Framework programme:

 7

Contract/Grant agreement number:

201588

EC contribution:

2.900.000 €

Duration:

48 months

Funding scheme:

Collaborative Project, STREP

Starting date:

01/03/2008

 

 

Keywords: Plasmodium vivax, malaria, pregnancy, gestation

Background

Malaria in pregnancy has been recently prioritised by the European Commission's Seventh Framework Programme (FP7). Approximately 25 million pregnant women exposed yearly to malaria live in areas where Plasmodium vivax is endemic. While the effects of falciparum malaria in pregnancy have been well characterised and are responsible for considerable maternal and infant morbidity and mortality, surprisingly little is known about the impact of P. vivax infection during gestation.

Recently, there have been reports from Latin America (3), Thailand (4) and India (5), suggesting that P. vivax infection may be associated with poor pregnancy outcomes, mainly maternal anaemia, low birth weight and miscarriage. These studies, mostly based on very small numbers, provide inconsistent information about P. vivax in pregnancy. Additionally, they provide only partial information on the epidemiological and clinical aspects of the infection in pregnancy.

Aims and expected results

To fill the knowledge gaps of P. vivax malaria in pregnancy, the PregVax project is carrying out a cohort observational study in pregnant women in five P. vivax-endemic countries, broadly representing most of the world’s P. vivax infections. Pregnant women are being enrolled in each site at the time of routine antenatal care visits and followed up at the health facility until delivery or end of pregnancy. P. vivax malaria parasitaemia is being assessed at enrolment, at every contact with the health facility and at delivery.

The main objective of the PregVax study is to describe the epidemiological and clinical features of P. vivax malaria in pregnancy. We will also determine if there are pregnancy-specific immune responses and characterise, genotypically and phenotypically, parasites of the placenta.

In a sub-sample of women, peripheral blood is being taken for immunological/ molecular studies and placental samples will be collected. To assess with precision the prevalence of infection at each site and to obtain sufficient numbers of pregnant women with P. vivax infection to determine the impact on birth weight, 2 000 pregnant women per site will be enrolled. Due to the likely low prevalence of P. vivax infection in pregnancy, the number of pregnant women with P. vivax per site will probably not be enough to assess the impact on pregnancy outcomes specifically for each site; therefore, a multicentre analysis will be used. In addition to the clinical-epidemiological studies, immunological analysis will be performed to unveil whether there are pregnancy-specific immune responses.

Compiling information in a methodologically standardised way will allow a precise assessment of the prevalence of P. vivax infection during gestation at each study site, and provide a description of P. vivax infection impact during pregnancy. Phenotypic and genotypic analyses of parasites from the placenta should reveal, respectively, their adhesive properties and whether the accumulation of P. vivax-infected erythrocytes in the placenta selects unique parasite populations.

Potential applications:

A more precise description of the impact of P. vivax malaria during gestation will help improve its clinical management. Accurate data on the prevalence and incidence of the infection is essential to guide control policies. Furthermore, elucidating the mechanisms involved in the pathology of P. vivax in pregnancy will help to develop specific control tools such as more effective drugs and vaccines.

Finally, understanding the mechanism involved in P. vivax malaria may also help to elucidate important gaps in the knowledge of falciparum infection in pregnancy.

Coordinator:

Dr. Clara Menéndez
Fundació Clínic per a la Rercerca Biomèdica
Barcelona
Spain
menendez@clinic.ub.es

Partners: