Principal Investigator - Dr. Kathleen Powis, MD, MPH

Study Objectives

Specific Aim 1: Define TB-related and TB-independent risk factors if morbidity and mortality in the first year of life among BCG vaccinated HE and HUU infants enrolled in the Karabo Study and a second ongoing study in Cape Town, South Africa, the InFANT Study (Innate Factors Associated with Nursing Transmission; funded by Canadian Institutes of Health Reseach), using multivariable logistic regression analysis.

• Specific Aim 1A: Quantify differences in prevalence the combined outcome of LTBI between HEU and HUU infants.
• Specific Aim1B: Quantify differences in prevalence in combined outcome of infectious morbidity and mortality between HEU and HUU infants.

Specific Aim 2: Define immune correlates of risk for tuberculosis in HEU infants comparing conventional and unconventional T-cell corralates between HEU infants who develop LTBI in the first year of life to those who do not.

Study Design: The Karabo Study is a Sub-study within the Tshilo Dikotla study that is designed as an observational prospective study to evaluate the prevalence of latent tuberculosis infection and active TB and compare differences in this prevalence by infant HIV exposure status.Foer HIV-exposed uninfected infants who are found to have latent tuberculosis infection or develop active TB, we will conduct a cases control analysis to assess for differences in immune resposes to the BCG vaccine.

Study Population and Size: The Karabo Study is a substudy embedded within the Tshilo Dikotla study. Only 270 mother-infant pairs, of which 184 women are living with HIV and 86 women are HIV-uninfected will be recruited for this study. Women are of childbreaing age and infants of whom approximately 49% are male must be no greater than 14 months of age. Up to 270 mother-infants pairs participating in the Tshilo Dikotla stdy of whom 184 will be women living with HIV and their infants.

Study Duration: 5 years

Sponsor: National Institute of Allergy and Infectious Diseases.