Clinical features of children hospitalized with malaria--a study from Bikaner, northwest India

Severe Plasmodium vivax malaria in adults has been reported from Bikaner (northwestern India) but the reports on children are scanty. This prospective study was done on 303 admitted children of malaria. The diagnosis was done by peripheral blood smear and rapid diagnostic test. Further confirmation of severe P. vivax monoinfection was done by polymerase chain reaction (PCR). The proportion of P. falciparum, P. vivax, and mixed (P. falciparum and P. vivax) infection was 61.01%, 33.99%, and 4.95%, respectively. Severe disease was present in 49.5% (150/303) children with malaria, with the risk greatest among P. vivax monoinfection (63.1% [65/103]) compared with P. falciparum, either alone (42.7% [79/185]; odds ratio [OR] = 2.3 [95% confidence interval (CI) = 1.40-3.76], P = 0.001) or mixed infections (40% [6/15]; OR = 2.57 [95% CI = 0.88-7.48]). In children < 5 years of age, the proportion of severe malaria attributable to P. vivax rose to 67.4% (31/46) compared with 30.4% (14/46) of P. falciparum (OR = 4.7 [95% CI = 2.6-8.6], P < 0.0001) and 2.2% (1/46) of mixed infection (OR = 92 [95% CI = 24.6-339.9], P < 0.0001). The proportion of patients having severe manifestations, which included severe anemia, thrombocytopenia, cerebral malaria, acute respiratory distress syndrome, hepatic dysfunction, renal dysfunction, abnormal bleeding was significantly high in association with P. vivax monoinfection in 0-5 year age group, while the same was significantly high in association with P. falciparum monoinfection in 5-10 year age group. Similarly P. vivax monoinfection had greatest propensity to cause multiorgan dysfunction in 0-5 year age group (34.1% [17/41], P < 0.0001) in comparison to P. falciparum monoinfection, which had similar propensity in 5-10 year age group (36.8% [35/95], P = 0.039). Plasmodium vivax monoinfection was almost equally serious to cause significant mortality in comparison to P. falciparum (case fatality rate of severe P. vivax was 3.9% versus 3.2% of severe P. falciparum malaria; P = 1.0). This study reaffirms the evidence of severe P. vivax malaria in children in Bikaner.     

Epidemiology of malaria in an area of low transmission in central India

A longitudinal study on malaria was carried out from 2003 to 2005 in an area of unstable malaria in the Panna district in central India. Both Plasmodium vivax and P. falciparum were prevalent; however, the risk of P. falciparum malaria was 31.6% (95% confidence interval [CI] = 29.6-33.6%), which is four times higher compared with that of P. vivax malaria (7.8%, 95% CI = 6.7-9%). An increasing trend was recorded in malaria prevalence from 30.2% in 2003 to 46.6% in 2004 (odds ratio [OR] = 2.0, 95% CI = 1.6-2.5) that increased to 58.6% in 2005 (OR = 1.6, 95% CI = 1.2-2.1). This increase was statistically significant (chi(2) = 120.5, degrees of freedom = 2, P < 0.0001). Anopheles culicifacies was the dominant vector of malaria and showed partial (< 50%) resistance to DDT, which indicated that DDT can still be used. Improved access to treatment facilities, combination therapy, and vector control appears to be the most promising method for controlling malaria in this region.     

Thrombocytopenia in Plasmodium falciparum, Plasmodium vivax and mixed infection malaria: a study from Bikaner (Northwestern India)

The occurrence, relation and magnitude of thrombocytopenia in different species of malaria are not clearly defined. This study included 1,064 patients admitted with malaria to study thrombocytopenia (platelet count <150,000 /cumm) in Plasmodium falciparum (Pf) and Plasmodium vivax (Pv) mono infection and mixed infection (Pf?+?Pv). The species diagnosis was done by peripheral blood film (PBF) and rapid diagnostic test (RDT). Validation by polymerase chain reaction (PCR) was done only in patients with severe thrombocytopenia (platelet count <20,000 /cumm). The breakup of patients was 525 (49.34%) Pf, 460 (43.23%) Pv and 79 (7.42%) mixed malaria (Pf?+?Pv). Thrombocytopenia was observed in 24.6% (262/1064) patients. The risk was greatest in the mixed infections in comparison to monoinfection individually (43.04% [34/79]; mixed vs Pv monoinfection: Odds Ratio [OR]?=?1.675 [95% Confidence Interval (CI) 1.029-2.726], p?相似文献   

