PREVALENCE OF MEASLES VIRUS INFECTION AMONG VACCINATED AND NON-VACCINATED CHILDREN IN NORTHERN INDIA

Introduction: Measles virus (MeV) is still a common acute illness caused by viruses belonging to the family Paramyxoviridae and genus Morbillivirus. The objective of this study was to determine the prevalence of MeV in both vaccinated and unvaccinated children and consecutively, testing the efficacy of MeV vaccination among children in north India. Materials and Methods: A total of 323 blood samples were collected along with measles mumps rubella (MMR) vaccination history from children (0-15 years) manifesting fever and rashes. In serum samples, we employed the enzyme-linked immunosorbent assay (ELISA) to quantify the presence of IgM antibodies against measles virus infection. Results: Out of 323 serum samples 148 (45.8%) were found to be positive for MeV infections. Expectedly, In the vaccinated group we found the prevalence of MeV is 70 (47.3%), while in unvaccinated children occurrence of MeV infection is 78 (52.7%), showing a statistical significance between vaccination history and measles infection (P<0.0001*). In this study, 0-5 years old children have 93 (62.8%) MeV infection conversely, >5 years old age of children have 55 (37.2%) MeV infection. Conclusion: The children, who have not achieved the MMR vaccine for the elimination of MeV infection and we found 47.3% of children are still being infected with MeV that have MMR vaccination history. Therefore, there is a need to identify the reason for the low protective efficacy of the vaccine as well as long-term follow-up studies are needed for getting insight to longevity and persistence of immunity induced by this vaccine.