What Diseases Do Cockroaches Carry?
Cockroaches are arthropods which are capable of transmitting diseases. Unlike ticks and mosquitoes, which transmit pathogens directly through their bites, cockroaches spread diseases indirectly due to their unhygienic habits. They contaminate surfaces with bacteria, viruses, fungi and parasites which are capable of causing disease in humans and animals. Cockroaches also play a role in the appearance of allergies in people sensitive to certain allergens. This makes it essential to take action against, especially in places where they are a danger to public health.
In this AnimalWised article, we will talk about the diseases transmitted by cockroaches to people, cats and dogs, as well as the measures to be taken to avoid them.
Why do cockroaches transmit diseases?
There are almost 5,000 species of cockroaches in the world. However, only 30 of these have a tendency to be pests and transmit diseases. Most cockroaches play a large ecological role because they feed on decaying organic matter, making nutrients available to other organisms. Wild cockroaches are active during daylight hours and mainly live in tropical rainforests.
Cockroaches that are pests are nocturnal and feed omnivorously, eating whatever they can find. They hide during the day in damp dark places, such as drains, septic tanks or sewers. At night they go to bars and restaurants, sanitary places such as hospitals, our homes or any warehouses with food products. They contaminate utensils and food, subsequently transmitting diseases.
The problem with cockroaches being pests is very clear: they can transmit diseases due to their eating habits and the areas they frequent.
What diseases can cockroaches transmit to people?
We are often told not to step on these insects, but why shouldn't we step on cockroaches? In addition to the fact that it is a cruel and unnecessary act, the cockroach acts as a transport vehicle for numerous microorganisms which are harmful to humans. These microorganisms can stay alive on their body, in their digestive system and excrement for days or weeks. So, for this reason, we should not step on cockroaches.
Germs on cockroaches come from the places where they circulate, such as sewers or the garbage, as well as the excrement of infected animals. Germ transmission can occur by regurgitation of food, by contact with their extremities or through contamination with their droppings. These germs can then be ingested by people eating cockroach-contaminated products.
Cockroaches can transmit diseases caused by bacteria, parasites, viruses, fungi and can also be responsible for allergic reactions in people.
Bacteria are the main group of pathogenic microorganisms transmitted by cockroaches. Indeed, they can harbor and transmit up to 40 types of bacteria. Some of them can infect people with the following diseases:
- Gastroenteritis, dysentery and cholera: it has been demonstrated that at least 25 types of bacteria transmitted by cockroaches belong to the group of enterobacteria, which cause gastroenteritis in humans. They are also capable of transmitting Shigella, a bacteria which causes infantile diarrhea and dysentery. Cholera is an acute diarrheal infection caused by the bacterium Vibrio cholerae. It is a disease most commonly transmitted in developing countries and places with inadequate environmental management.
- Leprosy: this disease is still present in places such as Brazil, Africa and Southeast Asia; it can be transmitted by cockroaches that carry the Mycobacterium leprae bacteria. Cockroaches spread it by coming into contact with the saliva of infected people, e.g. droplets from sneezing or coughing.
- Typhoid fever: another bacteria transmitted by cockroaches due to their feeding habits is Salmonella typhi, which causes typhoid fever.
- Salmonella: cockroaches, along with rodents, can transmit salmonella to humans. This is a disease that produces symptoms of food poisoning. The most common bacteria that transmit salmonella are Salmonella anatum and Salmonella oranienburg.
- Urinary tract infection: occurs in greater numbers in women and is caused by the consumption of food contaminated by cockroaches with Pseudomonas aeruginosa.
Cockroaches can also transmit certain parasitic diseases to humans, due to parasites such as:
- Helminths: after bacteria, helminths (roundworms) are the most common group of pathogenic organisms transmitted by cockroaches. They can transmit seven different species of helminth to humans. They can also transmit flatworm eggs through contact with the feces of a dog or cat who has Echinococcus granulosus. This is responsible for hydatidosis in humans (the formation of a hydatid cyst mainly in the liver [70% of cases]). In the liver it can produce pain, jaundice, palpable masses and fever. It can also occur in the lung, where it may cause coughing, hemoptysis, expulsion of blood or pus when coughing, and complications due to the rupture of the cysts.
- Protozoa: cockroaches can also transmit diseases caused by the protozoa Balantidium coli, Entamoeba histolytica, Giardia intestinalis, Toxoplasma gondii and Trypanosoma cruzi (which causes Chagas disease).
Several studies show that cockroaches can acquire, maintain and transmit certain viruses, such as the poliovirus that causes poliomyelitis and Coxsackie (which produces the disease commonly called Hand Foot and Mouth Disease). This disease mainly affects infants and children. It is characterized by the formation of a rash on the hands and feet and painful sores in the mouth. Cockroaches are also suspected to be carriers of hepatitis due to contact with the feces of sick people or food contaminated with the virus.
