Prevalence Of Asymptomatic Malaria Parasitaemia Research Articles

Asymptomatic Plasmodium falciparum and HBV coinfections among inmates at Owo Correctional Facility, Nigeria

BackgroundMalaria and hepatitis B are significant public health infections in Nigeria. Coinfection with both pathogens is common where both diseases are endemic. Epidemiological surveys are essential for determining the burden of diseases and possible coinfection with multiple pathogens in vulnerable populations. There has been a lack of reports on HBV/malaria coinfection, particularly among marginalized groups in Ondo State. Thus, we used malaria microscopy and the HBsAg serological test to examine the prevalence of asymptomatic malaria parasitemia and HBV infections respectively among inmates at the Nigerian Correctional Center in Owo, Ondo State, Nigeria.ResultsOut of the 126 prisoners and staff members who were evaluated, 20.6% and 7.9% tested positive for malaria and HBV infections, respectively. It was discovered that 1.6% of the individuals were coinfected with malaria and HBV. Plasmodium falciparum was the only malaria species recovered in malaria-infected individuals. Except for HBV, where gender was found to differ considerably with the proportion of HBV infection, variations in single infections with either pathogen did not vary with demographic characteristics.ConclusionWe suggest that the prison system should be considered in healthcare programs to improve the health of inmates.

Prevalence of Asymptomatic Malaria Parasitemia among Blood Donors in Cape Coast, Ghana: A Cross-Sectional Study.

Malaria is an important transfusion-associated infection in many parts of the world, particularly in sub-Saharan Africa, where it is endemic. We studied the prevalence of malaria parasites among blood donors in the Cape Coast Metropolitan Area. A malaria parasite examination was added to the blood donor screening protocol for 240 voluntary and replacement blood donors (224 males and 16 females) between December 2020 and July 2021. Overall, 2.5% (6/240) had Plasmodium falciparum trophozoites detected in their blood sample. The remaining had no parasites detected. Four of the 148 who passed the blood donor screening tests were infected. The remaining two with malaria parasites failed one screening test. These included one donor with "hepatitis B + P. falciparum" and another with "syphilis + P. falciparum" parasite coinfection. All blood donors who had malaria parasites detected in their blood were males. Most donors, 45.8% (110/240), were in the 26-35 age group, with the highest prevalence of 1.3% (3/240). Blood group O was predominant (75.0%, 180/240), followed by B (12.9%, 31/240), A (11.3%, 27/240), and AB (0.8%, 2/240). All malaria parasites detected were among individuals with blood group O. Moreover, 96.3% (231/240) were rhesus-positive and had the highest prevalence of 2.1% (5/240). Screening of blood donors in Ghana does not include malaria, although there is the potential for transmission through blood products. Malaria transmission via blood transfusion remains an issue of public health concern, as indicated in the results of this current study. We recommend studies on malaria prevention, pretransfusion and posttransfusion, and pathogen reduction technology.

Attributable risk factors for asymptomatic malaria and anaemia and their association with cognitive and psychomotor functions in schoolchildren of north-eastern Tanzania.

