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1.
Int J Tuberc Lung Dis ; 4(10): 968-74, 2000 Oct.
Article de Anglais | MEDLINE | ID: mdl-11055765

RÉSUMÉ

SETTING: Queen Elizabeth Central Hospital, Blantyre, and Zomba Central Hospital, Zomba, Malawi. OBJECTIVE: To follow-up human immunodeficiency virus (HIV) seropositive and HIV-seronegative patients with smear-negative pulmonary tuberculosis (PTB) and pleural TB who had completed treatment with two different regimens in Blantyre and Zomba, and to assess rates of mortality and recurrent TB. DESIGN: Patients with smear-negative and pleural TB who had completed 8 months ambulatory treatment in Blantyre or 12 months standard treatment in Zomba and who were smear and culture negative for acid-fast bacilli at the completion of treatment were actively followed every 4 months for a total of 20 months. RESULTS: Of 248 patients, 150 with smear-negative PTB and 98 with pleural TB, who completed treatment and were enrolled, 205 (83%) were HIV-positive. At 20 months, 145 (58%) patients were alive, 85 (34%) had died and 18 (7%) had transferred out of the district. The mortality rate was 25.7 per 100 person-years, with increased rates strongly associated with HIV infection and age >45 years. Forty-nine patients developed recurrent TB. The recurrence rate of TB was 16.1 per 100 person-years, with increased rates strongly associated with HIV infection, having smear-negative PTB and having received 'standard treatment'. CONCLUSION: High rates of mortality and recurrent TB were found in patients with smear-negative PTB and pleural effusion during 20 months of follow-up. TB programmes in sub-Saharan Africa must consider appropriate interventions, such as co-trimoxazole and secondary isoniazid prophylaxis, to reduce these adverse outcomes.


Sujet(s)
Antituberculeux/usage thérapeutique , Infections à VIH/complications , Épanchement pleural/microbiologie , Tuberculose pulmonaire/mortalité , Adulte , Femelle , Études de suivi , Infections à VIH/microbiologie , Humains , Sujet immunodéprimé , Malawi/épidémiologie , Mâle , Adulte d'âge moyen , Récidive , Tests sérologiques , Tuberculose pulmonaire/complications
2.
Ann Trop Med Parasitol ; 93(3): 231-7, 1999 Apr.
Article de Anglais | MEDLINE | ID: mdl-10562824

RÉSUMÉ

A hospital-based, prospective study was undertaken at Mangochi District Hospital (MDH) and Kamuzu Central Hospital (KCH) in Malawi. The malaria-transmission patterns in the catchment areas of these two hospitals are very different, transmission being continuous around MDH and seasonal, occurring mostly during the rainy season, around KCH. The main purpose of the study was to determine and compare the prevalences of cerebral malaria (CM) among young, hospitalized children (aged < 5 years) at both sites. Among 8600 of such children admitted to the two hospitals, the overall prevalence of CM was 2.3% (2.2% at KCH and 2.5% at MDH). The prevalences of CM on admission were similar at the two sites during the rainy season (at 3.2%), but the prevalence at MDH during the dry season was statistically higher than that at KCH over the same period (2.1% v. 1.0%; P = 0.0078). A nearly significant difference was noted between the two sites in the prevalences of parasitaemia on admission (11.9% at KCH v. 9.2% at MDH; P = 0.07), and of severe malarial anaemia (SMA) on admission (5.4% at KCH v. 4.2% at MDH; P = 0.06). No inter-site differences were noted in the prevalences of CM or SMA when analysed by mean age, weight, haemoglobin, body temperature, weight-for-age Z-scores, duration of hospitalization, or proportion with high parasite score on admission. These findings differ from those by researchers in other parts of sub-Saharan Africa, where the prevalence of CM has been found to be higher in areas with seasonal transmission patterns. It appears that the epidemiology of CM can differ within the same country, with location and season. Whenever possible, therefore, plans to control CM in any sub-Saharan country should be based on locally generated data.


Sujet(s)
Paludisme cérébral/épidémiologie , Paludisme à Plasmodium falciparum/épidémiologie , Saisons , Analyse de variance , Animaux , Enfant d'âge préscolaire , Climat , Femelle , Humains , Paludisme cérébral/parasitologie , Malawi/épidémiologie , Mâle , Plasmodium falciparum , Prévalence , Études prospectives , Statistique non paramétrique
3.
Int J Tuberc Lung Dis ; 3(5): 402-8, 1999 May.
Article de Anglais | MEDLINE | ID: mdl-10331729

RÉSUMÉ

SETTING: Queen Elizabeth Central Hospital, Blantyre, and Zomba Central Hospital, Zomba, Malawi. OBJECTIVE: To evaluate treatment outcome of unsupervised ambulatory treatment (2R3H3Z3/2TH[EH]/4H) in Blantyre and 'standard' treatment (1STH[SEH]/11TH[EH]) in Zomba in human immunodeficiency virus (HIV) seropositive and seronegative patients with smear-negative pulmonary tuberculosis (PTB) and pleural TB. DESIGN: All patients with smear-negative and pleural TB registered between 1 April and 31 December 1995 were assessed for enrolment in the study. Study patients were followed up and 12-month treatment outcomes were recorded. RESULTS: A total of 434 patients, 296 with smear-negative PTB and 138 with pleural TB, were enrolled: 366 (84%) of patients were HIV-positive; 220 (51%) completed treatment, and 144 (33%) died by 12 months. In patients from Blantyre and Zomba, baseline characteristics were similar, apart from older age in those from Zomba, and the proportion of patients who completed treatment and who died were similar. In both sites, significantly higher case fatality rates were found in older patients, HIV-positive patients and patients with pulmonary parenchymal lung disease. CONCLUSION: Unsupervised ambulatory treatment evaluated in this study had an efficacy similar to that of 'standard' treatment. For operational reasons, however, it will not be recommended for widespread use in Malawi's National Tuberculosis Control Programme.