Cockroaches are also hosts of some fungi responsible for lung diseases, such as Aspergillus fumigatus and Aspergillus niger. There are also other associated with pathological conditions.
Apart from these diseases, cockroaches can produce an asthma attack in sensitive people when they inhale the proteins that cockroaches have on their body and skin. There are also people who are allergic to the feces and saliva of these arthropods. These allergies appear when people breathe in air from a place where the cockroaches have been present.
In addition to cockroaches, the rat is another animal that often transmits diseases to humans. Here is a list of the 10 diseases rats can transmit to humans.
What diseases can cockroaches transmit to dogs and cats?
Cats and dogs can become infected with protozoa (cyst-forming parasites), as well as bacteria and other microorganisms. Diseases and health problems which cockroaches can transmit to our pets include:
- Organ disease: toxoplasma gondii can kill off cells in cats, causing diseases of the stomach, liver, intestine, pancreas, lung, musculature, nervous system and eyes.
- Muscle cysts: the protozoan Sarcocystis species can cause muscle cysts in dogs and cats. They also cause anemia, fever, alopecia or increased levels of plasma enzymes (GOT, CPK and LDH).
- Neuromuscular problems: neospora caninum affects dogs, with puppies and older dogs being more susceptible. It mainly produces neuromuscular symptoms, such as paralysis of limbs, muscle pain together with atrophy and flaccidity, difficulty in swallowing, jaw paralysis and cervical weakness. In severe cases it may cause myocarditis and sudden death.
- Intestinal problems: just like with humans, cockroaches can also transmit the eggs of the flatworm Echinococcus granulosus. However, in dogs and cats this does not produce hydatid cysts. Instead, it lodges in the intestine of these animals and is mostly asymptomatic. It will cause signs of enteritis or mild and transient intestinal inflammation only when the parasite load is high. This is due to the fact that dogs and cats are definitive hosts of the parasite and not intermediary hosts like ruminants or pigs, or accidental hosts like people. It is important to deworm our dogs and cats to avoid this zoonosis.
- Digestive problems: other parasites that can be transmitted by cockroaches are ascarids, which belong to the group of nematodes. Toxacara canis is the parasite specific to dogs, Toxacara cati is specific to cats, and Toxascaris leonina affects both. These parasites pass into the lungs and liver after ingestion (by hunting or swallowing a cockroach) and then travel to their final location, the intestine, where they produce digestive symptoms. This is a zoonosis, and is mainly transmitted to children through unhygienic habits. Ancylostoma nematodes can also be transmitted by the same route, but they are more serious in young dogs and cats. These parasites feed on blood, and can also cause pale gums due to anemia, dark diarrhea, a dull coat, coughing, lung damage, lethargy and the inability to gain weight. These parasites can also be transmitted to people cutaneously when the larvae of these parasites penetrate the skin. producing the condition called ‘cutaneous larva migrans’. Alternatively, they are transmitted orally by poor hygiene. Such cases are usually mild since people are not the definitive hosts of these parasites, and the bacteria do not reach the adult stage until they arrive at the intestine.
As in people, cockroaches also seem to be able to spread enterobacteriaceae and salmonella to dogs and cats, and cause possible gastroenteric issues in our animals. Not only can cockroaches transmit disease to our pets, but some of them can be transmitted to humans via the dog or cat.
How to avoid diseases transmitted by cockroaches
The best way to avoid the diseases roaches spread is to stop them entering the home and thus prevent them from contaminating food or places we frequent. To help prevent this we can use the following tips:
- Good hygiene: perform proper hygiene for kitchen utensils and food products, especially those that will not be sterilized at high temperatures.
- Seal any holes in the house: check the pipes and possible places where these insects can reside, as well as reducing the damp conditions that they like so much. In health centers, the entry of goods that may carry cockroach eggs or nymphs should be controlled.
- Laurel: another option is to use home remedies to repel cockroaches. Laurel can be used as its smell repels them.
- Keep an eye on our pets: if our dog or cat is near a cockroach, we should stop them swallowing it. Also, we should check that their food and water dishes are clean and kept away from these insects.
In cases where there is already an infestation, these measures will not be sufficient and professionals should be contacted. Now we know the different diseases cockroaches can transmit to humans, we can take a look at some zoonotic diseases of birds.
This article is purely informative. AnimalWised does not have the authority to prescribe any veterinary treatment or create a diagnosis. We invite you to take your pet to the veterinarian if they are suffering from any condition or pain.
If you want to read similar articles to What Diseases Do Cockroaches Carry?, we recommend you visit our Infectious diseases category.
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