In Africa, children aged 5 to 15 years (school age) comprises more than 50% (>339 million) of the under 19 years population, and are highly burdened by malaria and anaemia that impair cognitive development. For the prospects of improving health in African citizens, understanding malaria and its relation to anaemia in school-aged children, it is crucial to inform targeted interventions for malaria control and accelerate elimination efforts as part of improved school health policy. We conducted a study to determine the risk factors for asymptomatic malaria and their association to anaemia. We explored the prevalence of antimalarial drug resistance as well as the association of asymptomatic malaria infection and anaemia on cognitive and psychomotor functions in school-aged children living in high endemic areas. This study was a comprehensive baseline survey, within the scope of a randomised, controlled trial on the effectiveness and safety of antimalarial drugs in preventing malaria and its related morbidity in schoolchildren. We enrolled 1,587 schoolchildren from 7 primary schools located in Muheza, north-eastern Tanzania. Finger-pricked blood samples were collected for estimation of malaria parasitaemia using a microscope, haemoglobin concentration using a haemoglobinometer, and markers of drug resistance processed from dried blood spots (DBS). Psychomotor and Cognitive functions were assessed using a ‘20 metre Shuttle run’ and a test of everyday attention for children (TEA-Ch), respectively. The prevalence of asymptomatic malaria parasitaemia, anaemia and stunting was 26.4%, 49.8%, and 21.0%, respectively with marked variation across schools. In multivariate models, asymptomatic malaria parasitaemia attributed to 61% of anaemia with a respective population attribution fraction of 16%. Stunting, not sleeping under a bednet and illiterate parent or guardian were other factors attributing to 7%, 9%, and 5% of anaemia in the study population, respectively. Factors such as age group (10–15 years), not sleeping under a bednet, low socioeconomic status, parents’ or guardians’ with a low level of education, children overcrowding in a household, and fewer rooms in a household were significantly attributed to higher malaria infection. There was no significant association between malaria infection or anaemia and performance on tests of cognitive function (sustained attention) or psychomotor function (VO2 max). However, a history of malaria in the past one month was significantly associated with decreased cognitive scores (aOR = -4.1, 95% CI -7.7–0.6, p = 0.02). Furthermore, stunted children had significantly lower VO2max scores (aOR = -1.9, 95% CI -3.0–0.8, p = 0.001). Regarding the antimalarial drug resistance markers, the most prevalent Pfmdr1 86-184-1034-1042-1246 haplotypes were the NFSND in 47% (n = 88) and the NYSND in 52% (n = 98). The wild type Pfcrt haplotypes (codons 72–76, CVMNK) were found in 99.1% (n = 219) of the samples. Malaria, stunting and parents’ or guardians’ illiteracy were the key attributable factors for anaemia in schoolchildren. Given malaria infection in schoolchildren is mostly asymptomatic; an addition of interventional programmes such as intermittent preventive treatment of malaria in schoolchildren (IPTsc) would probably act as a potential solution while calling for an improvement in the current tools such as bednet use, school food programme, and community-based (customised) health education with an emphasis on nutrition and malaria control.

The Rate of Asymptomatic Plasmodium Parasitemia and Placental Parasitization in Urban and Rural Areas of Cross River State, Nigeria

Background: Malaria in pregnancy contributes to feto-maternal morbidity and mortality even in asymptomatic forms of the disease especially in malaria endemic regions such as Nigeria. Objective: To determine the rate of asymptomatic malaria parasitemia and placental parasitization among the rural and urban pregnant women and its feto-maternal effects in Cross River State, Nigeria. Methodology: This was a prospective study of 440 pregnant women in rural and urban settings. Participants completed structured questionnaire and also have their blood samples and placentas examined for presence of malaria parasites by microscopy and histology respectively. Maternal hemoglobin concentration, birth weight, neonatal length, Apgar score and other anthropometric measurements were obtained to assess feto-maternal effect of asymptomatic malaria parasitemia and placental parasitisation in pregnancy. Data were analyzed using SPSS version 21.0 and level of significance was set as 0.05. ResultsThe prevalence of asymptomatic malaria parasitemia was 40.2% while malaria placental parasitization was 70.2%. Based on residential status, 49.5% of rural residents had malaria parasitemia which is significantly higher than their urban resident counterparts 30.9% (p=0.000). The prevalence of placental parasitization was significantly higher among rural residents 80.9% than their urban resident counterparts 59.5% (p=0.000). Concerning obstetric outcome of patients with positive malaria placental parasitisation, preterm delivery, low 5th minutes Apgar score (<7), low birth weight (<2.5kg) and low neonatal length were significantly higher in pregnancy with positive placental parasitisation than in women with negative placental malaria parasitisation. Also, preterm delivery, anemia, low 5th minutes Apgar score (<7) and low birth weight (<2.5kg) were significantly higher in pregnancy with positive malaria parasitemia than women with negative malaria parasitemia. ConclusionAsymptomatic malaria parasitemia (40.2%) and malaria placental parasitization (70.2%) in this study is high and contributes to poor obstetric outcomes mostly in the rural areas. Rural pregnant women have the highest burden than the urban women. Promotion of the use of ITNs, IPT during pregnancy and other malaria preventive measures are necessary especially in rural areas where malaria burden is highest.

High Prevalence of Asymptomatic Malarial Anemia and Association with Early Conversion from Asymptomatic to Symptomatic Infection in a Plasmodium falciparum Hyperendemic Setting in Cameroon.

