CD4 and tuberculosis: For example, in a recent study conducted by the OHARA/ACTG group, we found a strong association between OC and TB disease, independent of CD4+ cell count, suggesting that in resource-limited settings, OC may provide clinical evidence for increased risk of TB and contribute to TB case finding.[26] In this context it is necessary that OC be measured accurately by non-OHS such as nurses, as they are the health care providers most frequently involved with the care and screening of HIV-infected patients.