A sero-survey to identify the window of vulnerability to measles in infants in North-Eastern Nigeria

ABSTRACT

As infants lose maternal measles antibodies (MMAs); they experience periods when their antibody levels are insufficient to protect them against measles. A prospective study was carried out at the University of Maiduguri Teaching Hospital. Sera collected from neonates at birth; and at six weeks; three months; six months and nine months of age; were analysed for MMAs by enzyme-linked immunosorbent assay. Seventy-seven neonates were enrolled. Of these; 73 (94.8) had protective MMAs at birth. This figure declined to 36 (46.8); 28 (36.4); 13 (16.9) and 4 (5.2) at six weeks; three months; six months and nine months of age (?2 = 154.264; p-value = 0.000). Protective MMAs at birth waned rapidly; resulting in an early window of vulnerability to measles by the age of six months. Protecting infants with early measles immunisation with potent; safe vaccines are recommended