By: James Peacock

The Nevada County Public Health Department has announced that they are tracking an outbreak of E. coli  infections linked to Wildwood Lake, in Northern California. Several beaches have been closed as a result of the outbreak. Nine children have been sickened over the course of this outbreak, as well as one adult who was described as “closely associated with one of the symptomatic children.” Six of the children who have been sickened have needed to be hospitalized, with two of them being released from the hospital already. There have been three reported cases of hemolytic uremic syndrome, a serious and potentially life-threatening complication.

When the outbreak was first discovered, Commodore Park beach was closed in order to help prevent infection. Test results were received the next day, July 29, and indicated that the beach should remain closed. All ill individuals visited Commodore Park beach prior to becoming sick. Even still, health officials tested samples from all five public beaches along Wildwood Lake. Those results, received on August 1, showed that there were dangerous levels of illness-causing bacteria at three of the beaches—Commodore Park, Meadow Park, and Hideaway Park. Out of an abundance of caution, the health department closed all of the public beaches in order to prevent infection. The beaches will be tested for bacterial contamination twice a week until further notice. The health department is also running other tests in an effort to track down where the E. coli contamination came from. The Public Works Department tested for leaks in the sewer lines by adding a dye to the water. This dye is inert and dissipates with exposure to the sun, but it will also allow for any leaks to be found. That test is still ongoing. The health department has conducted several other tests, but as of yet has been unable to find a specific source of the E. coli contamination. The Nevada County Public Health Department issued an advisory to all local residents to avoid swimming in the lake until the E. coli risk has gone away. The local public pool is still open though, as no illnesses or contaminations have been linked to it.

What is E. coli?

E. coli bacteria are one of the most common causes of foodborne illness and foodborne illness outbreaks in the United States. While there are quite a few different types of E. coli in the world, there are only a few strains cause illness in humans. Sometimes, these strains of E. coli are one of the several varieties that can produce Shiga toxins. E. coli that produce this toxin are commonly referred to as Shiga toxin-producing E. coli (STEC). There are around 265,000 cases of E. coli poisoning each year in the United States, according to the CDC, though this estimate varies from year to year because in some instance someone with E. coli poisoning may not need medical care. Cases of E. coli poisoning can occur even if only a small amount of bacteria is consumed. Because E. coli can be found throughout the natural world, it has caused foodborne illness outbreaks through a wide variety of different food and drink items. E. coli outbreaks have been caused by beef products, yogurt, cheeses, unpasteurized fruit juices, bagged lettuce, mayonnaise, alfalfa sprouts, spinach, raw milk, various water sources, and more.

E. coli infections and outbreaks have been steadily on the rise since 2009, reaching an incidence rate of 2.85 cases per 100,000 individuals in 2016. This is the highest that the incidence rate has been since 1996. Again, after exposure to even a small amount of bacteria, it is possible for an infection to develop. Symptoms of the infection will typically occur between 3 and 4 days after exposure, but E. coli infections can begin to cause symptoms anywhere between 1 and 9 days after exposure to the bacteria. Symptoms of an E. coli infection will typically include severe cramping, vomiting, nausea, and watery or bloody diarrhea. In some instances, a fever may also present with E. coli infection symptoms. These symptoms, in many cases, will go away on their own after about a week. There is a chance that the infection lasts longer, though. Diarrhea can cause dehydration, a potentially serious complication, so it is important that those suffering from an E. coli infection attempt to stay well hydrated. E. coli bacteria are particularly dangerous for two reasons. First, it seems to target children at a much higher rate than other age groups. In fact, according to the CDC, the incidence rate of E. coli poisoning in children under five is more than double the next closest age group, which is children age 5 to 9. Young children under five have an incidence rate of 7.86 cases per 100,000 people. This is almost triple the overall average incidence rate. This has led health officials to declare that the elderly, along with children and those with suppressed or otherwise compromised immune systems are at an increased risk of developing a serious E. coli infection.

The other major issue is that STEC are able to cause a very serious side effect known as hemolytic uremic syndrome (HUS). Hemolytic uremic syndrome occurs in between 3 and 7 percent of E. coli infections. HUS causes damage to red blood cells, which are then sent to the kidneys in order to be filtered out of the bloodstream. Removing these damaged blood cells can damage the kidneys and clog the mechanisms responsible for removing the afflicted blood cells. The damage done to the filtration mechanisms, coupled with the increased rate of damage inflicted on the kidneys by Shiga toxins, can lead to serious kidney damage and even kidney failure. HUS can also damage the nervous system and other organs in the body, making it especially dangerous. If a case of E. coli poisoning has progressed to HUS, symptoms such as decreased frequency in urination, fatigue, and loss of color in the eyes and cheeks will be present. If you or a loved one begins to show the symptoms of E. coli poisoning, contact a medical professional