Science has made a huge leap that will allow us to better understand babesia, a Potentially deadly parasite increasingly present in Spain. A team from the National Microbiology Center of the Carlos III Health Institute participated in the international investigation that revealed the first complete sequence and 3D structure of the pathogen's genome Babesia duncanithe causative microorganism babesiosis, a disease similar to malaria. The results of this study, coordinated by the universities of Yale and California, in the United States, have just been published in the journal Nature Microbiology.
Babesiosis is a disease that affects humans and animals, including dogs. It is usually transmitted by the bite of a type of tick. Babesia enters the bloodstream and enters red blood cells (erythrocytes), where it matures and divides, causing the erythrocytes to rupture. Specifically, the microorganism studied ('Babesia duncani') causes a particularly severe babesiosis that can be lethal in infected people. The symptoms of this infection can be mild, but they can also become complicated and cause very high fevers and the failure of several organs, which can even cause death.
Estrella Montero, Luis Miguel González and Sergio Sánchez, researchers at the CNM-ISCIII Reference and Research Laboratories in Parasitology and Bacterial Infections Transmitted by Water and Food and co-authors of the article, explain that the research reveals for the first time the genome of this parasite, its nuclear structure, its transcriptomic and epigenetic profiles, how its genetic material is assembled, its three-dimensional molecular structure and its phylogenetic evolution.
Until now, and despite the high pathogenicity of 'Babesia duncani', there was very little information about its biology, evolution, virulence mechanisms, pathogenicity and drug susceptibility. The discoveries now achieved, including the discovery of new multigene families developed by the parasite to escape the human immune response, allow you to refine the diagnosis of the infectionbetter select available medicines, improve testing of other medicines in development and facilitate the search for new therapeutic targets for infection in humans.
Through an in vitro analysis with human erythrocytes, in an animal model, the authors developed a 'map' of the parasite's metabolism and its development during infection. This atlas of new data provided new knowledgein the form of antigens, for the diagnosis of active infection and molecules for the possible development of drugs, such as antifolates, including pyrimethamine, which inhibit the infectious action of Babesia duncani and may be effective in treating babesiosis in people.
Incidence of human babesiosis in Spain
Human babesiosis is still a rare zoonosis in Spain, but its incidence rate has been increasing over the years. This is what another study led by specialists from the Salamanca University Hospital reveals, published on February 2 this year in the journal PLOS One. The work states that there is no complete global incidence in the literature, although the United States, Europe and Asia are considered endemic areas.
The study analyzed the evolution of the parasite specifically in our country over 23 years. Between 1997 and 2019, 29 patients hospitalized with babesiosis were identified in Spain. 82.8% of the cases corresponded to urban men aged approximately 46 years between summer and autumn.
The regions of Castilla-La Mancha and Extremadura recorded the highest number of cases. Given the low rate of primary diagnoses (55.2%) and the high number of readmissions (79.3%), there is likely to be low clinical suspicion. The study points out that the mortality rate is estimated at approximately 9% in hospitalized patients, but can reach 20% if the disease is transmitted by transfusion of contaminated blood.
To treat mild or moderate babesiosis, broad spectrum antibiotics, such as azithromizine, and antiprotozoal drugs, such as atovaquone. In cases of severe infection, quinine and clindamycin are indicated in combination with other treatments and exchange transfusion.
Symptoms of Babesiosis
Symptoms usually appear one to four weeks after being bitten by an infected tick or one week to six months after receiving a contaminated transfusion. Symptoms of Babesiosis include: high fever, headache, chills, joint pain, muscle pain, fatigue from hemolytic anemia, jaundice or enlarged liver and spleen.
In dogs, Babesiosis produces a clinical picture characterized mainly by febrile syndrome and hemolytic anemia. The animal has a fever and weakness. There is treatment, but its effectiveness depends on factors such as the age of the animal or the time that has passed since the bite.
