Abstract

Poliomyelitis is a life-threatening acute paralytic disease caused by Poliovirus (PV). In the present study, the immunostatus of polio-vaccinated children and young adults (1 to 21 years old) living in Jeddah, Saudi Arabia was investigated to ascertain their extent of protection against the virus. Children were categorized in three groups: (A) Immunocompetent: Group I: Vaccinated by IPV at first and, Group II- Vaccinated by OPV at first; (B) Immunocompromised: Tuberculosis (T.B), diabetes, AIDS, congenital immunodeficiency; and (C) Control group: healthy children vaccinated at a private hospital in Jeddah- IMC hospital. Blood samples (692) were collected from the children admitted to Hospital children wards of King Abdulaziz University Hospital-KAUH (Government), and International Medical Center Hospital-IMC (Private) in Jeddah City, for routine medical examination checkup, during a 24-month period, from January 2015 to December 2016. A total of 228 (32.95%) were Saudis and 464 (67.05%) were non-Saudi individuals. The number of samples found to be negative for polio immunoglobulin G (IgG) and were considered as non-immune children was 72 (10.4%) while the overall immune responders were 584 (84.4%). 36 (5.2%) were low positive and their immunity against polio infection was doubtful. Non-Saudi seronegative subjects varied from 28 (6.03%) Yemani, 24 (5.17%) Somalian, 8 (1.72%) Afghani, 4 (0.86%) Indians, 3 (0.65%) Chadian, 2 (0.43%) Pakistanis; to 2 (0.43%) Nigerians. Based on the present data, we recommend higher vaccination coverage and sensitive surveillance investigation in polio-free countries. Evaluation of vaccination programmes should be carried out for the early detection of immune negative and disease-susceptible individuals.

Key words: Poliomyelitis, poliovirus vaccination, seronegative, immunization, immune response.