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1.
J Community Health ; 37(6): 1172-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22752531

RESUMO

Hazardous health-care waste poses a great danger to public health and the environment if it is not properly managed. There is need for health-care workers involved in its management to understand the integral link between human health and environmental health. This study was done to identify gaps in knowledge, attitude and practice among the healthcare workers involved in its management hence endangering public health and polluting the environment. A self administered questionnaire was used in both Kenyatta National Hospital, Nairobi and Moi Teaching and Referral Hospital, Eldoret to clinicians, nurses, laboratory technologists and hospital attendants to identify the gaps with a focus on their knowledge, attitude and practice. It was found that health and safety in health-care waste management, was not included in most of the curricula for training the three healthcare professionals. Most of them acquired this through on-job training from seminars and informally through organized talks at work-places. The hospital attendants had also an opportunity to acquire the knowledge through organized training at work places. The training improved the workers' compliance to hepatitis B vaccinations and use of personal protective equipment when handling health-care waste. There was also reduction on injuries from health-care waste. This study therefore concludes that it is necessary for healthcare workers training curricula to include health and safety issues while managing hazardous health-care waste as well as establishes the need for healthcare institutions to conduct continuing education on health and safety in the management of health-care waste.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Eliminação de Resíduos de Serviços de Saúde , Recursos Humanos em Hospital , Gerenciamento de Resíduos , Atitude do Pessoal de Saúde , Estudos Transversais , Saúde Ambiental , Hospitais de Ensino , Humanos , Quênia , Recursos Humanos em Hospital/psicologia , Encaminhamento e Consulta , Risco
2.
Eur J Clin Nutr ; 63(2): 173-82, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17928808

RESUMO

BACKGROUND/OBJECTIVES: Iron deficiency anemia is a major public health problem in developing countries and may affect school performance and physical work capacity in nonpregnant adolescents, and may increase the risk of anemia during subsequent teenage pregnancies. We assessed the effect of weekly iron (120 mg elemental iron) and vitamin A (25 000 IU) supplementation on hemoglobin, iron status and malaria and nonmalaria morbidity in adolescent schoolgirls. SUBJECTS/METHODS: A total of 279 schoolgirls aged 12-18 years from public primary schools in Kisumu, western Kenya. Double-blind randomized placebo-controlled trial using a factorial design. RESULTS: Five months of iron supplementation was associated with a 0.52 g dl(-1) (0.21, 0.82) greater increase in hemoglobin relative to iron placebo. The effect was only observed in girls with iron deficiency on enrollment (1.34 g dl(-1) (0.79, 1.88)), but not in iron-replete girls (-0.20 g dl(-1) (-0.59, 0.18)). Similar differences in treatment effect were seen between menstruating and nonmenstruating girls. The effect of iron was independent of vitamin A. The baseline prevalence of vitamin A deficiency was low (6.7%) and no sustained increase in hemoglobin was seen with weekly vitamin A (-0.07 g dl(-1) (-0.38, 0.25)). Incidence of malaria parasitemia was higher in the iron than iron-placebo groups (Rate ratio 1.33 (0.94, 1.88)). CONCLUSIONS: Weekly iron supplementation results in substantial increases in hemoglobin concentration in adolescent schoolgirls in western Kenya, which may outweigh possible risks caused by malaria, but only in iron-deficient or menstruating girls and not in iron-replete and nonmenstruating girls.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Suplementos Nutricionais , Hemoglobinas/metabolismo , Ferro/administração & dosagem , Malária/epidemiologia , Vitamina A/administração & dosagem , Adolescente , Anemia Ferropriva/complicações , Anemia Ferropriva/epidemiologia , Criança , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Ferritinas/sangue , Seguimentos , Humanos , Incidência , Quênia/epidemiologia , Parasitemia/epidemiologia , Proteínas de Ligação ao Retinol/metabolismo , Risco , Oligoelementos/uso terapêutico , Deficiência de Vitamina A/complicações , Deficiência de Vitamina A/tratamento farmacológico , Vitaminas/administração & dosagem
3.
Ann Trop Med Parasitol ; 101(4): 281-95, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17524243

