-
Malaria Journal Oct 2011During pregnancy, malaria infection with Plasmodium falciparum or Plasmodium vivax is related to adverse maternal health and poor birth outcomes. Diagnosis of malaria,... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
During pregnancy, malaria infection with Plasmodium falciparum or Plasmodium vivax is related to adverse maternal health and poor birth outcomes. Diagnosis of malaria, during pregnancy, is complicated by the absence or low parasite densities in peripheral blood. Diagnostic methods, other than microscopy, are needed for detection of placental malaria. Therefore, the diagnostic accuracy of rapid diagnostic tests (RDTs), detecting antigen, and molecular techniques (PCR), detecting DNA, for the diagnosis of Plasmodium infections in pregnancy was systematically reviewed.
METHODS
MEDLINE, EMBASE and Web of Science were searched for studies assessing the diagnostic accuracy of RDTs, PCR, microscopy of peripheral and placental blood and placental histology for the detection of malaria infection (all species) in pregnant women.
RESULTS
The results of 49 studies were analysed in metandi (Stata), of which the majority described P. falciparum infections. Although both placental and peripheral blood microscopy cannot reliably replace histology as a reference standard for placental P. falciparum infection, many studies compared RDTs and PCR to these tests. The proportion of microscopy positives in placental blood (sensitivity) detected by peripheral blood microscopy, RDTs and PCR are respectively 72% [95% CI 62-80], 81% [95% CI 55-93] and 94% [95% CI 86-98]. The proportion of placental blood microscopy negative women that were negative in peripheral blood microscopy, RDTs and PCR (specificity) are 98% [95% CI 95-99], 94% [95% CI 76-99] and 77% [95% CI 71-82]. Based on the current data, it was not possible to determine if the false positives in RDTs and PCR are caused by sequestered parasites in the placenta that are not detected by placental microscopy.
CONCLUSION
The findings suggest that RDTs and PCR may have good performance characteristics to serve as alternatives for the diagnosis of malaria in pregnancy, besides any other limitations and practical considerations concerning the use of these tests. Nevertheless, more studies with placental histology as reference test are urgently required to reliably determine the accuracy of RDTs and PCR for the diagnosis of placental malaria. P. vivax-infections have been neglected in diagnostic test accuracy studies of malaria in pregnancy.
Topics: Antigens, Protozoan; DNA, Protozoan; Diagnostic Tests, Routine; Female; Histocytochemistry; Humans; Malaria, Falciparum; Malaria, Vivax; Microscopy; Parasitemia; Placenta; Plasmodium falciparum; Plasmodium vivax; Polymerase Chain Reaction; Pregnancy; Pregnancy Complications, Infectious
PubMed: 22035448
DOI: 10.1186/1475-2875-10-321 -
Malaria Journal Apr 2024In sub-Saharan Africa (SSA), Plasmodium falciparum causes most of the malaria cases. Despite its crucial roles in disease severity and drug resistance, comprehensive... (Meta-Analysis)
Meta-Analysis Review
Plasmodium falciparum genetic diversity and multiplicity of infection based on msp-1, msp-2, glurp and microsatellite genetic markers in sub-Saharan Africa: a systematic review and meta-analysis.
BACKGROUND
In sub-Saharan Africa (SSA), Plasmodium falciparum causes most of the malaria cases. Despite its crucial roles in disease severity and drug resistance, comprehensive data on Plasmodium falciparum genetic diversity and multiplicity of infection (MOI) are sparse in SSA. This study summarizes available information on genetic diversity and MOI, focusing on key markers (msp-1, msp-2, glurp, and microsatellites). The systematic review aimed to evaluate their influence on malaria transmission dynamics and offer insights for enhancing malaria control measures in SSA.
METHODS
The review was conducted following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Two reviewers conducted article screening, assessed the risk of bias (RoB), and performed data abstraction. Meta-analysis was performed using the random-effects model in STATA version 17.
