Incidence of rubella IgM antibodies in individuals with febrile rash illness attending clinics in Akwa Ibom State, Nigeria, 2006-2009

Abstract

Background: Rubella is an infectious disease of public health importance because infection ac-quired during early pregnancy often results in foetal abnormalities that are classified as con-genital rubella syndrome (CRS). The burden of rubella infection in most developing countries is however not well documented because of lim-ited epidemiological data. Methods: Between 2006 and 2009, 781individuals with febrile rash illness seen in clinics in Akwa Ibom State were screened for rubella specific IgM antibodies using the ELISA technique. Statistical analysis was done using Graph prime version 5.3 statis-tical package at 95% confidence interval. The level of significance was established at P = 0.05 using Fisher’s exact two-tailed values. Results: Of 781 individuals screened for rubella specific IgM antibodies, 94 (12%) were found to be posi-tive. Incidence of 8.7% recorded in 2006 gradu-ally rose to 9.3% in 2007, 11.6% in 2008 and 14.3% in 2009. Those in the reproductive age group (> 16 years) were most affected (51.7%). However, this was not statistically significant (P = 0.228). Females (17.4%) were more suscepti-ble than males (6.2%) (P < 0.0001) an rural dwellers (12.8%) more susceptible than urban dwellers (10.5%) (P = 0.416). Conclusion: The study shows that the incidence of rubella in Akwa Ibom State, Nigeria is high. The lowest incidence was however found among individu-als below the reproductive age. Thus, the find-ings of this study can be used by policy makers to model the introduction of routine rubella vaccination into the country’ Expanded Program on Immunization Schedule (EPI).