Impact of Helminth Infections During Pregnancy on Humoral Vaccine Immunogenicity in Infants

Impact of Helminth Infections During Pregnancy on Humoral Vaccine Immunogenicity in Infants

Helminth infection is associated with low vaccine immunogenicity. Pregnant women are particularly sensitive to helminth infection.

Since most vaccines are given shortly after birth, an effect of parasites on infant immunogenicity is of particular concern. Therefore, within this study the investigators aim to investigate if maternal infection influences vaccine immunogenicity in the newborn.

There is evidence that helminth infections during pregnancy affect the immune system of the mother and the unborn child. As a consequence, the antimicrobial- immune and vaccine- response of the infant may be deficient. The aim of the present study is to measure the influence of maternal helminth infection (schistosomal, filarial and intestinal helminth infection) on vaccine immunogenicity of their infants. The main focus is on immune responses of infants to vaccine antigens given as part of the expanded program on immunization (EPI) in Gabon at an age when infants are unlikely to be infected with helminths and are immunologically primed by their intrauterine life. The objective is to investigate if and which species of helminths during pregnancy have an effect on any of the EPI vaccine-induced immune responses.

Inclusion Criteria:

• Signed informed consent form (ICF) by the participant aged 18 years or older or by a legal major representative and the participant
• Willingness to deliver in one of the two maternities in the study area
• Willingness and ability to comply with study protocol for the duration of the trial
• Willingness to give blood for the examinations and to provide samples for helminth assessment (stool, urine, blood)

Exclusion Criteria:

• Known chronic diseases (diabetes, TB, HIV, HCV or HBV infection); these will be assessed on a regular basis at given examinations during pregnancy
• Withdrawal of consent
• Poor general health (including a hemoglobin level out of local reference range)
• Signs of symptoms of helminth infection which needs immediate treatment of the mother
• Planned migration from the area