Journal Article

The impact of prenatal exposure to parasitic infections and to anthelminthic treatment on antibody responses to routine immunisations given in infancy: Secondary analysis of a randomised controlled trial

Mentzer, Alexander J., Nash, Stephen, Lule, Swaib A., Smits, Gaby, Kizito, Dennison, Elliott, Alison M., van der Klis, Fiona R. M.

2017

Overview

Chronic parasitic infections are associated with active immunomodulation which may include by-stander effects on unrelated antigens. It has been suggested that pre-natal exposure to parasitic infections in the mother impacts immunological development in the fetus and hence the offspring's response to vaccines, and that control of parasitic infection among pregnant women will therefore be beneficial. We used new data from the Entebbe Mother and Baby Study, a trial of anthelminthic treatment during pregnancy conducted in Uganda, to further investigate this hypothesis. 2705 mothers were investigated for parasitic infections and then randomised to albendazole (400mg) versus placebo and praziquantel (40mg/kg) during pregnancy in a factorial design. All mothers received sulfadoxine/pyrimethamine for presumptive treatment of malaria. Offspring received Expanded Programme on Immunisation vaccines at birth, six, 10 and 14 weeks. New data on antibody levels to diphtheria toxin, three pertussis antigens, Haemophilus influenzae type B (HiB) and Hepatitis B, measured at one year (April 2004 -May 2007) from 1379 infants were analysed for this report. Additional observational analyses relating maternal infections to infant vaccine responses were also conducted. Helminth infections were highly prevalent amongst mothers (hookworm 43.1%, Mansonella 20.9%, Schistosoma mansoni 17.3%, Strongyloides 11.7%, Trichuris 8.1%) and 9.4% had malaria at enrolment. In the trial analysis we found no overall effect of either anthelminthic intervention on the measured infant vaccine responses. In observational analyses, no species was associated with suppressed responses. Strongyloidiasis was associated with enhanced responses to pertussis toxin, HiB and Hep B vaccine antigens. Our results do not support the hypothesis that routine anthelminthic treatment during pregnancy has a benefit for the infant's vaccine response, or that maternal helminth infection has a net suppressive effect on the offspring's response to vaccines. ISRCTN.com ISRCTN32849447.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Adult / Albendazole - administration & dosage / Analysis / Animals / Anthelmintics / Anthelmintics - administration & dosage / Antibodies, Helminth - immunology / Antibody Formation / Antigens / Babies / Biology and Life Sciences / Drug therapy / Female / Fetuses / Funding / Health aspects / Helminthiasis - drug therapy / Helminthiasis - embryology / Helminthiasis - epidemiology / Helminthiasis - immunology / Helminths - genetics / Helminths - immunology / Hepatitis / Humans / Hypotheses / Immune response / Immunization / Immunology / Infant / Infant care / Infant, Newborn / Infant, Newborn, Diseases - immunology / Infant, Newborn, Diseases - prevention & control / Infants / Infections / Influence / Malaria / Male / Medicine and Health Sciences / Mothers / Offspring / Parasites / People and Places / Physiological aspects / Praziquantel - administration & dosage / Pregnancy / Pregnancy Complications, Parasitic - drug therapy / Pregnancy Complications, Parasitic - epidemiology / Pregnancy Complications, Parasitic - immunology / Prenatal exposure / Prenatal Exposure Delayed Effects - epidemiology / Prenatal Exposure Delayed Effects - immunology / Prenatal Exposure Delayed Effects - prevention & control / Prenatal influences / Public health / Roundworm infections / Secondary analysis / Studies / Toxins / Tropical diseases / Uganda - epidemiology / Vaccines / Vaccines - administration & dosage / Vaccines - genetics / Vaccines - immunology / Vector-borne diseases / Whooping cough / Young Adult