Leptospirosis looks to be a growing cause for concern according to researchers.
Researchers have warned that the appearance of new sub-types of the Leptospira borgpetersenii bacteria, together with climate change, will lead to disease outbreaks becoming more common in Australia. Not only will they become more frequent, but they will spread into areas not previously associated with the disease. Rural areas of Australia are particularly at risk.
Leptospirosis is a bacterial disease spread through contact with the urine and faeces of infected animals and in particular through contact with contaminated soil. Not only can humans contract the disease through direct contact with animals, but they can also pick up the bacteria by swimming in freshwater, flood water, and even though gardening. Rodents are a known carrier but in rural areas, livestock and native animals can easily get infected and greatly aid in the spread of the bacteria. The bacteria can remain active for several months in wet and warm soil – which is why there is concern that increasing rainfall and temperatures will increase the spread and incidence of leptospirosis.
The scale of the leptospirosis problem is not well understood in that there is little monitoring for the disease or assessment of the level of incidence. A key challenge is that many victims are either asymptomatic or show symptoms similar to flu or Covid – fever, muscle aches and headaches. Only around 10% of the infected population will progress to severe symptoms including organ failure, meningitis, respiratory distress and in worst-case scenarios, death. In non-lethal cases, full recovery often takes several months.
Globally it is estimated there are about one million cases a year, resulting in around 60,000 deaths. Although cattle are routinely vaccinated for leptospirosis, no human vaccine is available. Successful treatment relies on early diagnosis and use of specific antibiotics. Preventive measures remain the best course of action – this means the wearing of gloves whilst farming, not exposing cuts or open sores to potentially infected water and soil, and having active rodent management programs around rural properties.
Whilst the improved personal safety instructions following the updated rodenticide regulations will also help reduce potential exposure, the restrictions around rodenticide use may impact the level of rodent control in rural areas, therefore increasing the spread of the bacteria.
