A flea infestation may be annoying and the bites may be itchy, but in Australia we don’t really associate fleas with disease. However, it is easy to forget that the bubonic plague or ‘black death’ is spread by fleas, in particular the oriental rat flea (Xenopsylla cheopis).
A flea infestation may be annoying and the bites may be itchy, but in Australia we don’t really associate fleas with disease. However, it is easy to forget that the bubonic plague or ‘black death’ is spread by fleas, in particular the oriental rat flea (Xenopsylla cheopis).
Many may think of the bubonic plague as a disease of a time long past, indeed during the 14th century it killed an estimated 50 million people globally. However, even today there are around 650 documented cases a year, which result in around 120 deaths. Last year, Madagascar experienced a four-month epidemic, with around 2267 confirmed infections resulting in 195 deaths. Although it was hoped it was under control, new cases have appeared in 2018 and there is concern it could spread to other countries.
The disease is caused by the bacterium Yersina pestis, which firstly infects the oriental rat flea, which then infects its host, usually the black rat (Rattus rattus), through biting. Infected fleas can then also bite people living in close proximity to infected rodents. The bacterium moves into the lymphatic system causing inflammation of the lymph nodes – the resulting lumps or buboes that appear in the groin and armpits give rise to the name ‘bubonic plague’. The other symptoms of the disease are flu-like symptoms – chills, sneezing, feeling ill and muscle cramps. As the disease progresses, infection becomes severe and often the skin will start to decompose before the patient dies! The death rate is high – even with antibiotics, the death rate is around 10%.
Remember the nursery rhyme:
Ring-a-ring o’ roses (describes the swelling / buboes)
A pocket full of posies (dried flowers to cover the smell of decay)
A-tishoo! A-tishoo! (the flu like symptoms)
We all fall down (death is inevitable)
The potential for the disease to spread is based on the fact that although the disease is generally passed from fleas to humans (bubonic plague), some patients with the disease can develop pneumonic plague. This lung-based infection allows the disease to be passed from human to human through airborne particles. This latest outbreak in Madagascar consists of 70% pneumonic plague, which is very unusual. Neighbouring countries have been warned and indeed the UK Government has advised UK citizens to avoid travelling to Madagascar.
Could the plague come to Australia? Well, there have been no recorded cases since the last pandemic (between 1890 and 1926), which resulted in almost 1400 cases and 535 deaths in Australia. It is possible that the Yersina pestis bacterium still exists in some rodent populations, albeit at a low level. Indeed, health officials in Arizona, USA issued a health warning in August 2017 after fleas in the state were tested positive for the bacterium; there are several fatal plague cases in the US each year.
Whilst there is no need to scare customers, it does pay to be cautious when carrying out flea and rodent treatments – wear suitable protection to avoid getting bitten by fleas and wear gloves when handling dead rodents.
Although the plague may not be of immediate concern in Australia, typhus (both the rare cat-flea typhus and more common murine typhus) is a real possibility with flea and rodent infestations. Murine typhus (Rickettsia typhi) is found throughout Australia, but is more prevalent in the warmer areas. Transmission can be through a flea bite or through contact with contaminated flea or rodent faeces (that may become airborne when cleaning). The initial symptoms include flu-like symptoms and a rash one to two weeks after exposure, followed by vomiting and neurological symptoms (balance issues, confusion, seizures) as the disease progresses.
Such potential disease risks only emphasise the need for a comprehensive flea treatment when dealing with an infestation. Treating the pet with a suitable veterinary product and thorough vacuuming (consider wearing a mask) should be part of the initial treatment, before treating all infested areas (inside and out).
Sumilarv is recommended for all internal flea treatments, because it works on every stage of the flea life cycle and provides residual control for up to ten months. Sumiguard is the tried and tested adulticide to partner the IGR action of Sumilarv, providing the superior results that customers expect from their professional pest manager: – long-lasting control and protection from potential diseases.
Back to the articles on pest control fleas or more information on rats and fleas.
Charles McClintock, Professional Products Business Manager, Sumitomo Chemical Australia