Travel histories as risk factors in the analysis of urban malaria in Colombia

Self-reported travel histories were used in a case-control study to determine whether movement of local residents to neighboring endemic areas was a risk factor for malaria in the town of Quibdo, Colombia. Multivariate analyses showed that among residents of Quibdo, traveling to an endemic area 8-14 days before disease onset was the strongest risk factor for both Plasmodium falciparum (adjusted odds ratio [OR] = 28.96, 95% confidence interval [CI] = 13.9-60.32) and P. vivax (adjusted OR = 14.24, 95% CI = 5.27-38.46) malaria. For P. falciparum, individuals who did not travel outside Quibdo during the 8-14 days before disease onset, but who reported traveling 1-7, 15-21, or 22-30 days before disease onset also had an increased risk of malaria. Conversely, use of protection against mosquitoes was negatively associated with P. falciparum. These results highlight the need for malaria control measures that target mobile populations. A definition of imported malaria that allows distinction of imported from autochthonous cases in Quibdo town is proposed.     

Demographic risk factors for severe and fatal vivax and falciparum malaria among hospital admissions in northeastern Indonesian Papua

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

Efficacy of monthly tafenoquine for prophylaxis of Plasmodium vivax and multidrug-resistant P. falciparum malaria

We assessed monthly doses of tafenoquine for preventing Plasmodium vivax and multidrug-resistant P. falciparum malaria. In a randomized, double-blind, placebo-controlled study, 205 Thai soldiers received either a loading dose of tafenoquine 400 mg (base) daily for 3 days, followed by single monthly 400-mg doses (n = 104), or placebo (n = 101), for up to 5 consecutive months. In volunteers completing follow-up (96 tafenoquine and 91 placebo recipients), there were 22 P. vivax, 8 P. falciparum, and 1 mixed infection. All infections except 1 P. vivax occurred in placebo recipients, giving tafenoquine a protective efficacy of 97% for all malaria (95% confidence interval [CI], 82%-99%), 96% for P. vivax malaria (95% CI, 76%-99%), and 100% for P. falciparum malaria (95% CI, 60%-100%). Monthly tafenoquine was safe, well tolerated, and highly effective in preventing P. vivax and multidrug-resistant P. falciparum malaria in Thai soldiers during 6 months of prophylaxis.     

Malaria prevalence and associated risk factors in Eritrea

A parasitological cross-sectional survey was undertaken from September 2000 through February 2001 to estimate the prevalence of malaria parasitemia in Eritrea. A total of 12,937 individuals from 176 villages were screened for both Plasmodium falciparum and Plasmodium vivax parasite species using the OptiMal Rapid Diagnostic Test. Malaria prevalence was generally low but highly focal and variable with the proportion of parasitemia at 2.2% (range: 0.4% to 6.5%). Despite no significant differences in age or sex-specific prevalence rates, 7% of households accounted for the positive cases and 90% of these were P. falciparum. Multivariate regression analyses revealed that mud walls were positively associated with malaria infection (OR [odds ratio] = 1.6 [95% CI: 1.2, 2.2], P < 0.008). For countries with low and seasonal malaria transmission, such information can help programs design improved strategic interventions.     

Differential perpetuation of malaria species among Amazonian Yanomami Amerindians.

To determine whether malaria perpetuates within isolated Amerindian villages in the Venezuelan Amazon, we surveyed malaria infection and disease among 1,311 Yanomami in three communities during a 16-month period. Plasmodium vivax was generally present in each of these small, isolated villages; asymptomatic infection was frequent, and clinical disease was most evident among children less than five years of age (odds ratio [OR] = 6.3, 95% confidence interval [CI] = 1.4-29.2) and among persons experiencing parasitemias > or = 1,000 parasites/mm3 of blood (OR = 45.0, 95% CI = 5.5-370.7). Plasmodium falciparum, in contrast, was less prevalent, except during an abrupt outbreak in which 72 infections resulted in symptoms in all age groups and at all levels of parasitemia, and occasionally were life-threatening. The observed endemic pattern of P. vivax infection may derive from the capacity of this pathogen to relapse, while the epidemic pattern of P. falciparum infection may reflect occasional introductions of strains carried by immigrants or residents of distant villages and the subsequent disappearance of this non-relapsing pathogen.     

