scholarly journals Evaluation of the Antigenic Diversity of Placenta-Binding Plasmodium falciparum Variants and the Antibody Repertoire among Pregnant Women

2010 ◽  
Vol 78 (5) ◽  
pp. 1963-1978 ◽  
Author(s):  
Mirja Hommel ◽  
Salenna R. Elliott ◽  
Viju Soma ◽  
Greg Kelly ◽  
Freya J. I. Fowkes ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Pregnant Women ◽  
Vaccine Development ◽  
Malaria In Pregnancy ◽  
Antigenic Diversity ◽  
Molecular Approaches ◽  
Major Antigen ◽  
Different Populations ◽  
High Level ◽  
In Pregnancy

ABSTRACTPregnant women are infected by specific variants ofPlasmodium falciparumthat adhere and accumulate in the placenta. Using serological and molecular approaches, we assessed the global antigenic diversity of surface antigens expressed by placenta-binding isolates to better understand immunity to malaria in pregnancy and evolution of polymorphisms and to inform vaccine development. We found that placenta-binding isolates originating from all major regions where malaria occurs were commonly recognized by antibodies in different populations of pregnant women. There was substantial antigenic overlap and sharing of epitopes between isolates, including isolates from distant geographic locations, suggesting that there are limitations to antigenic diversity; however, differences between populations and isolates were also seen. Many women had cross-reactive antibodies and/or a broad repertoire of antibodies to different isolates. Studying VAR2CSA as the major antigen expressed by placenta-binding isolates, we identified antibody epitopes encoded by variable sequence blocks in the DBL3 domain. Analysis of globalvar2csaDBL3 sequences demonstrated that there was extensive sharing of variable blocks between Africa, Asia, Papua New Guinea, and Latin America, which likely contributes to the high level of antigenic overlap between different isolates. However, there was also evidence of geographic clustering of sequences and differences in VAR2CSA sequences between populations. The results indicate that there is limited antigenic diversity in placenta-binding isolates and may explain why immunity to malaria in pregnancy can be achieved after exposure during one pregnancy. Inclusion of a limited number of variants in a candidate vaccine may be sufficient for broad population coverage, but geographic considerations may also have to be included in vaccine design.

scholarly journals Pathogenesis of malaria in pregnancy

2008 ◽  
Vol 29 (4) ◽  
pp. 204
Author(s):  
Steven R Meshnick ◽  
Stephen J Rogerson
Keyword(s):  
Plasmodium Falciparum ◽  
Pregnant Women ◽  
Birth Outcomes ◽  
Preventive Therapy ◽  
Malaria In Pregnancy ◽  
Bed Nets ◽  
Common Disease ◽  
Protective Measures ◽  
Poor Countries ◽  
In Pregnancy

Even though we have good tools to prevent and treat malaria, it remains a tragically common disease in poor countries, especially in Africa. Pregnant women are particularly susceptible to malaria, causing anaemia and poor birth outcomes. There is marked sequestration of Plasmodium falciparum-infected erythrocytes (IEs) in the placenta, but the pathogenesis of malaria in pregnancy is still incompletely understood. Both intermittent preventive therapy and insecticide-impregnated bed nets are effective protective measures, but new measures are also needed.

scholarly journals Risk factors for Plasmodium falciparum infection in pregnant women in Burkina Faso: a community-based cross-sectional survey

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Jean Baptiste Yaro ◽  
Alphonse Ouedraogo ◽  
Amidou Diarra ◽  
Salif Sombié ◽  
Z. Amidou Ouedraogo ◽  
...  
Keyword(s):  
Risk Factors ◽  
Plasmodium Falciparum ◽  
Burkina Faso ◽  
Pregnant Women ◽  
Malaria Control ◽  
Dry Season ◽  
Malaria In Pregnancy ◽  
Wet Season ◽  
Cross Sectional ◽  
In Pregnancy

