Analysis for dirofilariasis in dogs diagnostics. Adulticidal and auxiliary therapy. How the disease develops in dogs: symptoms of dirofilariasis

Dirofilariasis is a dangerous, almost tropical disease that last decades confidently moving towards the northern regions of the Eurasian continent. The disease, previously characteristic only of countries with a warm climate - Turkey, Sri Lanka, the USA, Italy, Hungary, and the Balkan Peninsula, has gradually spread to areas with a temperate climate. It has been registered in the North Caucasus for quite some time, Black Sea coast, . However, in temperate climates dirofilariasis in dogs did not stop, but continued to spread northward. While undergoing acclimatization and evolving, the pathogen eventually adapts to more low temperatures. IN given time outbreaks of dirofilariasis are recorded on the territory of the Russian Federation north of Tyumen.

As a rule, three successive stages of molting and the formation of an infective larva in the intermediate host take from 14 to 20 days. When bitten again, the dangerous dirofilaria larva, together with the mosquito’s saliva, enters the subcutaneous tissue of the main host, where it receives further development. It can last from 3 to 5 months and only then the larva actively penetrates the dog’s circulatory system, entering the pulmonary arteries and right atrium. One bite from a mosquito carrying infectious larvae is enough to make an animal sick.

While in the pulmonary vessels of dogs, dirofilariae undergo further formation and after another 4 months (and about 7 months from the start of infection) they begin to actively secrete new microfilariae. A year after infection, the activity of nematodes and their release of microfilaria larvae becomes maximum. Such active release of larvae occurs throughout the life of an adult heartworm and usually lasts about 7 years.

Given the danger of this disease and the seriousness of its complications for the dog's body, a responsible owner should take an interest in the ways in which heartworm disease spreads and check with a local veterinarian to determine whether dogs with heartworm disease are identified in the area. Due to the fact that canine dirofilariasis is transmitted through mosquitoes, even those animals that never leave the house get sick.

That is why active preventive measures are so important, primarily to prevent bites from blood-sucking insects. The insectoacaricidal drug Advantix www.advantix-dog.ru copes best with this task. It must be used as a drip for cutaneous application once a month for at least five months a year.

Methods and rules for preventing dirofilariasis in dogs

In fact, prevent dirofilariasis in dogs, and thus with a high degree of probability avoiding infection of your pet, is not so difficult. To do this, it is enough to regularly and constantly treat the dog. special drugs- macrolides in prophylactic dosages. At this time, 4 types of macrolides are widely used: Selamectin, Moxidectin, Ivermectin And Milbemycin. They correspond to the commercial names of the drugs, respectively: Stronghold, Advocate, Ivomak, Baymak and Milbemax. The dosage of drugs is individual and the veterinarian must select a prophylactic dose for the dog; or the owner should at least consult a specialist before using them. It is worth remembering that these drugs can be somewhat toxic and immunosuppressive. However, in preventive doses, their use is allowed even for puppies, pregnant and lactating animals.

Any of these drugs must be used according to a strict regimen and never be interrupted. Their administration is recommended once a month for 12 months throughout the dog’s life. It is necessary to start using the medicine from eight to nine weeks of age. In regions where dirofilariasis is recognized as an epidemic and the number of infected dogs is significant, the use of monthly constant prevention Necessarily. In such regions this is often regulated by veterinary legislation.

Macrolides are able to inhibit dirofilariasis infection and repel their intermediate hosts and carriers - mosquitoes. In case of infection, given the fact that the larval stage is in subcutaneous tissue and muscles of the main host for up to 3 months and does not penetrate the circulatory system, macrolides kill this larval stage as they are applied monthly. The most important thing in prevention is its regularity and consistency.

Methods for diagnosing dirofilariasis in dogs

When diagnosing dirofilariasis in dogs It should be remembered that in the vast majority of infected animals, characteristic symptoms may be missing a long period time. Most often, the disease occurs without symptoms for months or even several years. However, in regions unaffected by dirofilariasis, diagnostics in dogs is mandatory. It is worth remembering that when symptoms appear fatigue, cough, weight loss, shortness of breath, fainting, and especially when acute symptoms development of right ventricular heart failure, ascites and edema, treatment may no longer be effective. At significant volume helminths in circulatory system and their microfilariae larvae, and even more so if they die naturally, over time the dog may develop pulmonary embolism, respiratory failure, increased body temperature, and coughing up blood. But these are extreme manifestations of the symptoms of heartworm disease in dogs, which are quite easily confused with other diseases. As mentioned above, treatment of such patients is difficult. The task veterinarian and the animal owner to prevent infection, but if it does occur, diagnose it at the earliest stages.

