Table 10.
Comparison of the sensitivity and specificity of IFA in detecting different targets of MERS-CoV and SARS-CoV-2.
| Virus type | Targets/Sources of samples | Sensitivity (SN) | Specificity (SP) | References |
|---|---|---|---|---|
| MERS-CoV | S | 3/10 (30%) for IgM compared to 9/10 (90%) compared to IgG | Varied due to cross-reactivity with other pathogens in sera of different patients (<100%) | [192]; |
| Whole virus | 100%; | 0–83% (depending on cross-reaction with different pathogens) | [193] | |
| Infected cells | ~97.9% at <1:20 dilution | 25% of SARS-CoV patients had anti-MERS-CoV antibody reactions | [194] | |
| Unclear | Detection rate of MERS-CoV = 38% compared to detection rate of MERS-CoV using ELISA = 30% (comparable results | Unclear | [195] | |
| SARS-CoV-2 | S | 85.7–96.3% (IgG) | High (unclear on the values) | [199] |
| Inactivated infected cells | Unclear | ~100% (IgG) | [197] | |
| Inactivated infected cells | 76.5–100% (IgG) | 86.4% (IgG) | [196] | |
| Inactivated infected cells | 41.9 (IgG), 35.5% (IgM) | Unclear | [183] | |
| Inactivated infected cells | 99% (IgG) | 100% (IgG) | [198] | |
| Inactivated infected cells | 41% (IgG) | 93% (Ig G), 98.5–100% (IgM/A) | [184] | |
| Virus from patient sera | 91.3% (IgG/A/M) (at Day 14 after onset of symptoms) | 98.9% (IgG/A/M) (at Day 14 after onset of symptoms) | [327] |