Epidemiologic study of 107 cases of families with leprosy in Duque de Caxias, Rio de Janeiro, Brazil.

Backgrounds: ultibacillary patients are the major source of infection in leprosy. Nevertheless, the risk is higher in household contacts between multibacillary patients than paucibacillary patients and in the general population. Household contacts are in close genetic relationship with the index case-patient.

Objective: To evaluate epidemiological data of the following variables: age, gender, education level, genetic proximity, and type of contact with the index case-patient (household or not) in 107 families with leprosy.

Methods: Home visits were conducted to clinically examine family members. The medical charts of index case-patients and co-prevalent cases were reviewed.

Results: The controlled analysis of variables such as type of contact and genetic proximity revealed that household contacts and first-degree kinship are independently associated with a higher chance of contracting the disease.

Conclusion: Household contacts are often genetically closer to the index case-patient. To investigate the independent relevance of these risks in leprosy surveillance contact studies has been a challenge. Our results confirm literature data that show the influence of genetics in the susceptibility to leprosy per se.