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. 2022 Jul 30;40(32):4654-4662.
doi: 10.1016/j.vaccine.2022.06.007. Epub 2022 Jun 8.

Corowa-kun: A messenger app chatbot delivers COVID-19 vaccine information, Japan 2021

Takaaki Kobayashi  1 , Yuka Nishina  2 , Hana Tomoi  3 , Ko Harada  4 , Kyuto Tanaka  5 , Eiyu Matsumoto  6 , Kenta Horimukai  7 , Jun Ishihara  8 , Shugo Sasaki  9 , Kanako Inaba  10 , Kyosuke Seguchi  11 , Hiromizu Takahashi  2 , Jorge L Salinas  6 , Yuji Yamada  12
Affiliations

Corowa-kun: A messenger app chatbot delivers COVID-19 vaccine information, Japan 2021

Takaaki Kobayashi et al. Vaccine. .

Abstract

Background: There is a long history in Japan of public concerns about vaccine adverse events. Few studies have assessed how mobile messenger apps affect COVID-19 vaccine hesitancy.

Methods: Corowa-kun, a free chatbot, was created on February 6, 2021 in LINE, the most popular messenger app in Japan. Corowa-kun provides instant, automated answers to 70 frequently asked COVID-19 vaccine questions. A cross-sectional survey with 21 questions was performed within Corowa-kun during April 5-12, 2021.

Results: A total of 59,676 persons used Corowa-kun during February-April 2021. Of them, 10,192 users (17%) participated in the survey. Median age was 55 years (range 16-97), and most were female (74%). COVID-19 vaccine hesitancy reported by survey respondents decreased from 41% to 20% after using Corowa-kun. Of the 20% who remained hesitant, 16% (1,675) were unsure, and 4% (364) did not intend to be vaccinated. Factors associated with vaccine hesitancy were: age 16-34 (odds ratio [OR] = 3.7; 95% confidential interval [CI]: 3.0-4.6, compared to age ≥ 65), female sex (OR = 2.4; Cl: 2.1-2.8), and history of a previous vaccine side-effect (OR = 2.5; Cl: 2.2-2.9). Being a physician (OR = 0.2; Cl: 0.1-0.4) and having received a flu vaccine the prior season (OR = 0.4; Cl: 0.3-0.4) were protective.

Conclusions: A substantial number of people used the chabot in a short period. Mobile messenger apps could be leveraged to provide accurate vaccine information and to investigate vaccine intention and risk factors for vaccine hesitancy.

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Conflict of interest statement

Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

Fig. 1
Fig. 1
Corowa-kun’s Consultation Room: a free messenger app chatbot, Japan 2021 Corowa-kun is the mascot of an online chatbot. This chatbot in LINE is used to answer COVID-19 vaccine frequently asked questions (FAQs) via text messages. As of May 10th, 70 FAQs are available.
Fig. 2
Fig. 2
Reported COVID-19 vaccine acceptance during a Cross Sectional Survey using Corowa-kun, Japan, April 5th–12th 2021 (n = 10,192) *There was a statistically significant difference in vaccine hesitancy between before and after using Corowa-kun (p < 0.01, Chi-square test).
Fig. 3
Fig. 3
Reasons provided for COVID-19 hesitancy (A) and acceptance (B), COVID-19 vaccine survey, Japan, 2021.
See this image and copyright information in PMC

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