While Leptospirosis is a bacterial infection that can occurs worldwide, it is more common in tropical and sub-tropical areas. For example, Leptospirosis is a relatively frequent disease in Mexico. In California, Leptospirosis is an emergent disease, which could be explained (at least in part) by our changing climate. Leptospirosis is caused by spiral-shaped bacteria that can cause damage to the liver, kidneys, and other organs of animals and humans. Cases usually occur in the summer and fall; large outbreaks have occurred after flooding. Leptospirosis is not spread from person to person, but from animals to humans through the urine of infected animals, which gets into soil or water. Humans and animals can become infected through direct contact with this contaminated soil or water, where the bacteria can survive for some months. The bacteria can also enter through cuts in the skin, through the mucous membranes or through drinking water.
In cattle, sheep, goats and swine, symptoms of Leptospirosis may include fever and reproductive problems (e.g., abortions). In humans, symptoms can range from mild to severe (including flu-like illness, weakness, vomiting, mental confusion, jaundice, and stiff neck). Most people who become infected have no symptoms or may confuse their symptoms with a simple cold. Unfortunately, some people may develop more significant problems from Leptospirosis.
Vaccines are currently available for livestock and dogs – these vaccines can help prevent disease severity but may not complete prevent infection. We can protect our own health by preventing and controlling infection in our livestock. In addition, rodents can be a reservoir of the disease, so rodent control is important. Don't handle urine, blood, or tissues from infected animals – wear protective clothing, especially gloves! And always wash up after handling animals!
As you might imagine, Leptospirosis is primarily an occupational disease in humans – in other words, those of us who work directly with animals, contaminated soil, or stagnant water can be at greater risk. Half of California cattle herds have been estimated to be infected with Leptospira, which can be a serious threat to livestock producers and ranch employees. Active epidemiological surveillance has been repeatedly recommended, but surprisingly, no studies on Leptospirosis have been conducted in California agriculture workers. As a result, the Center for Health and the Environment at UC Davis is studying the prevalence of the disease in farmers and ranchers, farm workers, and veterinarians. This study will help researchers better understand the main exposure factors. The Center is looking for volunteers to participate in the study.
You can participate if you are:
- At least 18 years old;
- A rancher, ranch worker, or veterinarian; or
- Working in agriculture, or in close contact with livestock.
You must not have been sick during the last five weeks.
If you decide to participate in the study, researchers will ask some questions about your occupation and work history. You will also be asked to provide a blood sample. The questionnaire and the blood draw will take about 30 minutes. After you have answered the questions and a professional has taken your blood sample in a health facility, you will receive $60 in compensation. The survey and blood collection are completely anonymous.
If you are interested in participating or want more information (in English or Spanish), contact:
Center for Health and the Environment – UC Davis
Alvaro Medel
(530) 761-6380