HIV symptoms vary by the stage of infection, known as acute HIV infection (Stage 1), chronic HIV infection (Stage 2), and AIDS (Stage 3). During primary infection, the symptoms are caused by the virus ...

Many people with tuberculosis stay in the latent infection stage, but some develop the active disease. Both stages are treatable. Tuberculosis (TB) is a bacterial infection that usually affects the ...

Syphilis is a sexually transmitted infection. Without treatment, the stages of syphilis include symptoms that worsen over time. They can lead to severe or possibly fatal complications. Syphilis is a ...