Myiasis, also known as bichera or worm, is a form of parasitism carried out by the larvae of dipterans (insects neoptera), such as flies, mosquitoes and even horseflies. They settle in living or dead tissues of vertebrate animals, on which they feed. All this ensures its survival, growth and even molting.
Have you observed wounds with worms in any part of your dog's body? Next, on our site, we will show you everything you need to know about myiasis in dogs, the symptomspresented, the treatment and the worm extraction procedure. We will also mention the contagion to humans and some home remedies to prevent it.
What is myiasis in dogs?
Hope (1840) was the first to use the word "myiasis" to define a diptera infestation, at that time in human beings humans. Later, Zumpt (1964) detailed the description of myiasis by suggesting that the insects spent some time in the host while feeding on body fluids or food ingested by the host.
These insects, in their adult stage, take advantage of holes or wounds of a host to lay their eggs, which will follow its biological cycle thanks to the parasitized animal. However, it may be that certain species are able to penetrate through the intact dermis. This pathology can affect all kinds of vertebrate animals, in any region, especially during the wettest months of the year.
Types of myiasis in dogs
There are three different criteria for classifying myiasis in dogs and we will mention them below. Likewise, in the first of them we will name the Diptera that cause canine myiasis.
Types of myiasis in dogs according to the clinical point of view
Depending on the clinical point of view and the causative agents, we distinguish the following types:
- Traumatic myiasis: Megaselia rufipes, Chrysomyia albicans, Phormia regina, Calliphora spp, Lucilia spp, Sarcophaga spp and Wohlfahrtia magnifica.
- Ocular myiasis: O. ovis, R. purpureus, M. scalaris, W. magnificent and S. carnaria.
- Auricular myiasis: O. ovis, and W. magnificent.
- Nasal, oral and sinus myiasis: W. magnifica, Sarcophaga carnaria, Calliphora vomitoria, Oestrus ovis, and Rhinoestrus purpureus.
- Anal and vaginal myiasis: W. magnificent, S. carnaria and Sarcophaga hemoroidalis.
Types of myiasis in dogs according to reproductive behavior
Canine myiasis can also be classified according to the way dipterans reproduce:
- Obligatory or specific myiasis: Diptera parasites that necessarily need a host for development in their larval stage.
- Semi-specific myiasis and accidental myiasis: in this case we are talking about Diptera that parasitize corpses or decomposing organic matter. They may opportunistically invade living tissue.
Types of myiasis in dogs according to invasion processes
Finally, we find the criterion that classifies myiasis according to the way in which the larvae parasitize the dog:
- Primary invader: penetrate the skin or take advantage of body openings.
- Secondary or tertiary invader: take advantage of wounds and traumas.
How does myiasis develop in dogs?
Diptera that are susceptible to myiasis usually have different forms in their biological cycle, going through a complete metamorphosis of four stages: egg, larva, pupa and adult. The last two phases do not live in the host. In this way, the adult Diptera introduce their eggs into the wounds of their hosts, in this case dogs, so that they hatch and larvae feed on their dead tissue. Once this stage is over, it leaves the host's body to continue its biological cycle.
The larvae secrete an enzyme that can damage the dermis and cause various he alth problems. If left untreated, the wound increases in size and a dark discharge appears, which causes many other dipterans to be attracted and begin to lay their eggs as well, causing what is known as "gusanera" or "bichera", worms in the dog.
Is there any type of predisposition?
Any animal that does not have an adequate sanitary control is susceptible to myiasis, therefore, abandoned, sick, convalescent animals or that have constantly moistened skin will be more predisposed. Acral lick dermatitis could be an example of the latter case.
Symptoms of myiasis in dogs
There are different types of myiasis: cutaneous, cavitary, systemic and wound Therefore, in some cases it can be more difficult to detect than in others. In addition, in the case of cutaneous myiasis we can observe several classes: furunculoid, rampant, traumatic and serpingous. It is also important to note that although we can initially detect a cutaneous myiasis, it can progress to become systemic, affecting different organs.