Sujet(s)
Soins ambulatoires , Antituberculeux/usage thérapeutique , Tuberculose pleurale/traitement médicamenteux , Tuberculose pulmonaire/traitement médicamenteux , Adolescent , Adulte , Femelle , Humains , Malawi , Mâle , Adulte d'âge moyen , Facteurs de risque , Expectoration/microbiologie , Analyse de survie , Résultat thérapeutique , Tuberculose pulmonaire/mortalité , Tuberculose pulmonaire/prévention et contrôle
4.
AIDS ; 13(4): 487-94, 1999 Mar 11.
Article de Anglais | MEDLINE | ID: mdl-10197377

RÉSUMÉ

OBJECTIVES: This study was undertaken to determine the relative effect of malaria infection on HIV concentration in blood plasma, and prospectively to monitor viral concentrations after antimalarial therapy. DESIGN: A prospective, double cohort study was designed to compare the blood HIV-1 RNA concentrations of HIV-positive individuals with and without acute malaria illness. Subjects were followed for 4 weeks after successful malaria therapy, or for 4 weeks from enrollment (controls). METHODS: Malawian adults with symptomatic Plasmodium falciparum parasitemia (malaria group) and asymptomatic, aparasitemic blood donors (control group) were tested for HIV-1 antibodies to identify appropriate study groups. The malaria group received antimalarial chemotherapy only and were followed with sequential blood films. In both groups, blood plasma HIV-1 RNA viral concentrations were determined at enrollment and again at 1, 2 and 4 weeks. RESULTS: Forty-seven malaria patients and 42 blood donors were enrolled. At enrollment blood plasma HIV-1 RNA concentrations were approximately sevenfold higher in patients with malaria than in blood donors (medians 15.1 x 10(4) and 2.24 x 10(4) copies/ml, respectively, P = 0.0001). No significant changes in median HIV-1 concentrations occurred in the 21 blood donors followed to week 4 (P = 0.68). In the 27 subjects successfully treated for malaria who were followed to week 4, a reduction in plasma HIV-1 RNA was observed from a median of 19.1 x 10(4) RNA copies/ml at enrollment, to 12.0 x 10(4) copies/ml at week 4, (P = 0.02). Plasma HIV-1 concentrations remained higher in malaria patients than controls (median 12.0 x 10(4) compared with 4.17 x 10(4) copies/ml, P = 0.086). CONCLUSIONS: HIV-1 blood viral burden is higher in patients with P. falciparum malaria than in controls and this viral burden can, in some patients, be partly reduced with antimalarial therapy.


Sujet(s)
Infections opportunistes liées au SIDA/virologie , VIH-1 (Virus de l'Immunodéficience Humaine de type 1) , Paludisme à Plasmodium falciparum/virologie , Charge virale , Infections opportunistes liées au SIDA/traitement médicamenteux , Adulte , Animaux , Femelle , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/génétique , Humains , Paludisme à Plasmodium falciparum/traitement médicamenteux , Mâle , Études prospectives , ARN viral/sang
5.
Int J Tuberc Lung Dis ; 2(12): 999-1004, 1998 Dec.
Article de Anglais | MEDLINE | ID: mdl-9869116

RÉSUMÉ

SETTING: Queen Elizabeth Central Hospital, Blantyre, Malawi. OBJECTIVES: 1) To determine the proportion of pulmonary tuberculosis (PTB) suspects with negative sputum smears and a normal/minimally abnormal chest radiograph (CXR) who are culture-positive for Mycobacterium tuberculosis, and 2) to determine how many develop smear or radiographic evidence of PTB (TB CXR) during follow-up. METHODS: PTB suspects with negative sputum smears and a normal/minimally abnormal CXR were given a second course of antibiotics and followed up at 3-week intervals over 3 months with repeat sputum smears and chest radiography. RESULTS: Of 79 patients (38 men and 41 women, mean age 33 years) with negative smears and a normal/minimally abnormal CXR, 16 (21%) were culture-positive for M. tuberculosis. Of 15 culture-positive patients who were alive and attended follow-up, seven (47%) developed a TB-CXR by 3 months. Of 41 culture-negative patients who were alive and attended follow-up, 13 (32%) developed a TB-CXR, including one patient who became sputum smear-positive. TB-CXRs were found only in patients with a cough. CONCLUSION: TB suspects with negative smears and normal/minimally abnormal CXRs in high human immunodeficiency virus (HIV) prevalent countries should be given a second course of antibiotics. If cough improves, patients can be advised not to return for further follow-up. If cough continues, patients should return for further follow-up with sputum smear examination and chest radiography. Approximately 50% of those who have culture-positive PTB will develop a TB-CXR by 3 months and can be identified if radiographic facilities are available.


Sujet(s)
Pays en voie de développement , Tuberculose pulmonaire/thérapie , Adulte , Antituberculeux/usage thérapeutique , Femelle , Humains , Malawi , Mâle , Expectoration/microbiologie , Tuberculose pulmonaire/diagnostic , Tuberculose pulmonaire/traitement médicamenteux
6.
Trans R Soc Trop Med Hyg ; 92(3): 343-7, 1998.
Article de Anglais | MEDLINE | ID: mdl-9861414

RÉSUMÉ

There is little information about treatment outcome in patients with smear-negative pulmonary tuberculosis (PTB) or extrapulmonary tuberculosis (EPTB) treated under routine programme conditions in subsaharan Africa. A prospective study was carried out to determine treatment outcome in an unselected cohort of TB patients admitted to Zomba General Hospital, Malawi. Eight hundred and twenty-seven adult TB patients (451 men and 376 women) were registered between 1 July and 31 December 1995. Standardized treatment outcomes of treatment completion, death, default, and transfer to another district were assessed in relation to type of TB, human immunodeficiency virus (HIV) serostatus, age and gender. Two hundred and fifty-four patients (31%) died by the end of treatment, half of the deaths occurring in the first month. Death rates were 19% among 386 patients with smear-positive PTB, 46% among 211 patients with smear-negative PTB, and 37% among 230 patients with EPTB; 77% of the patients were HIV seropositive. Among new patients, HIV-positive patients had higher death rates than HIV-negative patients (hazard ratio [HR] 2.5; 95% confidence interval [95% CI] 1.6-3.8). Smear-negative patients had the highest death rates (HR 3.9; 95% CI 2.7-5.5 compared to smear-positive patients), followed by EPTB patients (HR 2.6, 95% CI 1.8-3.7 compared to smear-positive patients). Death rates increased with age but were similar in men and women. Adult patients in Malawi with smear-negative PTB and EPTB have low treatment completion and high death rates, related to high levels of HIV infection. National TB control programmes in areas of high HIV prevalence should no longer ignore treatment outcomes in patients with smear-negative PTB or EPTB.


