tetano
Editor, Senior Moderator
Influenza Other Respir Viruses
. 2023 Feb 1;17(2):e13094.
doi: 10.1111/irv.13094. eCollection 2023 Feb.
National seroepidemiological study of COVID-19 after the initial rollout of vaccines: Before and at the peak of the Omicron-dominant period in Japan
Takeshi Arashiro[SUP] 1 2 [/SUP], Satoru Arai[SUP] 1 [/SUP], Ryo Kinoshita[SUP] 1 [/SUP], Kanako Otani[SUP] 1 [/SUP], Sho Miyamoto[SUP] 2 [/SUP], Daisuke Yoneoka[SUP] 1 [/SUP], Taro Kamigaki[SUP] 1 [/SUP], Hiromizu Takahashi[SUP] 3 [/SUP], Hiromi Hibino[SUP] 3 [/SUP], Mai Okuyama[SUP] 1 [/SUP], Ai Hayashi[SUP] 1 [/SUP], Fuka Kikuchi[SUP] 1 [/SUP], Saeko Morino[SUP] 1 [/SUP], Sayaka Takanashi[SUP] 1 [/SUP], Takaji Wakita[SUP] 4 [/SUP], Keiko Tanaka-Taya[SUP] 1 [/SUP], Tadaki Suzuki[SUP] 2 [/SUP], Motoi Suzuki[SUP] 1 [/SUP]
Affiliations
Abstract
Background: Based on routine surveillance data, Japan has been affected much less by COVID-19 compared with other countries. To validate this, we aimed to estimate SARS-CoV-2 seroprevalence and examine sociodemographic factors associated with cumulative infection in Japan.
Methods: A population-based serial cross-sectional seroepidemiological investigation was conducted in five prefectures in December 2021 (pre-Omicron) and February-March 2022 (Omicron [BA.1/BA.2]-peak). Anti-nucleocapsid and anti-spike antibodies were measured to detect infection-induced and vaccine/infection-induced antibodies, respectively. Logistic regression was used to identify associations between various factors and past infection.
Results: Among 16 296 participants (median age: 53 [43-64] years), overall prevalence of infection-induced antibodies was 2.2% (95% CI: 1.9-2.5%) in December 2021 and 3.5% (95% CI: 3.1-3.9%) in February-March 2022. Factors associated with past infection included those residing in urban prefectures (Tokyo: aOR 3.37 [95% CI: 2.31-4.91], Osaka: aOR 3.23 [95% CI: 2.17-4.80]), older age groups (60s: aOR 0.47 [95% CI 0.29-0.74], 70s: aOR 0.41 [95% CI 0.24-0.70]), being vaccinated (twice: aOR 0.41 [95% CI: 0.28-0.61], three times: aOR 0.21 [95% CI: 0.12-0.36]), individuals engaged in occupations such as long-term care workers (aOR: 3.13 [95% CI: 1.47-6.66]), childcare workers (aOR: 3.63 [95% CI: 1.60-8.24]), food service workers (aOR: 3.09 [95% CI: 1.50-6.35]), and history of household contact (aOR: 26.4 [95% CI: 20.0-34.8]) or non-household contact (aOR: 5.21 [95% CI:3.80-7.14]) in February-March 2022. Almost all vaccinated individuals (15 670/15 681) acquired binding antibodies with higher titers among booster dose recipients.
Conclusions: Before Omicron, the cumulative burden was >10 times lower in Japan (2.2%) compared with the US (33%), the UK (25%), or global estimates (45%), but most developed antibodies owing to vaccination.
Keywords: Japan; coronavirus disease 2019 (COVID‐19); humoral immunity; seroepidemiologic studies; severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2); vaccines.
. 2023 Feb 1;17(2):e13094.
doi: 10.1111/irv.13094. eCollection 2023 Feb.
National seroepidemiological study of COVID-19 after the initial rollout of vaccines: Before and at the peak of the Omicron-dominant period in Japan
Takeshi Arashiro[SUP] 1 2 [/SUP], Satoru Arai[SUP] 1 [/SUP], Ryo Kinoshita[SUP] 1 [/SUP], Kanako Otani[SUP] 1 [/SUP], Sho Miyamoto[SUP] 2 [/SUP], Daisuke Yoneoka[SUP] 1 [/SUP], Taro Kamigaki[SUP] 1 [/SUP], Hiromizu Takahashi[SUP] 3 [/SUP], Hiromi Hibino[SUP] 3 [/SUP], Mai Okuyama[SUP] 1 [/SUP], Ai Hayashi[SUP] 1 [/SUP], Fuka Kikuchi[SUP] 1 [/SUP], Saeko Morino[SUP] 1 [/SUP], Sayaka Takanashi[SUP] 1 [/SUP], Takaji Wakita[SUP] 4 [/SUP], Keiko Tanaka-Taya[SUP] 1 [/SUP], Tadaki Suzuki[SUP] 2 [/SUP], Motoi Suzuki[SUP] 1 [/SUP]
Affiliations
- PMID: 36824391
- PMCID: PMC9890143
- DOI: 10.1111/irv.13094
Abstract
Background: Based on routine surveillance data, Japan has been affected much less by COVID-19 compared with other countries. To validate this, we aimed to estimate SARS-CoV-2 seroprevalence and examine sociodemographic factors associated with cumulative infection in Japan.
Methods: A population-based serial cross-sectional seroepidemiological investigation was conducted in five prefectures in December 2021 (pre-Omicron) and February-March 2022 (Omicron [BA.1/BA.2]-peak). Anti-nucleocapsid and anti-spike antibodies were measured to detect infection-induced and vaccine/infection-induced antibodies, respectively. Logistic regression was used to identify associations between various factors and past infection.
Results: Among 16 296 participants (median age: 53 [43-64] years), overall prevalence of infection-induced antibodies was 2.2% (95% CI: 1.9-2.5%) in December 2021 and 3.5% (95% CI: 3.1-3.9%) in February-March 2022. Factors associated with past infection included those residing in urban prefectures (Tokyo: aOR 3.37 [95% CI: 2.31-4.91], Osaka: aOR 3.23 [95% CI: 2.17-4.80]), older age groups (60s: aOR 0.47 [95% CI 0.29-0.74], 70s: aOR 0.41 [95% CI 0.24-0.70]), being vaccinated (twice: aOR 0.41 [95% CI: 0.28-0.61], three times: aOR 0.21 [95% CI: 0.12-0.36]), individuals engaged in occupations such as long-term care workers (aOR: 3.13 [95% CI: 1.47-6.66]), childcare workers (aOR: 3.63 [95% CI: 1.60-8.24]), food service workers (aOR: 3.09 [95% CI: 1.50-6.35]), and history of household contact (aOR: 26.4 [95% CI: 20.0-34.8]) or non-household contact (aOR: 5.21 [95% CI:3.80-7.14]) in February-March 2022. Almost all vaccinated individuals (15 670/15 681) acquired binding antibodies with higher titers among booster dose recipients.
Conclusions: Before Omicron, the cumulative burden was >10 times lower in Japan (2.2%) compared with the US (33%), the UK (25%), or global estimates (45%), but most developed antibodies owing to vaccination.
Keywords: Japan; coronavirus disease 2019 (COVID‐19); humoral immunity; seroepidemiologic studies; severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2); vaccines.