RESULTS
The review included 52 articles: 39 cross-sectional studies and 13 Randomized Controlled Trial (RCT)/cohort studies, involving 11,640 genotyped parasite isolates from 23 SSA countries. The overall pooled mean expected heterozygosity was 0.65 (95% CI: 0.51-0.78). Regionally, values varied: East (0.58), Central (0.84), Southern (0.74), and West Africa (0.69). Overall pooled allele frequencies of msp-1 alleles K1, MAD20, and RO33 were 61%, 44%, and 40%, respectively, while msp-2 I/C 3D7 and FC27 alleles were 61% and 55%. Central Africa reported higher frequencies (K1: 74%, MAD20: 51%, RO33: 48%) than East Africa (K1: 46%, MAD20: 42%, RO33: 31%). For msp-2, East Africa had 60% and 55% for I/C 3D7 and FC27 alleles, while West Africa had 62% and 50%, respectively. The pooled allele frequency for glurp was 66%. The overall pooled mean MOI was 2.09 (95% CI: 1.88-2.30), with regional variations: East (2.05), Central (2.37), Southern (2.16), and West Africa (1.96). The overall prevalence of polyclonal Plasmodium falciparum infections was 63% (95% CI: 56-70), with regional prevalences as follows: East (62%), West (61%), Central (65%), and South Africa (71%).
CONCLUSION
The study shows substantial regional variation in Plasmodium falciparum parasite genetic diversity and MOI in SSA. These findings suggest a need for malaria control strategies and surveillance efforts considering regional-specific factors underlying Plasmodium falciparum infection.
Topics: Humans; Merozoite Surface Protein 1; Plasmodium falciparum; Antigens, Protozoan; Protozoan Proteins; Genetic Markers; Genetic Variation; Malaria, Falciparum; Genotype; Alleles; Microsatellite Repeats; South Africa
PubMed: 38589874
DOI: 10.1186/s12936-024-04925-y -
Socioeconomic development as an intervention against malaria: a systematic review and meta-analysis.Lancet (London, England) Sep 2013Future progress in tackling malaria mortality will probably be hampered by the development of resistance to drugs and insecticides and by the contraction of aid budgets.... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Future progress in tackling malaria mortality will probably be hampered by the development of resistance to drugs and insecticides and by the contraction of aid budgets. Historically, control was often achieved without malaria-specific interventions. Our aim was to assess whether socioeconomic development can contribute to malaria control.
METHODS
We did a systematic review and meta-analysis to assess whether the risk of malaria in children aged 0-15 years is associated with socioeconomic status. We searched Medline, Web of Science, Embase, the Cochrane Database of Systematic Reviews, the Campbell Library, the Centre for Reviews and Dissemination, Health Systems Evidence, and the Evidence for Policy and Practice Information and Co-ordinating Centre evidence library for studies published in English between Jan 1, 1980, and July 12, 2011, that measured socioeconomic status and parasitologically confirmed malaria or clinical malaria in children. Unadjusted and adjusted effect estimates were combined in fixed-effects and random-effects meta-analyses, with a subgroup analysis for different measures of socioeconomic status. We used funnel plots and Egger's linear regression to test for publication bias.
FINDINGS
Of 4696 studies reviewed, 20 met the criteria for inclusion in the qualitative analysis, and 15 of these reported the necessary data for inclusion in the meta-analysis. The odds of malaria infection were higher in the poorest children than in the least poor children (unadjusted odds ratio [OR] 1·66, 95% CI 1·35-2·05, p<0·001, I(2)=68%; adjusted OR 2·06, 1·42-2·97, p<0·001, I(2)=63%), an effect that was consistent across subgroups.
INTERPRETATION
Although we would not recommend discontinuation of existing malaria control efforts, we believe that increased investment in interventions to support socioeconomic development is warranted, since such interventions could prove highly effective and sustainable against malaria in the long term.
FUNDING
UK Department for International Development.