Sujet(s)
Antituberculeux/usage thérapeutique , Infections à VIH/mortalité , Tuberculose/mortalité , Adulte , Études de cohortes , Femelle , Infections à VIH/complications , Infections à VIH/traitement médicamenteux , Humains , Malawi/épidémiologie , Mâle , Adulte d'âge moyen , Études prospectives , Résultat thérapeutique , Tuberculose/complications , Tuberculose/traitement médicamenteux
7.
Trans R Soc Trop Med Hyg ; 92(2): 161-3, 1998.
Article de Anglais | MEDLINE | ID: mdl-9764320

RÉSUMÉ

The prevalence of pulmonary tuberculosis (PTB) in patients with short duration of cough was determined. Ninety-eight adult out-patients (60 men, 38 women; mean age 32 years) at Queen Elizabeth Central Hospital, Blantyre, Malawi, who had cough for 1-3 weeks which was unresponsive to a course of antibiotics, were successfully screened by microscopy and culture of 2 or 3 sputum specimens and chest radiography; 34 (35%) had PTB. Ten patients were sputum smear-positive and 24 were smear-negative and culture-positive. There was no difference in age, gender or clinical features of general illness, respiratory disease and HIV-related disease between patients with PTB and those with no evidence of PTB. Nine patients (26%) with microbiologically confirmed tuberculosis (TB) had chest radiograph abnormalities consistent with TB, compared with 5 (8%) of patients with no microbiological evidence of TB. Certain classes of patients with a short history of cough would benefit from PTB screening strategies with the emphasis on sputum examination rather than chest radiography, which is unreliable in such patients. The classes include (i) patients with other features of TB whose cough has not improved with antibiotic therapy, (ii) seriously ill patients, and (iii) patients in high risk institutions such as prisons and refugee camps.


Sujet(s)
Toux/microbiologie , Tuberculose pulmonaire/complications , Adulte , Toux/épidémiologie , Femelle , Humains , Malawi/épidémiologie , Mâle , Mycobacterium tuberculosis/isolement et purification , Prévalence , Expectoration/microbiologie , Facteurs temps , Tuberculose pulmonaire/épidémiologie
8.
Trans R Soc Trop Med Hyg ; 91(4): 416-9, 1997.
Article de Anglais | MEDLINE | ID: mdl-9373637

RÉSUMÉ

Alternative strategies for screening tuberculosis (TB) suspects are needed in sub-saharan Africa. Ambulatory adult TB suspects who were seen in the chronic cough room of Queen Elizabeth Central Hospital, Blantyre, Malawi, were assessed with respect to appropriateness of referral. Appropriate referrals (patients with cough 3 weeks or longer, weight loss and no antibiotic response) were screened by 3 sputum specimens for microscopy and culture of Mycobacterium tuberculosis and chest radiography (CXR). Hypothetical strategy A (screening by sputum smear examination followed by CXR in patients with negative sputum smears) was compared with strategy B (screening by CXR followed by sputum smear examination in patients with a CXR consistent with TB) in terms of diagnostic efficacy and cost. Of 1127 patients referred to the cough room, 402 (38%) were appropriate TB suspect referrals. Of these, 111 (28%) were sputum smear-positive, 213 (53%) were culture-positive, and 221 (55%) had smear and/or culture-positive evidence of TB. Routine CXR was consistent with pulmonary (P) TB in 230 patients (57%). With strategy A, 243 (60%) patients were diagnosed as PTB, but 40 (25%) of those not diagnosed as PTB had positive mycobacterial cultures. With strategy B, 230 patients (57%) were diagnosed as PTB, but 53 (31%) of those not diagnosed as PTB had positive mycobacterial cultures, including 13 with smear-positive sputum. The cost per diagnosed case of PTB was US$ 4.63 with strategy A and US$ 5.44 with strategy B. Screening patients with good criteria of TB has high diagnostic sensitivity, but screening by CXR is less effective and more costly than screening by sputum smear microscopy.


Sujet(s)
Expectoration/microbiologie , Tuberculose pulmonaire/diagnostic , Adolescent , Adulte , Économie médicale , Femelle , Humains , Malawi , Mâle , Mycobacterium tuberculosis/isolement et purification , Radiographie thoracique
9.
Ann Trop Med Parasitol ; 91(7): 771-6, 1997 Oct.
Article de Anglais | MEDLINE | ID: mdl-9625933

RÉSUMÉ

Malawi is similar to a number of other African countries in having an escalating, HIV-related, tuberculosis (TB) epidemic. A prospective study was carried out to determine the pattern of disease and HIV serostatus in unselected, adult, TB patients consecutively admitted to a large, district general hospital in Zomba (in the Southern region of Malawi). Clinical details were obtained, from the district TB register, for the 714, adult TB patients, aged > or = 15 years, who were registered with the district TB officer between 1 July and 31 December in 1995. Patients were counselled, and offered HIV testing using an ELISA and particle agglutination test. Concordant HIV-test results were available for 686 (96%) of the subjects: 547 (80%) of these were HIV-seropositive and 139 seronegative. The HIV-positive patients were significantly younger than the HIV-negative patients and significantly more HIV-positive patients were males (P < 0.05 for each). The proportions of HIV-positive subjects who were new patients, had been previously treated for TB, had pulmonary TB (PTB), had smear-positive PTB or had different types of extrapulmonary TB were similar to those of the HIV-negative. A high percentage of an unselected cohort of adult TB patients admitted to a district, general hospital in Malawi, particularly of the younger age groups was therefore HIV-positive. The pattern of disease was uninfluenced by the HIV serostatus. The large number of cases registered emphasises the severity of the current epidemic of TB in Malawi and its impact upon young adults.


