Metagenomic approach to assess viral factors potentially involved in vertical transmission of CHIKV.
This study aimed at assessing the intrahost genetic diversity of CHIKV in infected patients with neurological manifestations and in mothers infected during the intrapartum period with a concomitant vertical transmission to their newborns, in order to determine whether particular viral variants could be correlated with atypical manifestations potentially involving barriers such as the placenta.
Results are suggestive of a potential bottleneck in the transmission from the mother to its foetus, which could indicate that virus passage through the placenta barrier is not an active and constant process. Consistent with the literature, the most suitable current explanation seems to be the collateral placental damage due to the host inflammatory response. It should be better explored, however, if the presence of potential defective particles or replicative defective viral particles, as reported here, could influence this response, ultimately triggering a more compromised immune response that facilitates the vertical transmission.