6.6—Mycobacterium tuberculosis and HIV infection

Mycobacterium tuberculosis is a bacterium transmitted in airborne droplets; HIV is an enveloped RNA retrovirus transmitted through infected body fluids. Disease outcome depends on entry route, pathogen biology and the host immune state.

TB can remain dormant inside tubercles and reactivate when immunity is weakened. HIV targets immune cells and progressively reduces immune defence, increasing susceptibility to opportunistic infections.

Overcrowding increases TB transmission through inhaled droplets, while sharing contaminated needles can transmit HIV. The prevention strategy must match the route rather than treat “infection” as one mechanism.

Infection is not identical to immediate disease, and an HIV-positive person is not defined by one opportunistic illness. State the pathogen, route and immune consequence.