Novel Viruses Found in Antricola Ticks Collected in Bat Caves in the Western Amazonia of Brazil

Abstract

In this study, we describe the viral composition of adult Antricola delacruzi ticks collected in a hot bat cave in the state of Rondônia, Western Amazonia, Brazil. A. delacruzi ticks, are special, compared to many other ticks, in that they feed on both bats (larval blood feeding) and bat guano (nymphal and adult feeding) instead of feeding exclusively on vertebrate hosts (blood feeding). Considering this unique life-cycle it is potentially possible that these ticks can pick up/be infected by viruses not only present in the blood of viremic bats but also by virus shed through the bat guano. The viral metagenomic investigation of adult ticks showed that single-stranded negative-sense RNA viruses were the dominant group of viruses identified in the investigated ticks. Out of these, members of the Nairoviridae family were in clear majority constituting 88% of all viral reads in the data set. Genetic and phylogenetic analyses indicate the presence of several different orthonairoviruses in the investigated ticks with only distant relationship to previously described ones. In addition, identification of viral sequences belonging to Orthomyxoviridae, Iflaviridae, Dicistroviridae, Polycipiviridae, Reoviridae and different unclassified RNA viruses showed the presence of viruses with low sequence similarity to previously described viruses.

Sequence diversity and evolution of a group of iflaviruses associated with ticks

“…This suggests an ancient association between this virus subgroup and ticks, which could mean relatively infrequent host switches of the virus between major groups of arthropods. It is noteworthy, however, that two iflavirus-like genome sequences have been described recently in members of the genus Antricola [ 28 ], a genus of neotropical soft ticks that have a peculiar biology, being associated with hot bat caves and feeding partially on bat guano instead of having an exclusive vertebrate blood diet. These two sequences (not included in our phylogeny) grouped closely with insect iflaviruses and not with sequences associated with ticks, showing that there has been more than one infection of ticks by viruses of this family.…”

Evaluation of Viral RNA Recovery Methods in Vectors by Metagenomic Sequencing

“…Evaluating and optimizing efficient viral NA extraction methods is thus crucial for mNGS analysis. Various commercial and non-commercial extraction methods have been used for recovery of NA from ticks and mosquitoes [26][27][28][29][30][31][32].…”

Sequence diversity and evolution of an iflavirus family associated with ticks

“…This suggests an ancient association between this virus sub-group and ticks, which could mean relatively infrequent host-switches of the virus between major groups of arthropods. Of note however, two iflavirus-like genome sequences have been recently described for the Antricola genus [28], a genus of neotropical soft ticks which have a peculiar biology, being associated with hot bat caves and partially feeding on bat guano instead of an exclusive vertebrate blood diet. These two sequences (not included in our phylogeny) grouped closely with insect iflaviruses and not with sequences associated with ticks, showing that there has been more than one infection of ticks by this family of viruses.…”