Therefore, the earliest and most important diagnosis of dirofilariasis in dogs is laboratory diagnostics. The most informative are disposable test systems. They react to a protein that the female dirofilaria secretes with its cuticle. The more female heartworms there are in the circulatory system, the brighter the test results. IN in rare cases test system results may be false negative. As a rule, this occurs when there is a predominant infestation of heartworms, not females, but males, when treatment for heartworm infection is being carried out, or when the infestation is “young” (individuals have not reached a certain size). Often, false negative results are also obtained when the instructions of the test system are violated and are used incorrectly. In other words, testing must be done several times over a certain period of time, or better yet, regularly once every 2-3 months.

The second important component of diagnosing dirofilariasis in dogs is the detection of microfilariae in the blood. If they are detected, then adult nematodes secreting them are also present in the circulatory system. This technique is simple and inexpensive. If microfilariae are detected, it is necessary to carry out express diagnostics, determine the presence of antigen, and confirm helminth invasion. With this kind of disease, it is advisable to carry out a number of diagnostics that confirm one another.

In the next article we will talk in more detail about what it is, its main methods and schemes.

As well as the main methods of its diagnosis and prevention. In this article, we suggest that you familiarize yourself with the methods of treating it in dogs.

Adulticidal therapy

Auxiliary therapy for dirofilariasis in dogs should be carried out regardless of the degree and intensity of helminth damage to the animal. Use of combination therapy Ivermectin and Doxycycline immediately before starting adulticide therapy can significantly reduce the likelihood of injury lung tissue developing due to thromboembolism. Although comprehensive, documented studies of the effectiveness of combination therapy have been carried out only for one of the macrolides - Ivermectin, the remaining macrolides (Selamectin, Maxidectin, Milbemycin) are also suitable for complex therapy dirofilariasis in dogs. The dosage of drugs should be the same as that used to prevent the disease. Small doses are once every 30 days, but some deviation from the generally accepted scheme is possible - once every 14-15 days. The essence of the prescription of macrolides in complex therapy is to destroy microfilariae, young heartworm larvae (up to four months of age) and prevent re-infection.

The use of Doxycycline is necessary, first of all, to destroy Wolbachia and relieve glomerulonephritis and eosinophilic pneumonitis, as a consequence of the negative effect of Wolbachia on the dog’s body. Recommended dosages of Doxycycline are 10-12 mg/kg 2 times a day for 28 days. Doxycycline, in addition to actively damaging Wolbachia, can also to some extent reduce the activity of microfilariae and, thereby, enhance the effect of macrolides.

The use of corticosteroids in the complex treatment of dirofilariasis in dogs is also justified and indicated for any intensity of invasion. The most important effect of corticosteroids is their effect of immunosuppression and potent suppression inflammatory processes. It smoothes out the “sharp edges” of adulticidal therapy: it stops the negative effect of Melorsamine, reduces the severity of eosinophilia and microfilaricidal therapy. But its very long-term use is also not recommended due to excessive immunosuppression of the body and increased damage to the pulmonary arteries. Prednisolone is usually prescribed for 4-5 weeks at the initial diagnosis of heartworm disease and then again after the first injection of Melorsomine, and then again again for 4 weeks after the second injection of Melorsamine. This is the most justified scheme for its use.

Heparin is also sometimes prescribed for the complex treatment of dirofilariasis. It is applicable for 5-7 days after each injection of Melarsomin and effectively reduces the severity of thromboembolism.

The use of aspirin, on the contrary, is not justified, and latest research directly prove its low effectiveness in the complex treatment of dirofilariasis in dogs. Some complications of aspirin use, expressed in damage to the pulmonary arteries, can generally complicate the course of dirofilariasis.

Summarizing the above material on the treatment of dirofilariasis in dogs, we can confidently say that only complex treatment treatment of this dangerous disease can be truly effective. Any half-measures for the treatment of dirofilariasis are completely unjustified.

