tetano
Editor, Senior Moderator
Clin Infect Dis
. 2022 Apr 19;ciac292.
doi: 10.1093/cid/ciac292. Online ahead of print.
Effectiveness of mRNA COVID-19 vaccines against symptomatic SARS-CoV-2 infections during the Delta variant epidemic in Japan: Vaccine Effectiveness Real-time Surveillance for SARS-CoV-2 (VERSUS)
Haruka Maeda[SUP] 1 2 [/SUP], Nobuo Saito[SUP] 3 [/SUP], Ataru Igarashi[SUP] 4 5 [/SUP], Masayuki Ishida[SUP] 6 [/SUP], Kazuya Suami[SUP] 7 [/SUP], Ai Yagiuchi[SUP] 7 [/SUP], Yuya Kimura[SUP] 8 [/SUP], Masaru Komino[SUP] 8 [/SUP], Hiromi Arai[SUP] 8 [/SUP], Toru Morikawa[SUP] 9 [/SUP], Iori Motohashi[SUP] 10 [/SUP], Rei Miyazawa[SUP] 10 [/SUP], Tetsu Moriyama[SUP] 11 [/SUP], Hiroshi Kamura[SUP] 12 [/SUP], Mayumi Terada[SUP] 13 [/SUP], Osamu Kuwamitsu[SUP] 14 [/SUP], Tomoichiro Hayakawa[SUP] 15 [/SUP], Eiichiro Sando[SUP] 16 17 [/SUP], Yasuji Ohara[SUP] 18 [/SUP], Osamu Teshigahara[SUP] 19 [/SUP], Motoi Suzuki[SUP] 20 [/SUP], Konosuke Morimoto[SUP] 1 [/SUP]
Affiliations
Abstract
Background: Although high vaccine effectiveness of messenger RNA (mRNA) coronavirus disease 2019 (COVID-19) vaccines was reported in studies in several countries, data is limited from Asian countries, especially against the Delta (B.1.617.2) variant.
Methods: We conducted a multicenter test-negative case-control study in patients aged 16 visiting hospitals or clinics with signs or symptoms consistent with COVID-19 from July 1 to September 30, 2021, when the Delta variant was dominant (90% of severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] infections) nationwide in Japan. Vaccine effectiveness of BNT162b2 or mRNA-1273 against symptomatic SARS-CoV-2 infections was evaluated. Waning immunity among patients aged 16 to 64 was also assessed.
Results: We enrolled 1936 patients, including 396 test-positive cases and 1540 test-negative controls for SARS-CoV-2. The median age was 49 years, 53.4% were male, and 34.0% had underlying medical conditions. Full vaccination (receiving two doses 14 days before symptom onset) was received by 6.6% of cases and 38.8% of controls. Vaccine effectiveness of full vaccination against symptomatic SARS-CoV-2 infections was 88.7% (95% confidence interval [CI], 78.8-93.9) among patients aged 16 to 64 and 90.3% (95% CI, 73.6-96.4) among patients aged 65. Among patients aged 16 to 64, vaccine effectiveness within one to three months after full vaccination was 91.8% (95% CI, 80.3-96.6), and was 86.4% (95% CI, 56.9-95.7) within four to six months.
Conclusions: mRNA COVID-19 vaccines had high effectiveness against symptomatic SARS-CoV-2 infections in Japan during July 1 to September 30, 2021, when the Delta variant was dominant nationwide.
Keywords: COVID-19; Delta; Japan; SARS-CoV-2; vaccine effectiveness.
. 2022 Apr 19;ciac292.
doi: 10.1093/cid/ciac292. Online ahead of print.
Effectiveness of mRNA COVID-19 vaccines against symptomatic SARS-CoV-2 infections during the Delta variant epidemic in Japan: Vaccine Effectiveness Real-time Surveillance for SARS-CoV-2 (VERSUS)
Haruka Maeda[SUP] 1 2 [/SUP], Nobuo Saito[SUP] 3 [/SUP], Ataru Igarashi[SUP] 4 5 [/SUP], Masayuki Ishida[SUP] 6 [/SUP], Kazuya Suami[SUP] 7 [/SUP], Ai Yagiuchi[SUP] 7 [/SUP], Yuya Kimura[SUP] 8 [/SUP], Masaru Komino[SUP] 8 [/SUP], Hiromi Arai[SUP] 8 [/SUP], Toru Morikawa[SUP] 9 [/SUP], Iori Motohashi[SUP] 10 [/SUP], Rei Miyazawa[SUP] 10 [/SUP], Tetsu Moriyama[SUP] 11 [/SUP], Hiroshi Kamura[SUP] 12 [/SUP], Mayumi Terada[SUP] 13 [/SUP], Osamu Kuwamitsu[SUP] 14 [/SUP], Tomoichiro Hayakawa[SUP] 15 [/SUP], Eiichiro Sando[SUP] 16 17 [/SUP], Yasuji Ohara[SUP] 18 [/SUP], Osamu Teshigahara[SUP] 19 [/SUP], Motoi Suzuki[SUP] 20 [/SUP], Konosuke Morimoto[SUP] 1 [/SUP]
Affiliations
- PMID: 35438137
- DOI: 10.1093/cid/ciac292
Abstract
Background: Although high vaccine effectiveness of messenger RNA (mRNA) coronavirus disease 2019 (COVID-19) vaccines was reported in studies in several countries, data is limited from Asian countries, especially against the Delta (B.1.617.2) variant.
Methods: We conducted a multicenter test-negative case-control study in patients aged 16 visiting hospitals or clinics with signs or symptoms consistent with COVID-19 from July 1 to September 30, 2021, when the Delta variant was dominant (90% of severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] infections) nationwide in Japan. Vaccine effectiveness of BNT162b2 or mRNA-1273 against symptomatic SARS-CoV-2 infections was evaluated. Waning immunity among patients aged 16 to 64 was also assessed.
Results: We enrolled 1936 patients, including 396 test-positive cases and 1540 test-negative controls for SARS-CoV-2. The median age was 49 years, 53.4% were male, and 34.0% had underlying medical conditions. Full vaccination (receiving two doses 14 days before symptom onset) was received by 6.6% of cases and 38.8% of controls. Vaccine effectiveness of full vaccination against symptomatic SARS-CoV-2 infections was 88.7% (95% confidence interval [CI], 78.8-93.9) among patients aged 16 to 64 and 90.3% (95% CI, 73.6-96.4) among patients aged 65. Among patients aged 16 to 64, vaccine effectiveness within one to three months after full vaccination was 91.8% (95% CI, 80.3-96.6), and was 86.4% (95% CI, 56.9-95.7) within four to six months.
Conclusions: mRNA COVID-19 vaccines had high effectiveness against symptomatic SARS-CoV-2 infections in Japan during July 1 to September 30, 2021, when the Delta variant was dominant nationwide.
Keywords: COVID-19; Delta; Japan; SARS-CoV-2; vaccine effectiveness.