RESUMO

Malaria-associated anaemia is a major public-health problem. Although the treatment of uncomplicated, Plasmodium falciparum malaria aims to clear the parasites, relieve the symptoms and permit haematological recovery, data on the impact of antimalarial treatment on haematological recovery are few. Haematological recovery and the prevalence of anaemia were therefore evaluated in 600 Kenyan children with uncomplicated malaria who were randomly assigned to one of three treatment groups. The children were given sulfadoxine-pyrimethamine (SP) on day 0, SP plus artesunate on day 0 (AS1), or SP on day 0 and artesunate on each of days 0-2 (AS3). Haemoglobin (Hb) concentrations were measured on days 0, 7, 14, 21 and 28, with haematological recovery defined as a day-28 Hb concentration of at least 11 g/dl. Only 96 (18%) of the 543 children who were anaemic (i.e. with <11.0 g Hb/dl) at enrolment achieved haematological recovery. The prevalence of anaemia fell from 91% on day 0 to 74% (252/340) by day 28 (P=0.065). Compared with SP alone, neither artesunate regimen resulted in higher Hb concentrations on day 28 (with means of 10.2, 9.9 and 10.2 g/dl for AS3, AS1 and SP, respectively; P=0.254), a higher frequency of haematological recovery (19%, 14% and 20% for AS3, AS1 and SP, respectively; P=0.301) or a greater reduction in the prevalence of anaemia (prevalences in the AS3, AS1 and SP arms falling from 90%, 89% and 93%, respectively, on day 0, to corresponding values of 71%, 82% and 69% on day 28; P=0.40). In fact, between days 0 and 7, the children in the AS3 arm showed a larger drop in mean Hb than the children in the other two treatment arms. In general, haematological recovery was most likely in older children who had mild anaemia at presentation and were parasitologically cured. Overall, the frequencies of haematological recovery were modest and not influenced by the artesunate treatments. Other factors contributing to anaemia need to be explored more fully.


Assuntos
Anemia/epidemiologia , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Malária Falciparum/tratamento farmacológico , Pirimetamina/uso terapêutico , Sesquiterpenos/uso terapêutico , Sulfadoxina/uso terapêutico , Anemia/tratamento farmacológico , Artesunato , Pré-Escolar , Combinação de Medicamentos , Feminino , Humanos , Lactente , Quênia/epidemiologia , Malária Falciparum/complicações , Masculino , Prevalência , Fatores de Risco
4.
Eur J Clin Nutr ; 59(1): 41-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15305179

RESUMO

OBJECTIVE: Nutritional status is an important marker of overall health and linear growth retardation has serious long-term physiological and economic consequences. Approximately 35 and 29% of preschool children in sub-Saharan Africa are stunted and underweight, respectively. There is relatively little information available about the nutritional status in adolescents, the age group with the highest growth velocity after infancy. We conducted a series of cross-sectional surveys to determine the prevalence and main risk groups for malnutrition and to describe the associations between age, sexual maturation and nutritional status in adolescent schoolgirls in western Kenya. DESIGN: Three cross-sectional surveys; one in Mumias, using random sampling in all schools, and two surveys in Asembo, using a multi-stage random sample design. SETTING: Public primary schools in two different rural malaria endemic areas in western Kenya with high levels of malnutrition in preschool children. SUBJECTS: In all, 928 randomly selected adolescent schoolgirls aged 12-18 y. RESULTS: Overall prevalence of stunting and thinness was 12.1 and 15.6%, respectively. Of the total, 2% were severely stunted. Menarche and start of puberty were delayed by approximately 1.5-2 y compared to a US reference population. The prevalence of stunting and thinness decreased with age and mean height for age z-scores converged towards the median of the US reference curve. Girls who had not yet started menstruating were more likely to be stunted than the girls of the same age who were post-menarche. CONCLUSIONS: Stunting and thinness are common in young adolescent schoolgirls in these poor rural settings in western Kenya, but the prevalence decreases with age, providing observational support that children catch up on incomplete growth attained earlier in life due to a maturational delay of 1.5-2 y allowing prolonged growth.