People do not get dirofilariasis very often, but infection with this dangerous helminthiasis quite possible. Despite the significant risk of infection in regions highly endemic for dirofilariasis specific prevention does not yet exist for people. In places with a large number infected dogs are recommended to active use repellents.

Dirofilariasis is an “evil thread,” as the name of the disease is translated from Latin. Dirofilaria - nematodes white, they primarily affect canines and cats, and in rare cases humans. They are localized, depending on the species, under the skin and in the ventricles of the animal’s heart. The disease occurs in many countries, more often in the south.

IN Lately cases of diagnosing the disease in temperate latitudes have also become more frequent. Heartworm disease in dogs is transmitted through mosquitoes. Due to its increased relevance, it is worth getting to know this disease better.

What is it and how can your four-legged friend get infected?

There are two types of heartworms.

• Heartworms D. immitis vary in length depending on gender. Females - 23-31 cm, males - 12-19 cm long.
• Another type is subcutaneous, D. Repens. Females - 10-17 cm, males - 5-7 cm long.

The mosquito bites the animal again, a different one, injects mature larvae, and the dog gets sick. Until microfilariae have entered the blood of a mosquito, they are not dangerous for the animal and can live in the blood for up to two years without manifesting themselves in any way. The parents of these microfilariae were most likely destroyed during.

Important! Treatment is mandatory; ignoring the problem can be fatal.

Larvae of one type reach the heart, others remain under the skin. It is heartworms that pose a threat to life.

How does it manifest in a dog?

There can be different amounts of helminths in the blood. When a critical amount is reached, symptoms of dirofilariasis appear, and it is clear that treatment is necessary.

The signs are:

• the animal is coughing;
• wheezes when breathing;
• suffocates;
• swelling;
• gets tired quickly;
• losing weight.

The symptoms of subcutaneous dermatitis are milder, it is not life-threatening, as with pulmonary dermatitis.

Dermatitis, itching, skin nodules, flaking hair, swelling of the mammary glands- the phenomena are unpleasant, but you can fight them.

Diagnostics

Dirofilariasis in dogs is detected the following analyzes and methods:

Treatment methods

Treating dirofilariasis in dogs is difficult, expensive, and problematic, since there is no 100% guarantee of cure. You cannot do without a veterinary clinic; there must be control over this process.

Treatment of dirofilariasis is carried out in the following main areas:

• Destruction of adult heartworms and all forms of their development.
• Preventing the formation of blood clots in blood vessels.
• Heart function support.
• Elimination of complications.

Dangers during treatment:

To prevent heartworm infection in a dog, the owner needs to seriously worry about prevention. In particular, protect your pet from mosquito bites. Some owners do a simple but effective thing: before a walk, they spray the dog’s fur with mosquito repellent spray, the same spray that people use when they go outdoors.

There are plenty of mosquito repellents in any pharmacy, and they are all effective. These simple and available means. It can protect you and your pet from many troubles and even save the life of your beloved creature.

A new remedy for heartworms has appeared on the market for dogs - IN-AP complex. It is applied to the dog’s skin once at the beginning of summer, and the treatment is repeated every 6-7 weeks. The drug is absorbed into the skin, enters the blood, where it destroys exactly what is needed - the larvae heartworm. Application doses are indicated in the instructions for use.

Every conscientious owner who has encountered lungworms in a dog is naturally tormented by the question - is it all in vain? Whether dirofilariasis can be cured or not, or maybe there is no point in suffering yourself, torturing your dog, wasting money and time. There is a problem. After all, a dog is often a member of the family, and not just a pet.

The prognosis is favorable if the diagnosis is made in a timely manner and there are no serious complications. Then it makes sense to spend money and waste time. The reward will be the gratitude and unconditional love of a devoted dog's heart. All you need to do is be attentive to your pet, and then no worms are scary for him.

Is it transmitted to humans from dogs?

Dirofilariasis is a disease of dogs and wild animals that can be transmitted to humans.

Important! Difilariasis is transmitted to humans not from dogs, but from mosquitoes.

Previously, people caught this disease in those regions of the Earth where it was hot and humid climate. Simply where there are clouds of mosquitoes. Now the situation has changed somewhat; infected mosquitoes have appeared in temperate climates. A person is more often infected with the subcutaneous form of these helminths.