Topics: Adolescent; Adult; Africa; Aged; Child; Child, Preschool; Cost of Illness; Economic Development; Gross Domestic Product; Humans; Infant; Malaria, Falciparum; Middle Aged; Poverty; Socioeconomic Factors; Young Adult
PubMed: 23790353
DOI: 10.1016/S0140-6736(13)60851-X -
Scientific Reports May 2021Felidae as definitive hosts for Toxoplasma gondii play a major role in transmission to all warm-blooded animals trough oocysts dissemination. Therefore the current... (Meta-Analysis)
Meta-Analysis
Felidae as definitive hosts for Toxoplasma gondii play a major role in transmission to all warm-blooded animals trough oocysts dissemination. Therefore the current comprehensive study was performed to determine the global status of T. gondii infection in domestic and wild felids aiming to provide comprehensive data of interest for further intervention approaching the One Health perspective. Different databases were searched by utilizing particular key words for publications related to T. gondii infecting domestic and wild feline host species, worldwide, from 1970 to 2020. The review of 337 reports showed that the seroprevalence of T. gondii in domestic cats and wild felids was estimated in 37.5% (95% CI 34.7-40.3) (I = 98.3%, P < 0.001) and 64% (95% CI 60-67.9) (I = 88%, P < 0.0001), respectively. The global pooled prevalence of oocysts in the fecal examined specimens from domestic cats was estimated in 2.6% (95% CI 1.9-3.3) (I = 96.1%, P < 0.0001), and that in fecal samples from wild felids was estimated in 2.4% (95% CI 1.1-4.2) (I = 86.4%, P < 0.0001). In addition, from 13,252 examined soil samples in 14 reviewed studies, the pooled occurrence of T. gondii oocysts was determined in 16.2% (95% CI 7.66-27.03%). The observed high rates of anti-T. gondii antibodies seroprevalence levels and oocyst excretion frequency in the felids, along with soil (environmental) contamination with oocysts may constitute a potential threat to animal and public health, and data will result of interest in further prophylaxis programs.
Topics: Animals; Feces; Felidae; Humans; Oocysts; Prevalence; Public Health; Soil; Toxoplasma; Toxoplasmosis; Toxoplasmosis, Animal
PubMed: 33947922
DOI: 10.1038/s41598-021-89031-8 -
Journal of Infection in Developing... Dec 2014Although toxoplasmosis in immunocompetent individuals is generally asymptomatic, in immunocompromised patients (HIV/AIDS, cancer, and transplant patients), it can lead... (Meta-Analysis)
Meta-Analysis Review
Although toxoplasmosis in immunocompetent individuals is generally asymptomatic, in immunocompromised patients (HIV/AIDS, cancer, and transplant patients), it can lead to serious pathological effects. This study included a systematic review and meta-analysis to comprehensively assess the seroprevalence rate of Toxoplasma infection in immunocompromised patients in Iran. Electronic English and Persian databases (PubMed, Google Scholar, ScienceDirect, Scopus, Magiran, Scientific Information Database [SID], IranMedex, and IranDoc), parasitology congresses, and projects and theses of Iranian medical universities, were systematically searched from 1997 to 2013 (published or unpublished data). In this paper, several studies that used serological methods for diagnosis of toxoplasmosis were selected. Analysis of seroprevalence estimates was pooled using a random-effects meta-analysis. Twenty-two studies, comprising 2,805 individuals, were included in the meta-analysis. Overall seroprevalence rate of Toxoplasma infection in Iranian immunocompromised patients was 50.01% (95% confidence interval, 43.85 to 56.17); however, there was significant heterogeneity among study groups. The results showed that seroprevalence rate of toxoplasmosis among transplant recipients, HIV/AIDS, and cancer patients in Iran was 55.1%, 50.05%, and 45.06%, respectively. In addition, IgM seroprevalence rate was estimated to be 4.85% (95% confidence interval, 2.22 to 8.41). This systematic review and meta-analysis identified a high seroprevalence rate of Toxoplasma infection among immunocompromised patients (50%). Consideration of management, design and provision of appropriate control measures of toxoplasmosis is highly recommended.