Assuntos
Fenômenos Fisiológicos da Nutrição do Adolescente , Menarca/fisiologia , Desnutrição Proteico-Calórica/epidemiologia , Desnutrição Proteico-Calórica/fisiopatologia , Adolescente , Idade de Início , Criança , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Quênia/epidemiologia , Estado Nutricional , Pobreza , Prevalência , Saúde da População Rural , Índice de Gravidade de Doença
5.
Eur J Clin Nutr ; 58(4): 681-91, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15042138

RESUMO

OBJECTIVE: Anemia is a major public health concern in preschool children and pregnant women in the developing world. While many studies have examined these two at-risk groups, there is a paucity of data on anemia in adolescents living in developing countries in the complex ecologic context of poverty, parasitism, and malnutrition. We evaluated the prevalence, severity, and risk factors of anemia in adolescent schoolgirls in an area with intense malaria transmission in western Kenya. DESIGN: Two cross-sectional surveys were conducted, using a multistage random sample design. SETTING: Public primary schools in an area with intense malaria transmission in western Kenya. SUBJECTS: A total of 648 randomly selected adolescent schoolgirls aged 12-18 y. RESULTS: The prevalence of anemia (Hb <120 g/l) was 21.1%; only one girl had an Hb less than 70 g/l. Ferritin levels were available from a subsample of 206 girls. The prevalence of iron deficiency (ferritin <12 microg/l) was 19.8, and 30.4% of anemic girls were iron deficient. Malaria and schistosomiasis were the main risk factors for anemia in younger girls (12-13 y), while menstruation was the principal risk factor in older girls (14-18 y). CONCLUSIONS: Iron deficiency and anemia in school-attending girls in western Kenya were more prevalent than in developed countries, but considerably less prevalent than in preschool children and pregnant women from the same study area. Our findings are consistent with other recent school-based surveys from western Kenya, but not with recent community- and school-based cross-sectional surveys from other parts of sub-Saharan Africa. It deserves further study to determine if adolescent girls not attending school are at higher risk of anemia.


Assuntos
Anemia Ferropriva/epidemiologia , Adolescente , Adulto , Anemia Ferropriva/classificação , Antropometria , Criança , Intervalos de Confiança , Estudos Transversais , Feminino , Ferritinas/sangue , Helmintíase/epidemiologia , Humanos , Quênia/epidemiologia , Prevalência , Índice de Gravidade de Doença , Classe Social
6.
Ann Nutr Metab ; 47(6): 276-83, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14520023

RESUMO

BACKGROUND: Maternal vitamin A and iron status was investigated among lactating mothers in a rural community in Kenya. The aim of the study was to establish the prevalence and the relationship of these key nutrients to maternal body composition. METHODS: Eighty-eight mothers provided samples of breast milk and blood for determination of breast milk vitamin A, serum retinol and ferritin. Estimators of body composition were based on the mother's weight, height and skinfold measurements. RESULTS: A total of 78.1% women had breast milk retinol <1.05 micromol/l with 38 and 62% having lactated for a period of <4 and >4 months, respectively. Prevalence of severely deficient serum retinol <0.35 micromol/l and ferritin <12 microg/l was 10 and 37%, respectively. Women with serum ferritin <12 microg/l had significantly lower average hemoglobin (p < 0.01), hematocrit (p < 0.01) and serum retinol (p < 0.05). Serum retinol of mothers who had lactated for <4 months was significantly but negatively correlated with total body fat (r = -0.40; p < 0.05). With a lactation period of >4 months a close relationship was found between serum retinol and hemoglobin (r = 0.26; p <0.01), serum retinol and serum ferritin (r = 0.20; p < 0.05), and fat free mass significantly but negatively correlated with breast milk fat (r = -0.27; p < 0.05). Serum retinol in combination with hematocrit significantly affected both maternal hemoglobin (p < 0.01) and serum ferritin (p < 0.01). CONCLUSION: A high prevalence of vitamin A and iron deficiency was observed in this group of lactating women. Low levels of fat mass were directly related to these indicators of malnutrition.


