Infectious diseases remain a significant challenge in modern medicine. They are caused by pathogenic microorganisms such as bacteria, viruses, fungi, and parasites. These infections spread through various routes, including person-to-person contact, animal-to-person transmission, or from contaminated environments.

Modern medicine focuses heavily on the prevention, diagnosis, and treatment of infectious diseases. Diagnosis is achieved through various laboratory methods, including the analysis of blood, urine, and other biological fluids, as well as the identification of specific pathogens.

Treatment depends on the causative agent. Antibiotics are used for bacterial infections, antiviral drugs for viral infections, antifungal agents for fungal infections, and antiparasitic drugs for parasitic infections. Some infections, like the common cold, often resolve on their own, but symptomatic treatment may be necessary to alleviate symptoms.