Topics: Antibodies, Protozoan; HIV Infections; Humans; Immunocompromised Host; Immunoglobulin G; Iran; Neoplasms; Seroepidemiologic Studies; Toxoplasma; Toxoplasmosis; Transplant Recipients
PubMed: 25500647
DOI: 10.3855/jidc.4796 -
Transfusion Medicine Reviews Jul 2016Transfusion-transmissible infections include pathogens that may cause severe and debilitating diseases. Toxoplasmosis is a cosmopolitan neglected parasitic infection... (Meta-Analysis)
Meta-Analysis Review
Transfusion-transmissible infections include pathogens that may cause severe and debilitating diseases. Toxoplasmosis is a cosmopolitan neglected parasitic infection that can lead to severe complications including death in immune-compromised patients or following infection in utero. Multiple studies have demonstrated the transmission of Toxoplasma gondii by blood transfusion. The objective of this review was to comprehensively assess the seroprevalence rate of Toxoplasma in blood donors from a worldwide perspective. Seven electronic databases (PubMed, Science Direct, Web of Science, Scopus, Cochrane, Ovid, and Google Scholar) were searched using medical subject headings terms. A total of 43 records met the inclusion criteria in which 20,964 donors were tested during the period from January 1980 to June 2015. The overall weighted prevalence of exposure to toxoplasmosis in blood donors was 33% (95% confidence interval [CI], 28%-39%). The seroprevalences of immunoglobulin (Ig)M and both IgG and IgM antibodies were 1.8% (95% CI, 1.1%-2.4%) and 1.1% (95% CI, 0.3%-1.8%), respectively. The highest and the lowest seroprevalences of toxoplasmosis were observed in Africa (46%; 95% CI, 14%-78%) and in Asia (29%; 95% CI, 23%-35%), respectively. Brazil (75%) and Ethiopia (73%) were identified as countries with high seroprevalence. Because positive serology does not imply infectiousness and because seroprevalence is high in some nations, a positive serology test result alone cannot be used as an effective method for donor screening. Future research for methods to prevent transfusion-transmitted toxoplasmosis may derive benefit from studies conducted in areas of high endemicity.
Topics: Antibodies, Protozoan; Blood Donors; Humans; Immunoglobulin G; Immunoglobulin M; Seroepidemiologic Studies; Toxoplasmosis
PubMed: 27145927
DOI: 10.1016/j.tmrv.2016.03.002 -
Scientific Reports Apr 2022The dual effects of co-infection of Plasmodium spp. and hookworm on malaria remain under debate. This study investigated prevalence, prevalence odds ratio (POR) of... (Meta-Analysis)
Meta-Analysis
The dual effects of co-infection of Plasmodium spp. and hookworm on malaria remain under debate. This study investigated prevalence, prevalence odds ratio (POR) of co-infection and impact of co-infection on malaria parasite density and haemoglobin levels in comparison to Plasmodium mono-infection. The protocol for this systematic review and meta-analysis is registered at PROPERO under ID: CRD42020202156. Relevant literatures were obtained from PubMed, ISI Web of Science, and Scopus on 25 December 2020. Mean difference (MD) and confidence interval (CI) of malaria parasite density and haemoglobin were compared using a random effect model. Heterogeneity was assessed using Cochrane Q and I statistics. Publication bias was determined by visualising funnel plot asymmetry. Of 1756 articles examined, 22,191 malaria cases across 37 studies included 6096 cases of co-infection of Plasmodium spp. and hookworm. The pooled prevalence was 20% (95% CI 15-26%, I 99.6%, 37 studies) and was varied in terms of geographical region. Co-infection occurred by chance (OR 0.97, p 0.97, 95% CI 0.73-1.27, I 95%, 30 studies). The mean malaria parasite density for co-infection (478 cases) was similar to Plasmodium mono-infection (920 cases) (p 0.24, MD 0.86, 95% CI - 0.58-2.29, I 100%, 7 studies). The mean haemoglobin level for co-infection (90 cases) was similar to Plasmodium mono-infection (415 cases) (p 0.15, MD - 0.63, 95% CI - 1.49-0.23, I 98%, 4 studies). Co-infection was common and occurred by chance but varied by geographic region. Further studies are required to investigate the mechanism of hookworm infection on malaria severity. Additionally, detection of hookworm infections among patients with malaria in endemic areas of both diseases is recommended to prevent severe malaria.
Topics: Ancylostomatoidea; Animals; Coinfection; Hookworm Infections; Humans; Malaria; Parasites; Plasmodium; Prevalence
PubMed: 35477943
DOI: 10.1038/s41598-022-10569-2 -
Pathogens and Global Health Oct 2017Toxoplasmosis is an infection caused by the intracellular protozoan parasite Toxoplasma gondii, and is associated with clinically significant infection in... (Review)
Review
Toxoplasmosis is an infection caused by the intracellular protozoan parasite Toxoplasma gondii, and is associated with clinically significant infection in immunocompromised individuals. Vertical transmission during pregnancy can manifest as congenital toxoplasmosis in the neonate, and can have serious consequences. This review aims to describe the modalities for prophylaxis of toxoplasmosis in susceptible populations, and focuses on the following: (1) prophylaxis of congenital toxoplasmosis; (2) prophylaxis of toxoplasmosis in patients with HIV/AIDS; and (3) prophylaxis of toxoplasmosis in transplant recipients.