Sujet(s)
Infections opportunistes liées au SIDA/épidémiologie , Tuberculose/épidémiologie , Infections opportunistes liées au SIDA/complications , Adolescent , Adulte , Répartition par âge , Sujet âgé , Études de cohortes , Femelle , Humains , Malawi/épidémiologie , Mâle , Adulte d'âge moyen , Études prospectives , Répartition par sexe , Tuberculose/complications
10.
Trop Med Int Health ; 1(2): 231-5, 1996 Apr.
Article de Anglais | MEDLINE | ID: mdl-8665390

RÉSUMÉ

In March 1993, sulphadoxine/pyrimethamine (SP) replaced chloroquine as the first line drug for malaria treatment in Malawi. Since then, the Ministry of Health has been receiving anecdotal and written reports of SP treatment failures in children. To determine whether treatment failure with SP was a widespread problem, children < 5 years of age with axillary temperature > 38.0 degrees C and parasite density > 2000/mm3 attending the outpatient clinics of the Mangochi and Karonga District Hospitals were enrolled in the study with parental consent. These were then followed for 28 days or until they failed clinically. Of 159 patients enrolled, 145 (91.2%) were followed for 28 days or until clinical failure. Of these, none had RII resistance and 3 (1.9%) had RIII resistance: 2/69 (2.9%) in Mangochi and 1/76 (1.3%) in Karonga; 142/145 (97.9%) exhibited RI/sensitive patterns. Of those followed to day 28 or to clinical failure, 77.1% had parasite clearance by day 3 and 98.6% had parasite clearance by day 7. Of those with temperature readings (n = 140), 129 (92.1%) clinically improved on day 3 and 98.6% improved by day 7. Other indicators of clinical improvement (from day 0 to day 3) included, reported increased level of activity in 136 (97.1%) of the children, and mother's impression of child's improvement in 113 (80.7%). Of the 14 patients not followed to day 28 or to clinical failure, 11 were lost to follow-up by day 7. No allergic skin reactions were noted, and no deaths were observed. These data show that after one year of widespread use of SP in Malawi, Plasmodium falciparum parasite resistance remains very low, and therefore contradicts reports of widespread parasite resistance to SP.


Sujet(s)
Antipaludiques/usage thérapeutique , Paludisme à Plasmodium falciparum/traitement médicamenteux , Pyriméthamine/usage thérapeutique , Sulfadoxine/usage thérapeutique , Facteurs âges , Enfant d'âge préscolaire , Association médicamenteuse , Résistance aux substances , Études de suivi , Humains , Nourrisson , Paludisme à Plasmodium falciparum/parasitologie , Malawi , Échec thérapeutique
11.
Am J Trop Med Hyg ; 55(1 Suppl): 17-23, 1996.
Article de Anglais | MEDLINE | ID: mdl-8702032

RÉSUMÉ

The problems of Plasmodium falciparum infection in pregnant women have been described in numerous sub-Saharan African countries, but the frequency of parasitemia at the first antenatal visit and risk factors for infection have not been fully investigated. During a prospective antimalarial treatment and prophylaxis trial in pregnant women in Malawi (three groups receiving a chloroquine regimen and one group receiving a mefloquine regimen), we examined women at their first antenatal clinic visit to evaluate these issues and to verify that subjects in the study treatment/prevention arms were similar. Among 4,127 women with enrollment blood smear results, 1,836 (44.5%) were parasitemic. The highest infection rates and densities were observed in primigravidas (66% infected, geometric mean parasite density [GMPD] = 1,588 parasites/mm3 of whole blood), followed by second pregnancies (46% infected, GMPD = 615 parasites/mm3) and subsequent pregnancies (29% infected, GMPD = 238 parasites/mm3), (P < 10(-6) for both infection prevalence and density, by chi-square test for trend). Significant risk factors for parasitemia at first antenatal clinic visit in a multivariate model included low gravidity, high transmission season, no use of prophylaxis before first antenatal clinic visit, young age (< 20 years), human immunodeficiency virus (HIV) infection, low hematocrit, short stature, and second trimester (compared with third trimester). Women in the different treatment arms of the study were generally similar in many characteristics; statistically significant differences, where present, were small. Targeting malaria control efforts to women in their first or second pregnancy and during the high transmission season will be an important strategy to reach most parasitemic women and minimize resource expenditure. Women infected with HIV had a 55% increased risk of parasitemia at their first antenatal clinic visit and may represent an additional important risk group whose numbers may be increasing and who may benefit from identification and management for malaria.


Sujet(s)
Antipaludiques/usage thérapeutique , Chloroquine/usage thérapeutique , Paludisme à Plasmodium falciparum/épidémiologie , Méfloquine/usage thérapeutique , Parasitémie/épidémiologie , Complications parasitaires de la grossesse/épidémiologie , Prise en charge prénatale , Adolescent , Adulte , Femelle , Humains , Paludisme à Plasmodium falciparum/traitement médicamenteux , Paludisme à Plasmodium falciparum/prévention et contrôle , Malawi/épidémiologie , Parasitémie/traitement médicamenteux , Parasitémie/prévention et contrôle , Grossesse , Complications parasitaires de la grossesse/traitement médicamenteux , Complications parasitaires de la grossesse/prévention et contrôle , Études prospectives , Facteurs de risque , Population rurale , Saisons
12.
Am J Trop Med Hyg ; 55(1 Suppl): 2-7, 1996.
Article de Anglais | MEDLINE | ID: mdl-8702033

RÉSUMÉ

Plasmodium falciparum infection in pregnant women frequently leads to placental infection and low birth weight (< 2,500 grams) of the infant, particularly in the areas of high malaria transmission found in sub-Saharan Africa. Low birth weight is widely known to be an important risk factor for early infant mortality. To reduce the risk that maternal infection poses to child survival, many antenatal clinic programs recommend and provide antimalarial chemoprophylaxis, often with chloroquine (CQ) as a recommended element for antenatal care. Prior to the 1980s, despite widespread advocacy for this intervention, little was known about the effect of this intervention strategy. As an introduction to the Mangochi Malaria Research Project, which examined the efficacy of several antimalarial regimens using CQ or mefloquine in pregnant women in Malawi, we describe the background of knowledge regarding malaria infection in pregnant African women and the important elements of an intervention and prevention strategy.