In the first phases of myiasis we can observe a small bite, lesion or abscesson the skin, usually in a hairless area. Later we will observe how the wound grows, a pustule begins to form and releases a serous or bloody fluid. Likewise, it is common to see directly the white larvae in the wound of the dog. Pay attention to all these symptoms:
- Ulcers
- Boils
- Skin irritation
- Skin lesions
- WormMove
- Edemas
- Fever
- Intense itching
- Ear flicks
- Pain
- Discomfort
- Scratch
- Excessive licking
- Diarrhea
- Anorexy
At this point (and if left untreated) the larvae can penetrate deeper layers of the skin, forming nodules, or simply create a much larger abscess. This whole process leads to the appearance of a serious infectious process and even a shock
As you can see, in cases of myiasis you can not only notice that your dog has worms in a wound, there are many more clinical signs that it can show, many of them serious if the problem is not treated.
Diagnosis of myiasis in dogs
By means of a simple physical examination the professional will be able to diagnose myiasis in dogs because, due to the rapid development of the larvae, the use of the microscope is not necessary. It will also be important that the veterinarian make a request for analysis in the laboratory.
How to cure myiasis in dogs? - Treatment
The treatment of myiasis in dogs must always be carried out under the supervision of a veterinarian These small worms in dogs can cause pathologies secondary, so you should never try to cure myiasis without visiting a specialist.
The first step to treat myiasis in dogs will consist of general hygiene of the area, for example with the use of physiological serum, although some specialists can proceed directly to the extraction of the larvae and wash the wound afterwards.
Wounds with worms in dogs, how to get them out?
Wound removal of maggots should always be done with use of tweezersIt is a laborious and slow process, since the larvae should never be broken when trying to remove them from the parasitized area. This process can be repeated several times.
Use of antiparasitics, drugs and hygiene
After removing the fly larvae, the vet will shave the affected area to prevent bacteria or eggs from remaining on the fur and the skin. After applying a antiseptic solution, the veterinarian will remove dead tissue to promote healing of the skin.
Antibiotics for myiasis in dogs
A local antibiotic will be applied and curabichera (a product which is also known as "matabichera" or "antigusanera") in spray or paste, applied directly to the wound until it is completely covered. Of course, the medicine for myiasis in dogs must be prescribed by the veterinarian. Finally, the affected area will be covered with a bandage to keep it clean and avoid possible environmental contamination, which will help it heal faster.
Finally, it is important to highlight that it may be necessary to use antibiotics, fluid therapy and other measures that the veterinarian considers appropriate depending on the evaluation of the case. Likewise, different visits to the specialist may be required to carry out a second extraction of worms, sanitization of the area or topical application.
Is myiasis in dogs contagious?
As we have explained previously, myiasis can affect any vertebrate animal, therefore, myiasis can be transmitted to humans and other animals.
People who live in a home with a dog suffering from myiasis should take certain precautions in order to avoid possible parasitism. It will be essential to monitor any wound and cover it, carry out daily hygiene baths, apply products or creams that avoid humidity or use insect repellents. We will pay special attention in the case of having babies, sick or elderly people in the home.
Prevention of myiasis in dogs
Although myiasis is not a common problem in large cities, it can be more common in rural areas or affect dogs that regularly go to rivers and forests. Just check the dog's skin regularly, paying special attention to areas without hair.
By maintaining a good level of hygiene, including brushing and bathing the dog, we can quickly identify this problem, which It will prevent more serious complications. Likewise, we will strictly follow the deworming in dogs, both internal and external.
It is also very important to go to the vet if you observe any of the symptoms of myiasis in dogs mentioned above, such as excessive scratching, compulsive skin licking or any abnormality.
Are there home remedies for myiasis in dogs?
Due to the complications that myiasis can cause, it is not recommended to use any type of home remedy to treat this pathology, beyond the use of tweezers to extract the worms from the dog's wound, and even then this process must be carried out by a specialist. Likewise, the use of any remedy is not necessary if the prevention advice mentioned in the previous section is followed.
Many people wonder if vinegar kills worms in dogs, but the truth is that, we repeat, this is not a remedy that you should apply because it is not effective and could even be harmful. Once the worms have been removed from the dog's wound and disinfected, you can complement the treatment with some remedies to help it heal faster. We talk about them in this other article: "Home remedies to heal wounds in dogs".
