Effect of ABO Blood Group on Asymptomatic, Uncomplicated and Placental Plasmodium Falciparum Infection: Systematic Review and Meta-Analysis

BACKGROUND: Malaria clinical outcomes vary by erythrocyte characteristics, including ABO blood group, but the effect of ABO blood group on asymptomatic, uncomplicated and placental Plasmodium falciparum (P. falciparum) infection remains unclear. We explored effects of ABO blood group on asymptomatic, uncomplicated and placental falciparum infection in the published literature. METHODS: A systematic review and meta-analysis was performed using the preferred reporting items for systematic reviews and meta-analyses guidelines. Articles in Pubmed, Embase, Web of Science, CINAHL and Cochrane Library published before February 04, 2017 were searched without restriction. Studies were included if they reported P. falciparum infection incidence or prevalence, stratified by ABO blood group. RESULTS: Of 1923 articles obtained from the five databases (Embase = 728, PubMed = 620, Web of Science = 549, CINAHL = 14, Cochrane Library = 12), 42 met criteria for systematic review and 37 for meta-analysis. Most studies (n = 30) were cross-sectional, seven were prospective cohort, and five were case-control studies. Meta-analysis showed similar odds of uncomplicated P. falciparum infection among individuals with blood group A (summary odds ratio [OR] 0.96, 15 studies), B (OR 0.89, 15 studies), AB (OR 0.85, 10 studies) and non-O (OR 0.95, 17 studies) as compared to those with blood group O. Meta-analysis of four cohort studies also showed similar risk of uncomplicated P. falciparum infection among individuals with blood group non-O and those with blood group O (summary relative risk [RR] 1.03). Meta-analysis of six studies showed similar odds of asymptomatic P. falciparum infection among individuals with blood group A (OR 1.05), B (OR 1.03), AB (OR 1.23), and non-O (OR 1.07) when compared to those with blood group O. However, odds of active placental P. falciparum infection was significantly lower in primiparous women with non-O blood groups (OR 0.46, 95% confidence interval [CI] 0.23 - 0.69, I CONCLUSIONS: This study suggests that ABO blood group may not affect susceptibility to asymptomatic and/or uncomplicated P. falciparum infection. However, blood group O primiparous women appear to be more susceptible to active placental P. falciparum infection

Progress towards Elimination of HIV Mother-to-Child Transmission in the Dominican Republic from 1999 to 2011

In 1999, prevention of mother-to-child transmission (pMTCT) using antiretrovirals was introduced in the Dominican Republic (DR). Highly active antiretroviral therapy (HAART) was introduced for immunosuppressed persons in 2004 and for pMTCT in 2008. To assess progress towards MTCT elimination, data from requisitions for HIV nucleic acid amplification tests for diagnosis of HIV infection in perinatally exposed infants born in the DR from 1999 to 2011 were analyzed. The MTCT rate was 142/1,274 (11.1%) in 1999?2008 and 12/302 (4.0%) in 2009?2011 (P \u3c .001), with a rate of 154/1,576 (9.8%) for both periods combined. This decline was associated with significant increases in the proportions of women who received prenatal HAART (from 12.3% to 67.9%) and infants who received exclusive formula feeding (from 76.3% to 86.1%) and declines in proportions of women who received no prenatal antiretrovirals (from 31.9% to 12.2%) or received only single-dose nevirapine (from 39.5% to 19.5%). In 2007, over 95% of DR pregnant women received prenatal care, HIV testing, and professionally attended delivery. However, only 58% of women in underserved sugarcane plantation communities (2007) and 76% in HIV sentinel surveillance hospitals (2003?2005) received their HIV test results. HIV-MTCT elimination is feasible but persistent lack of access to critical pMTCT measures must be addressed

Forest plot showing the difference in the prevalence of asymptomatic/uncomplicated <i>P</i>. <i>falciparum</i> malaria between children infected with <i>S</i>. <i>haematobium</i> or <i>S</i>. <i>mansoni</i> and those not infected with <i>Schistosoma</i> in SSA.

<p>Forest plot showing the difference in the prevalence of asymptomatic/uncomplicated <i>P</i>. <i>falciparum</i> malaria between children infected with <i>S</i>. <i>haematobium</i> or <i>S</i>. <i>mansoni</i> and those not infected with <i>Schistosoma</i> in SSA.</p

Characteristics of the included studies.

<p>Characteristics of the included studies.</p

Mean haemoglobin differences between children co-infected with <i>S</i>. <i>haematobium</i> and asymptomatic/uncomplicated <i>P</i>. <i>falciparum</i> and those infected with only <i>P</i>. <i>falciparum</i>.

<p>Mean haemoglobin differences between children co-infected with <i>S</i>. <i>haematobium</i> and asymptomatic/uncomplicated <i>P</i>. <i>falciparum</i> and those infected with only <i>P</i>. <i>falciparum</i>.</p

Effect of <i>S</i>. <i>haematobium</i> infection on <i>P</i>. <i>falciparum</i> density in children in SSA.

<p>Effect of <i>S</i>. <i>haematobium</i> infection on <i>P</i>. <i>falciparum</i> density in children in SSA.</p

PRISMA diagram.

<p>Flow chart for study selection. Hb: Haemoglobin; SSA: sub-Saharan Africa; STH: Soil-transmitted helminths</p