Asymptomatic malarial parasitemia is highly prevalent in Plasmodium falciparum endemic areas and often associated with increased prevalence of mild to moderate anemia. The aim of this study was to assess the prevalence of anemia during asymptomatic malaria parasitemia and its interplay with persistent infection in highly exposed individuals. A household-based longitudinal survey was undertaken in a malaria hyperendemic area in Cameroon using multiplex nested polymerase chain reaction to detect plasmodial infections. Residents with P. falciparum asymptomatic parasitemia were monitored over a 3-week period with the aid of structured questionnaires and weekly measurements of axillary temperatures. Of the 353 individuals included (median age: 26 years, range 2-86 years, male/female sex ratio 0.9), 328 (92.9%) were positive for malaria parasitemia of whom 266 (81.1%) were asymptomatic carriers. The prevalence of anemia in the study population was 38.6%, of which 69.2% were asymptomatic. Multivariate analyses identified high parasitemia (> 327 parasites/µL) and female gender as associated risk factors of asymptomatic malarial anemia in the population. Furthermore, risk analyses revealed female gender and anemia at the time of enrolment as key predictors of early development of febrile illness (< 3 weeks post enrolment) among the asymptomatic individuals. Together, the data reveal an extremely high prevalence of asymptomatic malaria parasitemia and anemia in the study area, unveiling for the first time the association of asymptomatic malarial anemia with early clinical conversion from asymptomatic to symptomatic infection. Furthermore, these findings underscore the negative impact of asymptomatic malaria parasitemia on individual health, necessitating the development of appropriate control and preventive measures.

Prevalence of Asymptomatic Malaria Parasitemia in Odisha, India: A Challenge to Malaria Elimination.

The prevalence of malaria in India is decreasing, but it remains a major concern for public health administration. The role of submicroscopic malaria and asymptomatic malaria parasitemia and their persistence is being explored. A cross-sectional survey was conducted in the Kandhamal district of Odisha (India) during May-June 2017. Blood samples were collected from 1897 individuals for screening of asymptomatic parasitemia. Samples were screened using rapid diagnostic tests (RDTs) and examined microscopically for Plasmodium species. Approximately 30% of randomly selected samples (n = 586) were analyzed using real-time PCR (qPCR), and the genetic diversity of Plasmodium falciparum was analyzed. The prevalence of Plasmodium species among asymptomatic individuals detected using qPCR was 18%, which was significantly higher than that detected by microscopy examination (5.5%) or RDT (7.3%). Of these, 37% had submicroscopic malaria. The species-specific prevalence among asymptomatic malaria-positive cases for P. falciparum, Plasmodium vivax, and mixed infection (P. falciparum and P. vivax) by qPCR was 57%, 29%, and 14%, respectively. The multiplicity of infection was 1.6 and 1.2 for the merozoite surface protein-1 gene (msp1) and (msp2), respectively. Expected heterozygosity was 0.64 and 0.47 for msp1 and msp2, respectively. A significant proportion of the study population, 105/586 (18%), was found to be a reservoir for malaria infection, and identification of this group will help in the development of elimination strategies.

Prevalence of asymptomatic malaria parasitaemia following mass testing and treatment in Pakro sub-district of Ghana

BackgroundGlobal efforts to scale-up malaria control interventions are gaining steam. These include the use of Long-Lasting Insecticide Nets, Indoor Residual Spraying, Intermittent Preventive Treatment and Test, Treat and Track. Despite these, the drive for malaria elimination is far from being realistic in endemic communities in Africa. This is partly due to the fact that asymptomatic parasite carriage, not specifically targeted by most interventions, remains the bedrock that fuels transmission. This has led to mass testing, treatment and tracking (MTTT) as an alternative strategy to target asymptomatic individuals. We report the impact of MTTT on the prevalence of asymptomatic malaria parasitaemia over a one-year period in Ghana, hypothesizing that implementing MTTT could reduce the rate of asymptomatic parasitaemia.MethodsA population of about 5000 individuals in seven communities in the Pakro sub-district of Ghana participated in this study. A register was developed for each community following a census. MTTT engaged trained community-based health volunteers who conducted house-to-house testing using RDTs every 4 months and treated positive cases with Artemisinin–based Combination Therapy. Between interventions, community-based management of malaria was implemented for symptomatic cases.ResultsMTTT Coverage was 98.8% in July 2017 and 79.3% in July 2018. Of those tested, asymptomatic infection with malaria parasites reduced from 36.3% (1795/4941) in July 2017 to 32.9% (1303/3966) in July 2018 (p = 0.001). Prevalence of asymptomatic parasitaemia among children under 15 years declined from 52.6% (1043/1984) in July 2017 to 47.5% (820/1728) in July 2018 (p = 0.002). Implementing MTTT significantly reduced asymptomatic parasitaemia by 24% from July 2017 to July 2018 after adjusting for age, ITN use and axillary temperature (OR = 0.76, CI = 0.67, 0.85 p ≤ 0.001).ConclusionThis study has demonstrated that implementing MTTT is feasible and could reduce the prevalence of asymptomatic malaria parasitaemia in children under 15 years of age. Furthermore, the use of community-based health volunteers could ensure high coverage at lower cost of implementation.Trial registrationNCT04167566, Date 14/11/2019. Retrospective registration.

