Two deadly diseases, HIV and TB, can often co-exist in the same patient.

Find out how many lives are affected by TB around the world. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Find out exactly how TB causes damage to the lungs. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.

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