Sujet(s)
Antipaludiques/usage thérapeutique , Transmission verticale de maladie infectieuse , Paludisme à Plasmodium falciparum/prévention et contrôle , Complications parasitaires de la grossesse/prévention et contrôle , Issue de la grossesse , Afrique subsaharienne , Femelle , Mort foetale , Humains , Immunité acquise d'origine maternelle , Nourrisson à faible poids de naissance , Nouveau-né , Paludisme à Plasmodium falciparum/complications , Paludisme à Plasmodium falciparum/transmission , Grossesse , Recherche
13.
Am J Trop Med Hyg ; 55(1 Suppl): 24-32, 1996.
Article de Anglais | MEDLINE | ID: mdl-8702034

RÉSUMÉ

Despite international recommendations to use malaria treatment and prevention in pregnant women in malaria-endemic areas, few studies have evaluated the efficacy of available antimalarial regimens. This issue is of particular concern in the face of spreading chloroquine (CQ)-resistance of Plasmodium falciparum in malarious areas of sub-Saharan Africa. In a prospective trial in rural Malawian pregnant women, we examined three regimens using CQ (including the existing national policy regimen) and one regimen using mefloquine (MQ). The efficacy of the regimens was determined by comparing rates of clearance of initial parasitemia; prevention of breakthrough infection; and parasitemia at delivery in maternal peripheral blood, placental blood, and in infant umbilical cord blood. Among 1,528 parasitemic women at enrollment, 281 (18.4%) had persistent infections; and among 1,852 initially aparasitemic women, 320 (17.3%) had breakthrough parasitemia on one or more follow-up visits. Compared with women on MQ, women on a CQ regimen were at significantly greater risk of persistent and breakthrough infection (odds ratios [OR] = 30.9 and 11.1, respectively, P < 10(-6)). Other significant risk factors for persistent and breakthrough infections in a multivariate model included first pregnancy; enrollment in the rainy or postrainy season; maternal age < or = 25 years; seropositivity to the human immunodeficiency virus (HIV) (persistent infections only); and no use of antimalarial prophylaxis before enrollment (breakthrough infections only). At delivery, compared with women on MQ, women on a CQ regimen were at significantly greater risk of peripheral, placental, or umbilical cord blood parasitemia (OR = 8.7, 7.4, and 4.1, respectively, P < 10(-6)). Additional risk factors for parasitemia at delivery in multivariate models included first pregnancy; delivery in the rainy or postrainy season; HIV-seropositivity; and maternal age < or = 25 years (risk for peripheral and placental blood parasitemia only). Maternal anemia (hematocrit < 30%) at enrollment or at delivery was not associated with persistent or breakthrough parasitemia or parasitemia at deliver in these multivariate models. While factors leading to increased malaria parasite exposure (high transmission seasons) and lowered or altered host immune response (low pregnancy number, young age, and HIV infection) are important risk factors for malaria in pregnant women, the use of an ineffective intervention (CQ in a setting with CQ-resistant parasites) was the most important determinant of P. falciparum parasitemia in these pregnant women. Strategies to reduce the impact of malaria in pregnant women must use efficacious interventions and may need to consider targeting the intervention to the most susceptible women during the seasons of high malaria exposure.


PIP: During September 1987 to June 1990, 3380 pregnant women with parasitemia attending 4 prenatal care clinics in rural Mangochi District, Malawi, were assigned to 1 of 4 regimens of antimalarial treatment and/or prophylaxis. The women were followed through delivery to determine the antimalarial drug efficacy on peripheral parasitemia during pregnancy and parasitemia at the time of delivery in peripheral, placental, and umbilical cord blood. The regimens were 3 regimens for chloroquine (CQ), 1 of which was the current standard of care in Malawi, and a mefloquine (MQ) regimen. Parasite clearance was not achieved in 18.4% of the 1528 women with parasitemia at enrollment. 17.3% of the 1852 women who were aparasitemic at enrollment had breakthrough infections. Women using a CQ regimen faced a significantly greater risk of persistent and breakthrough parasitemia (odds ratio [OR ] = 30.9 and 11.1, respectively; p 0.0000001). The multivariate analysis found other significant risk factors for malaria to be first pregnancy (OR = 3.6 for persistent malaria and 1.5 for breakthrough malaria), enrollment in the rainy or post-rainy season (OR = 2-3.4 for persistent parasitemia and 1.2-2.7 for breakthrough malaria), maternal age of at most 25 years (OR = 2.3 for persistent malaria and 1.6 for breakthrough malaria), and seropositivity to HIV (OR = 1.9 for persistent malaria). At delivery, women on a CQ regimen faced a significantly higher risk of peripheral, placental, or umbilical cord parasitemia than those using MQ (OR = 8.7, 7.4, and 4.1, respectively; p 0.000001). In the multivariate model, other significant risk factors for malaria at delivery were first pregnancy, enrollment in the rainy or post-rainy season, maternal age of at most 25 years, and seropositivity to HIV. The most important determinant of falciparum malaria in pregnant women was use of an ineffective intervention (i.e., CQ in an area with CQ-resistant parasites). Based on these findings, the researchers recommend that antimalarial programs focus on highly efficacious drugs and targeting pregnant women during the season of high malaria exposure.


Sujet(s)
Antipaludiques/usage thérapeutique , Chloroquine/usage thérapeutique , Paludisme à Plasmodium falciparum/épidémiologie , Méfloquine/usage thérapeutique , Complications du travail obstétrical/épidémiologie , Parasitémie/épidémiologie , Maladies du placenta/épidémiologie , Complications parasitaires de la grossesse/épidémiologie , Adolescent , Adulte , Femelle , Sang foetal/parasitologie , Humains , Paludisme à Plasmodium falciparum/traitement médicamenteux , Malawi/épidémiologie , Complications du travail obstétrical/traitement médicamenteux , Parasitémie/traitement médicamenteux , Maladies du placenta/traitement médicamenteux , Grossesse , Complications parasitaires de la grossesse/traitement médicamenteux , Études prospectives , Population rurale , Résultat thérapeutique
14.
Am J Trop Med Hyg ; 55(1 Suppl): 33-41, 1996.
Article de Anglais | MEDLINE | ID: mdl-8702035

RÉSUMÉ

While there is broad evidence for the adverse effects of Plasmodium falciparum infection in pregnancy, and the World Health Organization recommends preventive strategies, there is markedly reduced efficacy in sub-Saharan Africa of the most widely available, affordable and used antimalarial drug for chemoprophylaxis-chloroquine (CQ). During 1987-1990, we studied pregnant women in an area of high malaria endemicity in rural Malawi to compare the efficacy of CQ (the drug recommended by national policy) with mefloquine (MQ, a relatively new and highly effective antimalarial) in preventing low birth weight (LBW) due to prematurity and intrauterine growth retardation (IUGR). Among 1,766 women monitored during at least their last six weeks of pregnancy with observed ingestion of their regimen and facility delivery of a live born singleton, their babies had a mean +/- SD birth weight of 2,905 +/- 461 gm and 16.8% had LBW. In a multivariate analysis, factors significantly associated with LBW included: first birth (odds ratio [OR] = 4.27), female infant (OR = 2.92), maternal human immunodeficiency virus infection (OR = 2.66), low maternal weight (OR = 1.95), and placental blood P. falciparum infection (OR = 1.71). Factors significantly associated with IUGR-LBW included first birth, female infant, low maternal weight, and placental malaria. Factors significantly associated with preterm-LBW included maternal syphilis infection, umbilical cord blood malaria, first birth, low maternal weight, and female infant. Use of an effective antimalarial (MQ) was protective against LBW through its effect on reducing placental and umbilical cord blood malaria infection. The proportion of LBW babies born to women on MQ (12.5% [parity-adjusted for the population of delivering women]) was significantly lower than the proportion born to women on CQ (15.5%; P = 0.05). Effective prevention of malaria in pregnant women in malaria-endemic settings may reduce the likelihood of LBW by 5-14%, and may reduce the amount of preventable LBW by more than 30%. When evaluating antenatal care programs, health policy makers must consider providing an effective preventive drug (either MQ or other drugs identified in additional studies, e.g., sulfa-pyrimethamine compounds) as a means to prevent low birth weight and its consequences.


