Deadly Leptospirosis Bacteria Found in Hawaii Floodwaters After Kona Low Storms

Health officials in Hawaii have issued urgent warnings about a deadly bacteria lurking in floodwaters following the recent "Kona low" storms. The Hawaii Department of Health (DOH) and the Hawaiian Humane Society (HHS) are urging residents and recovery workers to remain vigilant for signs of leptospirosis, a rare but potentially fatal illness. The storms, which dumped over two trillion gallons of rain across the state—equivalent to filling three million Olympic-sized swimming pools—have created conditions that allow the Leptospira bacteria to thrive. This surge in flooding has not only caused widespread damage but also left behind a hidden threat to public health.

The bacteria spreads through the urine of infected animals and can survive in water or soil for weeks or months. During heavy flooding, contaminated soil or water can enter the body through the nose, mouth, eyes, or breaks in the skin. Once inside, the bacterium travels to the bloodstream and attacks vital organs, causing symptoms such as trouble breathing, coughing up blood, and blood in the urine. If left untreated, severe cases can lead to liver and kidney failure, respiratory distress, and brain swelling. In the most extreme cases, severe pulmonary hemorrhagic syndrome (SPHS) may develop, resulting in massive bleeding into the lungs.

Experts emphasize that while leptospirosis is rare in the general population, the risk increases in temporary shelters or areas with rodent infestations. Hawaii already has among the highest rates of leptospirosis in the U.S. due to its warm, wet climate, and the recent storms have exacerbated exposure risks. The DOH and HHS warn that flooding events like the Kona low storm can spread contaminated soil and water over large areas, significantly increasing the chance of infection.

Each year, about 100 to 200 cases of human leptospirosis are reported in the U.S., with half of those cases occurring in Hawaii. Sporadic cases also appear in Puerto Rico, California, and Illinois. The disease primarily affects individuals with recreational exposure to soil and water, such as farmers, veterinarians, and those participating in water sports. In humans, the illness occurs in two phases: the acute leptospiremic phase and the delayed immune phase. During the first phase, symptoms may be mild or absent, but as the bacteria spreads through the bloodstream, more severe signs like vomiting, fever, and diarrhea can develop. These symptoms typically appear within two to 14 days of infection and last three to 10 days.

In the immune phase, the bacteria move from the blood to the organs, which can lead to Weil's syndrome—a rare but life-threatening condition characterized by internal bleeding and organ failure. In pets, leptospirosis manifests as fever, lethargy, vomiting, diarrhea, and jaundice. Dr. Lisa Labrecque, Chief Veterinarian at the Hawaiian Humane Society, highlighted the risks to both humans and animals, noting that many families and their pets endured the same harsh conditions during the storm. She urged pet owners to monitor their animals closely and seek veterinary care immediately if symptoms arise.

Public health advisories stress the importance of avoiding contact with floodwaters and taking preventive measures such as wearing protective clothing and ensuring proper sanitation. Officials are also working to educate communities about the dangers of leptospirosis and the steps they can take to reduce their risk. As recovery efforts continue, the focus remains on protecting public health and preventing further outbreaks.

Early treatment with antibiotics is effective, but this disease can progress quickly and become life-threatening if left untreated. The window for intervention is narrow, and delays can lead to irreversible organ damage or death. Health officials are urging vigilance as cases surge in regions where flooding has created ideal conditions for the bacteria to thrive.

Leptospirosis can be managed in both pets and humans with antibiotics, though the disease's rapid progression demands swift action. In humans, symptoms often mimic flu-like illness at first, but without timely care, the infection can spiral into severe complications, including kidney failure, liver damage, and hemorrhaging. For pets, especially dogs, the stakes are equally high—untreated infections can lead to chronic illness or fatality.

There are no vaccines available for humans, though a two-dose shot exists for dogs, offering a critical layer of protection in communities where the disease is endemic. This gap in human immunization underscores the urgency of early detection and treatment. Dr. Ariella Barry, an epidemiology expert with the DOH Disease Investigation Branch, emphasized that pets often serve as the first line of warning. "After a flooding event like this one, the risk is very real," she told the *Honolulu Star-Advertiser*. "Pets are often the first indicator that leptospirosis is circulating in a community."

The connection between flooding and outbreaks is no coincidence. Contaminated water from overflowed sewers or stagnant pools becomes a breeding ground for the bacteria, which can enter the body through open wounds or mucous membranes. Dogs, which frequently wade through such environments, are particularly vulnerable. Their infections not only threaten their own health but also signal a potential hazard for humans sharing the same space.

Health departments are scrambling to raise awareness, urging residents to seek medical attention immediately if they exhibit symptoms like fever, muscle aches, or jaundice. For pet owners, prompt veterinary care is equally vital. The message is clear: time is the enemy in the fight against leptospirosis, and every hour lost increases the risk of irreversible harm.