The prevalence of asymptomatic malaria parasitemia and associated factors among adults in Dembia district, northwest Ethiopia, 2017

BackgroundMalaria is still a leading cause of morbidity and mortality in many developing countries including Ethiopia. Its prevalence has been declining among Ethiopian adults, especially in Dembia district. However, it is still at the top of diseases list at the district. Hence, the study aimed to determine the prevalence and the factors that contribute to its being the major public health concern despite different preventive and control measures in place.MethodsA community based cross-sectional study was conducted from October 11 to November 16, 2017. The multistage sampling technique was employed to select 832 study participants. A rapid diagnostic test were used to confirm the disease. Data were entered using Epi info version 7 and was analyzed by Statistical Package for Social Science (SPSS) version 20. The logistic regression model was performed to examine the association of factors with malaria parasite.ResultsOut of the 832 adults included in the study, 6.7% (95% Confidence Interval (CI: 5.2–8.7)) were confirmed to be malaria parasite carriers. The dominant plasmodium species was Plasmodium falciparum [46 (82%)]. According to the multivariable logistic regression analysis, male sex (Adjusted Odds Ratio (AOR = 4.5; 95%CI: 2.1–9.5), adult age 15–19 years (AOR = 4.5; 95%CI: 2.1–9.7), travel history (AOR = 5; 95%CI: 2.34–12.25), and stagnant water around home (AOR = 3.7; 95%CI: 1.57–8.87) increased the probability of malaria infectivity, while Insecticidal Treated Nets (ITN) utilization (AOR = 0.2; 95%CI: 0.09–0.31) decreased it.ConclusionMalaria is still an important public health challenge among adults in the study area. Male sex, age 15–19 years, travel history, living around stagnant water, and not using ITN increased the probability of infection. Therefore, the District Health office and Health extension workers should work to increase ITN distribution and focus on reducing malaria breading sites through community participation.

Long-lasting insecticidal net use and asymptomatic malaria parasitaemia among household members of laboratory-confirmed malaria patients attending selected health facilities in Abuja, Nigeria, 2016: A cross-sectional survey.

IntroductionIn Nigeria, malaria remains a major burden. There is the presupposition that household members could have common exposure to malaria parasite and use of long-lasting insecticidal net (LLIN) could reduce transmission. This study was conducted to identify factors associated with asymptomatic malaria parasitaemia and LLIN use among households of confirmed malaria patients in Abuja, Nigeria.MethodsA cross-sectional survey was conducted from March to August 2016 in twelve health facilities selected from three area councils in Abuja, Nigeria. Participants were selected using multi-stage sampling technique. Overall, we recruited 602 participants from 107 households linked to 107 malaria patients attending the health facilities. Data on LLIN ownership, utilization, and house characteristics were collected using a semi-structured questionnaire. Blood samples of household members were examined for malaria parasitaemia using microscopy. Data were analyzed using descriptive statistics, Chi-square, and logistic regression (α = 0.05).ResultsMedian age of respondents was 16.5 years (Interquartile range: 23 years); 55.0% were females. Proportions of households that owned and used at least one LLIN were 44.8% and 33.6%, respectively. Parasitaemia was detected in at least one family member of 102 (95.3%) index malaria patients. Prevalence of asymptomatic malaria parasitaemia among study participants was 421/602 (69.9%). No association was found between individual LLIN use and malaria parasitaemia (odds ratio: 0.9, 95% confidence interval (95%CI): 0.6–1.3) among study participants. Having bushes around the homes was associated with having malaria parasitaemia (adjusted OR (aOR): 2.7, 95%CI: 1.7–4.2) and less use of LLIN (aOR: 0.4, 95%CI: 0.2–0.9). Living in Kwali (aOR: 0.1, 95% CI: 0.0–0.2) was associated with less use of LLIN.ConclusionHigh prevalence of asymptomatic malaria and low use of LLIN among household members of malaria patients portend the risk of intra-household common source of malaria transmission. We recommend household health education on LLIN use and environmental management. Study to explore the role of preventive treatment of household members of confirmed malaria patient in curbing transmission is suggested. Strategies promoting LLIN use need to be intensified in Kwali.

