Rocky Mountain spotted fever: tick protein is target of a future vaccine

A protein found in the star tick that transmits the disease, Potential target for development of a vaccine against Rocky Mountain spotted fever. Discovery published in the journal Parasites and Vectors and published this Wednesday (14), is part of a study led by researchers from the University of São Paulo (USP).

The protein in question (IAP) has the ability to inhibit a process called apoptosis, which consists of the programmed death of arachnid cells, which promotes the growth of bacteria. Rickettsia rickettsii, causing disease. With this “survival”, the infectious agent gains time to infect new cells.

In the study, the authors tested silencing of IAP gene expression as a way to reduce bacterial growth and increase tick resistance to infection. For this purpose, blood from infected and uninfected rabbits was used. rickettsia to feed the host.

The result was promising, The death rate in star ticks of the experiment was over 92%. According to study coordinator Andréa Cristina Fogaça, data show that arthropod feeding produces free radicals that can activate apoptosis and cannot survive when IAP is silenced, reducing the incidence of Rocky Mountain spotted fever transmission.

deaths in Sao Paulo

Adolfo Lutz Institute Two more deaths were confirmed from Rocky Mountain spotted fever in São Paulo state on Tuesday (13). In addition to these, a third person died last week as a result of the infection – all attending the same event on a farm in the rural area of ​​Campinas (SP).

Headache, high and sudden fever, abdominal and muscle pains are the main symptoms of the disease, which can manifest itself with skin rashes in the area where the star tick bites. It is necessary to seek urgent medical care to prevent worsening of the condition, as its symptoms are confused with those of other diseases.

illness is treated with the use of antibiotics and has a cure, but the death rate in the country is 28%. According to the Ministry of Health, about 160 cases per year have been recorded on average across Brazil, taking into account the last three years.

With regard to research that could lead to the development of a vaccine against Rocky Mountain spotted fever, next steps are to confirm that the blood supply is a facilitator of apoptosis and expand testing to other tick species. According to the research leader, the vaccine will also have positive effects on livestock.