Assuntos
Composição Corporal/fisiologia , Ferritinas/sangue , Lactação/metabolismo , Leite Humano/química , Vitamina A/metabolismo , Adolescente , Adulto , Anemia Ferropriva/epidemiologia , Estudos Transversais , Feminino , Humanos , Quênia/epidemiologia , Pessoa de Meia-Idade , Estado Nutricional , Prevalência , Saúde da População Rural , Estudos Soroepidemiológicos , Vitamina A/sangue , Deficiência de Vitamina A/epidemiologia
7.
Clin Infect Dis ; 33(12): 1968-74, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11700577

RESUMO

We tested tafenoquine (WR 238605), a new long-acting 8-aminoquinoline, for its ability to prevent malaria in an area that is holoendemic for Plasmodium falciparum. In a double-blinded, placebo-controlled, randomized clinical trial in western Kenya, adult volunteers received a treatment course of 250 mg halofantrine per day for 3 days, to effect clearance of preexisting parasites. The volunteers were then assigned to 1 of 4 drug regimens: placebo throughout; 3 days of 400 mg (base) of tafenoquine per day, followed by placebo weekly; 3 days of 200 mg of tafenoquine per day, followed by 200 mg per week; and 3 days of 400 mg of tafenoquine per day, followed by 400 mg per week. Prophylaxis was continued for up to 13 weeks. Of the evaluable subjects (223 of 249 randomized subjects), volunteers who received 400 mg tafenoquine for only 3 days had a protective efficacy of 68% (95% confidence interval [CI], 53%-79%), as compared with placebo recipients; those who received 200 mg per day for 3 days followed by 200 mg per week had a protective efficacy of 86% (95% CI, 73%-93%); and those who received 400 mg for 3 days followed by 400 mg per week had a protective efficacy of 89% (95% CI, 77%-95%). A similar number of volunteers in the 4 treatment groups reported adverse events. Prophylactic regimens of 200 mg or 400 mg of tafenoquine, taken weekly for < or =13 weeks, are highly efficacious in preventing falciparum malaria and are well tolerated.


Assuntos
Aminoquinolinas/uso terapêutico , Antimaláricos/uso terapêutico , Malária Falciparum/prevenção & controle , Adolescente , Adulto , Aminoquinolinas/efeitos adversos , Animais , Antimaláricos/efeitos adversos , Quimioprevenção , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum/efeitos dos fármacos , Resultado do Tratamento
8.
Lancet ; 358(9282): 657-60, 2001 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-11530174

RESUMO

BACKGROUND: During the past decade, developing countries have received limited support for blood safety programmes. The Kenya Ministry of Health did a collaborative multicentre assessment to establish the risk of HIV transmission by transfusion in Kenya, to promote awareness of blood safety issues in this country with a mature HIV epidemic, and to identify methods to reduce the risk of HIV transmission by blood transfusion in Kenya. METHODS: For 12 weeks, from April to July 1994, we collected information and blood samples from all blood donors, and pretransfusion samples were collected from all recipients in six government hospitals in Kenya. Blood donations were collected and screened for HIV according to standard practice in the hospital laboratories. Test results at a reference laboratory were compared with those of the hospital laboratories and risk of transfusion-associated HIV transmission was calculated. FINDINGS: The prevalence of HIV among blood donors was 6.4% (120 of 1877) and varied by hospital (range 2-20%). HIV test results were available for 1290 donor-recipient pairs. Of these, 26 HIV-positive donations were given to HIV-negative patients. We estimate that 2.0% of transfusions transmitted HIV. Problems in the hospitals that contributed to transfusion risk included inconsistent refrigeration, data entry errors, equipment failure, and lack of a quality-assurance programme. INTERPRETATION: A high proportion of blood transfusions transmitted HIV in this high-prevalence area of Africa, primarily because of erroneous laboratory practices. On the basis of these results, the Kenya Ministry of Health introduced a number of practical and inexpensive interventions to improve national blood safety.


