Measles virus-specific antibody levels in Sudanese infants: a prospective study using filter-paper blood samples.
We conducted a prospective birth cohort study in rural Sudan to assess measles virus (MV)-specific antibody levels at different time points in infancy. Dried blood spots were collected on filter paper at birth (cord blood) and at ages 6, 12 and 24 months (heel-prick). Maternally derived MV-specific antibody levels were high in cord blood samples, but at the age of 6 months had dropped below cut-off values in half of the infants. By extrapolation it was concluded that the current Expanded Programme of Immunization (EPI) target age for measles vaccination of 9 months was an appropriate choice for this area. At the age of 24 months acquired MV-specific antibodies were detected in 65-85% of the cohort, which corresponded well with the 79% of infants reported to be vaccinated by this age. This study demonstrates the usefulness of filter paper blood samples for seroepidemiological studies in developing countries.
Ibrahim
S A
SA
Department of Paediatrics, University of Khartoum, Sudan.
Abdallah
A
A
Saleh
E A
EA
Osterhaus
A D M E
AD
De Swart
R L
RL
D000914:Antibodies, Viral / Q000032:analysis*; D001800:Blood Specimen Collection; D005260:Female; D005374:Filtration; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008457:Measles / Q000453:epidemiology*; D008458:Measles Vaccine; D011446:Prospective Studies; D012016:Reference Values; D012424:Rural Population; D016036:Seroepidemiologic Studies; D013048:Specimen Handling; D013397:Sudan / Q000453:epidemiology
D000914:Antibodies, Viral; D008458:Measles Vaccine