Anemia associated with asymptomatic malaria among pregnant women in the rural surroundings of Arba Minch Town, South Ethiopia.

BackgroundAnemia during pregnancy is a well known medical condition most of the time under-recognized as it is overshadowed by the normal physiological condition during pregnancy. This study aimed at determining the prevalence and predictors of anemia among pregnant women residing in the rural surroundings of Arbaminch Town, south Ethiopia.MethodsA cross-sectional community based study was conducted between April and June, 2013. A structured questionnaire was used to collect socio-economic and socio-demographic characteristics of the pregnant women. Hematocrit (HCT) level was determined to classify the pregnant women as anemic and non-anemic. Diagnosis of asymptomatic malaria parasitemia was done by Giemsa stained blood smear microscopy. HCT < 33%, (HCT ≥ 30% & < 33%), (HCT ≥ 21% & < 30%), and HCT < 21% was used to indicate anemia, mild anemia, moderate anemia, and severe anemia respectively.ResultsA total of 341 pregnant women participated in this study, out of which 118 (34.6%) were anemic. The median age of the pregnant women was 25 years (Inter-quartile range: 23–29). The mean HCT was 35.2% (95% CI: 34.6%–35.8%) with SD of ±5.5%. Of those 118 anemic women; 73(61.9%) were mildly anemic, 38(32.2%) were moderately anemic, and 7(5.9%) were found to be severely anemic. The prevalence of asymptomatic malaria parasitemia was 9.1% (31/341). The odds of being anemic were 15.72 times [AOR: 15.72, 95% CI (3.97, 62.22), P-value ≤ 0.001] more likely to occur in parasitemic individuals relative to the non parasitemic pregnant women. Not using insecticide treated bed net (ITN) was a significant predictor of anemia among the pregnant women [AOR: 3, 95% CI: (1.72, 5.22), P < 0.001].ConclusionThis study highlighted the significant association between anemia and asymptomatic malaria among pregnant women in the study area. Therefore, the practice of routine screening for malaria and anemia followed by prompt management should be encouraged to curb the effect of malaria and anemia on the pregnant women as well as her fetus. Further studies should also be in place to test the effectiveness of routine screening for malaria and anemia followed by prompt management.

Effect of HIV-1 Serostatus on the Prevalence of Asymptomatic Plasmodium falciparum Parasitemia Among Children Less Than 5 Years of Age in Benin City, Nigeria.

Human immunodeficiency virus (HIV) infection and Plasmodium falciparum malaria are 2 of the gravest health threats in sub-Saharan Africa. Multiple repeat infections with the malaria parasite as seen in endemic areas are necessary to develop specific malaria immunity. HIV is an immunosuppressive virus and in children aged <5 years, development of malaria-specific immunity may be impaired and malaria parasite clearance in theory will be delayed; hence the predisposition to increased incidence of asymptomatic malaria or severe malaria. This cross-sectional study was carried out to examine associations between immunosuppression and asymptomatic malaria parasitemia (ASMP) in HIV-infected children aged <5 years in Benin City. One hundred seventy-nine asymptomatic HIV-1-positive and 179 age- and sex-matched HIV-1-negative children aged <5 years were recruited. The malaria parasite was determined by Giemsa-stained blood film by certified microscopy while concomitant CD4(+) count was estimated in the HIV-infected children. The prevalence of ASMP in those who were HIV-infected of 34.1% was significantly higher than 17.3% in the HIV uninfected (P = .001). The prevalence of ASMP was highest (59.3%) among subjects who were severely immunosuppressed (CDC immunologic category 3). The prevalence of ASMP significantly increased with advanced immune disease in the subjects (P = .011). Severe (World Health Organization) clinical staging was also significantly associated with increased prevalence of ASMP (P = .031). The prevalence of ASMP is significantly higher among subjects not receiving cotrimoxazole, associated with threefold risk of having ASMP (P = .003: odds ratio = 3.5). ASMP is more common in HIV-positive children aged <5 years and is significantly associated with declining CD4(+) T-cell count and severe clinical disease. There is a need for integration of HIV- and malaria-control programs for stronger case management. Malaria-control programs may consider malaria prevention interventions and cotrimoxazole prophylaxis for preschool children who are HIV-infected and living in malaria-endemic regions.