Dirofilariasis is a dangerous disease. You need to remember this if you don’t want to lose your four-legged friend.

Dirofilariasis in dogs is a disease caused by nematodes of the genus dirofilaria. Mature individuals reach up to 40 cm in length and up to 1.3 mm in diameter.

Representatives of the canine family are their main hosts. Coyotes, wolves, ferrets, foxes, cats, sea lions, muskrats, roaches, and humans are all potential victims. The intermediate host is a mosquito. The approximate number of helminths that infect a dog is from 1 to 250.

How does a dog become infected?

Females are viviparous and produce larvae that accumulate. They can be detected in dirofilaria immitis - in the evening, and in dirofilaria repens– at night, when mosquito activity is highest.

The larvae, which enter the mosquito with blood, go into its Malpighian vessels, where they mature to become invasive. After this, they move to the head and gather around the mouthparts.

After a mosquito bite, heartworms end up in the blood, where they then find their localization.

Dirofilaria immitis penetrates pulmonary artery and heart, dirofilaria repens are localized in the subcutaneous tissue. Mature d. repens become infected up to 8 months, and individuals of d. immitis after 8–9 months.

The first - subclinical form is nonspecific symptoms. There is a fickle appetite. From the outside nervous system manifests itself as convulsions, collapses and cuts.

The animal gets tired quickly.

The second form is cutaneous. The skin of the extremities, back and head is affected. At the first stage - hair loss, the second stage - the skin turns red, pustules with pus appear, at the final stage - ulcerations.

A typical symptom is resistance to antibacterial and anti-inflammatory drugs. The third form of the disease is pseudotumor.

It is expressed by tumor-like growths on the skin surface of the thighs, back, metatarsals and mammary glands. Ulcers appear in which serous contents cover the surface of the skin.

The fourth is cardiopulmonary. Characterized by renal failure, anemia of the mucous membranes, prostate cyst, enlarged spleen, liver and ascites.

The dog becomes weak and short of breath. Electrocardiography shows hypertrophy of the ventricle and right atrium.

Diagnosis of dirofilariasis in dogs

Treatment of dogs infected with d.repens ends successfully almost every time. For the treatment of animals whose body has been attacked by d.immitis, with moderate severity– the prediction of a favorable outcome is low, and in severe cases it is doubtful.

Before starting treatment with macrofilaricidal therapy, it is necessary to make a prognosis for the animal’s life. It may happen that death occurs much sooner during treatment than without treatment.

Because individual drugs capable of provoking strong congestion microfilariae in vascular bed, and vascular embolism occurs (strokes, necrosis, paresis).

The most important thing in concluding an intravital diagnosis is the detection of microdirofilaria in the blood. Most of them are found in dogs affected by d. immitis, can be detected in the evening.

In case of defeat d. repens - at night. To diagnose an animal during life, scientists have proposed many methods. For example, the Knott method is often used in practice.

It lies in the fact that in order to find out whether a dog is sick, they take an analysis for dirofilariasis. venous blood and dilute it with formaldehyde and mix.

The remaining sediment is combined with methylene blue, and within 5 minutes the sediment should become colored, after which it can be examined for the presence of microfilariae.

Many countries around the world produce reagent kits for detecting heartworm antigens and serological diagnostics in an enzyme immunoassay test.

After the death of the animal, diagnosis is made through a pathological autopsy and identification of helminths and their localization.

Treatment of dirofilariasis

Often owners who have learned about the diagnosis ask to euthanize the dog, although in many cases this should not be done. Although the treatment is very expensive, it can be done.

To destroy mature heartworms, medications containing arsenic or ivomec are usually used.

Treatment of dirofilariasis mainly involves the use of the following deworming drugs: brovanol-plus, levamisole, macrolide drugs, thiacetarsamide. Now dirofilariasis in dogs can be treated effectively, but very expensive.

Sometimes for a reason individual characteristics Some dogs may experience toxicosis or other side effects.

For get well soon Prescribe drugs that activate the reticuloendothelial system and the functioning of the red bone marrow.

In order to avoid heartworm disease, you need to know some precautions. The first priority should be to prevent dogs from coming into contact with blood-sucking insects.

