitive test.

A new, field-adapted, colorimetric method for detecting sulfonamide drugs in urine is described. The method uses the color reagent, p-dimethylaminocinnamaldehyde, and has a detection limit of about 1 microgram/ml. Analysis of 35 samples collected in the field, comparing results obtained with the colorimetric field test with those obtained using high-performance liquid chromatography, indicated a calculated sensitivity value of 94% and a specificity value of 94% for the test to detect the presence of sulfonamides. The field test can be modified to allow quantitation of sulfonamides in urine in field situations, using a hand-held, portable photometer for measuring the absorbance of test solutions. For this test, calculated coefficients of variation for day to day reproducibility were < or = 5% at sulfonamide concentrations > or = 3 micrograms/ml. This new test for detecting the presence of sulfonamides in urine is more sensitive and reliable than the presently used Bratton-Marshall test.

Changing patterns of autochthonous malaria transmission in the United States: a review of recent outbreaks.

Three recent outbreaks of locally acquired malaria in densely populated areas of the United States demonstrate the continued risk for mosquitoborne transmission of this disease. Increased global travel, immigration, and the presence of competent anopheline vectors throughout the continental United States contribute to the ongoing threat of malaria transmission. The likelihood of mosquitoborne transmission in the United States is dependent on the interactions between the human host, anopheline vector, malaria parasite, and environmental conditions. Recent changes in the epidemiology of locally acquired malaria and possible factors contributing to these changes are discussed.

Malaria surveillance--United States, 1992.

PROBLEM/CONDITION: Malaria is caused by one of four species of Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae) and is transmitted by the bite of an infective female Anopheles sp. mosquito. Most malaria cases in the United States occur among persons who have traveled to areas that have ongoing transmission. However, cases are transmitted occasionally through exposure to infected blood products, by congenital transmission, or by local mosquito-borne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations. REPORTING PERIOD COVERED: Cases with onset of illness during 1992. DESCRIPTION OF SYSTEM: Malaria cases were identified at the local level (i.e., by healthcare providers or through laboratory-based surveillance). All suspected cases were confirmed by slide diagnosis and then reported to the respective state health department and to CDC. RESULTS: CDC received reports of 910 cases of malaria that had onset of symptoms during 1992 among persons in the United States and its territories. In comparison, 1,046 cases were reported for 1991, representing a decrease of 13% in 1992. P. vivax, P. falciparum, P. malariae, and P. ovale were identified in 51%, 33%, 4%, and 3% of cases, respectively. The species was not identified in the remaining 9% of cases. The number of reported malaria cases that had been acquired in Africa by U.S. civilians decreased 38%, primarily because the number of P. falciparum cases declined. Of U.S. civilians whose illnesses were diagnosed as malaria, 81% had not taken a chemoprophylactic regimen recommended by CDC. Seven patients had acquired their infections in the United States. Seven deaths were attributed to malaria. INTERPRETATION: The decrease in the number of P. falciparum cases in U.S. civilians could have resulted from a change in travel patterns, reporting errors, or increased use of more effective chemoprophylaxis regimens. ACTIONS TAKEN: Additional information was obtained concerning the seven fatal cases and the seven cases acquired in the United States. Malaria prevention guidelines were updated and disseminated to health-care providers. Persons traveling to a malaria-endemic area should take the recommended chemoprophylaxis regimen and use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently develops a fever or influenza-like symptoms should seek medical care, which should include a blood smear for malaria. The disease can be fatal if not diagnosed and treated at an early stage of infection. Recommendations concerning prevention and treatment of malaria can be obtained from CDC.

Mosquito-transmitted malaria in New York City, 1993.

In August, 1993, 3 cases of Plasmodium falciparum malaria in people without recent travel histories or bloodborne exposure were reported in New York City. An epidemiological investigation confirmed the absence of risk factors for acquisition of malaria in two cases. The third case could not be definitively classified as locally acquired malaria because the patient had travelled to Thailand two years before malaria was diagnosed. The 3 individuals lived in separate houses in the same neighbourhood of Queens, New York and had onset of illness within a day of each other. The investigation consisted of patient interviews, active case finding, reviewing recent New York flight and shipping arrivals, and an entomological survey for anopheline mosquitoes and breeding sites. No other cases were identified. The 3 patients lived several miles from air and sea ports and prevailing winds would have carried any mosquitoes at those sites away from the patient's homes. By the time of the environmental investigation (September, 1993), the area was dry and neither adult nor larval anophelines were found. However, weather conditions at the probable time of infection (July, 1993) were very different. Malaria was probably transmitted to these 2 patients by local anopheline mosquitoes that had fed on infected human hosts. Mosquito-control measures were not implemented because there was no evidence of ongoing transmission. The occurrence of mosquito-transmitted malaria in New York City demonstrates the potential for reintroduction of malaria transmission into areas that are no longer endemic and emphasises the need for continued surveillance and prompt investigations, if cases without risk factors are reported.

Anaemia, blood transfusion practices, HIV and mortality among women of reproductive age in western Kenya.

