Risk of attack in leprosy in relation to age at exposure

ABSTRACT

A study of the life experience of 1520 individuals living in the province of Cebu, P. I., and exposed in the household to lepromatous leprosy reveals the following facts 1- There is a clear relationship between age at the time of exposure and the risk of developing lepromatous leprosy. It is highest for those exposed before the age of 5 years, decreasing progressively as the age at time of exposure increases. This is true for both males and females. 2- The ratio of the incidence rates for males to those for females, for those exposed before 5 years of age, varies from 4.71 for rates in the age band of 5 to 10 years to 1.41 for those of 20 years and over. 3- The average interval between exposure and development of lepromatous leprosy was 10.5 years for those exposed under 10 years of age but only 6.0 years for those exposed after the age of 10 years.