Leptospirosis

As we talk about vector borne diseases, we will shift the focus this week away from mosquitoes and consider another vector borne disease that is of public health concern in St Vincent and the Grenadines and throughout other countries of the Americas.

Leptospirosis is a disease caused by the bacteria Leptospira interrogans that produce a wide range of symptoms. Patients may develop kidney or liver failure, respiratory failure, meningitis, or even death from this disease.{{more}}

The disease is spread by the urine of infected animals (many wild animals, rodents, dogs, cats, pigs, horses, cattle, etc). These animals contaminate water, soil, and crops when they urinate, because the bacteria are present in their urine. The bacteria then infect humans through breaks in the skin or mucus membranes, or when people ingest them by drinking or eating contaminated products. The bacteria can survive in water and soil for months. The disease is most common in temperate and tropical climates. The infecting bacteria occur worldwide.

Risk factors include occupations that expose people to farm animals, wild animals, and to contaminated water and soil. People who participate in outdoor activities, like camping, or persons living and working in the “hills” are also at higher risk for infection. Any exposure to sewage or animal waste increases risk of getting leptospirosis.

Unfortunately, the signs and symptoms of leptospirosis are variable and are similar to those seen in many other diseases. Symptoms can arise about two days to four weeks after exposure to the bacteria. Although some people have no symptoms, others may exhibit one or more of the following: high fever, chills, headache, muscle ache, abdominal pain, vomiting, diarrhoea, jaundice, rash, and reddish eyes. These symptoms usually occur in the first phase of the infection, and when present, they often occur abruptly.

Some patients resolve their symptoms and do not progress to the second phase; others may seem to briefly recover, but relapse with more severe symptoms and organ damage. The second phase of leptospirosis, called Weil’s disease, is severe. If it is not treated, it may not resolve for several months. The death rate is about one to five per cent.

Antibiotics are recommended for treatment of patients with the disease. Some patients may require IV antibiotics and supportive hospital care. Early diagnosis and treatment are key to good results if someone has leptospirosis. Leptospirosis can be avoided. You can protect yourself by avoiding contact with animal excrement, practising good hygiene, and avoiding contaminated water and soil.

Dr Rosmond Adams is a medical doctor and a public health specialist. He may be emailed at adamsrosmond@gmail.com