Abstract Background Malaria in pregnancy remains a public health problem in sub-Saharan Africa. Identifying risk factors for malaria in pregnancy could assist in developing interventions to reduce the risk of malaria in Burkina Faso and other countries in the region. Methods Two cross-sectional surveys were carried out to measure Plasmodium falciparum infection using microscopy in pregnant women in Saponé Health District, central Burkina Faso. Data were collected on individual, household and environmental variables and their association with P. falciparum infection assessed using multivariable analysis. Results A total of 356 pregnant women were enrolled in the surveys, 174 during the dry season and 182 during the wet season. The mean number of doses of sulfadoxine–pyrimethamine for Intermittent Preventive Treatment in pregnancy (IPTp-SP) was 0.4 doses during the first trimester, 1.1 doses at the second and 2.3 doses at the third. Overall prevalence of P. falciparum infection by microscopy was 15.7%; 17.8% in the dry season and 13.7% in the wet season. 88.2% of pregnant women reported sleeping under an insecticide-treated net (ITN) on the previous night. The odds of P. falciparum infection was 65% lower in women who reported using an ITN compared to those that did not use an ITN (Odds ratio, OR = 0.35, 95% CI 0.14–0.86, p = 0.02). IPTp-SP was also associated with reduced P. falciparum infection, with each additional dose of IPTp-SP reducing the odds of infection by 44% (OR = 0.56, 95% CI 0.39–0.79, p = 0.001). Literate women had a 2.54 times higher odds of P. falciparum infection compared to illiterate women (95% CI 1.31–4.91, p = 0.006). Conclusions The prevalence of P. falciparum infection among pregnant women remains high in Burkina Faso, although use of IPTp-SP and ITNs were found to reduce the odds of infection. Despite this, compliance with IPTp-SP remains far from that recommended by the National Malaria Control Programme and World Health Organization. Behaviour change communication should be strengthened to encourage compliance with protective malaria control tools during pregnancy.

scholarly journals Global genetic diversity of var2csa in Plasmodium falciparum with implications for malaria in pregnancy and vaccine development

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Ernest Diez Benavente ◽  
Damilola R. Oresegun ◽  
Paola Florez de Sessions ◽  
Eloise M. Walker ◽  
Cally Roper ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Plasmodium Falciparum ◽  
Vaccine Development ◽  
Malaria In Pregnancy ◽  
In Pregnancy

scholarly journals Risk Factors for Plasmodium Falciparum Infection in Pregnant Women in Burkina Faso: A Community-Based Malaria Cross-Sectional Survey

2021 ◽  
Author(s):  
Jean Baptiste Yaro ◽  
Alphonse Ouedraogo ◽  
Amidou Diarra ◽  
Salif Sombié ◽  
Z Amidou Ouedraogo ◽  
...  
Keyword(s):  
Risk Factors ◽  
Plasmodium Falciparum ◽  
Burkina Faso ◽  
Pregnant Women ◽  
Malaria Control ◽  
Dry Season ◽  
Malaria In Pregnancy ◽  
Wet Season ◽  
Cross Sectional ◽  
In Pregnancy

Abstract Background: Malaria in pregnancy remains a public health problem in sub-Saharan Africa. Identifying risk factors for malaria in pregnancy could assist in developing interventions to reduce the risk of malaria in Burkina Faso and other countries in the region.Methodology: Two cross-sectional surveys were carried out to measure Plasmodium falciparum infection using microscopy in pregnant women in Saponé Health District, central Burkina Faso. Data were collected on individual, household and environmental variables and their association with P. falciparum infection assessed using multivariate analysis. Results: A total of 356 pregnant women were enrolled in the surveys, 174 during the dry season and 182 during the wet season. The mean number of doses of sulphadoxine pyrimethamine for Intermittent Preventive Treatment in pregnancy (IPTp-SP) was 0.4 doses during the first trimester, 1.1 doses at the second and 2.3 doses at the third. Overall prevalence of P. falciparum infection by microscopy was 15.7%; 17.8% in the dry season and 13.7% in the wet season. 88.2% of pregnant women reported sleeping under an insecticide-treated net on the previous night. P. falciparum infection risk in pregnancy was reduced in those women who reported using an ITN (Odds ratio, OR=0.31, 95% CI 0.12-0.79, p=0.02) and an increasing number of IPTp-SP doses during pregnancy, with each additional dose reducing the odds by 40% (OR=0.59, 95% CI 0.43–0.81, p<0.001). ConclusionThe prevalence of P. falciparum infection among pregnant women remains high in Burkina Faso although use of IPTp-SP and ITNs were found to reduce the odds of infection. Despite this, compliance with IPTp remains far from that recommended by the National Malaria Control Programme and World Health Organization. Behaviour change communication should be improved to encourage compliance with protective malaria control tools during pregnancy.

scholarly journals Malaria in pregnancy in Hodiedah, Republic of Yemen

2002 ◽  
Vol 8 (2-3) ◽  
pp. 245-253
Author(s):  
A. M. Assabri ◽  
A. A. Muharram
Keyword(s):  
Plasmodium Falciparum ◽  
Pregnant Woman ◽  
Pregnant Women ◽  
Causative Agent ◽  
Clinical Manifestations ◽  
Malaria In Pregnancy ◽  
Laboratory Investigations ◽  
The Republic ◽  
In Pregnancy ◽  
Structured Questionnaire