Sujet(s)
Antipaludiques/usage thérapeutique , Chloroquine/usage thérapeutique , Nourrisson à faible poids de naissance , Paludisme à Plasmodium falciparum/prévention et contrôle , Méfloquine/usage thérapeutique , Complications parasitaires de la grossesse/prévention et contrôle , Adolescent , Adulte , Femelle , Retard de croissance intra-utérin/épidémiologie , Humains , Nouveau-né , Prématuré , Paludisme à Plasmodium falciparum/épidémiologie , Malawi/épidémiologie , Grossesse , Complications parasitaires de la grossesse/épidémiologie , Facteurs de risque , Population rurale , Résultat thérapeutique
15.
Am J Trop Med Hyg ; 55(1 Suppl): 42-9, 1996.
Article de Anglais | MEDLINE | ID: mdl-8702036

RÉSUMÉ

In Africa, the human immunodeficiency virus (HIV) is the most serious emerging infection and Plasmodium falciparum malaria is one of the most prevalent infectious diseases. Both infections have serious consequences in pregnant women, their fetuses, and infants. We examined the association between HIV and P. falciparum in pregnant women enrolled in a malaria chemoprophylaxis study in rural Malawi. Pregnant women (n = 2,946) were enrolled at their first antenatal clinic visit (mean 5.6 months of pregnancy), placed on one of three chloroquine regimens, and followed through delivery. Plasmodium falciparum parasitemia was measured at enrollment, monthly thereafter, at delivery, and 2-6 months postpartum; placental and newborn (umbilical cord blood) infection was measured for hospital-delivered infants. Serum collected during pregnancy was tested for antibodies to HIV by enzyme-linked immunoassay with Western blot confirmation. Parasitemia was detected in 46% of 2,946 women at enrollment and 19.1% at delivery; HIV seroprevalence was 5.5%. The prevalence and geometric mean density (GMPD) of parasitemia at enrollment and at delivery were higher in HIV-seropositive(+) than in HIV-seronegative(-) women (at enrollment: 57% prevalence and a GMPD of 1,558 parasites/mm3 versus 44% and 670/mm3, respectively; P < 0.0001; and at delivery: 35% and 1,589/mm3 versus 18% and 373/mm3; P < 0.0005). Placental infection rates were higher in HIV(+) compared with HIV(-) women, (38% versus 23%; P < 0.0005). This association was strongest in multigravidas. Compared with infants born to HIV(-) women, newborns born to HIV(+) women had higher rates of umbilical cord blood parasitemia. Both HIV(+) and HIV(-) women had similar rates of parasitemia 2-6 months postpartum. The HIV infection diminishes a pregnant woman's capacity to control P. falciparum parasitemia and placental and newborn infection, the major determinants of the impact of P. falciparum on fetal growth and infant survival.


PIP: During September 1987 to July 1989, in Malawi, clinical investigators enrolled 2946 pregnant women into a chemoprophylaxis study at their first prenatal care visit (mean, 5.6 months) at 4 rural sites in Mangochi District. They prescribed 1 of 3 chloroquine regimens to the women and followed them through delivery. The investigators measured Plasmodium falciparum parasitemia at enrollment, monthly thereafter, at delivery, and 2-6 months postpartum. For hospitalized infants, they measured parasitemia in the placenta and in the umbilical cord blood of the newborn. They also aimed to examine the association between HIV infection and malaria in pregnant women. 152 (5.5%) of the 2781 women for whom HIV test results and malaria blood smear examinations were available had confirmed HIV infection. Malaria parasitemia stood at 42% at enrollment and 19.1% at delivery. At enrollment, HIV-positive women had a higher malaria parasite prevalence rate than HIV-negative women (54.4% vs. 41.7%; relative risk [RR] = 1.31; p = 0.002). They also had a higher geometric mean density of parasitemia (1558 vs. 670/sq mm; p 0.0005). The parasite pattern was similar at delivery (34.7% vs. 18.2% [RR = 1.91] and 1589 vs. 373/sq mm, respectively; p 0.0005). The placenta of infants born in the hospital to HIV-positive mothers also had a higher prevalence of malaria parasites than those born in the hospital to HIV-negative mothers (38.2% vs. 22.5%; RR = 1.7; p = 0.0003). The prevalence of umbilical cord blood malaria infection was higher in infants born in the hospital to HIV-positive mothers than their counterparts (25.5% vs. 6.8%; RR = 3.76). At 2-6 months postpartum, the prevalence and density of malaria parasitemia rate did not differ significantly by HIV status. Parasitemia prevalence and density were higher in multigravida HIV-positive women than HIV-negative women but were similar in primigravid HIV-positive and HIV-negative women. These findings suggest that HIV infection reduces a pregnant woman's capacity to control P. falciparum parasitemia and placental and newborn infection.


