Germs: Protect against bacteria, viruses and infections
Mar 5, 2024 · Many disease-causing bacteria make powerful chemicals called toxins that damage cells and make you ill. Other bacteria can get into and damage tissues. Some infections …
Urinary tract infection (UTI) - Symptoms and causes - Mayo Clinic
When that happens, bacteria may take hold and grow into a full-blown infection in the urinary tract. The most common UTIs affect the bladder and urethra. Infection of the bladder. Bacteria …
Helicobacter pylori (H. pylori) infection - Symptoms & causes
Dec 16, 2025 · A Helicobacter pylori infection is a common stomach infection. It's caused by a germ called Helicobacter pylori, a bacteria also known as H. pylori. More than half the people …
Bacterial vs. viral infections: How do they differ? - Mayo Clinic
Nov 25, 2025 · Bacteria cause bacterial infections. Viruses cause viral infections. Antibiotic medicines kill or keep many bacteria from growing but don't treat viruses. Antiviral medicines …
Bacterial vaginosis - Symptoms and causes - Mayo Clinic
Jun 10, 2023 · Bacterial vaginosis can happen at any age. But it's most common during the reproductive years. The changes in hormones during this time make it easier for certain kinds …
Cystitis - Symptoms and causes - Mayo Clinic
Apr 29, 2025 · Cystitis is a condition that affects the bladder. It happens most often when bacteria cause an infection. But there are other causes, too.
Legionnaires' disease - Symptoms & causes - Mayo Clinic
Dec 22, 2025 · Legionnaires' disease is a severe form of a lung infection called pneumonia. It's caused by a bacterium known as legionella. Most people who catch Legionnaires' disease …
Small intestinal bacterial overgrowth (SIBO) - Mayo Clinic
Nov 11, 2024 · Small intestinal bacterial overgrowth (SIBO) occurs when there is an abnormal increase in the overall bacterial population in the small intestine — particularly types of …
Meningitis - Symptoms and causes - Mayo Clinic
Oct 17, 2024 · Several strains of bacteria can cause bacterial meningitis. The most common are: Streptococcus pneumoniae. This germ is the most common cause of bacterial meningitis in …
E. coli - Symptoms and causes - Mayo Clinic
Oct 1, 2022 · Most strains of E. coli bacteria are harmless, but some can cause severe symptoms. Learn about symptoms and treatment of this common foodborne illness.