Predictive factors of malaria in travelers to areas where malaria is endemic

BACKGROUND: The differentiation of malaria from other causes of fever is difficult. The development of tools for rapid and specific clinical diagnosis is of paramount importance for the identification of individuals infected with malaria. METHOD: A 4-year prospective study to identify the clinical and biological variables associated with malaria included all patients suspected of having malaria who presented in the emergency department (ED) of a French hospital. RESULTS: Of 783 patients admitted to the ED with suspected malaria, 145 had positive findings of a thick smear for Plasmodium species, mainly Plasmodium falciparum (90.3%). In univariate analysis, the following 12 variables were significantly associated with diagnosis of malaria: older than 30 years, male sex, immigration to France from an area where malaria is endemic, a visit to sub-Saharan Africa, insufficient antimalaria prophylaxis, fever, chills, absence of diarrhea, a leukocyte count within the reference range, thrombocytopenia, and increased lactate dehydrogenase and bilirubin levels. In multivariate analysis, the factors predictive of malaria included a visit to sub-Saharan Africa (odds ratio [OR], 7.7; 95% confidence interval [CI], 2.8-21.3), a temperature of at least 38.5 degrees C (OR, 6.2; 95% CI, 2.8-13.3), chills (OR, 3.0; 95% CI, 1.4-6.6), thrombocytopenia (OR, 16.5; 95% CI, 7.1-38.3), and abnormally high total bilirubin levels (OR, 21.5; 95% CI, 6.4-72.5). However, alone or combined, these features had insufficient sensitivity (95.0%) and low specificity (55.0%) for the diagnosis of malaria. CONCLUSIONS: Malaria should be suspected in all patients presenting with complaints after travel to an area where malaria is endemic, and these patients should undergo blood microscopy.     

Factors contributing to anemia after uncomplicated falciparum malaria.

The factors contributing to anemia in falciparum malaria were characterized in 4,007 prospectively studied patients on the western border of Thailand. Of these, 727 patients (18%) presented with anemia (haematocrit < 30%), and 1% (55 of 5,253) required blood transfusion. The following were found to be independent risk factors for anemia at admission: age < 5 years, a palpable spleen, a palpable liver, recrudescent infections, being female, a prolonged history of illness (> 2 days) before admission, and pure Plasmodium falciparum infections rather than mixed P. falciparum and Plasmodium vivax infections. The mean maximum fractional fall in hematocrit after antimalarial treatment was 14.1% of the baseline value (95% confidence interval [CI], 13.6-14.6). This reduction was significantly greater in young children (aged < 5 years) and in patients with a prolonged illness, high parasitemia, or delayed parasite clearance. Loss of parasitized erythrocytes accounted for < 10% of overall red blood cell loss. Hematological recovery was usually complete within 6 weeks, but it was slower in patients who were anemic at admission (adjusted hazards ratio [AHR], 1.9, 95% CI, 1.5-2.3), and those whose infections recrudesced (AHR, 1.2, 95% CI, 1.01-1.5). Half the patients with treatment failure were anemic at 6 weeks compared with 19% of successfully treated patients (relative risk, 2.8, 95% CI, 2.0-3.8). Patients coinfected with P. vivax (16% of the total) were 1.8 (95% CI, 1.2-2.6) times less likely to become anemic and recovered 1.3 (95% CI, 1.0-1.5) times faster than those with P. falciparum only. Anemia is related to drug resistance and treatment failure in uncomplicated malaria. Children aged < 5 years of age were more likely than older children or adults to become anemic. Coinfection with P. vivax attenuates the anemia of falciparum malaria, presumably by modifying the severity of the infection.     

Malaria prophylaxis using azithromycin: a double-blind, placebo-controlled trial in Irian Jaya, Indonesia.

New drugs are needed for preventing drug-resistant Plasmodium falciparum malaria. The prophylactic efficacy of azithromycin against P. falciparum in malaria-immune Kenyans was 83%. We conducted a double-blind, placebo-controlled trial to determine the prophylactic efficacy of azithromycin against multidrug-resistant P. falciparum malaria and chloroquine-resistant Plasmodium vivax malaria in Indonesian adults with limited immunity. After radical cure therapy, 300 randomized subjects received azithromycin (148 subjects, 750-mg loading dose followed by 250 mg/d), placebo (77), or doxycycline (75, 100 mg/d). The end point was slide-proven parasitemia. There were 58 P. falciparum and 29 P. vivax prophylaxis failures over 20 weeks. Using incidence rates, the protective efficacy of azithromycin relative to placebo was 71.6% (95% confidence interval [CI], 50.3-83.8) against P. falciparum malaria and 98.9% (95% CI, 93.1-99.9) against P. vivax malaria. Corresponding figures for doxycycline were 96.3% (95% CI, 85.4-99.6) and 98% (95% CI, 88.0-99.9), respectively. Daily azithromycin offered excellent protection against P. vivax malaria but modest protection against P. falciparum malaria.     