In the Republic of Yemen, Plasmodium falciparum is the predominant causative agent of malaria and is associated with adverse consequences for pregnant women and their babies. The prevalence and clinical manifestations of malaria among 500 pregnant [260] and non-pregnant [240] women were compared. Clinical examinations, laboratory investigations and a structured questionnaire were used to collect data. The prevalence of malaria was higher among pregnant women [55%] than non-pregnant women [20%]. Anaemia was significantly more prevalent among pregnant woman than non-pregnant women and also more prevalent in pregnant women with malaria than non-pregnant women with malaria.

scholarly journals Acceptability of single screening and treatment policy for the control of malaria in pregnancy: perceptions of providers and pregnant women from selected health facilities in Lindi region, Tanzania

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Chonge Kitojo ◽  
Frank Chacky ◽  
Emmanuel S. Kigadye ◽  
Joseph P. Mugasa ◽  
Abdallah Lusasi ◽  
...  
Keyword(s):  
Pregnant Women ◽  
Health Facilities ◽  
Malaria In Pregnancy ◽  
National Guidelines ◽  
Qualitative And Quantitative ◽  
Main Challenge ◽  
Malaria Rapid Diagnostic Tests ◽  
Experienced Pain ◽  
Care Workers ◽  
In Pregnancy

Abstract Background Tanzania started implementing single screening and treatment (SST) for all pregnant women attending their first antenatal care (ANC) visits in 2014, using malaria rapid diagnostic tests (RDTs) and treating those who test positive according to the national guidelines. However, there is a paucity of data to show the acceptability of SST to both pregnant women and health care workers (HCWs), taking into consideration the shortage of workers and the added burden of this policy to the health system. This study assessed the perceptions and opinions of health service users and providers to determine the acceptability of SST policy. Methods Pregnant women and HCWs in eight health facilities in two districts of Lindi region (Kilwa and Lindi) were interviewed using semi-structured questionnaires with open and close-ended questions. Both qualitative and quantitative data were collected, including demographic characteristics, women’s experience, their perception on SST and challenges they face when receiving services for malaria offered at ANC. Experience of HCWs regarding the implementation of SST as part of routine services and the challenges encountered when providing ANC services for malaria in pregnancy (MIP) were also assessed. Results Of the 143 pregnant women interviewed, 97% viewed testing favourably and would wish to be tested for malaria again, while 95% were satisfied with services and reasons for testing during the first ANC visit. Nearly all (99%) would recommend their fellow pregnant women to be tested for malaria and all women recommended that the Ministry of Health should continue the SST strategy. This was despite the fact that 76% of the women experienced pain and 16% had anxiety as a result of finger prick. Sixteen HCWs (mostly nurses) were interviewed; they also viewed SST implementation favourably and reported feeling empowered to use RDTs for malaria screening. The main challenge identified by HCWs was that nurses are not allowed to prescribe anti-malarials to women who test positive and need to refer them to the outpatient department for treatment. Conclusion SST was considered an acceptable approach to control MIP by HCWs and pregnant women, and they recommended the continuation of the policy. In addition, consideration should be given to implementing a task-shifting policy to allow nurses to dispense anti-malarials to pregnant women.

Treatment of malaria in pregnant women with quinine

1927 ◽  
Vol 23 (3) ◽  
pp. 350-350
Author(s):  
A. Timofeev
Keyword(s):  
Pregnant Women ◽  
Malaria In Pregnancy ◽  
In Pregnancy

To refute the opinion among physicians that quinine therapy of malaria in pregnancy threatens the preservation of the latter, Canton Eliseo showed by experiments on pregnant rabbits that the administration of 2-4 centigrams of chinini muriatici pro kilo does not cause abortion.

scholarly journals Malaria in pregnancy in rural Mozambique: the role of parity, submicroscopic and multiple Plasmodium falciparum infections

2002 ◽  
Vol 7 (1) ◽  
pp. 19-28 ◽  
Author(s):  
Francisco Saute ◽  
Clara Menendez ◽  
Alfredo Mayor ◽  
John Aponte ◽  
Xavier Gomez-Olive ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Malaria In Pregnancy ◽  
In Pregnancy

Asymptomatic malaria and anemia among pregnant women during high and low malaria transmission seasons in Burkina Faso: household-based cross-sectional surveys in Burkina Faso, 2013–2017

