Filaria is a pathology transmitted by blood-sucking mosquitoes – those that feed on blood – to dogs, cats and humans, and whose presence is greater in the Islands than in the rest of the national territory due to causes associated with the weather. Taking this into account, and according to the expert’s words, “it is not the dog that is responsible for the infection, but the mosquito that has infected a sick dog and that later bites the human.” This is when an allergic process can be triggered.
Following this line, during the research patients suffering from rhinitis, asthma and allergic dermatitis were evaluated. The next step was to study the level of immunoglobulin E – which indicates the presence of an allergic disease – in these subjects. “All patients with high immunoglobulin E were positive for heartworm disease,” added the study director. “We know that there is a correlation between these data,” he continued, “and although they do not exactly determine causality, they give us many clues to continue studying.”
As indicated by Professor Montoya, it was precisely the high rate of allergy sufferers in the Canary Islands, in contrast to that found in the peninsular territory, which prompted the group to start the analysis. “It must be said that in 2018 we carried out an investigation in which we implicated 1,479 inhabitants of the Islands, of which 9% showed antibodies against heartworm,” he emphasized. A fact that encouraged scientists to continue studying in depth.
In the professor’s opinion, the data is very striking, but the most important thing for the experts has been precisely to demonstrate the relationship between the factors that contribute to the development of allergies in the Islands and the filaria.
Now, the challenge set by the team is focused on performing more accurate determinations. “A medical study should be carried out on sick patients to be able to determine the type of allergy that other owners of infected dogs may develop, the allergens that are involved and verify the exact relationship with the filaria,” said the professor.
The Canary Islands are an ideal place for mosquitoes to breed due to their climatic conditions, the study experts say.
The truth is that the Archipelago is an ideal environment for the reproduction of all mosquitoes in general. “They tend to live in places where the temperature exceeds 18º throughout the year and where there is a lot of humidity. The Islands meet these requirements, hence the prevalence of filaria is so high “, Montoya determined.
For this reason, remember that the best way to avoid the spread of this zoonotic disease – which is transmitted between animals and humans – is to monitor the health of pets. “The owners must be responsible enough to apply the necessary treatments to their dogs to avoid the spread of this disease, as it can be fatal for the animals due to the pulmonary and cardiac complications that it causes. Only with a pill a month or an injection a year can be prevented ”, said the expert.
Professors have participated in this research directed by the professor of the ULPGC Jorge Isidoro Matos, Yaiza Falcón, Noelia Costa and Elena Carretón, by the same educational institution, and the professor of the Parasitology area of the Department of Animal Biology at USAL, Rodrigo Morchón.
Last year, the same group developed a study, which was published in the renowned journal Veterinary Parasitology, and that it evidenced the possibility of reducing the treatment to combat filaria in dogs to two months. At present, after having demonstrated efficacy, they continue to apply the therapy to all the dogs they treat.
A bet for the future
Heartworm is a disease caused by a species of nematode –worm– that is transmitted to dogs, and less frequently to humans and cats, through the bite of a mosquito. However, in the case of dogs, the pathology can cause devastating effects, including respiratory and cardiac complications and even death itself. There are numerous open investigations in this field. Now, the one directed by the professor of the ULPGC José Alberto Montoya and financed by the Government of the Canary Islands aims to demonstrate the link that exists between canine filariasis and the development of allergies in owners. “Developed countries dedicate a large part of their Gross Domestic Product – GDP – to research in order to draw conclusions and prosper. Investing in research is investing in the future ”, assesses the director of the study. Likewise, aware that at present it is the global Covid-19 pandemic that occupies all the attention of the experts, he does not hesitate to assure that “there are other diseases that existed long before and that also require progress.” In this sense, it guarantees that, during this period, its line of work has achieved great progress in terms of treatments, diagnoses and prognoses. “We are managing to advance the knowledge we have about zoonotic pathologies and, for this, it is essential to invest capital. For this reason, I believe that the money contributed by the Canarian Government to our study has been profitable, “he says.