Topics: HIV Infections; Humans; Infectious Disease Transmission, Vertical; Toxoplasmosis; Transplant Recipients
PubMed: 28948861
DOI: 10.1080/20477724.2017.1370528 -
Journal of the European Academy of... Oct 2021In the late 90s, a sharp increase of treatment failures of Trichomonas vaginalis (TV) infections with metronidazole (MTZ) was reported, representing a problem due to... (Review)
Review
In the late 90s, a sharp increase of treatment failures of Trichomonas vaginalis (TV) infections with metronidazole (MTZ) was reported, representing a problem due to limited treatment options. We proposed to review the available evidence on the frequency of MTZ resistance by TV isolates and the relationship between treatment failure and in vitro resistance to MTZ. A systematic review based on the PRISMA guidelines was conducted by searching published studies in three different databases (PubMed, Scopus and Web of Science) up to December 2020. The extracted studies were uploaded to Covidence software; screening was guided based on inclusion and exclusion criteria. Additionally, different articles were included through other sources. For each article, study design, objectives, study population and key outcomes were summarized. We found 403 references from the databases and four extra studies. After duplicate removal and screening of title, abstract and full text, 27 studies were included. The selected studies were published between 1983 and 2019; all except one addressed only vaginal TV infection. We identified four major populations in vitro MTZ resistance: two studies evaluated female adolescents; other two assessed HIV-positive women. Fifteen studies considered MTZ resistance in newly diagnosed vaginal TV infection. Finally, eight articles studied in vitro susceptibility of isolates from women with clinical resistant trichomoniasis. High level of in vitro MTZ resistance was rare; low-moderate level was described in most of the cases. Although clinical resistance to MTZ of trichomoniasis was widely reported, there was a paucity of prospective controlled studies. Our review unveiled the need to standardize susceptibility testing, to define breakpoints for detection of MTZ-resistant isolates and to correlate with clinical outcome. It is important to establish criteria to define clinical resistance to MTZ. Such a consensus would foster the development of surveillance studies about clinical and microbiological response to MTZ treatment.
Topics: Adolescent; Drug Resistance; Female; Humans; Metronidazole; Prospective Studies; Trichomonas Infections; Trichomonas Vaginitis; Trichomonas vaginalis
PubMed: 34146427
DOI: 10.1111/jdv.17461 -
Preventive Veterinary Medicine Apr 2022Neospora caninum, an intracellular protozoan, has attracted much attention because of the etiology of reproductive disorders in cattle. Although numerous relevant... (Meta-Analysis)
Meta-Analysis Review
Neospora caninum, an intracellular protozoan, has attracted much attention because of the etiology of reproductive disorders in cattle. Although numerous relevant studies have been published, the overall prevalence of Neospora caninum infection among cattle in mainland China is still unknown, and associated risk factors need to be evaluated to establish preventive measures. We systematically searched four databases for epidemiologic studies that investigated the prevalence and associated risk factors of this parasite among cattle in mainland China. A total of 33,945 cattle from 51 studies were tested. The pooled prevalence of Neospora caninum among cattle in mainland China was 13.69% (95% CI: 10.86%-17.12%) through the random-effects model, which showed high heterogeneity, I = 98%. The analysis showed that Neospora infection-positive cows were 2.42 times more likely to abort than infection-negative cows (OR 2.42; 95% CI: 2.07-2.84). Our analysis indicated that Neospora-infection is widely distributed among cattle in China, which reinforces the importance of adequate prevention and control strategies to reduce economic losses for the cattle industry.
Topics: Animals; Antibodies, Protozoan; Cattle; Cattle Diseases; Coccidiosis; Female; Neospora; Prevalence; Risk Factors; Seroepidemiologic Studies
PubMed: 35255390
DOI: 10.1016/j.prevetmed.2022.105593