The interpretation is further supported by our previously-published work, where TB patients were found to have higher levels of IL-4 than healthy community controls from the same region of Ethiopia [15] but not contacts, and more recent findings that elevated expression of IL-4 among TB contacts in this area correlates with the magnitude of their recognition of ESAT-6 (a proxy marker for the severity of infection [14], [18]. This evidence concerns the gene IL4 and tuberculosis.