During the warm season, animals are most vulnerable, so you should definitely buy an insectoacaricidal collar for your dog; it repels up to 98% of mosquitoes and prevents infection for up to six months.

Periodically you need to do tests for the presence of helminths in the animal’s body and take prophylactic drugs.

Dirofilariasis in dogs is a rather dangerous ailment that affects mainly dogs and felines, and sometimes (albeit very rarely) humans. It is called roundworms(dirofilaria, from Latin - “scarlet threads”), affecting, depending on their type, the skin or heart, lungs of animals.

You need to know the “enemy” by sight

Heartworms use mosquitoes as an intermediate “station” for their temporary residence. These viviparous worms go through several stages during their development. The whole danger is that they strive to get into blood vessels, heart and muscle tissue dogs where they can successfully breed.

IMPORTANT! Dogs are generally susceptible to heartworm infection. This has been proven as a result experimental research. During the course of it, all the animals that were bitten by a mosquito infected with their larvae became ill with dirofilariasis. In the wild, these worms often infect wolves and jackals, which then become part of the reservoir hosts.

By the way, microfilariae without remaining in the blood of a mosquito do not pose any threat at all; in this form they can exist for 2 years without making themselves felt at all. The blood of an insect is the medium for their ripening, which differs in different periods.

How does a dog become infected?

The ripening cycle depends on the air temperature: the warmer it is, the faster it goes. It is interesting that when it gets colder, the larvae, without making themselves known, wait for warming. When they return to a comfortable temperature, the cycle continues again. All this usually lasts from 7 to 9 months. It is in the blood of their victim that dirofilariae complete the ripening period and begin reproduction, after which they move to the heart, where they settle.

Worms that live in the heart and causing disease, round shape and white. Their larvae are called microfilariae, and the adult worms are called heartworms. The larvae usually develop in the animal's blood and, along with it, spread throughout the body.

If you do not start treatment in a timely manner, such a nuisance may arise. Medications will destroy the worms, but what remains of them can contribute to the occurrence of thromboembolism. Worms in the heart of dogs always threaten their health. If the disease is neglected, it usually ends in their death.

The cutaneous form of dirofilariasis also creates certain problems for the animal. It usually suffers from dermatitis, itching, and rashes. But that doesn't affect me at all internal organs and does not pose any threat to the dog's life. The helminths in question in the form of larvae and true worms are located in this case in the subcutaneous fat. But they are successfully removed surgically, and after a therapeutic course, which for this ailment is indicated after surgical intervention, the disease goes away.

Symptoms of dirofilariasis in dogs

One of the first and most important symptoms of a dog affected by worms is the presence of protein exceeding the norm, so-called proteinuria. It develops because heartworm larvae affect the animal’s kidneys.

In the skin form of the lesion, the malaise is limited to intolerable itching, rashes, and inflammation in the place where the worms have found their refuge. The dog itches so much that tufts of hair fall out and swelling appears. The resulting infection can “hide” the place where the worms are located. The cardiopulmonary form can manifest itself with symptoms such as:

• Dyspnea;
• Coughing;
• Coughing up bloody sputum;
• Swelling of the paws;
• Lethargy;
• Reluctance to eat;
• Apathy;
• Fast fatiguability;
• Chills;
• Low-grade fever.

The most noticeable symptoms of this pathology make themselves felt on late stages diseases. It was then that the heartworm larvae, having reached adult stage, die. If there were a lot of helminths, then their decay products contribute to the development of intoxication in the dog’s body.

During this period, the animal may experience:

• weight loss;
• accumulation of fluid in the abdominal cavity;
• blue mucous membrane;
• weakness, even fainting;
• hoarseness, etc.

The treatment method depends on the symptoms. But this is still closely related to diagnosis. It's only right established diagnosis allows you to select those medications that will be effective for this particular case.

IMPORTANT! For more effective treatment It is very important to keep your pet in a specific small room or enclosure. It is also advisable to exclude physical exercise for the dog, because even running can affect the final result of the therapy. If your pet still needs Fresh air, then very short walks are recommended.

Diagnosis of the disease

Qualitative determination of dirofilariasis in dogs is not such a simple process. False results diagnostics are not that rare. This is explained by many factors, including:

• the infection occurred recently;
• in the blood of the larvae there are predominantly males;
• rules were violated when testing the animal.

