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#Oropouche virus infects primary #human #intestinal #organoids and is inhibited by type I and III interferon treatment

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By G.M.

 


ABSTRACT

Oropouche virus (OROV), a neglected arbovirus, has historically been considered a self-limiting infection associated with febrile illness. However, the recent surge in cases since late 2023 has been marked by atypical outcomes, highlighting its underestimated clinical impact. Gastrointestinal symptoms such as diarrhea have also been reported, but the prevalence and mechanistic insight remain largely elusive. Here, through a meta-analysis of 12 identified clinical studies, we revealed a pooled prevalence of diarrhea as 15% (95% CI, 10%–20%) among the Oropouche patient population. In primary human intestinal organoid-based experimental models, we demonstrated productive infection by both a recent patient isolate (OROV-2024) and a historical strain (Be An19991). This is shown by the accumulation of intracellular OROV RNA, release of infectious particles, and immunostaining of OROV glycoprotein Gc. Interestingly, OROV infection mildly triggered the expression of type III interferons, but this endogenous response was insufficient to limit viral replication. In contrast, exogenous treatment with type I and III interferons strongly inhibited OROV replication, with interferon-alpha completely abolishing infectious virus production. Together, these results suggest the human intestine as a potential target organ for OROV infection and highlight interferons as potential therapeutic candidates.

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Link: https://journals.asm.org/doi/full/10.1128/mbio.03003-25?af=R

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