Prevalence and parasite density of asymptomatic malaria parasitemia among unbooked paturients at Abakaliki, Nigeria

Background: Malaria in pregnancy has contributed significantly to maternal morbidity and mortality in our environment. Aim: This study was aimed at determining the prevalence, and parasite density of asymptomatic malaria parasitemia among unbooked paturients at Federal Teaching Hospital Abakaliki. Subjects and Methods: This was a prospective cross‑sectional study conducted in the labor ward complex of the Federal Teaching Hospital Abakaliki over a period of three months from March to May 2012. Two hundred and fifty unbooked women presenting in labor at term and willing to participate were consecutively recruited. A structured data collection sheet was administered to each parturient. Thick and thin blood films were prepared for quantification and speciation of parasitemia respectively. Results: A total of 250 unbooked parturients participated in the study. The mean age of the parturients was 28.2 (7.2) years. One hundred and seven 107/250 (42.8%) were primigravid, 111/250 (44.4%) were between para 1‑4 while 32/250 (12.8%) were para 5 and above. Majority of the parturients 236/250 (95.2%) were of low socio‑economic class. The prevalence of asymptomatic malaria parasitemia was 77.6%. Asymptomatic malaria parasitemia was most prevalent among paturients of social class 5 (24/32 (75%) and primigravid paturients (93/107 (86.9%)) and the association of asymptomatic malaria parasitemia with parity (χ2 = 10.8, P = 0.01) and social class (χ2 = 10.88, P = 0.02) was statistically significant. Conclusion: There was high prevalence of asymptomatic malaria parasitemia in the study. Preconceptional care and early antenatal booking are advocated with emphasis on prevention of malaria infestation through health education and effective use of insecticide treated nets and intermittent prophylaxis therapy for malaria during pregnancy.

No asymptomatic malaria parasitaemia found among 108 young children at one health facility in Dar es Salaam, Tanzania

BackgroundAsymptomatic malaria parasitaemia has been reported in areas with high malaria transmission. It may serve as a reservoir for continued transmission, and furthermore complicates diagnostics, as not all individuals with a positive malaria test are necessarily ill due to malaria, although they may present with malaria-like symptoms. Asymptomatic malaria increases with age as immunity to malaria gradually develops. As mortality and morbidity of malaria is higher among younger children it is important to know the prevalence of asymptomatic malaria parasitaemia in this population in order to interpret laboratory results for malaria correctly.MethodsA total of 108 children that had neither been treated for malaria nor had a fever the previous four weeks were recruited consecutively at a maternal and child health clinic (MCHC) in Dar es Salaam, Tanzania. A rapid diagnostic test (RDT) for malaria and dried blood spot (DBS) on filter paper were taken from each child. Social and clinical data were recorded. DNA was extracted from the DBS of study participants by a method using InstaGene™ matrix. PCR targeting the Plasmodium mitochondrial genome was performed on all samples.ResultsMedian age was 4.6 months (range 0.5-38). All the RDTs were negative. PCR was negative for all study subjects.ConclusionThe study suggests that asymptomatic malaria may not be present in apparently healthy children up to the age of three years in Dar es Salaam, Tanzania. However, because of the small sample size and low median age of the study population, the findings cannot be generalized. Larger studies, including higher age groups, need to be done to clarify whether asymptomatic malaria parasitaemia is present in the general population in the Dar es Salaam area.

Asymptomatic malaria parasitaemia using rapid diagnostic test in unbooked pregnant women in rural Ondo-south district, Nigeria.

