Immunocompromised hosts, such as individuals undergoing chemotherapy, those with HIV/AIDS, or organ transplant recipients, are particularly vulnerable to infections due to their weakened immune systems. Infectious diseases in immunocompromised hosts can manifest in unusual or severe forms, making diagnosis and treatment more challenging. Opportunistic infections, including fungal, bacterial, and viral pathogens, are common in these patients, and even mild infections can progress rapidly into life-threatening conditions. Effective management requires a careful balance of antimicrobial therapy, immunosuppressive medications, and close monitoring. Additionally, preventative measures, such as vaccinations and hygiene practices, play a critical role in reducing the risk of infections in immunocompromised individuals.