Scientific Committee on Emerging and Zoonotic Disease and Scientific Committee on Vaccine Preventable Diseases Consensus Interim Recommendations on the Use of COVID-19 Vaccines in Hong Kong (As of Jan 7, 2021) Introduction The ongoing COVID-19 pandemic causes a significant disease burden worldwide. In Hong Kong, cases and outbreaks continue to be reported. To reduce the impacts of COVID-19 on health and society, vaccines against COVID-19 is considered an important public health tool for containing the pandemic in the medium and long term. On 7 January 2021, the Scientific Committee on Emerging and Zoonotic Diseases (SCEZD), the Scientific Committee on Vaccine Preventable Diseases (SCVPD), and the Expert Advisory Panel to Chief Executive (EAP) reviewed the latest scientific evidence on the epidemiology and clinical features of COVID-19, published data on the COVID- 19 vaccines be procured by the Hong Kong SAR Government, local data as well as overseas recommendations/practices, and provides recommendations on the population groups and circumstances for the use of COVID-19 vaccines in Hong Kong. COVID-19 Vaccines 2. At the meeting held on 13 August 2020, the joint SCEZD and SCVPD together with the EAP reviewed the then scientific development of COVID 19 vaccines and prioritization of target groups for COVID 19 vaccines in Hong Kong. The meeting recommended that vaccine procurement would be aimed at the whole Hong Kong population in the long run. In anticipation of a limited supply at the early stage when vaccines are available, a phased approach has to be taken with certain priority groups of the local population identified to be vaccinated first, in order to reduce morbidity and mortality and maintain essential services. Priority should be accorded to high-risk groups which are most vulnerable to the development of severe disease or death from COVID-19 infection and greater risks of exposure to the COVID-19 virus and/or transmitting the virus to susceptible and vulnerable individuals. Priority has been suggested to be accorded to healthcare workers, residents of residential care homes, Government frontline staff involved in health-related work, persons aged 60 years or above, and persons with chronic medical problems. The meeting recommended that the 1 priority groups to be vaccinated at a certain stage to be further worked out when information about the vaccine supply, data on the vaccines’ safety profile and efficacy on various population subgroups becomes available. 3. On 11 December 2020, the Hong Kong SAR Government announced the latest development of COVID-19 vaccine procurement1. The Government is entering into agreement with vaccine developers of three vaccine candidates, namely Fosun Pharma/BioNTech for BNT162b2, Sinovac Biotech (Hong Kong) for CoronaVac and AstraZeneca for AZD1222. Characteristics of these three candidates are highlightedn i Table 1. The Government is developing a territory-wide COVID-19 vaccination programme, with potential delivery strategies including vaccination centres, outreach sites, etc. Table 1 - Characteristics of the three COVID-19 vaccines Vaccine BNT162b2 CoronaVac AZD1222 Adenovirus vector Platform mRNA Inactivated (non-replicating) Dosing schedule (interval between 1st 2 dose 2 dose 2 dose and 2nd dose) (at least 21 days) (14 or 28 days) (4 to 12 weeks) Packaging Multi-vial (5) NA Multi-vial Y Dilution required NA NA (sodium chloride) 6 months at -75°C 2-8°C (to be Shelf life (±15°C); 6 months at 2-8°C confirmed) 5 days at 2-8°C Route of IM IM IM administration 2 Emergency Use Approval for COVID-19 vaccines in Hong Kong 4. To facilitate timely access to COVID-19 vaccines without compromising proper regulatory decision-making, the WHO encourages countries’ regulatory authorities to develop and implement regulatory pathways to use a risk-based approach to assess the quality, safety and efficacy of vaccines. Emergency approval, and/or expedited fast-track regulatory pathways should be in place as part of pandemic preparedness2. In Hong Kong, given the nature of the threat from COVID-19, the Government has put in place a legislative framework (Cap 599K) to enable the public to gain early access to promising vaccines when those products have not yet received full registration approval. An Advisory Panel on COVID-19 Vaccines (AP), comprising experts from relevant fields and sectors, has been set up to advise the Secretary for Food and Health on the authorization of COVID-19 vaccines for emergency use based on the available data concerning safety, efficacy, quality and scientific evidence, and on matters related to administration of the vaccine(s). Healthcare providers should refer to details regarding use of the individual product advised by the AP. Recommendation 5. The joint SCZED, SCVPD and EAP convened on 7 January 2021, in advance of the completion of the AP’s review of the Emergency Use Approval applications, to provide interim recommendations to the Government on allocation of initial doses, and on COVID-19 vaccines for use in Hong Kong, subject to the approval of emergency use by the Government. The interim recommendations might be updated based on additional safety and efficacy data from phase III clinical trials, international developments and conditions of the Emergency Use Approval. 