Sujet(s)
Antipaludiques/usage thérapeutique , Chloroquine/usage thérapeutique , Sang foetal/parasitologie , Infections à VIH/complications , VIH-1 (Virus de l'Immunodéficience Humaine de type 1) , Paludisme à Plasmodium falciparum/complications , Complications infectieuses de la grossesse , Adolescent , Adulte , Accouchement (procédure) , Femelle , Humains , Paludisme à Plasmodium falciparum/prévention et contrôle , Malawi/épidémiologie , Maladies du placenta/épidémiologie , Grossesse , Complications infectieuses de la grossesse/prévention et contrôle , Prévalence , Population rurale
16.
Am J Trop Med Hyg ; 55(1 Suppl): 57-60, 1996.
Article de Anglais | MEDLINE | ID: mdl-8702038

RÉSUMÉ

Malaria during pregnancy may result in fetal exposure to malaria when parasites are transmitted across the placenta. To document the rate of transplacental passage of Plasmodium falciparum and to identify the risk factors for congenitally acquired malaria infection, we examined umbilical cord blood for malaria parasites from 2,080 newborn infants born to mothers enrolled in a study of malaria prophylaxis during pregnancy. Cord blood parasitemia was detected in 140 (6.7%) newborn infants with a geometric mean density of 187 parasites/microliter (range 12-99, 752 parasites/microliter). The likelihood of umbilical cord blood parasitemia was closely linked to the parasite density of placental malaria infection and the density of maternal peripheral blood parasitemia at the time of delivery; all babies born to women with both placental and peripheral blood parasitemia densities > or = 10,000/microliter had cord blood parasitemia. In a multivariate logistic regression model, male sex, premature delivery, and placental and maternal peripheral blood malaria parasitemia were independently associated with a baby being born with umbilical cord blood parasitemia. In this setting, highly endemic for malaria, transplacental transmission of malaria from infected placentae occurs frequently and is directly related to the density of maternal malaria infection.


Sujet(s)
Sang foetal/parasitologie , Transmission verticale de maladie infectieuse , Paludisme à Plasmodium falciparum/transmission , Complications parasitaires de la grossesse , Adolescent , Adulte , Antipaludiques/usage thérapeutique , Femelle , Humains , Modèles logistiques , Paludisme à Plasmodium falciparum/prévention et contrôle , Malawi/épidémiologie , Grossesse , Complications parasitaires de la grossesse/prévention et contrôle , Facteurs de risque , Population rurale
17.
Am J Trop Med Hyg ; 55(1 Suppl): 61-5, 1996.
Article de Anglais | MEDLINE | ID: mdl-8702039

RÉSUMÉ

Perinatal deaths (fetal or infant deaths from the 28th week of pregnancy up to the seventh day after birth) occur as a result of adverse conditions during pregnancy, labor, and delivery, or in the first few days of life. Placental malaria infection is known to increase the risk of delivery of a low birth weight infant, thus, potentially increasing the risk of perinatal and infant mortality. To better understand the relationship among the adverse events in pregnancy, including placental malaria infection, adverse conditions in labor, and birth weight to perinatal mortality, we investigated the perinatal mortality among a cohort of infants born to rural Malawian women for whom placental malaria infection status and birth weight were documented. Among the 2,063 mother-singleton infant pairs, there were 111 perinatal deaths (53.8 perinatal deaths per 1,000 births). The risk of perinatal death increased as birth weight decreased. Risk factors identified for perinatal mortality among all infants excluding birth weight included abnormal delivery (cesarean section, breech, or vacuum extraction), a history of a late fetal or neonatal death in the most recent previous birth among multiparous women, reactive maternal syphilis serology, nulliparity, and low socioeconomic status. Placental malaria infection was not associated with increased perinatal mortality, but was associated with lower perinatal mortality among normal birth weight (> or = 2,500 g) infants (odds ratio = 0.35, 95% confidence interval = 0.14, 0.92). Interventions to address these risk factors could have a substantial impact on reducing perinatal mortality in this population.


Sujet(s)
Mortalité infantile , Paludisme à Plasmodium falciparum/épidémiologie , Maladies du placenta/épidémiologie , Complications parasitaires de la grossesse/épidémiologie , Adolescent , Adulte , Femelle , Humains , Nouveau-né , Malawi/épidémiologie , Grossesse , Facteurs de risque , Population rurale
18.
Am J Trop Med Hyg ; 55(1 Suppl): 50-6, 1996.
Article de Anglais | MEDLINE | ID: mdl-8702037

RÉSUMÉ

In sub-Saharan Africa, women frequently report a variety of symptoms during pregnancy, some of which indicate possible illness. Given the adverse impact of malaria in pregnancy, these events may be important for at least two reasons: it may be possible to use reported fever illness as a determinant of which women need an antimalarial intervention, and, it is possible that adverse symptoms following the antimalarial intervention may be important determinants of continued adherence to the prevention regimen. In a cohort of pregnant women enrolled at first antenatal clinic visit in rural Malawi, we evaluated reported fever, determined parasitemia, and placed the women on antimalarial regimens containing chloroquine (CQ) or mefloquine (MQ). We then systematically evaluated reported symptoms following antimalarial drug use after initial therapeutic doses and subsequent prophylactic doses, and monitored women throughout their pregnancy and at delivery. Among 4,187 enrolled women, 1,048 (25%) reported at least one febrile episode during pregnancy before their first antenatal clinic visit. Factors associated with this reported fever included low parity, enrollment in the rainy season, human immunodeficiency virus seropositivity, use of antimalarial prophylaxis before enrollment, high socioeconomic status, normal (compared to low) maternal height and weight, and literacy. Fever before the first antenatal clinic visit was reported by 24.4% of parasitemic women and 25.4% of aparasitemic women; the sensitivity and specificity of fever to identify parasitemic women was 24% and 71%, respectively. In contrast, the sensitivity and specificity of first or second pregnancy to identify parasitemic women was 71% and 57%, respectively. Among women on a CQ or MQ regimen, approximately 60% reported side effects (e.g., itching, dizziness, and gastrointestinal disturbances) after a treatment dose and approximately 25% reported side effects after a prophylactic dose; rates and types of symptoms reported were similar in the CQ and MQ groups. Few serious side effects were observed and rates of fetal loss were low and similar in the groups. Reliance on fever illness will be wholly inadequate to identify parasitemic women; therefore, our findings support existing World Health Organization recommendations that presumptive treatment and prevention regimens should be offered to all pregnant women. When resources are inadequate to offer antimalarial prophylaxis to all pregnant women, women in their first or second pregnancy may be a more appropriate target group than pregnant women with reported fever. Education regarding expected minor side effects may reduce rates of poor compliance and improve the effectiveness of the prevention effort.


