Animals are not to blame for Rocky Mountain spotted fever – 06/15/2023 – Health

At the beginning of the Mpox (monkey pox) health emergency, five monkeys were found dead in the interior of São Paulo. The suspicion was that ill-informed residents had poisoned the animals to avoid the disease, as if it were their fault.

Currently, with the outbreak of spotted fever in the region of Campinas (93 km from the capital of São Paulo), health authorities fear the same, mainly with the capybara, the main carrier of the star tick, which transmits the disease when infected by the bacteria Rickettsia rickettsii.

According to Marcello Schiavo Nardi, a veterinarian at the São Paulo City Hall’s Wildlife Division, many animals can be carriers of star ticks and it’s not their fault. The culprit, he points out, is man himself, who destroyed the original forest and caused capybaras to enter urban areas.

“This relationship between man and the environment favored one species over others. Capybaras are benefiting from our lifestyle. We created conditions for them, with sugarcane and corn plantations alongside rivers, which is their natural habitat. The condominiums have also become an oasis. There are no predators and a lot of grass. That’s why the capybaras end up proliferating. Anyway, we changed everything and we have to know how to deal with it”, highlights Nardi.

Veterinarian Alessandra Nava, a zoonoses researcher at Fiocruz Amazônia, agrees. She claims that the end of the Atlantic forest cover in the Campinas region is the main reason why Rocky Mountain spotted fever still causes victims in Brazil. That’s because it ended the balance of the biome, eliminating the population of jaguars, the natural predators of capybaras.

“This disease occurs because there is an imbalance in biodiversity. This protection that the forest provides us is no longer there and there is an animal left that is resilient and that, unfortunately, has this ability to, if it has the bacteria, be a great amplifier of the disease “, says Nova. “In the North and Northeast there are no cases, but every year there are morbidities in the regions of Campinas, Piracicaba and Americana. And what is there in the Amazon that is no longer there? The forest. -of sugar.”

The São Paulo City Hall veterinarian explains that there are three types of star ticks in the country. The one from the region of Campinas, the Amblyomma sculptum, in the immature form, it is generalist and can parasitize several hosts, including birds. But the adult, which closes the cycle, originally parasitizes tapirs. And as the tapir is almost extinct, the Amblyomma sculptum ended up adopting the capybara as the primary host.

And although capybaras are not to blame, the two specialists agree that their population needs to be controlled in urban centers. “It’s a bit cruel to think about killing capybaras, because it’s a situation that we created and we have the knowledge to prevent it from happening. We can control it with sterilization in a more ethical, more humane way. the most truculent, cruel way”, says Nardi.

Dogs are the carriers in Greater São Paulo

Marcello Nardi explains that in the metropolitan region of São Paulo the cycle of Rocky Mountain spotted fever is different from that seen in the countryside. In the capital, what is verified is the Amblyomma aureolatum, a wild carnivore tick. But dogs also enter this cycle as hosts, he warns.

“O Amblyomma aureolatum it is a tick from the mountainous region of the atlantic forest, so the dog became the main problem. He goes to the woods and comes back, and people end up getting infected at home. The one you catch walking in the woods, like in Campinas, is the tick sculptum, which parasitizes capybaras, but can also parasitize horses and possums.”

In a note to the report, the City of São Paulo, through the Secretariat for the Green and the Environment, informs that so far there are no cases of transmission of spotted fever in capybaras in the capital. She advises citizens to avoid feeding wild animals and keep their distance from them and their young.

The Municipal Health Secretariat, through Covisa (Health Surveillance Coordination), says that since 2021 there have been no autochthonous cases – those contracted in the resident’s city of residence – in Greater São Paulo. “In relation to deaths, in the year 2022, an imported death was recorded (municipality Santa Branca-SP) and, in 2023, an imported death (Campinas-SP)”, informs the note.

Doctors demand health education for the population

For Marcello Nardi and Alessandra Nava, deaths from Rocky Mountain spotted fever only occurred due to lack of knowledge on the part of the victims and also of the professionals who treated them and were unable to identify the disease immediately.

“If you walk in a forested area, you have to be aware that there are ticks and that you can get the disease. Many times people get it and don’t know it, and they go to the doctor and the doctor doesn’t know either. As it doesn’t happen that often, doctors don’t wait [a doença]. Therefore, the person has to go and say that he was in a forest area. The disease is curable and easy to treat, but it has to be identified”, says Nardi.

“We have to make a reception in our health system to remember that this disease is still circulating. If these people had been properly medicated for maculosa, they could be alive. It is the doctor taking anamnesis and asking: Where did you go? tick?”, completes Nava.

If you have contact with forest regions, follow some tips

• Wear light-colored clothes, boots and pants inside the sock with a ribbon closing it, to prevent the entry of the tick;
• Carry out inspections of the body from time to time, using a roller or tape with glue to remove the parasites;
• Use repellents that inhibit ticks;
• At home, clean clothes in boiling water after use;
• If you have direct contact with ticks, avoid removing them with your hands, use tweezers;
• Avoid walking with dogs in wooded areas, unless they are vaccinated and walking on a leash;
• Even so, it is then necessary to inspect the animal, to see if it has not caught ticks.