LEPTOSPIROSIS: WHY RODENT CONTROL IS A PUBLIC DUTY

Considering the risk rodents pose to human health, including Leptospirosis, professional rodent control can be viewed as a public duty.

It is well documented that rodents spread disease. One of the most renowned is Leptospirosis, often called ‘the rat disease’, caused by spirochete bacteria of the Leptospira genus, which are principally carried by rodents. Leptospira can survive for months in wet soil and water and can infect animals and humans through direct ingestion of contaminated food and water or by contact with urine, contaminated material, food or water.

More common in tropical to subtropical regions, Leptospirosis is responsible for around 60,000 deaths per year globally.1 In recent years, we have seen an increase in the number of cases in Australia. In 2018, 84 cases were identified among workers of a berry farm in NSW and clusters of infected dogs dying from the disease were recorded in Sydney and Melbourne in 2019. In 2020, a total of 81 cases were recorded, and an outbreak of Leptospirosis occurred in the Northern Territory during the wet season in early 2021 with 14 cases. So far in 2022, Leptospirosis has been detected in dogs across NSW with cases on the Central Coast, Central and Northern Beaches areas of Sydney and more recently on the South Coast.

Leptospirosis is recognised as an occupational hazard for many people who work outdoors or with animals and is a recreational hazard to bathers and campers in infected areas. While often asymptomatic or leading to mild symptoms such as fever, muscle aches and headaches, around 10% of the infected population will progress to severe symptoms including organ failure, meningitis, respiratory distress and worst-case scenario, death. In non-lethal cases, full recovery often takes several months.2

Therefore, controlling rodent populations is a public duty. Today, the most effective means of controlling harmful rodents is the use of anti-vitamin K anticoagulant-based rodenticides, which represent more than 90% of products on the rodent control market.

“As opposed to common belief, today’s products are not the same as those of yesteryear,” said Romain Broch, operations manager at De Sangosse/Liphatech. “The term ‘rat poison’ is now out of date! Liphatech baits are formulated for and adapted to different species of rodents and their different living environments.

“For example, the Generation range of products have a very low concentration of active substance. Liphatech First Strike and Generation Block contain difethialone at 25 ppm (equal to 25 mg) of active substance per kg of finished product. The products are ready to use in the form of both soft bait or block bait and contain a bittering agent which reduces the risk of accidental ingestion by children, without affecting palatability of the product for rodents.

“To ensure efficacy, the product must be consumed in sufficient quantity. It must therefore be palatable enough to be preferred by rodents over food sources available on site. That is why bait quality is so important in determining treatment efficacy. Following the label instructions and best practice advice will ensure the success of a treatment and that the public health risk is managed.”

 

1 Costa F, Hagan JE, Calcagno J, et al. Global Morbidity and Mortality of Leptospirosis: A Systematic Review. PLoS Negl Trop Dis. 2015;9(9):e0003898. Published 2015 Sep 17. doi:10.1371/journal.pntd.0003898

2 Victoria Government Department of Health