The test will not give correct result, if the dog before him was given prophylactic drugs against dirofilariasis.

Treatment of dirofilariasis in dogs is difficult and expensive. But, most importantly, there is no complete guarantee of getting rid of this problem. Therefore, this process requires special control by specialists. Without veterinary clinic and her doctors are indispensable here.

Therapy for dirofilariasis involves the following areas:

• death of adult worms and all their larvae;
• prevention of thrombosis in blood vessels;
• maintaining cardiac function;
• preventing possible complications.

If dirofilariasis in dogs is of the cutaneous type, then surgical extraction is used adult dirofilaria. Damaged areas skin treated with a solution of Imidacloprid 10% and Moxidectin 2.5%. Usually the results of such actions are not bad. Yes, only one-time use solution destroys microfilariae. Regarding the treatment of animals with cardiopulmonary form illness, then it is much more complicated. Microfilariae in this case are destroyed by Levamisole or Ivermectin. This is usually enough for the larval stage of the disease.

There are cases when these drugs are also used to destroy mature worms when they threaten the health of an exhausted animal. But, if you kill all the adult worms at the same time, what remains of them can provoke a deterioration in the dog’s well-being. Always determine treatment and necessary medications To get rid of the problem that has arisen, there must be a competent specialist with certain experience. After all, drugs contain toxic arsenic compounds.

Drugs for dirofilaria in dogs

Of the most applicable drugs, Immiticide should be noted. The product is effective in killing adult worms. But it is contraindicated in animals with kidney, liver, heart and lung diseases. In this case, Ivermectin is used for treatment.

Getting rid of helminths is only the first stage in the treatment of this complex ailment. Usually dogs are very weakened and require recuperation. In addition, the internal parts of the body affected by this scourge require certain therapy. Therefore, based on a specific case, a therapeutic plan is developed for each dog in accordance with the type of disease and its severity. Dog owners need to be patient, because treatment can take a long time. for a long time and be difficult.

As sad as it may be, it happens that when neglected form It is impossible to save a dog with an illness. This is especially observed when nematodes attack the heart and lungs. Dog owners should understand that the situation with dogs affected by nematodes of this type cannot be taken lightly. Relying on your own knowledge and wasting time can lead to the death of your pet.

Can the owner get sick?

This question often worries dog owners. A reservation should be made right away, since helminth larvae are transmitted by mosquitoes, dogs cannot be carriers of the disease, and it is impossible to get infected from them. Once upon a time, people could catch this ailment by visiting places with a humid and hot climate. This is where there are usually a lot of mosquitoes. But the insects that carry this dangerous disease, now, unfortunately, can be found in areas with a temperate climate.

IMPORTANT! A sick animal does not pose any threat to the health of the owner. You can safely look after your pet. A person can become infected with heartworms from mosquitoes that carry their larvae. In this case, he is usually affected by the subcutaneous form of the malaise.

Dirofilariasis in dogs - dangerous disease. Those who want not to lose their pet should always remember this.

Prognosis and prevention

Some owners, before going out with their dog for a walk, always treat its fur with mosquito repellent spray, which they themselves use. And they do the right thing. Who knows what could happen during a walk or trip with a pet into nature.

It also doesn’t hurt to constantly use drugs like “Advocate”, which allow you to destroy nematodes even in the microfilariae stage. Another remedy for dirofilaria called “IN-AP complex” has appeared on the market. It should be applied to the animal’s skin at the beginning of summer, and then the treatment should be repeated every 6-7 weeks. The product is well absorbed into the blood and, once there, destroys the larvae of heartworms.

It is possible that many who have encountered this pathology in a pet ask themselves questions: is it possible to completely cure dirofilariasis, is there any point in spending money on such an expensive treatment and suffering yourself, as well as torturing the animal? Such doubts are well founded.

The prognosis for this disease is always positive if timely application behind veterinary care And correct positioning diagnosis. In this case, there is no need to spare money and effort to get your pet back on its feet. After all, this animal is often a full member of the family for many. And returning it to normal life will be a gift not only for him, but also for his owner, to whom he will respond for his care with even greater love and devotion. Always be attentive to your four-legged friend, and then he will not be afraid of any illnesses, including dirofilariasis.