Severe anaemia among women in sub-Saharan Africa is frequently treated with blood transfusions. The risk of transmission of human immunodeficiency virus (HIV) through blood products has led to a re-evaluation of the indications for transfusions. Prospective surveillance of women admitted to a district hospital in western Kenya was conducted from 1 December 1990 to 31 July 1991, for haemoglobin (Hb) transfusion status, and outcome. Of the 2986 enrolled women (mean Hb 10.4 g/dL, SD +/- 2.6, median age 24.4 years), 6% were severely anaemic (Hb < 6.0 g/dL). Severe anaemia was associated with a higher mortality rate (10.7% vs. 1.4%, odds ratio (OR) = 8.2, 95% confidence interval (CI) 2.6, 34.2) compared with women with Hb > or = 6.0 g/dL. Decreased mortality rates in hospital were observed with increasing Hb values (OR = 0.43, 95% CI 0.19, 0.98), but blood transfusions did not improve survival in hospital (OR = 1.56, 95% CI 0.22, 11.03). The attributable mortality due to HIV infection and severe anaemia was 75% and 31%, respectively. Maternal/child health care services must include prevention strategies for HIV transmission and the prevention, recognition, and treatment of severe anaemia.

PIP: This paper reports the findings of an evaluation of Western Kenyan blood transfusion practices used with a cohort of severely anemic women of child-bearing age. The potential of receiving HIV-infected blood puts these women at a definite health risk. Characteristics of severely anemic women included being older (P = 0.03, Wilcoxon rank sum test), lower likelihood of being pregnant when admitted to hospital (odds ratio [OR] = 0.53; 95% confidence interval [CI], 0.35-0.81), and greater likelihood of being HIV seropositive (OR = 2.92; 95% CI, 1.52-5.60) when compared to non-anemic women. Severely anemic women were also less likely to have malaria (OR = 0.58; 95% CI, 0.35-0.96). Women who had a transfusion ordered had a higher mortality rate than women who did not (25/240, 10.4% vs. 18/933, 1.9%)(OR = 5.91; 95% CI, 3.04-11.53). In this study, positive benefits were restricted to women who had a transfusion only for them. These were the severely anemic women. The attributed mortality caused by HIV infection and severe anemia was 75% and 31%, respectively. Detection of HIV infected blood is very critical. Prevention of anemia is considered more important than transfusing concerns. Preventing the need for transfusions would reduce the HIV transmission risk from potentially infectious blood during transfusion.

Malaria. Principles of prevention and treatment.

In the United States, effective malaria prevention strategies for short-term travelers are available. Monitoring trends in imported malaria and continued evaluation of the effectiveness and chemoprophylaxis will allow prevention recommendations to evolve as the risk of infection and effectiveness of antimalarial drugs change. Our challenge is to increase the number of prospective travelers receiving pre-travel advice, to disseminate this information to health care providers, and to improve the quality of the advice given. The early recognition of Plasmodium infection and the institution of prompt and effective treatment will reduce morbidity and mortality from malaria in this country.

Clonidine improves perioperative myocardial ischemia, reduces anesthetic requirement, and alters hemodynamic parameters in patients undergoing coronary artery bypass surgery.

The purpose of this study was to determine if clonidine reduces myocardial ischemia or alters anesthetic requirement and perioperative hemodynamic parameters during coronary artery bypass grafting (CABG) surgery. Forty-three patients were randomized in a prospective, double-blind fashion to receive either clonidine (5 micrograms/kg) or placebo. Anesthetic induction and maintenance was accomplished with intravenous sufentanil-midazolam (S-M) in a 1:20 ratio; up to 1.0% enflurane was added during surgery when repeated boluses of S-M failed to maintain the blood pressure within 20% of preinduction values. Continuous ST segment analysis of leads II and V5 was performed throughout surgery with maximal ST segment deflection from baseline recorded every 5 minutes. Catecholamine levels were measured intermittently throughout the perioperative period and myocardial lactate use or excretion was determined just prior to cardiopulmonary bypass (CPB) and at 1, 5, 10, 30, and 60 minutes after release of the aortic cross-clamp. Patients who received clonidine required significantly less sufentanil for their surgical procedure (11.82 +/- 0.66 micrograms/kg v 14.55 +/- 0.90 micrograms/kg, P < 0.05) and also needed less enflurane for blood pressure control, particularly during CPB (P < 0.05). Baseline hemodynamic parameters were similar for both groups prior to induction. In the period between anesthetic induction and the initiation of CPB, patients treated with clonidine had a significantly slower heart rate (HR) (P < 0.01), a lower cardiac output (CO) (P < 0.05), and transiently higher systemic vascular resistance (SVR) (P < 0.05) than placebo-treated patients. Immediately after CPB, patients receiving clonidine continued to have a significantly lower CO (P < 0.01) and a higher SVR (P < 0.01) than placebo-treated patients. Clonidine treatment significantly increased the percentage of patients who required pacing after CPB (P < 0.05). In the intensive care unit, clonidine-treated patients displayed a persistently increased requirement for pacing (P < 0.01), decreased systolic blood pressures, and reduced sodium nitroprusside requirements relative to patients treated with placebo. Epinephrine and norepinephrine levels were lower in clonidine-treated patients throughout the perioperative procedure with significant differences noted immediately following sternotomy and release of the aortic cross-clamp (P < 0.05). Critical ST segment depression was significantly less in clonidine-treated patients for the period from sternotomy until application of the aortic cross-clamp (P < 0.01). Following CPB, absolute deviation of ST segments from isoelectric baseline was significantly less in the clonidine-treated group (P < 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)