**6. Incorporation of viral components into EVs**

Accumulating experimental evidence suggest viral components are packaged in EVs during infection and this results in alterations within recipient cells. Virus proteins including nucleoproteins and glycoproteins packaged in EVs were found to induce apoptosis in recipient immune cells.

One study reported the presence of ebola virus VP40, nucleoprotein, and glycoprotein in EVs that leads to apoptosis in recipient cells [30]. Studies by the same group also showed that VP40 can become incorporated into exosomes and thereby negatively impact recipient T cells and monocytes [30–32]. Multiple groups showed Zika virus infected cells release EVs with infectious viral RNA and viral proteins [33, 34]. York et al. showed that Zika virus modifies EV density, cargo, and secretion [33]. Ning et al. showed RNA from SARS-CoV-2, the causative agent of Severe Acute Respiratory Syndrome, COVID-19 in plasma EVs just one day after infection which plateaued from day 6–28 in non-human primates and 20–60 days in young children [35]. In another study, Troyer et al. showed EVs released from cells expressing the CoV-2 spike protein contain multiple peptides originating from this protein [36]. This group reported EVs carrying these spike proteins can serve as a decoy for anti-spike neutralizing antibodies and therefore promote viral infection.

The pathogenic and deleterious effect of EVs containing viral components is not limited to acute disease but it can result in asymptomatic or recurrent infections. The delivery of various molecules packaged in EVs and the delivery of these EVs to healthy cells may allow the virus to remain latent.
