Background: Counseling support for HIV self-testing (HIVST) users is essential to ensure support and linkage to care among men who have sex with men (MSM). An HIVST service with web-based real-time instruction, pretest, and posttest counseling provided by trained administrators (HIVST-OIC) was developed by previous projects. Although the HIVST-OIC was highly effective in increasing HIVST uptake and the proportion of HIVST users receiving counseling along with testing, it required intensive resources to implement and sustain. The service capacity of HIVST-OIC cannot meet the increasing demands of HIVST. Objective: This randomized controlled trial primarily aims to establish whether HIVST-chatbot, an innovative HIVST service with web-based real-time instruction and counseling provided by a fully automated chatbot, would produce effects that are similar to HIVST-OIC in increasing HIVST uptake and the proportion of HIVST users receiving counseling alongside testing among MSM within a 6-month follow-up period. Methods: A parallel-group, noninferiority randomized controlled trial will be conducted with Chinese-speaking MSM aged ≥18 years with access to live-chat applications. A total of 528 participants will be recruited through multiple sources, including outreach in gay venues, web-based advertisement, and peer referral. After completing the baseline telephone survey, participants will be randomized evenly into the intervention or control groups. Intervention group participants will watch a web-based video promoting HIVST-chatbot and receive a free HIVST kit. The chatbot will contact the participant to implement HIVST and provide standard-of-care, real-time pretest and posttest counseling and instructions on how to use the HIVST kit through WhatsApp. Control group participants will watch a web-based video promoting HIVST-OIC and receive a free HIVST kit in the same manner. Upon appointment, a trained testing administrator will implement HIVST and provide standard-of-care, real-time pretest and posttest counseling and instructions on how to use the HIVST kit through live-chat applications. All participants will complete a telephone follow-up survey 6 months after the baseline. The primary outcomes are HIVST uptake and the proportion of HIVST users receiving counseling support along with testing in the past 6 months, measured at month 6. Secondary outcomes include sexual risk behaviors and uptake of HIV testing other than HIVST during the follow-up period. Intention-to-treat analysis will be used. Results: Recruitment and enrollment of participants started in April 2023. Conclusions: This study will generate important research and policy implications regarding chatbot use in HIVST services. If HIVST-chatbot is proven noninferior to HIVST-OIC, it can be easily integrated into existing HIVST services in Hong Kong, given its relatively low resource requirements for implementation and maintenance. HIVST-chatbot can potentially overcome the barriers to using HIVST. Therefore, the coverage of HIV testing, the level of support, and the linkage to care for MSM HIVST users will be increased. Trial Registration: ClinicalTrial.gov NCT05796622; https://clinicaltrials.gov/ct2/show/NCT05796622 International Registered Report Identifier (IRRID): PRR1-10.2196/48447

A COVID-19 vaccine booster dose is effective and safe for older adults. This study investigated facilitators and barriers to take up a COVID-19 vaccine booster dose among older adults in Hong Kong. Participants were Chinese-speaking community-dwelling adults aged ≥65 years. Telephone numbers were randomly selected from up-to-date telephone directories. A total of 395 participants completed the telephone interview. Logistic regression models were fitted. Among the participants, 31.6% received a COVID-19 vaccine booster dose. After adjustment for significant background characteristics, positive attitudes toward the booster dose, perceiving significant others would support them to receive the booster dose, and less uncertainty regarding the choice of the booster dose was associated with higher uptake of a COVID-19 vaccine booster dose. Concerns about poorer responses to the booster dose due to older age and the presence of chronic conditions were negatively associated with the dependent variable. In addition, the belief that governmental promotional materials could address their concern and were helpful for them to make decisions was associated with a higher COVID-19 vaccine booster dose uptake. Improving booster dose health promotion materials, modifying perceptions, involving significant others and reducing uncertainty are potentially useful strategies to improve COVID-19 vaccine booster dose uptake among older adults.

During the Coronavirus Disease 2019 (COVID-19) pandemic, seasonal influenza remained a significant health threat for older adults. Seasonal influenza vaccination (SIV) is highly effective and safe for older adults. This study investigated the associations of COVID-19 vaccination, perceptions related to COVID-19 and SIV, with the behavioural intention to receive SIV among older adults in Hong Kong, China. A random telephone survey was conducted among 440 community-dwelling Hong Kong residents aged 65 years or above, between November 2021 and January 2022. Among the participants, 55.7% intended to receive SIV in the next year. After adjustment for significant background characteristics, concern about whether SIV and COVID-19 vaccination would negatively affect each other was associated with a lower intention to receive SIV, while a perceived higher risk of co-infection with COVID-19 and seasonal influenza was positively associated with the dependent variable. In addition, the perceived severe consequences of seasonal influenza, perceived benefits of SIV, received cues to action from doctors and participants’ family members or friends, and the perception that more older people would receive SIV was associated with a higher behavioural intention. Future programmes promoting SIV among older adults should modify perceptions related to COVID-19 vaccination and SIV at the same time.

COVID-19 vaccination is proven to be effective and safe for older adults. This study investigated the impacts of incentives and health promotional materials provided by the government on the completion of the primary COVID-19 vaccination series among older adults in Hong Kong. Participants were Chinese-speaking community-dwelling adults aged ≥65 years. Telephone numbers were randomly selected from up-to-date Hong Kong telephone directories. A total of 440 participants completed the telephone interview. Logistic regression models were fitted. Among the participants, 58.4% had completed the primary COVID-19 vaccination series. Most participants believed that incentives provided by the government had almost no impact on increasing their motivation to receive COVID-19 vaccination, and less than half thought that vaccination promotional materials produced by the government could address their concerns and help them make decisions. After adjustment for significant background characteristics, we found perceived higher impacts of the incentives and belief that vaccination promotional materials produced by the government could address their concern and were helpful for them to make decisions to be associated with a higher rate of completion of primary COVID-19 vaccination series. Perceptions supporting COVID-19 vaccination and less decisional conflict regarding the choice of vaccine were also positively associated with the dependent variable. Government should develop incentives and health promotional materials tailored to the needs of older adults.

A second COVID-19 vaccine booster dose is effective and safe for older adults. This study investigated hesitancy to take up a second COVID-19 vaccine booster dose and its determinants among older adults in Hong Kong. Participants were Chinese-speaking community-dwelling adults aged 65 years or above. Telephone numbers were randomly selected from up-to-date telephone directories. A total of 370 participants completed the telephone survey. Logistic regression models were fitted for data analysis. Among the participants, half (52.4%) were hesitant to receive the second COVID-19 vaccine booster dose. After adjustment for significant background characteristics, perceived benefits (AOR: 0.50, 95%CI: 0.42, 0.60), cues to action (AOR: 0.39, 95%CI: 0.30, 0.52), and perceived self-efficacy (AOR: 0.37, 95%CI: 0.21, 0.66) of receiving the second booster dose were associated with lower vaccine hesitancy. Perceived barriers (AOR: 1.23, 95%CI: 1.12, 1.34) and vaccine fatigue (tired of receiving repeated COVID-19 vaccination) (AOR: 1.90, 95%CI: 1.52, 2.38) were associated with higher vaccine hesitancy. Level of hesitancy to receive the second booster dose was high among older adults in Hong Kong. Health authorities should address vaccine fatigue and modify perceptions related to the second booster dose.