PIP: 4187 pregnant women with parasitemia attending 4 prenatal care clinics in rural Mangochi District, Malawi, were assigned to 1 of 4 regimens of antimalarial treatment and/or prophylaxis and followed through delivery. The aim was to examine maternal fever and to evaluate side effects and the frequency of adverse reproductive outcomes for their possible association with malaria or the antimalarial drug regimens. The regimens were 3 regimens for chloroquine (CQ), 1 of which was the current standard of care in Malawi, and a mefloquine (MQ) regimen. 25% of the pregnant women claimed to have had at least 1 febrile episode before their first prenatal care visit. Blood smear tests revealed the parasitemia prevalence rate at enrollment to be 44.4%. The sensitivity of fever to identify parasitemic pregnant women was 24%. Fever's specificity was 71%. Only high density parasitemia (10,000 parasites/sq m) was associated with fever (44.9% vs. 25.4% for no parasitemia; odds ratio [OR] = 2.54; p 0.000001). Other significant factors associated with high fever were low parity, enrollment in the rainy season, HIV seropositivity, use of antimalarial prophylaxis before enrollment, high socioeconomic status, normal maternal height and weight, and literacy. The sensitivity of first or second pregnancy to identify parasitemic women was 71%. Its specificity was 57%. About 60% of women from both CQ and MQ treatment groups had side effects after a treatment dose. About 25% had side effects after a prophylactic dose. The leading side effects were itching, dizziness, and gastrointestinal disturbances. There were few serious side effects. Among all women, the spontaneous abortion rate was 1.2% and the stillbirth rate was 3.9%. Women in the CQ and MQ treatment groups had similar abortion and stillbirth rates. Based on these findings, the researchers concluded that using fever as a means to identify parasitemic women is unreliable. They recommend antimalarial treatment and/or prophylaxis for all pregnant women, but when resources are limited it should be administered to women in their first or second pregnancy.


Sujet(s)
Antipaludiques/usage thérapeutique , Chloroquine/usage thérapeutique , Fièvre/épidémiologie , Paludisme à Plasmodium falciparum/traitement médicamenteux , Méfloquine/usage thérapeutique , Complications parasitaires de la grossesse/traitement médicamenteux , Issue de la grossesse , Adolescent , Adulte , Antipaludiques/effets indésirables , Chloroquine/effets indésirables , Femelle , Mort foetale/épidémiologie , Humains , Paludisme à Plasmodium falciparum/complications , Paludisme à Plasmodium falciparum/prévention et contrôle , Malawi/épidémiologie , Méfloquine/effets indésirables , Parasitémie/épidémiologie , Grossesse , Complications parasitaires de la grossesse/prévention et contrôle , Population rurale
19.
Am J Trop Med Hyg ; 55(1 Suppl): 66-70, 1996.
Article de Anglais | MEDLINE | ID: mdl-8702040

RÉSUMÉ

Maternal mortality has recently received attention as a neglected public health problem in many developing countries where mortality rates are estimated to be 8-200 times those in developed countries. Most maternal mortality estimates in sub-Saharan Africa have used retrospective methods because of the lack of large population-based studies. The Mangochi Malaria Research Project, a trial of antimalarial chemoprophylaxis in pregnant women, provided an opportunity to examine prospectively mortality among the study women. Among 4,053 monitored pregnant women, 27 women were known to have died during pregnancy, labor, delivery and the one-year follow-up period. Three women died during the antenatal period and 12 died within six weeks of delivery for an estimated maternal mortality rate of 370 per 100,000 pregnant women; this rate was consistent with rates reported from retrospective surveys in Malawi. Twelve women died between three and 10 months after delivery, and the mortality rate in this nonmaternal period was estimated to be 341 per 100,000. Mortality rates in the maternal and nonmaternal periods were surprisingly similar. Human immunodeficiency virus type-1 (HIV-1) infection and anemia were strongly associated with death in the nonmaternal period. Mortality among infants of mothers who died was 3.7 times higher than the rate of death among infants born to mothers who survived. This study highlights that for rural Malawian women, pregnancy and delivery are risky periods, that the death of the mother adversely affects the survival of her children, and that HIV and anemia are important contributors to nonmaternal mortality in reproductive-age women. Strategies to reduce mortality among women of child-bearing age in sub-Saharan Africa must focus on decreasing the complications of pregnancy and delivery, and address important preventable causes of death, such as anemia and HIV infection.


Sujet(s)
Mortalité maternelle , Cause de décès , Études de cohortes , Femelle , Humains , Mortalité infantile , Nouveau-né , Malawi/épidémiologie , Grossesse , Études prospectives , Facteurs de risque , Population rurale
20.
Am J Trop Med Hyg ; 55(1 Suppl): 71-6, 1996.
Article de Anglais | MEDLINE | ID: mdl-8702041

RÉSUMÉ

Malaria infection is thought to be relatively infrequent in infants less than 90 days of age in sub-Saharan Africa. In a rural area of Malawi with intense malaria transmission, we examined the occurrence of malaria infection during infancy and risk factors for parasitemia in the first three months of life in the cohort of infants delivered to women in the Mangochi Malaria Research Project. Among 3,915 liveborn singleton infants, 3,432 (87.7%) were seen at least once during infancy (first 12 months of life); of these, malaria blood smear results were available on 2,649 (77.2%). Overall, in a cross-sectional analysis, 23.3% of infants at three months of age were infected with Plasmodium falciparum; this proportion increased to more than 30% during the high transmission season. By the age of 10 months, 60-80% of the infants were infected, depending on the season. Geometric mean parasite density increased each month after two months of age and plateaued at seven months of age. In a life-table analysis, the median time to acquisition of a positive smear was 199 days. Factors independently associated with smear positivity at < 4 months of age included visit during high transmission season (adjusted odds ratio [AOR] = 4.1), maternal smear positivity at the same visit (AOR = 3.5), history of infant fever in the previous two weeks (AOR = 2.8), birth during the rainy season (AOR = 1.7), low socioeconomic status (AOR = 1.6), and low maternal education (AOR = 1.5). The specificity of a recent fever history for malaria infection in early infancy was high (> 70%). Intervention strategies to reduce the risk of early infant infection need to be targeted toward mothers of infants at high risk.


Sujet(s)
Paludisme à Plasmodium falciparum/épidémiologie , Facteurs âges , Études de cohortes , Études transversales , Fièvre/épidémiologie , Fièvre/étiologie , Humains , Nouveau-né , Études longitudinales , Paludisme à Plasmodium falciparum/complications , Malawi/épidémiologie , Parasitémie/épidémiologie , Prévalence , Facteurs de risque , Population rurale , Saisons
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