Sara Martín-Gromaz Esteban defended this Degree Final Project

September 19^th, 2024

The Toscana Virus (TOSV) is an arbovirus of the genus Phlebovirus, which is transmitted by the bite of phlebotomine sandflies of the genus Phlebotomus and is currently considered an emerging zoonotic pathogen. This virus is known to cause meningitis in humans in endemic areas of the Mediterranean, especially during the summer months when there is increased phlebotomine sandfly activity. Recent studies suggest that some mammals, including lagomorphs, could act as reservoirs or potential amplifying hosts of the virus in certain regions.
In addition, co-infection with Leishmania, which is transmitted by the same dipteran insects, has been demonstrated. In Spain, previous studies indicate that TOSV circulates in different regions and there have been clinical cases in humans. On the other hand, it has been demonstrated that phlebotomine sandfly vectors are widely distributed in our country and bite hares and rabbits. Therefore, the aim of the present study was to analyze the presence of TOSV in samples of rabbits from the Community of Madrid, to check if they are infected by this microorganism and could be a potential reservoir for it, as has been demonstrated with leishmaniasis in this region. A total of 142 cerebrospinal fluid (CSF) samples obtained from rabbits from different locations in the Autonomous Community of Madrid were analyzed. A real-time PCR technique targeting the N gene of the virus was used to detect the presence of the virus. The results obtained indicated that none of the rabbit CSF samples tested were positive.
These results suggest that TOSV is not circulating in the rabbit population studied. This could be because this population is not infected with TOSV. However, it could also be because the virus has not replicated in the CSF sample and/or its duration in the CSF sample is very short and could not be detected at the time of sampling. Therefore, the possible previous exposure of rabbits to the virus cannot be ruled out, highlighting the importance of combining molecular methods with seroprevalence studies to achieve a complete assessment of the real situation to rule out virus circulation. For this reason, and due to the proven presence of TOSV and vectors in our country, and the confirmation of clinical cases in humans in the region, surveillance work
should continue and studies should be expanded. In this way, control strategies can be imposed
if necessary, limiting the risk of transmission of this phlebotomine sandfly-borne disease
associated with co-infection with Leishmania.
Keywords: Toscana Virus, RT-PCR, seroprevalence, rabbit, phlebotomus