South Region Illness Concerns

Page originally published 02/16/2024. Last updated 07/16/2024.


The Public Health Services (PHS) department, in the County of San Diego Health and Human Services Agency, takes every report of illness seriously. This webpage provides information on the ongoing surveillance and investigation of gastrointestinal illness (GI) concerns in the South Bay Region.  


See below, or click the following links, to learn more about:


  • On September 27, 2023, PHS was alerted about a possible increase in “gastrointestinal (GI) illnesses” being seen by a local South Bay urgent care practice
  • Since being alerted, PHS has:
    • Reviewed San Diego County data and regional data for trends in GI illnesses.
    • Reviewed GI illnesses data from two additional clinics in the same geographic area.
    • Placed PHS staff in the urgent care facility to collect and review client data related to potential sewage spill related illnesses.
    • Met with local agencies, including the Department of Environmental Health and Quality (DEHQ) and Air Pollution Control District (APCD).
    • Met with state agencies, including the State Public Health Officer, California Department of Public Health (CDPH); Environmental Protection Agency (EPA); and the Coastal Commission about the local concerns raised.  

To date, data analysis shows that there have been no significant increases in reportable GI illnesses in the South Bay Region. The surveillance and investigation are ongoing. PHS will continue efforts to determine public health risks to keep San Diegans healthy, safe, and thriving. 

Understanding Gastrointestinal Illnesses

Germs and chemicals can be found in water we swim or play in, including swimming pools, water parks, hot tubs, lakes, rivers, flood waters, or oceans. You can get GI illnesses, such as diarrhea only if you swallow or ingest water infected with germs.

Other conditions associated with external exposure to contaminated waters include skin rashesear paincough or congestion, and eye pain.


What are the symptoms of GI illnesses?

  • The main symptoms are watery diarrhea and vomiting.
  • A person who is sick may also have headache, fever, muscle aches, and stomachache (abdominal cramps).
  • Symptoms usually begin 1 to 2 days after infection, and lasts for 1 to 10 days, depending on which virus causes the illness.

Is GI illness serious?

  • People who get diarrhea and/or vomiting almost always recover completely without medical treatment with no long-term health problems.
  • However, diarrhea and/or vomiting can cause dehydration and a loss of minerals (e.g., salt and potassium) if people who are sick are unable to drink enough fluids to replace what they lose through diarrhea or vomiting.
    • Infants, young children, persons who are unable to care for themselves (such as the disabled or elderly), and persons with a weakened immune system are at risk for dehydration from loss of fluids.
    • Some people may need to be treated at a medical center or hospitalized to correct or prevent dehydration and/or loss of minerals (e.g., salt and potassium).

What should you do if you get sick?

  • Drink plenty of fluids
  • Wash hands with soap and water often for 15-20
    seconds, or use an alcohol hand gel, if soap and water are unavailable.
  • Clean up spills of stool and vomit quickly using
    a disinfectant.
  • Do not help prepare or serve food.
  • If you have symptoms that are severe or
    concerning to you, please call your healthcare provider, so a stool sample can
    be collected for testing. If you do not have a healthcare provider, call 2-1-1.

How can I prevent getting sick?

Take a few simple steps when you visit oceans, lakes, rivers, and other bodies of water to protect yourself and others.


Know before you go:    

  • Check online to find out if the area is monitored, under advisory, or has been closed for health or safety reasons. This is especially important after a heavy rain.
  • If your body’s ability to fight germs is already affected by other health problems or medicines, check with your healthcare provider before swimming in oceans, lakes, rivers, and other bodies of water.

Stay out of the water if:

  • Signs say the area is closed. This may be due to high levels of germs in the water which make it unsafe for swimming.
  • The water looks cloudier than usual, is discolored, or smells bad.
  • You see any pipes draining into or around the water.
  • You are sick with diarrhea. Germs in diarrhea can get in the water and make others sick if they swallow the contaminated water.
  • You have an open cut or wound. Germs in the water can get into open cuts or wounds and cause infections.

Once you are in the area:

  • Do not swallow the water. Water can contain germs that can make you sick if swallowed.
  • Keep sand away from your mouth and children’s mouths. Sand can contain germs that can make you sick if swallowed.
  • Wash your hands for 20 seconds before eating food, especially if you have been playing in or touching sand. If soap and water are not available, use an alcohol-based sanitizer that contains at least 60% alcohol.
  • Do not swim, go into, or swallow contaminated water sources.

Stay out floodwater.

  • Floodwaters can contain many things, such as downed power lines; human, livestock, and industrial hazardous waste; and other germs that may harm health.
  • External exposure may cause wound infections, skin rash, and tetanus.
  • Internal exposure (i.e., swallowing, eating contaminated foods) may cause GI illnesses.
  • If you must enter floodwater, wear rubber boots, rubber gloves, and goggles.
  • If you come into contact with floodwater, wash the area with soap and clean water as soon as possible, and wash contaminated clothes before reusing.

Surveillance Data

PHS routinely monitors disease trends across the county.

  • Data sources include syndromic surveillance data from emergency departments and communicable disease reports from health care providers and laboratories.
  • Syndromic surveillance tracks symptoms, including gastrointestinal (GI) symptoms of patients seen in emergency departments before a diagnosis is confirmed. This allows public health officials to track health concerns in a timely manner.   
  • Title 17 of the California Code of Regulations requires that over 80 diseases and conditions are reported to local health authorities. This includes numerous diseases that cause diarrhea or other GI illness symptoms. Health care providers and laboratories report positive test results for these diseases to the County of San Diego for additional follow up and public health action. 

Surveillance Bulletin: South Region Gastrointestinal Illness

  • This report shows recent trends of GI illness for residents of South Region
  • Syndromic data will be updated weekly.