Malaria is a major contributor of maternal and peri-natal morbidity and mortality. The disease may be asymptomatic despite sequestration of parasitized red blood cells in the placental micro-circulation with antecedent complications. In such condition, it may also be difficult to identify the malaria parasite by the peripheral blood film microscopy, thus the need for use of simple but reliable tool for malaria parasite diagnosis. To determine the prevalence of asymptomatic malaria parasitaemia using the Rapid Diagnostic Test in pregnant unbooked women seen in a primary health centre during a malaria control campaign programme in rural Ondo-south, District Nigeria. Prevalence of asymptomatic malaria parasitaemia was 25.9%. Only 3 (3.5%) of the 85 women had the long lasting insecticide-treated nets. There was no significant association between malaria parasitaemia, and the age group, parity and gestation age. Given the high prevalence of asymptomatic malaria in pregnancy, routine screening for malaria at booking and scaling-up of other malaria control strategies such as the use of long lasting insecticidal-treated nets and intermittent preventive therapy for pregnant women are recommended.

The impact of intermittent preventive treatment with sulfadoxine-pyrimethamine on the prevalence of malaria parasitaemia in pregnancy

The Roll Back Malaria initiatives were introduced to ensure that 60% of pregnant women receive intermittent preventive anti-malarial treatment by the end of 2005 in an attempt to halve the mortality from malaria by 2010. Our aim was to determine the prevalence of asymptomatic malaria parasitaemia in pregnant women on intermittent preventive treatment (IPT) with sulfadoxine-pyrimethamine (SP) compared with a control group. This comparative study involved testing the peripheral blood of pregnant women on IPT with SP and a control group that did not receive SP for the malaria parasite upon registration and at 34 weeks gestational age. The levels of parasitaemia in the intervention group upon registration (4.9%) and at 34 weeks (63.9%) were not significantly different (P > 0.05) from that of the control group (10%) and at 34 weeks gestation (68.3%). IPT with SP during pregnancy did not significantly reduce the prevalence of the malaria parasitaemia among the pregnant women in our environment.

Prevalence of malaria parasitemia amongst asymptomatic pregnant women attending a Nigerian teaching hospital

Malaria parasitemia among pregnant women is associated with complications to mother and the unborn fetus. There is paucity of data on asymptomatic malaria parasitemia, particularly in the northwest region of Nigeria. The objectives of this study were to determine the prevalence of malaria parasitemia in asymptomatic pregnant women and to estimate the packed cell volume (PCV) of this group of pregnant women. This was a cross-sectional, descriptive study of only well pregnant women recruited consecutively at the time of booking for antenatal care. Thick film microscopy and qualitative immunoassay test for malaria parasite (MP) were performed for all the women. PCV estimation was also done using the micro-centrifuge method and comparison was made for women with parasitemia with those without MP. Some socio-demographic variables were also analyzed. Chi-square test was used to test for significance and a P-value less than 0.05 was considered statistically significant. Two hundred and twenty-five healthy pregnant women were studied. Seven women (3.1%) had MP by direct microscopy while 11 (4.8%) were MP positive with the qualitative immunoassay test. One hundred and eighty-five (82%) of the women were literate while 128 (57%) used insecticide treated mosquito nets in their homes. The mean PCV of the women with positive MP was 30.57 ± 2.26 as against 32.89 ± 2.45 for those without parasitemia (P < 0.05). The prevalence of asymptomatic malaria parasitemia in the study group was low but there was associated anemia in those with parasitemia. The use of intermittent preventive treatment is recommended for all pregnant women including those who are asymptomatic to forestall complications like maternal anemia.

Malaria parasitaemia among pregnant women in a rural community of eastern Nigeria; need for combined measures

Malaria in pregnancy is a major contributor to adverse maternal and perinatal outcome. In hyper endemic areas like ours, it is a common cause of anaemia in pregnancy in both immune and non-immune individuals and is aggravated by poor socioeconomic circumstances. The aim of this study is to assess the prevalence of asymptomatic malaria parasitaemia among pregnant women in a rural setting. 272 pregnant women, aged between 18 and 40 years in some remote rural areas of Ebonyi State, Nigeria were recruited between January 2007 and March 2008.Their blood samples were collected and examined for malaria parasite, haemoglobin and packed cell volume using standard methods. Our results showed 59.9% prevalence of parasitaemia with the highest prevalence occurring in the first trimester [84.1%]. Among the positive cases, mild parasitaemia was recorded in 47.2% moderate parasitaemia in 37.4% while severe parasitaemia was recorded in 15.3% of cases. These differences were statistically significant [P<0.016]. Furthermore the distribution of malaria densities in different gravidity groups showed an inverse relationship, 45.4% in primigravidae, [31.9%] in secundigravidae and [10.4%] among people with more than five pregnancies. These findings were statistically significant [P<0.0001]. The prevalence of anaemia in pregnancy in this study was 62.4%. Apart from the use of nets, drugs and vector control, the prevention of malaria in pregnancy in very poor socioeconomic settings should make provision for nutritional support.