6. The current recommendation focused on BNT162b2 and AZD1222, which is expected to be available in Hong Kong in the first and third quarter of 2021, based on the latest available data and information as of 7 January 2021. Recommendation on CoronaVac, which is expected to be delivered to Hong Kong in January 2021, will be updated should more clinical information become available. 3 Prioritization 7. While the COVID-19 vaccination aims to cover the whole Hong Kong population in the long run, COVID-19 vaccines available in early 2021 will be insufficient to cover the entire population. It would also be infeasible to vaccinate the whole population over a short time period. It is important to identify the highest priority groups to be vaccinated in the first phase, before moving to subsequent phases when vaccines will be offered to an increasingly larger part of the population. The optimal prioritization depends on the objective of the vaccination strategy, as well as the characteristics of the vaccine, in particular its efficacy against infection and onward transmission. The best use of available vaccine will also be dependent on the epidemiological scenario, in terms of the degree of COVID-19 ongoing transmission and burden in the local community. 8. In order to interrupt community transmission, vaccinating a sufficiently large proportion of the population with a vaccine highly effective at preventing infection and transmission is needed. The available evidence from phase III clinical studies of BNT162b2 and AZD1222 showed that the vaccines are efficacious in preventing symptomatic COVID-19 diseases. There is limited efficacy data on their effect in preventing asymptomatic SARS-CoV-2 infection, and a lack of data on reducing transmission. At the start of the vaccination programme, there is unlikely sufficient evidence on the effects of vaccination on transmission. In addition, vaccine availability will be limited and a sufficiently high level of vaccine coverage to interrupt community transmission would be difficult to achieve in the initial phase of the vaccination programme. 9. Hong Kong is currently experiencing community transmission of SARS- CoV-2. Taking into account the nature and supply of vaccines available at this stage, and the local epidemiology and disease burden, it justifies an initial focus on direct reduction of mortality and severe morbidity for the most at-risk; and protection of health and social care system. 10. Current scientific evidence strongly indicates that increasing age is the single greatest risk of mortality from COVID-19, and the risk increases exponentially with age. This trend was also reflected in our local data (persons aged 60 or above represented up to 95% of local mortality with crude case 4 fatality ratio: 30-59: 0.2%; 60-69: 1.4%; 70-79: 7.4%; 80+: 26.0%) 1 . In particular, those living in residential care homes (RCH) for older adults are disproportionately affected by COVID-19. They are in general at higher clinical risk of severe disease and mortality. In addition, the closed congregate settings facilitate transmission of infection, and increase the risk of major outbreaks According to the local data2, for persons aged 60 years or above, those who are residents at RCHE/RCHDs were found to be at higher risk of severe outcomes and death compared to community-dwelling elders, with a two-times higher odds of severe COVID-19. The case-fatality ratio for cases involving residential care homes for the elderly (RCHE)/ residential care homes for persons with disabilities (RCHD) residents was about 18%. In larger outbreaks at RCHE/RCHD settings, the attack rate among residents ranged from 20% to 92%. It is considered that older adults residing in care homes should be the highest priority for vaccination. Staff of RCHE/RCHD should be vaccinated alongside. In addition, other institutionalized facilities with closed settings are also at increased risk of outbreaks; and the residents and staff should also be considered as a priority group, even though they may not be at same level of risk as institionalized elders. 11. Frontline health and social care workers are at increased risk of exposure to infection with COVID-19; and of transmitting that infection to susceptible and vulnerable patients in health and social care settings. Vaccination of healthcare workers protects the health and social care service, and improves the resilience of the healthcare system. Protecting the health and social care workers from infection would also reduce the risks of having vulnerable patients / elders exposed to infected care workers. 12. Apart from frontline health and social care workers, some other occupational groups which are at increased risk of exposure to COVID-19 (e.g.