Predictors of chloroquine treatment failure in children and adults with falciparum malaria in Kampala, Uganda

Chloroquine-resistant falciparum malaria is a serious problem in much of sub-Saharan Africa. However, it is desirable to continue to use chloroquine as first-line therapy for uncomplicated malaria where it remains clinically effective. To identify predictors of chloroquine treatment failure, a 14-day clinical study of chloroquine resistance in patients with uncomplicated falciparum malaria was performed in Kampala, Uganda. Among the 258 patients (88% follow-up), 47% were clinical failures (early or late treatment failure) and 70% had parasitological resistance (RI-RIII). Using multivariate analysis, an age less than five (odds ratio [OR] = 3.4, 95% CI = 1.8-6.3) and a presenting temperature over 38.0 degreesC (OR = 2.0, 95% CI = 1.1-3.7) were independent predictors of treatment failure. In addition, patients who last took chloroquine 3 to 14 days prior to study entry were significantly more likely to be treatment failures compared to patients with very recent (less than 3 days) or no recent chloroquine use. In areas with significant chloroquine resistance, easily identifiable predictors of chloroquine treatment failure might be used to stratify patients into those for whom chloroquine use is acceptable and those for whom alternative treatment should be used.     

Malaria: a 10-year (1994-2003) retrospective study at University Malaya Medical Center (UMMC), Kuala Lumpur, Malaysia

Malaria is still one of the most important vector-borne diseases in Malaysia, particularly in remote areas. This retrospective study was carried out to find the prevalence of malaria among patients admitted to UMMC Kuala Lumpur, from 1994-2003. A total of 86 malaria cases were analyzed. Most cases occurred among foreigners [57% (49 cases)] while Malaysians constituted 43% (37 cases). Among foreigners, Indonesians constituted the most [57% (28 cases)]. Among Malaysians, most cases occurred among the Chinese [35% (13 cases)] followed by the Malays [30% (11 cases)]. Males [70%(60 cases)] were more commonly affected. The majority of cases were within the 20-39 year age group (69%). Three species of malaria parasites were reported, of which Plasmodium vivax constituted the most [55%( 47 cases)], followed by Plasmodium falciparum [29% (25 cases)], and only four cases (5%) of Plasmodium malariae. Nine percent (8 cases) were mixed infections. In this study, 12%(10 cases) developed chloroquine resistance: 7 cases of P. falciparum, and 3 cases of P. vivax. The most common complications were jaundice and anemia [77% (23 cases)], followed by blackwater fever [13% (4 cases)] and cerebral malaria [10% (3 cases)]. Most of the complications were due to P. falciparum [43% (13 cases)]. There were no reported deaths. This new source of malaria coming from foreigners must be given serious attention, as it has great potential of increasing malaria cases in urban Malaysia.     

Chloroquine/doxycycline combination versus chloroquine alone, and doxycycline alone for the treatment of Plasmodium falciparum and Plasmodium vivax malaria in northeastern Irian Jaya, Indonesia.

Combination therapy is one method of overcoming the global challenge of drug-resistant Plasmodium falciparum malaria. We conducted a hospital-based 28-day in vivo test comparing chloroquine/doxycycline to chloroquine or doxycycline alone for treating P. falciparum and Plasmodium vivax malaria in Irian Jaya, Indonesia. Eighty-nine patients with uncomplicated falciparum malaria were randomized to standard dose chloroquine (n = 30), doxycycline (100 mg every 12 hours [7 days], n = 20), or chloroquine with doxycycline (n = 39); corresponding numbers for vivax malaria (n = 63) were 23, 16, 24. Endpoints were parasite sensitivity (S) or resistance (RI/RII/RIII). Of the 105 evaluable patients, chloroquine/doxycycline cured (S) 20/22 (90.9% [95% CI 78.9-100%]) patients with P. falciparum malaria; 2/22 (9.1% [0-21%]) were RIII resistant. Doxycycline cured 11/17 (64.7% [42.0-87.4%]) patients, and chloroquine 4/20 (20% [2.5-37.5%]). Against P. vivax, chloroquine/doxycycline cured (S) 12/17 (70.6% [48.9-92.2%]) patients, doxycycline 4/12 (33.3% [6.6-59.9%]), and chloroquine 5/17 (29.4% [7.7-51.1%]). Chloroquine/doxycycline was effective against P. falciparum but only modestly effective against P. vivax. These findings support the use of chloroquine/doxycycline as an inexpensive alternative to mefloquine for treating chloroquine-resistant P. falciparum but not chloroquine-resistant P. vivax in this setting.     

