Many natural swimming places are currently struggling with blue-green algae. Blue-green algae cause a lot of nuisance for swimmers and recreationists every year. Blue-green algae is poisonous to humans. Stagnant, nutrient-rich water in particular attracts blue-green algae. If blue-green algae is found, a negative swimming advice is given. Rijkswaterstaat and the water boards advise swimming only at official swimming locations where the water quality is good enough. Due to the prolonged drought and heat, the water quality deteriorates in some places; especially in still small waters.
The advice is to only take a refreshing dip at officially designated swimming water locations. This advice applies to both humans and any permitted animals. Blue-green algae, less known as cyanobacteria, are bacteria that look like algae. You see green or blue strands or slimy wads floating on the water.
Symptoms of the infection of blue-green algae
Blue-green algae poisoning only occurs through the mouth, the poison does not penetrate the skin. Blue-green algae can form a floating layer and produce toxic substances. Swimmers and water sports enthusiasts can get sick when they get water, but skin complaints can also arise. Dogs are also sensitive to it. If a floating layer starts to rot, this can cause odor nuisance.
Symptoms
Within 12 hours of swimming in blue-green algae water, you may experience skin irritation, eye irritation, headache, nausea, vomiting, diarrhea, fever, stomach cramps, sore or red throat, earache, runny nose, swollen lips. These symptoms last for about five days and then disappear. If you have complaints, contact your doctor, because the symptoms can also have a cause other than blue-green algae.
Blue-green algae on highly diluted hydrogen peroxide have been successfully controlled in several places in the Netherlands. The pee is closed during the treatment and the day after. Swimming is then not allowed.
No health risk
The concentration of hydrogen peroxide added to the pee is so low that there is no risk to human and animal health.
Weil’s disease
Weil’s disease is transmitted to humans through the urine of infected dogs, pigs or rats. The bacteria penetrate through the mucous membranes or through the skin, especially at skin wounds.
Symptoms
Five to ten days after infection, it begins with the acute development of chills, fever, muscle pain (usually in the calves), headache, nausea, vomiting and a drop in blood pressure. Jaundice due to liver damage occurs about four days after the first symptoms appear. Bleeding may arise from the mucous membranes of the nose, mouth and eyes, and the urine may also contain blood.
In case of infection with Weil’s disease, one must be admitted to hospital. Adequate treatment is of vital importance. Most people are cured, but the disease can lead to death. Treatment consists of administering medication and sometimes kidney dialysis is (temporarily) required. Always go to a doctor or general practitioner immediately if you suspect that you have Weil’s disease to limit serious liver and kidney damage.
Botulism
Botulism is poisoning caused by the bacteria clostridinum botulinum. The bacteria thrives best in water that is twenty degrees Celsius or warmer. The disease mainly occurs in waterfowl and fish. They develop paralysis and eventually die.
Symptoms
In humans, the symptoms are nausea and vomiting, then poor vision, difficulty speaking and swallowing, listlessness, nausea, vomiting, the muscles weaker. Contamination in humans is uncommon.
In case of botulism infection, an antiserum must be given. Sometimes temporary ventilation is required. Without treatment, the person can die from paralysis of the respiratory muscles.
All designated bathing water locations are monitored by Rijkswaterstaat, water boards and Provinces and can be found at www.zwemwater.nl. Here you will also find information about the current bathing water quality.
Please note, swimming in surface water is always at your own risk.
–