2020 ◽  
Author(s):  
Toussaint Rouamba ◽  
Sékou Samadoulougou ◽  
Mady Ouédraogo ◽  
Hervé Hien ◽  
Halidou Tinto ◽  
...  
Keyword(s):  
Burkina Faso ◽  
Pregnant Women ◽  
Malaria Transmission ◽  
Malaria In Pregnancy ◽  
Asymptomatic Malaria ◽  
Cross Sectional ◽  
Transmission Season ◽  
Asymptomatic Carriage ◽  
Low Malaria Transmission ◽  
In Pregnancy

Abstract Background: Malaria in endemic countries is often asymptomatic during pregnancy, but it has substantial consequences for both the mother and her unborn baby. In Burkina Faso, the prevalence and risk factors of asymptomatic malaria in pregnancy and its main consequence, anemia, during high and low malaria transmission seasons is underexplored at the household level.Methods: Data of 1751 pregnant women from October 2013 to March 2014 and 1931 pregnant women from April 2017 to June 2017 were drawn from two cross-sectional household surveys conducted in 24 health districts of Burkina Faso. Pregnant women were tested for malaria in their household after consenting. Asymptomatic carriage was defined as a positive result from malaria rapid diagnostic tests in the absence of malaria symptoms. Anemia was defined as hemoglobin level less than 11 g/dL.Results: Prevalence of asymptomatic malaria in pregnancy was estimated at 23.9% (95%CI: 20.2–28.0) during the high transmission season (October–November) in 2013. During the low transmission season, it was 12.7% (95%CI: 10.9–14.7) between December and March in 2013–2014 and halved (6.4%; 95%CI: 5.3–7.6) between April and June 2017. Anemia prevalence was estimated at 43.7% (95%CI: 39.3–48.3) during the high transmission season in 2013. During the low transmission season, it was 32.7% (95%CI: 30.1–35.5) between December and March 2013–2014 and 46.6% (95%CI: 44.3–48.9) between April and June, 2017.Conclusion: Prevalence of asymptomatic malaria in pregnancy was significantly higher during the high malaria transmission season while anemia prevalence was lower. Our study provides an opportunity to assess the prevalence of asymptomatic carriage and one of its main consequences, anemia, among pregnant women at the community level throughout the year. In order to mitigate the harmful effects of asymptomatic carriage for both the mother and fetus, health programs aimed at increasing the number of women coming into contact with health workers are necessary.

scholarly journals Analysis of Plasmodium falciparum Pfcrt and Pfmdr1 genes in parasite isolates from asymptomatic individuals in Southeast Nigeria 11 years after withdrawal of chloroquine

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Moses N. Ikegbunam ◽  
Charles N. Nkonganyi ◽  
Bolaji N. Thomas ◽  
Charles O. Esimone ◽  
Thirumalaisamy P. Velavan ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Pregnant Women ◽  
Direct Sequencing ◽  
Artemisinin Combination Therapy ◽  
First Line ◽  
Mutant Genotype ◽  
Current Prevalence ◽  
New Strategy ◽  
Asymptomatic Individuals ◽  
High Level

Abstract Background A reversal of chloroquine (CQ) resistance following a period of withdrawal has raised the possibility of its re-introduction. This study evaluated the current prevalence of Pfcrt and Pfmdr1 alleles in Plasmodium falciparum isolates, 11 years after CQ withdrawal in Southeast Nigeria. Methods Filter-paper blood samples were collected from 725 non-febrile individuals, comprising 250 children (≤ 12 years), 250 pregnant women and 225 other adults, between October 2014 and February 2015 in Nnewi town, Southeast Nigeria. Nested PCR followed by direct sequencing was employed for the genotyping of Pfcrt and Pfmdr1 genes. Results A total of 103 parasites-positive samples were recovered, comprising of 48 (19.20%) among children, 20 (20.00%) among pregnant women and 35 (15.50%) among other adults cohort. The frequency of the mutant genotype of Pfcrt 76T, 75E and 74I was 94.50% each. Parasite isolates from children had a frequency of 100% for mutant alleles in all Pfcrt codons while isolates from pregnant women and other adults had a frequency of 91% each in all codons. Haplotype distribution of pfcrt gene were 5.45, 0.00 and 76.37% for CVMNK, SVMNT and CVIET, respectively. For Pfmdr1 gene, the frequency of 86Y, 184F and 1246Y mutant alleles were 8.54, 29.27 and 3.66%, respectively. Amongst the Pfmdr1 haplotypes analysed, NFD had the highest frequency of 24.4%, followed by YFD at 6.10%. NYF and NYY occurred the least (1.20%). Conclusion The high level of Pfcrt mutations is suggestive of a sustained CQ pressure on P. falciparum isolates in the study area, despite the change of first line treatment from CQ to artemisinin combination therapy for 11 years. A new strategy to ensure the complete withdrawal of CQ from the country is recommended.

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