Apr 8, 2025 · Bacteria, viruses, fungi and parasites are examples of organisms that can cause illness. Many organisms live in and on our bodies. They're too small to see with the eyes. And they're often …

Mar 5, 2024 · Viruses are responsible for causing many diseases, including: Common cold. Influenza. Measles. Chickenpox and shingles. Coronavirus disease 2019, also called COVID-19. Antibiotics kill …

Nov 25, 2025 · Viruses that become resistant to antivirals have affected treatment, including for genital herpes, HIV and, in 2008, for influenza (flu). Treating and preventing bacterial and viral infections In …

Dec 19, 2025 · Influenza viruses are constantly changing, with new strains appearing often. A person's first flu infection gives some long-term protection against similar strains of flu. But the vaccines …

Oct 21, 2025 · Viruses cause both COVID-19 and the flu. COVID-19 is caused by SARS-CoV-2, also known as severe acute respiratory syndrome coronavirus 2. The flu is caused by influenza viruses.

3 days ago · Coronavirus disease 2019 (COVID-19) is an illness caused by the virus SARS-CoV-2. Learn more about the symptoms, risks and ways to protect yourself.

Oct 4, 2023 · Respiratory syncytial virus (RSV) causes infections of the lungs and respiratory tract. It's so common that most children have been infected with the virus by age 2. Respiratory syncytial (sin …

Explore comprehensive guides on hundreds of common and rare diseases and conditions from the experts at Mayo Clinic.

Mar 15, 2024 · Viruses that have been linked to Bell's palsy include viruses that cause: Cold sores and genital herpes, also known as herpes simplex. Chickenpox and shingles, also known as herpes …

Jan 18, 2025 · Causes A number of diseases and conditions can cause diarrhea, including: Viruses. Viruses that can cause diarrhea include Norwalk virus, also known as norovirus, enteric …