Even at the best of times rats are one of the most problematic pests for businesses handling food, and for homes in urban areas with any source of food nearby. Now, during the COVID-19 global pandemic, even rats are under pressure. Data collected by our Rentokil Initial technicians shows a definite increase in rat infestations in January – May 2020 when compared directly with January – May 2019.
And this is because throughout urban areas, there are populations of rats that previously relied on a ready supply of food from businesses making or selling food. Food waste is generated not just in restaurants, cafés and fast-food outlets, but also in offices and other businesses where employees take their own food into the buildings. Normally, rats live close to their food sources. Now, however, the widespread closure of businesses of all types during lockdown has meant that these regular sources of food have disappeared. Urban rats are now facing hunger in their own territories, which is driving them to change their normal behaviour. They are no longer nocturnal and wary of people or new surroundings, but are becoming increasingly more bold, and are venturing into new locations.
Risks posed by rat infestations:
This change in rodent behaviour – as large numbers of rats try to access new areas for shelter and food -presents some risks to humans. These are:
Rapid population growth:
Rats are fast breeders when food is plentiful and there is little predation. In urban areas, even the presence of cats and dogs has little effect on rodent numbers and, in some cases, may even result in more food being available (rodents love pet food!). Brown rats have litters of 7-8 pups and can have from 3-6 litters per year. The pups take 2–3 months to reach sexual maturity, at which point, the females from this first litter can mate and, within 21 days, produce 7–8 pups each. These pups go on to have 3–6 litters per year. With a ready supply of food and lack of pest control, a rat population can increase exponentially in a new area.
Rats are also highly adaptable to their surroundings and the availability of food, water and shelter. An urban environment generally offers an abundance of these both indoors and outdoors. Their agility, curiosity and intelligence means they’re very adept at finding new places suitable for their survival.
Finding a new area triggers a rapid growth in population until factors become limiting. The same effect occurs when pest control strategies are not sufficient to wipe out a population. Rats can quickly restore their numbers with successful breeding until competition for resources limits breeding and survival.
Rats spread disease and parasites:
As we’ve discussed in some of our other blog posts, rats can spread a wide range of diseases and parasites to the urban areas they infest. A single rat can also carry multiple types of pathogens and parasite, including bacteria, viruses protozoans, and parasitic worms. Rats also carry ectoparasites that include fleas, ticks, lice and mites, which are all vectors of other diseases. They contaminate their runs and the places they visit with urine, faeces and saliva, which can also transmit diseases. These include:
• Leptospirosis and Weil’s disease: Leptosopira bacteria
• Rat-bite fever: Streptobacillus moniliformis and Spirillum minus bacteria
• Cryptosporidiosis: Cryptosporidium species of protozoa
• Rat tapeworm: Hymenolepis nana and H. diminuta (a beetle such as a flour beetle can be a secondary host)
• Toxoplasmosis: Toxoplasma gondii protozoan
• Salmonellosis: Salmonella bacteria
Means of infection:
There are many ways that we can catch a disease from rodents: either indirectly from the places they have infested, or directly by coming into close contact with them:
• Drinking contaminated water or eating contaminated food.
• Inhalation or direct contact with rodent excreta (urine, faeces, saliva) on contaminated surfaces.
• Handling or inhaling microorganism-containing particles aerosolised from hay, woodpiles or other materials contaminated with infectious rodent urine.
• Particles in dust made airborne by sweeping places where rats are present.
• Handling of infected rodents.
• Bites and scratches — microorganisms carried in saliva can infect both humans and other rodents.
• Dogs and cats eating rodents and then catching parasites such as tapeworms that can be passed on to humans by them.
• Rodents can also act as reservoirs for various flying-insect-borne diseases.
With our health services under immense pressure to make resources available for COVID-19 patients, they have reduced capacity to deal with other diseases. Rat infestations create multiple threats to health, and it is therefore vital to maintain pest control measures to both protect food supplies and prevent overloading of health services.
Damage to products and property:
Rats cause significant damage to property from their tendency to burrow and their ability to gnaw through just about anything. They do this to either gain access to a location (for food or shelter) or simply to wear down their teeth, which grow continuously. Rat’s teeth are hard enough to gnaw wood, aluminium, plastic, lead and even some types of steel — which is why gnaw marks are often the first sign of an infestation.
A survey by the Centre for Economics and Business Research (Cebr), commissioned by Rentokil found that rats were the most destructive pest for businesses. They cause gnawing damage to buildings and fixtures, making holes to gain access around doors, windows, pipework, drains – they can even swim round toilet U-bends!
The most common problem reported by businesses was damage to electrical equipment, with 49% reporting machinery or wiring as most affected. This can result in production downtime or fires when rats gnaw through the plastic insulation and short the wires. Can you imagine the havoc they could cause in a server room?
Consume and contaminate food supplies:
Rats need to eat about a tenth of their body weight each day and have daily access to water. They nest near their food supplies and make multiple visits to their food sources. They contaminate the food and surrounding surfaces with urine, droppings, and filth picked up from the environment. Whatever they gnaw will also be contaminated with their saliva. Rats are capable of gnawing through many types of food packaging, including cardboard, paper, plastic, and multilayer packaging materials. This causes loss of stock to businesses both from the food rats eat and contaminate or leave in damaged packaging.
The economic cost of rats:
Rats are both a financial and business risk, and pose a risk to public health and food security. Infestations can result is multiple costs, including:
• cost of the treatment to eradicate rats
• repairs to property
• replacement of contaminated stock or defaced items
• loss of reputation for towns, cities and businesses
• loss of business
• potential litigation
Professional pest control services perform a vital function to prevent the populations of rats in urban areas growing out of control during lockdowns. With health services already overloaded from dealing with Coronavirus patients, it’s essential to take measures to prevent other sources of illness.
Rentokil has been in business for more than 50 years in South Africa and uses industry-leading solutions to tackle infestations across the country. Contact a local expert today to control rodents in your area and minimise the risks to your business or home.