Risk Factors for Border Malaria in a Malaria Elimination Setting: A Retrospective Case-Control Study in Yunnan,China

A retrospective case-control study was conducted to identify risk factors for border malaria in a malaria elimination setting of Yunnan Province, China. The study comprised 214 cases and 428 controls. The controls were individually matched to the cases on the basis of residence, age, and gender. In addition, statistical associations are based on matched analyses. The frequencies of imported, male, adult, and vivax malaria cases were respectively 201 (93.9%), 194 (90.7%), 210 (98.1%), and 176 (82.2%). Overnight stay in Myanmar within the prior month was independently associated with malaria infection (odds ratio [OR] 159.5, 95% confidence interval [CI] 75.1–338.9). In particular, stays in lowland and foothill (OR 5.5, 95% CI 2.5–11.8) or mid-hill (OR 42.8, 95% CI 5.1–319.8) areas, or near streamlets (OR 15.3, 95% CI 4.3–55.2) or paddy field or pools (OR10.1, 95% CI 4.4–55.8) were found to be independently associated with malaria. Neither forest exposure nor use of vector control measures was associated with malaria. In conclusion, travel to lowland and foothill or mid-hill hyperendemic areas, especially along the waterside in Myanmar, was found to be the highest risk factor for malaria. In considering the limitations of the study, further investigations are needed to identify the major determinants of malaria risk and develop new strategies for malaria elimination on China-Myanmar border.     

The International Health Program: the fifteen-year experience with Yale University's Internal Medicine Residency Program

The factors affecting the development of patent Plasmodium falciparum gametocytemia were assessed in 5,682 patients entered prospectively into a series of antimalarial drug trials conducted in an area of low and seasonal transmission on the western border of Thailand. Of the 4,565 patients with admission thick smear assessments, 110 (2.4%) had gametocytemia. During the follow-up period 170 (3%) of all patients developed patent gametocytemia, which in 89% had developed by day 14 following treatment. In a multiple logistic regression model five factors were found to be independent risk factors at presentation for the development or persistence of gametocytemia during follow up; patent gametocytemia on admission (adjusted odds ratio [AOR] = 7.8, 95% confidence interval [CI] = 3.7-16, P < 0.001), anemia (hematocrit <30%) (AOR = 3.9, 95% CI = 2.3-6.5, P < 0.001), no coincident P. vivax malaria (AOR = 3.5, 95% CI = 1.04-11.5, P < 0.04), presentation with a recrudescent infection (AOR = 2.3, 95% CI = 1.3-4.1, P < 0.004), and a history of illness longer than two days (AOR = 3.3, 95% CI = 1.7-6.6, P < 0.001). Patients whose infections responded slowly to treatment or recrudesced subsequently were also more likely to carry gametocytes than those who responded rapidly or were cured (relative risks = 1.9, 95% CI = 1.3-2.7 and 2.8, 95% CI = 2.0-4.0, respectively; P < 0.001). These data provide further evidence of important epidemiologic interactions between P. falciparum and P. vivax, and drug resistance and transmission potential.     

Rapid diagnostic devices for malaria: field evaluation of a new prototype immunochromatographic assay for the detection of Plasmodium falciparum and non-falciparum Plasmodium

The NOW ICT Malaria P.f./P.v. for Whole Blood (Binax, Inc., Portland, ME) is a new malaria rapid diagnostic device that represents a technical advance over previous assays, such as ICT Malaria P.f./P.v. and ICT Malaria P.f.. We evaluated this device in March 2001 in symptomatic patients at malaria clinics in Maesod, Thailand. Microscopic examination of Giemsa-stained blood smears was the reference standard. In 246 patients, microscopy showed 32 (13.0%) infected with Plasmodium falciparum, 63 (25.6%) with P. vivax, 6 (2.4%) with mixed infections of P. falciparum and P. vivax, 5 (2.0%) with P. malariae, and 140 (56.9%) negative. Sensitivity for P. falciparum was 100% and specificity was 96.2% (200 of 208; 95% confidence interval [CI] = 92-98). For P. vivax, sensitivity was 87.3% (55 of 63; 95% CI = 77-93) and specificity was 97.7% (173 of 177; 95% CI = 95-99), but all the four false-positive results were microscopically positive for P. malariae; thus, specificity for non-falciparum Plasmodium was 100%. These results suggest improved performance over NOW ICT predecessors.     

