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Cockroaches are synonymous with filth and poor hygiene. Their feeding and nesting habits mean they can accumulate a range of pathogenic organisms which they transmit to food and surfaces where they feed and crawl.
For businesses, this can impact customer and staff health. In addition, for businesses handling and processing food, it could result in a breach of food safety laws.
Transmission occurs indirectly, from consumption or contact with items that have been contaminated by cockroaches. Cockroaches are reservoirs of disease-causing organisms, not vectors themselves. They can spread diseases through:
Similar to rodents, cockroaches are known to transmit the Salmonella sp. bacteria which can cause salmonellosis, a disease in humans with symptoms similar to food poisoning.
Cockroaches accumulate the bacteria by crawling in filth and feeding on contaminated food materials. The Salmonella remains in their digestive system for a month or more and is deposited through their vomit and feces.
Human symptoms, which typically show 12 to 72 hours after infection, include diarrhea, fever, and vomiting (to name a few). Recovery usually occurs after four to seven days, with little to no medical treatment need, besides replenishing fluids.
Typhoid fever is a bacterial infection caused by the Salmonella typhi bacterium and is a highly infectious disease. It is believed that cockroaches accumulate this disease by consuming feces contaminated with the bacterium.
Typhoid fever is most common in developing countries where there is poor sanitation and limited access to clean water. Americans are primarily diagnosed with Typhoid after traveling internationally.
The symptoms of typhoid fever include, but are not limited to:
Dysentery is a type of gastroenteritis that results in bloody diarrhea. Generally, most people suffer from mild symptoms and recover within a week or so without medical attention
Dysentery is usually spread through poor hand hygiene and consuming contaminated food and drink. Symptoms are diarrhea containing blood and mucus, painful stomach cramps, nausea and vomiting, and a high temperature.
Cockroaches, along with other insects, are suspected of being carriers of the bacillus Mycobacterium leprae which causes leprosy.
Cockroaches are believed to spread the disease through their feces. While the bacteria are not highly infectious, if left untreated, it can cause permanent damage to the skin, nerves, eyes and skin which can lead to disfigurement and deformities.
Leprosy has an incubation period of around five years but symptoms may take as long as 20 years to appear. Treatment is possible using multidrug therapy (MDT).
Although it’s regarded as a rodent-borne disease, cockroaches are also suspected of spreading the Yersinia pestis bacterium which causes plague.
Common symptoms of plague include, but are not limited to:
People infected by the plague need to receive urgent treatment and should be given antibiotics 24 hours after infection to avoid severe consequences.
Campylobacteriosis is an infection caused by the Campylobacter bacterium. It is one the most common bacterial infections in humans, and is a common foodborne illness. Researchers have isolated a Campylobacter jejuni subspecies in the gut contents and on the external surface of both American cockroaches and Oriental cockroaches.
Transmission occurs through ingesting contaminated food and drink such as unpasteurized milk and undercooked or poorly-handled poultry. It can also be transmitted through sexual contact, although this is very rare.
Symptoms of campylobacteriosis include bloody diarrhea as well as cramps, abdominal pain and fever. The disease usually lasts for 2-10 days and requires little to no medical treatment.
Listeriosis is a serious infection caused by the bacterium Listeria monocytogenes. It is usually contracted by consuming contaminated food and drink. According to the Centers for Disease Control (CDC) it is an important public health problem in the United States.
Listeriosis primarily affects people with weakened immune systems such as pregnant women, newborns and the elderly. Although rare, people with strong immune systems can also be affected.
Symptoms of listeriosis are usually a fever, muscle aches and diarrhea. However, if the diseases spreads beyond the gastrointestinal tract, symptoms can also include headaches, a stiff neck, confusion, loss of balance and convulsions. For pregnant women, contracting listeriosis can sometimes lead to miscarriage, stillbirth or premature delivery.
Escherichia coli (E. coli) is a bacterium commonly found in the gut of humans. Although most strains of the bacteria are harmless, some can cause serious food poisoning.
The common symptoms of an E. coli infection are diarrhea and abdominal cramping. Less common symptoms are:
Symptoms usually last three weeks and require little to no medical support.
Although they are not necessarily referred to as diseases, there are a handful of bacteria that cockroaches spread which could develop into serious infections.
Staphylococcus aureus
This organism is generally harmless, but can cause serious infections. Infection can occur in many forms ranging from minor skin infections, such as boils, to infections of the blood, lungs and heart. Cockroaches are known to carry the bacterium on their exoskeletons or in their digestive tracts.
Streptococcus
Like Staphylococcus aureus, Streptococcus infections come in many different forms, from mild throat infections to life-threatening infections of the blood or organs.
To add to the other bacterial diseases transmitted by cockroaches, there is also a link between these crawling insects and asthma.
The cockroach allergy was first reported in 1943. It was discovered when patients developed a rash after cockroaches crawled on their skin.
Cockroaches can trigger asthma because they have certain proteins in their bodies which can be an allergen for certain people. When tiny particles from cockroach bodies are spread through the air in buildings, these proteins are inhaled, triggering an asthma attack in sensitive people.
The American College of Allergy, Asthma & Immunology reports that the saliva, feces and shed skin of cockroaches can trigger both asthma and other allergic responses.
The World Health Organization estimates that 300 million people worldwide suffer from asthma. It has been discovered that frequent hospital visits of children living in cities suffering from asthma can often be due to contact with cockroaches. Around 23-60% of people with asthma are sensitive to cockroach allergens.
The most common form of transmission of a disease from a cockroach is from eating or drinking anything it has contaminated. This can either be through consuming food or drink contaminated by cockroaches, or by eating or drinking something that has been made using contaminated cooking utensils, cutlery or crockery, or touched contaminated surfaces.
If the air supply is contaminated with proteins from cockroach feces, vomit or shed skin and this is inhaled by people suffering from asthma, an attack can be triggered.
Touching items contaminated with an organism deposited by cockroaches is also a route through which transmission can occur. Touching an item which has been contaminated then touching your eyes, nose, mouth or an open wound can result in the pathogen entering the body and infection setting in.
Aside from spreading diseases and contaminating food in restaurants and grocery stores, cockroaches can cause a host of other issues for businesses. For hospitals, nursing homes, assisted living facilities, hotels, resorts, retail stores, and apartment complexes, a cockroach infestation will lead to a failed health inspection and potentially a temporary building closure.
Furthermore, your business’s positive reputation of cleanliness and safety is what keeps people returning to your establishment as patrons. Knowledge of cockroach sightings in your building from those that frequent your business can severely damage the years of good rapport you have built with your customers.
Don’t put the success of your business on the line by ignoring a cockroach infestation. If you have noticed any of these disease-spreading pests in your business, contact Rentokil for professional treatments to get rid of cockroaches quickly.
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