Assuntos
Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Reação Transfusional , Bancos de Sangue/normas , Doadores de Sangue , Transfusão de Sangue/normas , Intervalos de Confiança , Países em Desenvolvimento , Anticorpos Anti-HIV/sangue , Infecções por HIV/epidemiologia , Promoção da Saúde , Quênia/epidemiologia , Razão de Chances , Prevalência , Fatores de Risco
9.
Am J Trop Med Hyg ; 65(2): 100-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11508382

RESUMO

We investigated the development and maintenance of proliferative and antibody responses to apical membrane antigen-1 (AMA-1) epitopes in a holoendemic area of western Kenya. Young children (< 10 years), older children (10-17 years), and adults (> or = 18 years) were followed longitudinally for antibody and T-cell responses at 3 time points with an interval of 3-4 months. The proliferative responses against the AMA-1 T epitopes (PL171, PL172, PL173, PL186, PL191, and PL192) were not stable during follow-up; however, response to mycobacterial antigen PPD was highly stable. The responder frequencies were similar in all 3 time points except for epitope PL192. The younger and older children responded more frequently to T-cell epitopes, but the differences were not significant. A positive proliferative response to PL191 was associated with a significantly lower risk of parasitemia at subsequent follow-up (relative risk, 0.5; P = 0.03). The presence of antibody response to B epitopes PL169, PL170, PL173, PL187, and PL192 in one time point was associated with a subsequent response (P = 0.0001-0.008) suggesting a stable response. Younger (P = 0.046) and older children (P = 0.017) more frequently responded to epitope PL169 than did adults, and adults responded more frequently to PL187 than did younger children (P = 0.009). Responses to AMA-1 T-cell epitopes were short lived, and antibody responses were relatively stable.


Assuntos
Antígenos de Protozoários/imunologia , Malária Falciparum/imunologia , Proteínas de Membrana/imunologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , Adolescente , Adulto , Sequência de Aminoácidos , Animais , Anticorpos Antiprotozoários/sangue , Linfócitos B/imunologia , Criança , Estudos de Coortes , Epitopos/imunologia , Humanos , Quênia , Ativação Linfocitária , Dados de Sequência Molecular , Parasitemia/imunologia , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Linfócitos T/imunologia
10.
Am J Trop Med Hyg ; 64(1-2 Suppl): 18-27, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11425174

RESUMO

Although all-cause mortality has been used as an indicator of the health status of childhood populations, such data are sparse for most rural areas of sub-Saharan Africa, particularly community-based estimates of infant mortality rates. The longitudinal follow-up of more than 1,500 children enrolled at birth into the Asembo Bay Cohort Project (ABCP) in western Kenya between 1992 and 1996 has provided a fixed birth cohort for estimating all-cause mortality over the first 5 yr of life. We surveyed mothers and guardians of cohort children in early 1999 to determine survival status. A total of 1,260 households were surveyed to determine the survival status of 1,556 live births (99.2% of original cohort, n = 1,570). Most mothers (66%) still resided but 27.5% had migrated, and 5.5% had died. In early 1999, the overall cumulative incidence of all-cause mortality for the entire 1992-1996 birth cohort was 26.5% (95% confidence interval, 24.1-28.9%). Neonatal and infant mortality were 32 and 176 per 1,000 live births, respectively. These community-based estimates of mortality in the ABCP area are substantially higher than for Kenya overall (nationally, infant mortality is 75 per 1,000 live births). The results provide a baseline description of all-cause mortality among children in an area with intense Plasmodium falciparum transmission and will be useful in future efforts to monitor changes in death rates attributable to control programs for specific diseases (e.g., malaria and HIV/AIDS) in Africa.


Assuntos
Proteção da Criança/estatística & dados numéricos , Nível de Saúde , Mortalidade , Adolescente , Adulto , Distribuição por Idade , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Infecções por HIV/prevenção & controle , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Quênia/epidemiologia , Estudos Longitudinais , Malária/prevenção & controle , Masculino , Mortalidade Materna , Gravidez , Saúde da População Rural/estatística & dados numéricos
11.
J Infect Dis ; 181(5): 1746-52, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10823777

RESUMO

The anti-merozoite surface protein-1 19-kDa IgG (anti-MSP119KD) IgG responses of 33 parasitemic infants, aged 6-14 months, were compared with those of their mothers at the time of the infant's delivery and at the time the infants were sampled; the antimalaria protection associated with these responses was also compared. IgG1 and IgG3 were the predominant subclasses. Infants <300 days old and pregnant mothers had the lowest cytophilic-to-noncytophilic IgG ratio. By 300 days of age, the infants had IgG subclass compositions and levels similar to those of their mothers at the same date. Among infants, older infants with only 1 or 2 detected asexual parasitemias had the highest cytophilic-to-noncytophilic IgG ratio and IgG1 levels. IgG1 level was negatively correlated with protection. The findings suggest that the MSP119KD antibody response develops with age, not with multiple experiences with parasitemia, and, thus, that an antimalaria vaccine strategy for pregnant mothers could delay infants' first parasitemias until they are more capable of mounting a favorable anti-MSP119KD response.


