County of Los Angeles Public Health (May 5, 2025) Hepatitis A is a contagious liver infection caused by the hepatitis A virus (HAV). It is one of the most common forms of hepatitis worldwide. The infection can range from a mild illness lasting a few weeks to a severe illness lasting several months, and in rare cases, it can be fatal.  Viral Hepatitis | ACDC | LACDPH (lacounty.gov)

Center of Disease Control (CDC) (May 22, 2025) Norovirus is a very contagious virus that causes vomiting and diarrhea. It is sometimes called the "stomach flu" or the "stomach bug." However, norovirus illness is not related to the flu. The flu is caused by the influenza virus. Norovirus causes acute gastroenteritis, an inflammation of the stomach or intestines. Most people with norovirus illness get better within 1 to 3 days; but they can still spread the virus for a few days after. Norovirus Outbreak (CDC)