Background: An essential part of the progress towards the global eradication of poliomyelitis is the ongoing evaluation of populations immunity. Migration of unregistered individuals poses a challenge to such estimations. Moreover, partially immunized immigrants might enlarge immunity gaps and facilitate polio outbreaks in their destination countries.
Objectives: To study the level of immunity to polio in adult foreign workers in Israel.
Methods: Foreign workers (n = 145) from the Philippines, India, and Western Africa were tested for neutralizing antibodies against three IPV strains and an outbreak-associated wild virus. Demographic and immunization data were collected by questionnaires.
Results: Seropositivity rates and geometric mean titers (GMTs) for the Mahoney (type 1), MEF (type 2), and Saukett (type 3) poliovirus strains and the wild poliovirus type 1 strain were 99.3% (GMT--233.8), 98.6% (GMT--268.5), 99.3% (GMT--89.4), and 99.3% (GMT--139.5), respectively. Higher GMTs were associated with parenthood and older age. African individuals had significantly higher GMTs for the Saukett strain, compared with individuals from the Philippines and India.
Conclusions: Our results indicate a high level of immunity among foreign workers. More serosurveys are indicated in the future in order to monitor the level of immunity in residents in Israel.