tetano
Editor, Senior Moderator
Front Immunol
. 2024 May 31:15:1359380.
doi: 10.3389/fimmu.2024.1359380. eCollection 2024. The effectiveness of booster vaccination of inactivated COVID-19 vaccines against susceptibility, infectiousness, and transmission of omicron BA.2 variant: a retrospective cohort study in Shenzhen, China
Yuxue Liao[SUP] #[/SUP][SUP] 1 [/SUP], Jiao Su[SUP] #[/SUP][SUP] 2 [/SUP], Jieru Zhao[SUP] #[/SUP][SUP] 3 [/SUP], Zhen Qin[SUP] 4 [/SUP], Zhuo'Ao Zhang[SUP] 4 [/SUP], Wei Gao[SUP] 1 [/SUP], Jia Wan[SUP] 1 [/SUP], Yi Liao[SUP] 1 [/SUP], Xuan Zou[SUP] 1 [/SUP], Xiaofeng He[SUP] 5 [/SUP]
Affiliations
Little studies evaluated the effectiveness of booster vaccination of inactivated COVID-19 vaccines against being infected (susceptibility), infecting others (infectiousness), and spreading the disease from one to another (transmission). Therefore, we conducted a retrospective cohort study to evaluate the effectiveness of booster vaccination of inactivated COVID-19 vaccines against susceptibility, infectiousness, and transmission in Shenzhen during an Omicron BA.2 outbreak period from 1 February to 21 April 2022. The eligible individuals were classified as four sub-cohorts according to the inactivated COVID-19 vaccination status of both the close contacts and their index cases: group 2-2, fully vaccinated close contacts seeded by fully vaccinated index cases (reference group); group 2-3, booster-vaccinated close contacts seeded by fully vaccinated index cases; group 3-2, fully vaccinated close contacts seeded by booster-vaccinated index cases; and group 3-3, booster-vaccinated close contacts seeded by booster-vaccinated index cases. Univariate and multivariate logistic regression analyses were applied to estimate the effectiveness of booster vaccination. The sample sizes of groups 2-2, 2-3, 3-2, and 3-3 were 846, 1,115, 1,210, and 2,417, respectively. We found that booster vaccination had an effectiveness against infectiousness of 44.9% (95% CI: 19.7%, 62.2%) for the adults ≥ 18 years, 62.2% (95% CI: 32.0%, 78.9%) for the female close contacts, and 60.8% (95% CI: 38.5%, 75.1%) for the non-household close contacts. Moreover, booster vaccination had an effectiveness against transmission of 29.0% (95% CI: 3.2%, 47.9%) for the adults ≥ 18 years, 38.9% (95% CI: 3.3%, 61.3%) for the female close contacts, and 45.8% (95% CI: 22.1%, 62.3%) for the non-household close contacts. However, booster vaccination against susceptibility did not provide any protective effect. In summary, this study confirm that booster vaccination of the inactivated COVID-19 vaccines provides low level of protection and moderate level of protection against Omicron BA.2 transmission and infectiousness, respectively. However, booster vaccination does not provide any protection against Omicron BA.2 susceptibility.
Keywords: BA.2 subvariant; COVID-19; infectiousness; susceptibility; transmission; vaccine effectiveness.
. 2024 May 31:15:1359380.
doi: 10.3389/fimmu.2024.1359380. eCollection 2024. The effectiveness of booster vaccination of inactivated COVID-19 vaccines against susceptibility, infectiousness, and transmission of omicron BA.2 variant: a retrospective cohort study in Shenzhen, China
Yuxue Liao[SUP] #[/SUP][SUP] 1 [/SUP], Jiao Su[SUP] #[/SUP][SUP] 2 [/SUP], Jieru Zhao[SUP] #[/SUP][SUP] 3 [/SUP], Zhen Qin[SUP] 4 [/SUP], Zhuo'Ao Zhang[SUP] 4 [/SUP], Wei Gao[SUP] 1 [/SUP], Jia Wan[SUP] 1 [/SUP], Yi Liao[SUP] 1 [/SUP], Xuan Zou[SUP] 1 [/SUP], Xiaofeng He[SUP] 5 [/SUP]
Affiliations
- PMID: 38881892
- PMCID: PMC11176464
- DOI: 10.3389/fimmu.2024.1359380
Little studies evaluated the effectiveness of booster vaccination of inactivated COVID-19 vaccines against being infected (susceptibility), infecting others (infectiousness), and spreading the disease from one to another (transmission). Therefore, we conducted a retrospective cohort study to evaluate the effectiveness of booster vaccination of inactivated COVID-19 vaccines against susceptibility, infectiousness, and transmission in Shenzhen during an Omicron BA.2 outbreak period from 1 February to 21 April 2022. The eligible individuals were classified as four sub-cohorts according to the inactivated COVID-19 vaccination status of both the close contacts and their index cases: group 2-2, fully vaccinated close contacts seeded by fully vaccinated index cases (reference group); group 2-3, booster-vaccinated close contacts seeded by fully vaccinated index cases; group 3-2, fully vaccinated close contacts seeded by booster-vaccinated index cases; and group 3-3, booster-vaccinated close contacts seeded by booster-vaccinated index cases. Univariate and multivariate logistic regression analyses were applied to estimate the effectiveness of booster vaccination. The sample sizes of groups 2-2, 2-3, 3-2, and 3-3 were 846, 1,115, 1,210, and 2,417, respectively. We found that booster vaccination had an effectiveness against infectiousness of 44.9% (95% CI: 19.7%, 62.2%) for the adults ≥ 18 years, 62.2% (95% CI: 32.0%, 78.9%) for the female close contacts, and 60.8% (95% CI: 38.5%, 75.1%) for the non-household close contacts. Moreover, booster vaccination had an effectiveness against transmission of 29.0% (95% CI: 3.2%, 47.9%) for the adults ≥ 18 years, 38.9% (95% CI: 3.3%, 61.3%) for the female close contacts, and 45.8% (95% CI: 22.1%, 62.3%) for the non-household close contacts. However, booster vaccination against susceptibility did not provide any protective effect. In summary, this study confirm that booster vaccination of the inactivated COVID-19 vaccines provides low level of protection and moderate level of protection against Omicron BA.2 transmission and infectiousness, respectively. However, booster vaccination does not provide any protection against Omicron BA.2 susceptibility.
Keywords: BA.2 subvariant; COVID-19; infectiousness; susceptibility; transmission; vaccine effectiveness.