What is COVID-19?

​COVID-19 is an infectious disease caused by the SARS-CoV-2 virus. Most people with COVID-19 have mild symptoms, but some people become severely ill. Older adults and people who have certain underlying medical conditions are more likely to get severely ill. Post-COVID conditions can include a wide range of health problems that can last four or more weeks after contracting COVID-19. Even those who do not become severely ill from COVID-19 may experiencepost-COVID conditions, sometimes referred to as Long COVID. For more information, visit the Centers for Disease Control and Prevention’s (CDC) Basics of COVID-19


COVID-19 is spread in three main ways:

  • Breathing in air when close to an infected person who is exhaling small droplets and particles that contain the virus.
  • Having small droplets and particles that contain the virus land on the eyes, nose, or mouth, especially through splashes and sprays like a cough or sneeze.
  • Touching eyes, nose, or mouth with hands that have the virus on them.

People with COVID-19 have reported a wide range of symptoms – ranging from mild symptoms to severe illness. Symptoms may appear 2-14 days after exposure to the virus.


Common COVID-19 symptoms include:

  • Fever or chills
  • Cough
  • Shortness of breath or difficulty breathing
  • Fatigue
  • Muscle or body aches
  • Headache
  • New loss of taste or smell
  • Sore throat
  • Congestion or runny nose
  • Nausea or vomiting
  • Diarrhea

This list does not include all possible symptoms. Symptoms may change with new COVID-19 variants and vary depending on vaccination status. Learn more here about CDC COVID-19 Symptoms


The Maryland Department of Health (MDH) works with partners to monitor the global COVID-19 outbreaks and provide information to residents.