Table 1.

Summary of ESN findings for SARS-CoV-2 and other viruses.

	SARS-CoV-2	Other
Canonical immune response	Both humoral and cellular immunity weeks after infection. Resolution usually within weeks with a small percentage experiencing severe or fatal outcomes.	HCV: Adaptive immunity months after infection. Cellular immunity with some contribution from neutralising antibodies.
Exposure duration and dose	Prolonged exposure not essential. Duration of exposure required is unclear.	HCV: Ongoing or recent exposure important for response maintenance. Potential role for low doses of virus. Responses peak earlier than in seropositive infection.
Durability	Unknown	HCV: Limited, with waning of responses observed within one year
Target antigens	Early translated antigens More non-structural targets than seropositive individuals	HCV: Early life cycle peptides
Cytokine profile	IL-2, IFNγ in some cases but not always	HBV: IFNγ production EBOV: IFNγ production
Potential source of response	Cross-reactivity with HCoVs	MERS: Potential cross-reactivity with HCoVs