Assuntos
Anticorpos Antiprotozoários/sangue , Imunoglobulina G/sangue , Transmissão Vertical de Doenças Infecciosas , Malária Falciparum/transmissão , Parasitemia/imunologia , Complicações Parasitárias na Gravidez , Envelhecimento , Estudos de Coortes , Feminino , Humanos , Imunoglobulina G/classificação , Lactente , Recém-Nascido , Quênia/epidemiologia , Malária Falciparum/epidemiologia , Parasitemia/epidemiologia , Gravidez , Análise de Regressão , Estações do Ano
12.
Am J Trop Med Hyg ; 62(4): 504-12, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11220768

RESUMO

The relative importance of acute high-density versus persistent low-density Plasmodium falciparum parasitemia in contributing to the public health problem of malarial anemia remains unclear. The Asembo Bay Cohort Project in western Kenya collected monthly hemoglobin (Hb) and parasitologic measurements and biweekly assessments of antimalarial drug use among 942 singleton live births between 1992 and 1996. A mixed-model analysis appropriate for repeated measures data was used to study how time-varying parasitemia and antimalarial drug exposures influenced mean Hb profiles. Incidence of World Health Organization-defined severe malarial anemia was 28.1 per 1,000 person-years. Among children aged less than 24 months, concurrent parasitemia was significantly associated with lower mean Hb, especially when compared to children with no concurrent parasitemia. Increased densities of the 90-day history of parasitemia preceding Hb measurement was more strongly associated with mean Hb levels than concurrent parasitemia density. While the highest quartile of 90-day parasitemia history was associated with lowest mean Hb levels, children in the lowest 90-day exposure quartile still experienced significantly lower Hb levels when compared to children who remained parasitemia-free for the same 90-day period. The results highlight the importance of collecting and analyzing longitudinal Hb and parasitologic data when studying the natural history of malarial anemia.


Assuntos
Anemia/etiologia , Hemoglobinas/análise , Malária Falciparum/sangue , Parasitemia/sangue , Anemia/epidemiologia , Antimaláricos/uso terapêutico , Pré-Escolar , Estudos de Coortes , Humanos , Incidência , Lactente , Recém-Nascido , Quênia/epidemiologia , Estudos Longitudinais , Malária Falciparum/complicações , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Parasitemia/complicações , Parasitemia/tratamento farmacológico , Parasitemia/epidemiologia
13.
Trop Med Int Health ; 4(11): 728-35, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10588766

RESUMO

In large experimental trials throughout Africa, insecticide-treated bednets and curtains have reduced child mortality in malaria-endemic communities by 15%-30%. While few questions remain about the efficacy of this intervention, operational issues around how to implement and sustain insecticide-treated materials (ITM) projects need attention. We revisited the site of a small-scale ITM intervention trial, 3 years after the project ended, to assess how local attitudes and practices had changed. Qualitative and quantitative methods, including 16 focus group discussions and a household survey (n = 60), were employed to assess use, maintenance, retreatment and perceptions of ITM and the insecticide in former study communities. Families that had been issued bednets were more likely to have kept and maintained them and valued bednets more highly than those who had been issued curtains. While most households retained their original bednets, none had treated them with insecticide since the intervention trial was completed 3 years earlier. Most of those who had been issued bednets repaired them, but none acquired new or replacement nets. In contrast, households that had been issued insecticide-treated curtains often removed them. Three (15%) of the households issued curtains had purchased one or more bednets since the study ended. In households where bednets had been issued, children 10 years of age and younger were a third as likely to sleep under a net as were adults (relative risk (RR) = 0. 32; 95% confidence interval (95%CI) = 0.19, 0.53). Understanding how and why optimal ITM use declined following this small-scale intervention trial can suggest measures that may improve the sustainability of current and future ITM efforts.


