Table 2.
Humoral immune responses pre- and post-vaccination among recipients of quadrivalent inactivated egg-based influenza vaccine (IIV4) and quadrivalent recombinant influenza vaccine (RIV4) measured by hemagglutination inhibition assay against influenza vaccine reference viruses a, Israel, 2019-2020.
| Hemagglutination inhibition assay outcome measuresb | IIV4 n = 212 |
RIV4 n = 203 |
RIV4 vs IIV4 Post-Vaccination |
P-value | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pre-vaccination | Post-vaccination | Pre-vaccination | Post-vaccination | Difference (95% CI) | GMT ratio (95% CI) | ||||||||
| Influenza A(H1N1)pdm09 | |||||||||||||
| GMT (95% CI) | 44.1 | (38.1-51.1) | 82.9 | (71.6-96.1) | 44.5 | (38.2-51.7) | 178.4 | (153.5-207.5) | 2.0 | (1.7-2.7) | <0.001 | ||
| Mean-Fold Rise (95% CI) | 1.9 | (1.5-2.3) | 4.0 | (3.2-5.0) | |||||||||
| Seroconversion, % (95% CI) | 23.8 | (18.2-29.5) | 52.8 | (46.1-59.5) | 29.0 | (20.1-37.8) | |||||||
| GMT ≥40, % (95% CI) | 68.4 | (62.1-74.7) | 87.3 | (82.8-91.4) | 67.0 | (60.5-73.5) | 95.6 | (92.7-98.4) | 8.3 | (3.0-13.6) | |||
| GMT ≥160, % (95% CI) | 20.8 | (14.9-25.5) | 38.9 | (32.4-45.4) | 20.6 | (15.1-26.0) | 66.3 | (59.8-72.7) | 27.3 | (18.2-36.5) | |||
| Influenza A(H3N2), Egg-based | |||||||||||||
| GMT (95% CI) | 62.4 | (54.7-71.2) | 152.8 | (133.9-174.3) | 60.3 | (52.7-69.0) | 246.9 | (215.8-282.5) | 1.6 | (1.3-1.9) | <0.001 | ||
| Mean-Fold Rise (95% CI) | 2.4 | (2.0-2.9) | 4.1 | (3.4-5.0) | |||||||||
| Seroconversion, % (95% CI) | 34.8 | (28.4-41.3) | 57.2 | (50.5-64.0) | 22.4 | (13.1-31.8) | |||||||
| GMT ≥40, % (95% CI) | 84.0 | (79.0-88.9) | 97.2 | (94.9-99.4) | 75.9 | (70.0-81.8) | 97.5 | (95.4-99.7) | 0.37 | (−2.7-3.5) | |||
| GMT ≥160, % (95% CI) | 26.2 | (20.4-32.0) | 63.4 | (57.1-69.7) | 29.2 | (23.1-35.3) | 80.2 | (74.8-85.5) | 16.7 | (8.5-25.0) | |||
| Influenza A(H3N2), Cell-based | |||||||||||||
| GMT (95% CI) | 30.7 | (27.2-34.6) | 80.8 | (71.6-91.1) | 31.1 | (27.5-35.2) | 189.2 | (167.3-214.0) | 2.3 | (2.0-2.8) | <0.001 | ||
| Mean-Fold Rise (95% CI) | 2.6 | (2.2-3.1) | 6.1 | (5.1-7.2) | |||||||||
| Seroconversion, % (95% CI) | 41.0 | (33.9-47.1) | 77.4 | (71.8-83.0) | 36.9 | (28.3-45.6) | |||||||
| GMT ≥40 (95% CI) | 56.1 | (49.5-62.8) | 88.2 | (83.9-92.6) | 58.6 | (51.9-65.4) | 96.1 | (93.4-98.7) | 7.9 | (2.8-13.0) | |||
| GMT ≥160 (95% CI) | 2.5 | (0.4-4.6) | 30.6 | (24.4-36.8) | 3.7 | (1.1-6.3) | 65.8 | (59.3-72.3) | 34.9 | (25.8-43.9) | |||
| Influenza B(Victoria) | |||||||||||||
| GMT (95% CI) | 54.0 | (46.7-62.3) | 78.3 | (67.9-90.4) | 48.5 | (41.9-56.2) | 90.3 | (78.0-104.6) | 1.1 | (0.9-1.4) | 0.175 | ||
| Mean-Fold Rise (95% CI) | 1.5 | (1.2-1.8) | 1.9 | (1.5-2.3) | |||||||||
| Seroconversion, % (95% CI) | 9.0 | (5.3-13.0) | 18.0 | (12.7-23.3) | 8.9 | (2.3-15.5) | |||||||
| GMT ≥40, % (95% CI) | 70.7 | (64.5-76.8) | 83.0 | (77.8-89.7) | 67.1 | (60.6-73.6) | 82.9 | (79.7-89.7) | 1.8 | (−5.4-9.0) | |||
| GMT ≥160, % (95% CI) | 24.2 | (18.5-29.9) | 34.0 | (27.4-40.1) | 19.9 | (14.4-25.4) | 40.1 | (33.4-46.9) | 6.4 | (−2.9-15.7) | |||
| Influenza B(Yamagata) | |||||||||||||
| GMT (95% CI) | 68.7 | (59.7-79.0) | 105.7 | (91.9-121.7) | 71.7 | (62.1-82.7) | 196.2 | (170.0-226.5) | 1.8 | (1.4-2.2) | <0.001 | ||
| Mean-Fold Rise (95% CI) | 1.5 | (1.3-1.9) | 2.7 | (2.2-3.4) | |||||||||
| Seroconversion, % (95% CI) | 14 | (9.3-18.7) | 36.6 | (30.0-43.3) | 22.6 | (14.4-30.8) | |||||||
| GMT ≥40, % (95% CI) | 83.0 | (78.0-88.1) | 90.1 | (86.1-94.1) | 83.7 | (78.7-88.8) | 97.0 | (94.7-99.4) | 7.0 | (2.3-11.6) | |||
| GMT ≥160, % (95% CI) | 31.6 | (25.4-37.8) | 50.0 | (43.2-56.7) | 30.1 | (24.0-36.2) | 67.1 | (60.9-73.4) | 17.2 | (8.0-26.3) | |||
Abbreviations: IIV4, Quadrivalent inactivated influenza vaccine; RIV4, Quadrivalent recombinant influenza vaccine; GMT, Geometric mean titre;
Influenza vaccine reference viruses: A/Brisbane/02/2018 (H1N1)pdm09, A/Kansas/14/2017 (H3N2), B/Colorado/06/2017 (Victoria lineage), and B/Phuket/3073/2013 (Yamagata lineage) vaccine antigens.
GMT, Mean-Fold Rise in GMT, and GMT ratios were calculated using linear mixed models adjusting for age, hospital, and immunocompromised status. Statistically significant differences are shown in bold.