IRB PhD student Tomás Cervantes Rincón and colleagues in the United States, Mexico and Brazil discover evidence of a tick-borne Flavivirus transmitted to humans in tropical regions. The new study, published in Cell Reports, prompts future investigations to identify such virus and its relevance for human disease.
Bellinzona, June 25, 2024 – Mosquitoes are known to transmit viruses in tropical regions of the Americas, Africa and Asia. Among these, are Flaviviruses that cause important human diseases like de ngue and Zika. Additionally, in temperate regions of the northern hemisphere, ticks can transmit different sets of Flaviviruses that cause brain infections (such as tick-borne encephalitis and Powassan disease).
In a collaborative project led by the groups of Davide Robbiani at the Institute for Research in Biomedicine (IRB, affiliated to Università della Svizzera italiana) and Peggy MacDonald at Rockefeller University (New York), scientists identified—in individuals living in tropical regions—antibodies capable of neutralizing tick-borne flaviviruses.
“It came as a surprise” says immunologist Davide Robbiani “antibodies carry the memories of pathogens that we were previously exposed to. Evidence for infection by Flaviviruses transmitted by ticks had not been reported before in these regions of the world”. Virologist Peggy MacDonald adds “The importance of Flaviviruses for human disease is exemplified by the largest ever recorded outbreak of dengue that was until recently raging in Brazil, and by the damage that Zika infection can cause to unborn babies. New studies should investigate whether, in addition to mosquitoes, ticks could also be a source of Flavivirus disease in the same regions.”
Flaviviruses are on the rise in Europe. Flaviviruses transmitted by ticks have caused increasing numbers of human infection in recent years, while local outbreaks by mosquito-borne Flaviviruses (dengue and West Nile virus) were already reported in Southern Europe, probably favored by higher temperatures that promote the spread of mosquitoes.
The new study was supported by several agencies, including the Swiss National Science Foundation, the US National Institutes of Health, and the IRB-Rockefeller University partnership for infectious disease research.
Photo (from left): Tomás Cervantes Rincón and Jasmine Oberti-Cantergiani