Assuntos
Roupas de Cama, Mesa e Banho/estatística & dados numéricos , Inseticidas , Manutenção/estatística & dados numéricos , Controle de Mosquitos/métodos , Roupas de Cama, Mesa e Banho/economia , Coleta de Dados , Seguimentos , Humanos , Quênia , Malária/prevenção & controle , Controle de Mosquitos/economia , Tempo
16.
Am J Trop Med Hyg ; 60(4): 635-40, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10348240

RESUMO

A large-scale longitudinal cohort project was initiated in western Kenya in June 1992. The primary purpose of the project was to study Plasmodium falciparum malaria in a highly endemic area using a comprehensive and multidisciplinary approach, which included epidemiology, entomology, and immunology. Between June 1992 and July 1994, pregnant women living in 15 rural villages were identified during a monthly census and 1,164 were enrolled. The women were followed-up throughout their pregnancy and they, along with their newborn infants and direct siblings of the infants' less than 15 years of age, were monitored over time. As of May 1995, 1,017 infants had been born to these women. This paper presents the design and general methodology used in this study and describes the initial experience with intense monitoring of a large population over a prolonged period.


Assuntos
Malária Falciparum/epidemiologia , Complicações Parasitárias na Gravidez/epidemiologia , Pré-Escolar , Estudos de Coortes , Educação , Métodos Epidemiológicos , Feminino , Habitação , Humanos , Lactente , Quênia/epidemiologia , Estudos Longitudinais , Controle de Mosquitos , Gravidez , Resultado da Gravidez , Chuva , Fatores Socioeconômicos
17.
Am J Trop Med Hyg ; 60(4): 641-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10348241

RESUMO

A large-scale longitudinal cohort project was initiated in western Kenya in June 1992. Between June 1992 and July 1994, 1,848 children less than 15 years of age were monitored prospectively for a mean of 236 days. During this period, 12,035 blood smears were examined for malaria and only 34% were found to be negative. Parasite prevalence (all species) decreased with age (from a high of 83% among children 1-4 years old to 60% among children 10-14 years old). Even more dramatic decreases were noted in the prevalence of high density falciparum infection (from 37% among children 12-23 months old to < 1% among 10-14-year-old children) and in clinical malaria (20% to 0.3% in the same age groups). Children < 1 year of age accounted for 55% of all cases of anemia detected. Anemia was consistently associated with high density infection in children < 10 years of age (20% to 210% increased risk relative to aparasitemic children). These results demonstrate the relationship between high-density malaria infection and two clinical manifestations of malarial illness.


Assuntos
Malária Falciparum/epidemiologia , Plasmodium falciparum/isolamento & purificação , Adolescente , Distribuição por Idade , Anemia/complicações , Anemia/epidemiologia , Animais , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Quênia/epidemiologia , Estudos Longitudinais , Malária Falciparum/complicações , Masculino , Parasitemia/parasitologia , Prevalência , Estações do Ano
18.
Am J Trop Med Hyg ; 60(1): 135-41, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9988337

RESUMO

Using a flow cytometry-based parasite growth inhibition assay (GIA) and an antibody-dependent cellular inhibition (ADCI) assay, we have assessed the differential effect and interaction of monocytes, immune sera, and purified immunoglobulins from Kenyan adults on the growth of Plasmodium falciparum parasites in vitro. We found that monocytes from 14 different normal, healthy, non-malaria-exposed donors had varying effects on parasite growth, i.e., inhibition or enhancement of parasitemia, suggesting heterogeneity in anti-parasitic activities of monocytes from individual donors. Twenty-two serum samples collected from clinically immune adults from western Kenya inhibited growth of P. falciparum after 48 hr in culture. In contrast, all IgG preparations, except one, purified from the same serum samples enhanced parasite growth. In ADCI experiments, of the 22 purified IgG samples used, 11 showed ADCI activities with specific growth inhibition (SGI) of more than 10%, with the highest at 27.6%, and the remaining 11 IgG samples had an SGI of less than 10%. Our results also showed that the ratio of IgG1 to IgG3 antibodies, as determined by an indirect immunofluorescence assay, was higher in the high ADCI response group than in the low response group, suggesting that a higher concentration of IgG1 antibodies with a higher IgG1/IgG3 ratio might be associated with ADCI activities. The present study has resulted in the development of simple, reproducible flow cytometry-based GIA and ADCI assays, and also provides baseline information for further investigation of the role of ADCI activity in naturally acquired immune protection against malaria.