Assessing the Parasight-F test in northeastern Papua,Indonesia, an area of mixed Plasmodium falciparum and Plasmodium vivax transmission

User-friendly, reliable, and inexpensive methods for diagnosing malaria are needed at the primary health care level. During a randomized treatment trial, the Parasight-F test was assessed on days 0, 3, 7, and 28 against standard light microscopy of Giemsa-stained thick blood smears for diagnosing Plasmodium falciparum parasitemia in patients with P. falciparum (n = 84) or P. vivax (n = 59) malaria. The median P. falciparum parasite count on day 0 was 2,373/microL (range = 20-74,432/microL). At the start of treatment, the Parasight-F test had a sensitivity of 95.2% (80 of 84; 95% confidence interval [CI] = 88.2-98.7), and a specificity of 94.9% (56 of 59; 95% CI = 85.8-98.9). On day 7, this test showed false-positive results in 17 (16.3%) of 104 patients (95% CI = 9.8-24.9). The Parasight-F test performed well when compared with light microscopy in detecting P. falciparum parasitemia in patients presenting with clinical malaria. However, the high false-positive rate on day 7 limits its use for patient follow-up.     

Comparison of three antigen detection methods for diagnosis and therapeutic monitoring of malaria: a field study from southern Vietnam

OBJECTIVES: To compare the sensitivity, specificity and post-treatment persistence of three commonly used rapid antigen detection methods. METHOD: We studied 252 Vietnamese patients aged from 4 to 60 years, 157 with falciparum and 95 with vivax malaria and 160 healthy volunteers. An initial blood sample was taken for microscopy, and OptiMAL, immunochromatographic test (ICT) malaria P.f./P.v. and Paracheck-Pf tests. Patients with falciparum malaria were treated with an artesunate-based combination regimen and those with vivax malaria received chloroquine. Eighty-seven patients with falciparum malaria who were initially positive for one of the antigen tests and who remained blood smear-negative underwent follow-up testing over 28 days. RESULTS: Paracheck-Pf was the most sensitive test for Plasmodium falciparum (95.8% vs. 82.6% for ICT malaria P.f./P.v. and 49.7% for OptiMAL). Specificities were all 100%. For vivax malaria, OptiMAL performed better than ICT malaria P.f./P.v. (sensitivities 73.7% and 20.0%, respectively), with 100% specificity in both cases. All tests had low sensitivities (< or = 75.0%) at parasitaemias < 1000/microl regardless of malaria species. During follow-up, Paracheck-Pf remained positive in the greatest proportion of patients, especially at higher parasitaemias (> 10,000/microl). Residual OptiMAL positivity occurred only in a relatively small proportion of patients (< 10%) with parasitaemias > 10,000/microl during the first 2 weeks after treatment. CONCLUSIONS: Although microscopy remains the gold standard for malaria diagnosis, Paracheck-Pf may prove a useful adjunctive test in uncomplicated falciparum malaria in southern Vietnam. OptiMAL had the lowest sensitivity for P. falciparum but it might have a use in the diagnosis of vivax malaria and perhaps to monitor efficacy of treatment for falciparum malaria where microscopy is unavailable.     

Thrombocytopenia in childhood malaria with special reference to P. vivax monoinfection: A study from Bikaner (Northwestern India)

Thrombocytopenia is commonly seen in Plasmodium vivax malaria, but its prognostic value has not been addressed in children. This prospective study included 676 admitted children of malaria [Plasmodium falciparum (Pf) monoinfection 262, Plasmodium vivax (Pv) monoinfection 380, and mixed (Pf?+?Pv) infection 34], in which thrombocytopenia (platelet count <150?×?10(3)/mm(3) on admission) was found in 442 (65.38%) children [Pf monoinfection 55.3% (145/262), Pv monoinfection 73.16% (278/380), and mixed infection 55.88% (19/34)]. The association of thrombocytopenia was statistically significant with Pv monoinfection [73.16% (278/380)] in comparison to either Pf monoinfection [55.34% (145/262); odds ratio (OR)?=?2.199 (95% confidence interval (CI) 1.577-3.068), p?相似文献