Asymptomatic Plasmodium parasitaemia in pregnant Nigerian women: almost a decade after Roll Back Malaria

Malaria during pregnancy is a major cause of fetal and maternal morbidity and mortality. In malaria-endemic areas, the condition may remain asymptomatic but is still associated with complications. The objective of this study was to determine the prevalence of asymptomatic malaria parasitaemia and its relationship with various sociodemographic characteristics. The study was performed at three hospitals in Enugu, the centre of southeast Nigeria, during the rainy season between March 2006 and October 2007. Pregnant women attending the antenatal clinic at the index pregnancy were randomly selected and counseled, and peripheral blood samples were collected for malaria parasite and packed cell volume estimation. Age, parity, gestational age at booking, degree of anaemia and parasite density were recorded. Of 125 pregnant women tested, 73 had microscopic Plasmodium parasitaemia, giving a prevalence of 58.4%. Asymptomatic malaria parasitaemia was more common in primigravidae, in the second trimester and in the younger age group. Anaemia in pregnancy was prevalent (55.2%) and there was no significant difference in the density of parasitaemia in those with mild, moderate and severe anaemia. The prevalence of Plasmodium parasitaemia in pregnant Nigerian women is still very high nearly a decade after Roll Back Malaria. It is therefore pertinent to reappraise Roll Back Malaria strategies or to design a more effective programme for the prevention and treatment of malaria in pregnancy.

An investigation of symptomatic malaria parasitaemia and anaemia in nursery and primary school children in Buea District Cameroon.

To investigate the prevalence of asymptomatic malaria parasitaemia and anemia in nursery and primary school children and correlate parasite density with haemoglobin levels. Cross sectional study. Samples were collected from children attending the Saint Theresa's bilingual school and the Government Primary school, Buea, South West Province, Cameroon. 297 nursery and primary school children two to 11 years old selected based on parental consent. MAIN OUTOME MEASURES: Relationship between asymptomatic malaria and anaemia. The prevalence of asymptomatic malaria in children was 30.3%. Parasite prevalence and density was independent of age and sex (p > 0.05). The mean haemoglobin level for parasitaemic children was 11.9 g/dl (+/- SD1.1) compared with 12.1 g/dl (+/- 1.2) for non-parasitaemic children. The difference was not significant (t = 1.918, p > 0.05). Anaemia when present was mild. No correlation was found between malaria parasite density and haemoglobin levels (r = -0.065; p > 0.05). Asymptomatic malaria was accompanied by low grade parasitaemia, which did not seem to have a significant effect on haemoglobin levels.

Utility of intradermal blood smear in the detection of asymptomatic malaria parasitaemia in pregnancy

We evaluated the usefulness of intradermal smear microscopy (IDS) in the detection of asymptomatic malaria parasitaemia in pregnancy. Peripheral venous blood (PVB) served as control. The preference for the collection technique of dermal blood was also assessed. One hundred and fifty (150) asymptomatic women were recruited. They had both intradermal smear and peripheral venous blood smear were made for all patients. Measures of test validity included sensitivity, specificity and accuracy rate. Test of statistical significance was with Yates correlation at 95% confidence limit. The prevalence of asymptomatic malaria parasitaemia was higher using intradermal smear (35.3% vs 33.3%) though this was not statistically significant. Intradermal smear had a sensitivity of 40% and specificity of 67%. The positive predictive value was 37.8% with accuracy rate of 58%. 41% of participants preferred the technique of collection of intradermal blood. Intradermal smear appears to have no usefulness in the detection of asymptomatic malaria parasitaemia in pregnancy. However, we recommend more studies on its value in pregnancy, especially amongst symptomatic pregnant women.