Assuntos
Soros Imunes/imunologia , Imunoglobulina G/imunologia , Malária Falciparum/imunologia , Monócitos/imunologia , Plasmodium falciparum/imunologia , Adulto , Animais , Citotoxicidade Celular Dependente de Anticorpos , Feminino , Citometria de Fluxo , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Quênia , Malária Falciparum/parasitologia , Masculino , Parasitemia/imunologia , Parasitemia/parasitologia , Plasmodium falciparum/crescimento & desenvolvimento
19.
Am J Trop Med Hyg ; 61(6): 932-40, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10674673

RESUMO

Anemia is an important public health problem. During very early childhood numerous factors affect hemoglobin (Hb) concentration over time, making single cross-sectional measurements difficult to interpret when studying the natural history of anemia or evaluating anemia control strategies. We analyzed repeated Hb measures contributed by 942 Kenyan children between birth and 48 months of life using a mixed effects model, with a regression spline used to describe the population mean Hb profile, and random intercepts and slopes and first-order autoregressive correlation structure to accommodate the within-individual correlation among the repeated Hb measures. The approach facilitates the study of time-stationary and time-varying covariates that influence Hb in early life. The fitted mean Hb profile obtained from the analytic model is consistent with the observed mean Hb of the study population. Village of residence was associated with greatest difference in mean Hb at time of birth (16 versus 19 g/dL; P < 0.0001). Monthly weight-for-age was also associated with mean Hb after 3 months of age. This is the first description of an analysis strategy specifically for repeated Hb measures collected in a longitudinal field study in Africa. The strategy will facilitate improved study of time-varying covariates thought to influence pediatric anemia.


Assuntos
Anemia/epidemiologia , Anemia/prevenção & controle , Hemoglobinas/análise , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Adolescente , Adulto , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Quênia/epidemiologia , Estudos Longitudinais , Masculino , Modelos Estatísticos , Gravidez , Valores de Referência , Fatores de Tempo
20.
Am J Trop Med Hyg ; 59(5): 808-12, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9840603

RESUMO

Severe childhood malarial anemia is commonly treated using blood transfusion. Although transfusion may decrease short-term mortality, the risk of human immunodeficiency virus (HIV) transmission is considerable in Africa. We constructed a decision tree to weigh the short-term mortality benefit of transfusion against HIV infection risk. Probability estimates were derived from published studies. The base-case was a two-year-old child with a 13.5% mortality risk to be transfused with screened or unscreened blood (1% or 13% HIV contamination risk, respectively), with reduction of mortality to 5.5% by transfusion (odds ratio=2.7), and a 2.4% risk of fatal transfusion complications. A sensitivity analysis was performed to assess the influence of variation in these estimates. If a child developed acquired immunodeficiency syndrome, survival was weighed as one-tenth of normal survival. For the base-case, we found that transfusion with screened blood provided a survival benefit of 5%. In contrast, transfusion with unscreened blood decreased survival by 2%. Patients with a mortality risk < 5% derived no benefit from a transfusion with screened blood. Other important factors for the benefit of transfusion were the effectiveness of transfusion in reducing mortality and the risk of blood contamination. A blood transfusion was clearly beneficial if the mortality risk was high and the risk of contamination was low. Our findings can be used as a basis for a clinical transfusion policy that limits transfusions to situations in which they are likely to be beneficial. This will in turn optimize child survival and prevent unnecessary exposure of low risk children to the transfusion risks.


Assuntos
Anemia/etiologia , Anemia/terapia , Transfusão de Sangue , Técnicas de Apoio para a Decisão , Malária/complicações , África/epidemiologia , Anemia/mortalidade , Criança , Infecções por HIV/transmissão , Humanos , Malária/mortalidade , Fatores de Risco , Reação Transfusional
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