Durability of ChAdOx1 nCoV-19 (Covishield ® ) Vaccine Induced Antibody Response in Health Care Workers

• Published in: Vaccines (Basel) Vol. 11; no. 1; p. 84
• Main Authors: Verma, Alka, Goel, Amit, Katiyar, Harshita, Tiwari, Prachi, Mayank, Sana, Asari, Khetan, Dheeraj, Bhadauria, Dharmendra Singh, Raja, Ajay, Khokher, Neelam, Shalimar, Singh, Ratendra Kumar, Aggarwal, Amita
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 30-12-2022; MDPI
• Subjects: Acids; Anti-SARS-CoV-2 antibody; Antibodies; Antibody response; Asymptomatic; coronavirus; Coronaviruses; COVID vaccine; COVID-19; COVID-19 vaccines; Covishield; Drug dosages; Durability; Health care; Infections; Medical personnel; neutralising antibody; Pandemics; Serology; Severe acute respiratory syndrome coronavirus 2; Vaccination; Vaccines; India; COVID-19; coronavirus; Anti-SARS-CoV-2 antibody; Covishield; neutralising antibody; COVID vaccine
• ISSN: 2076-393X; 2076-393X
• DOI: 10.3390/vaccines11010084

(i) Background: ChAdOx1 nCoV-19 (Covishield®) vaccine is widely used in India. We studied the Covishield® induced antibody response and its durability among health care workers (HCWs) (ii) Method: HCWs received two doses (0.5 mL) four weeks apart. Blood specimens, collected before each dose, day (D)60, D150 and D270 after second dose, were tested for anti-spike antibody (ASAb) titre and neutralising antibody (%) (NAb) using Elecsys Anti-SARS-CoV-2 S (Roche) and SARS-CoV-2 NAb ELISA Kit (Invitrogen), respectively. Data are expressed as proportions and median (interquartile range) and compared using non-parametric (iii) Result: Among 135 HCWs (83 males; age 45 (37−53); 36 had pre-existing ASAb), 29 (21.5%) acquired COVID-19 after 60 (39−68) days of vaccination. ASAb titre before second dose and at D60, D150, D270 were 77.2 (19.4−329.4), 512 (114.5−9212), 149 (51.6−2283) and 2079 (433.9−8644) U/mL, respectively. Compared to those without pre-existing ASAb, titres were significantly higher before second dose (5929 vs. 41, p < 0.001), D60 (3395 vs. 234, p = 0.007) and D150 (1805 vs. 103, p < 0.001) in participants with pre-existing ASAb; NAb were also higher (80 vs. 18, p < 0.001) before second dose. Between those who acquired infection or not after vaccination, ASAb titres were comparable before second dose (77 vs. 78, p = 0.362) but significantly higher at D60 (14,019 vs. 317, p < 0.001) and D150 (2062 vs. 121, p = 0.002) in the former group, though NAb percentage were higher at D60 (87 vs. 27, p < 0.001) and D150 (79 vs. 25, p = 0.007) only (iv) Conclusions: Covishield® induces a higher antibody titre in those with pre-existing ASAb. The vaccine induced antibody starts falling 5 months after vaccination.