Secondary bacterial infections occur when a person, already weakened by a primary illness, such as a viral infection, is subsequently infected by bacteria. These infections can complicate the course of the initial disease, leading to more severe symptoms, prolonged recovery, and, in some cases, serious health complications. Common examples include pneumonia following the flu, skin infections after chickenpox, or bacterial superinfections during or after a COVID-19 infection. The body’s immune system, compromised by fighting the primary illness, becomes more susceptible to bacterial invaders that would otherwise be controlled. Treatment often requires antibiotics, but the increasing issue of antibiotic resistance complicates management. Preventive measures like vaccination and good hygiene are critical to reducing the risk of secondary bacterial infections.