Infekcie

Infections are diseases caused by microorganisms that invade the body. The agents include bacteria, viruses, fungi, and parasites. Infections can be localized, affecting a specific organ, or systemic, influencing multiple organ systems. The severity is influenced by the pathogen's characteristics and the host's immune status.

Pathogens can spread through direct contact, droplets from coughing or sneezing, airborne transmission, contaminated surfaces, vectors such as mosquitoes, contaminated food or water, and, for some infections, sexual contact. Risk factors include age, chronic diseases, malnutrition, pregnancy, and exposure in crowded or healthcare settings.

Common types include bacterial infections (pneumonia, throat infections), viral infections (influenza, SARS-CoV-2), fungal infections (candidiasis, dermatophyte infections), and parasitic infections (malaria, schistosomiasis). Infections may be acute, resolving in days to weeks, or chronic, persisting longer.

Diagnosis relies on medical history and examination, supported by laboratory tests such as cultures, polymerase chain reaction (PCR), antigen or antibody tests, and imaging studies when needed.

Treatment depends on the causative pathogen. Bacterial infections are treated with antibiotics; many viral infections are managed with supportive care, though some have antiviral medicines; fungal infections use antifungals, and parasitic infections may require antiparasitic drugs. Appropriate therapy reduces illness duration and prevents complications. Antibiotic resistance is a global concern and highlights the need for stewardship.

Prevention includes vaccination, good hand hygiene, safe food preparation, clean water and sanitation, vector control, safe sex practices, and infection control measures in health facilities. Public health strategies track infections to guide policy and protect communities.