In January 2021, Hong Kong marked the grim anniversary of the first reported case of coronavirus disease 2019 (COVID-19) in the territory.1 At the time of writing, Hong Kong has recorded a total of over 10 000 cases and a death toll of nearly 200, against the backdrop of over 110 000 000 cases and 2 500 000 deaths worldwide.1 2 Non-pharmaceutical interventions are capable of containing the pandemic3 with isolation of cases and quarantine of contacts being the fundamental components. However, pre-symptomatic and asymptomatic transmission of COVID-19 can undermine the effectiveness of isolation and quarantine if these measures are not coupled with rapid contact tracing and testing.4

In a recent review paper, it was found that neither absence nor presence of signs or symptoms of COVID-19 could accurately rule in or rule out the disease but anosmia or ageusia may be regarded as a red flag, and fever or cough is a sensitive indicator for identifying patients who need testing.5 In this issue of the Hong Kong Medical Journal, Leung et al6 report the findings of a cross-sectional study conducted using data collected from the first public temporary test centre in Hong Kong at the AsiaWorld-Expo. The authors found that although symptoms such as cough, sore throat, and runny nose were reported in 86.0% of persons who tested positive for COVID-19, these symptoms were non-specific and were also reported in 96.3% of persons who tested negative. The authors recommend that gatekeeping healthcare providers stay vigilant in arranging early testing and remain aware of both clinical and epidemiological manifestations of COVID-19. Another study conducted in Australia compared the efficiency and sensitivity of different testing approaches in detecting community transmission chains. The authors found that testing of all patients with respiratory symptoms in the community, in combination with thorough contact tracing, was most effective.7

Primary care doctors are the gatekeepers of our healthcare system, and the COVID-19 pandemic has highlighted the important role of primary care from the perspectives of infectious disease control and surveillance in the community. In many countries, primary care doctors are an integral part of surveillance systems for infectious diseases such as influenza.8 Similarly, well-trained primary care doctors are indispensable in the early identification and isolation of COVID-19 cases, by contributing to a successful surveillance system which can also identify changes in transmission patterns and at-risk population subgroups,9 as well as evaluate the efficacy of public health control measures.10

The cost-effectiveness of different COVID-19 testing strategies depends on the transmission scenario in the community, in addition to the cost per test.11 Reimer et al12 recommend evidence-based prioritisation of testing, where testing capacity and resources are limited, in order to flatten epidemic curves, lower values of effective reproduction number, and ease the burden on hospitals and intensive care units. Primary care doctors, being the first access point of the healthcare system for most of the general public, are in a prime position to practice evidence-based testing of patients in the community based on clinical assessments.

Primary care doctors are vital to the unprecedented global vaccination campaign. Healthcare workers are at a higher risk of contracting COVID-19, and in a systematic review, Bandyopadhyay et al13 found that general practitioners were one of the specialties at the highest risk of death from COVID-19. Healthcare workers, including primary care doctors, are recommended as a priority group for COVID-19 vaccination worldwide, including in Hong Kong14 where the COVID-19 Vaccination Programme was launched in late February.

Primary care doctors are also at the forefront of communicating with the community. Wong et al15 found that COVID-19 vaccine acceptance in the Hong Kong community is not high (37.2%; 95% confidence interval=34.5%-39.9%) and perceived severity, benefits of the vaccine, cues to action, access barriers, and harms were among the factors associated with acceptance. Studies from the H1N1 pandemic found that primary care doctors were highly influential in H1N1 vaccine uptake16 and it is reasonable to expect that this will also be the case for COVID-19 vaccines. Primary care doctors will require regular updates and accurate information on the vaccines to communicate clearly with their patients and public health authorities.17

A shortage of primary care professionals is associated with a higher death rate due to COVID-19.18 Primary health care has a crucial role in infectious disease epidemic management and well-integrated primary care and public health systems are vital for a cohesive response.19

All authors contributed to the editorial, approved the final version for publication, and take responsibility for its accuracy and integrity.

All authors have disclosed no conflicts of interest.

1. Centre for Health Protection, Hong Kong SAR Government. Latest situation of cases of COVID-19. Available from: https://www.chp.gov.hk/files/pdf/local_situation_covid19_en.pdf. Accessed 1 Mar 2021.

2. World Health Organization. WHO coronavirus (COVID-19) dashboard. Available from: https://covid19.who.int/?gclid=CjwKCAiAm-2BBhANEiwAe7eyFCS8TBp9v0BBj5Rl ysLobOmxwRL_p6NvscnuHkCOwNIaSIxv4DQRcRoCl8UQAvD_BwE. Accessed 1 Mar 2021.

3. Bo Y, Guo C, Lin C, et al. Effectiveness of non-pharmaceutical interventions on COVID-19 transmission in 190 countries from 23 January to 13 April 2020. Int J Infect Dis 2021;102:247-53. Crossref

4. Moghadas SM, Fitzpatrick MC, Sah P, et al. The implications of silent transmission for the control of COVID-19 outbreaks. Proc Natl Acad Sci U S A 2020;117:17513-5. Crossref

5. Struyf T, Deeks JJ, Dinnes J, et al. Signs and symptoms to determine if a patient presenting in primary care or hospital outpatient settings has COVID-19 disease. Cochrane Database Syst Rev 2020;7(7):CD013665. Crossref

6. Leung WL, Yu EL, Wong SC, et al. Findings from the first public COVID-19 temporary test centre in Hong Kong. Hong Kong Med J 2021;27:99-105. Crossref

7. Lokuge, K, Banks E, Davis S, et al. Exit strategies: optimising feasible surveillance for detection, elimination and ongoing prevention of COVID-19 community transmission. BMC Med 2021;19:50. Crossref

8. European Centre for Disease Prevention and Control. Facts about influenza surveillance. Available from: https:// www.ecdc.europa.eu/en/seasonal-influenza/surveillance-and-disease-data/facts-sentinel-surveillance. Accessed 1 Mar 2021.

9. Paquette D, Bell C, Roy M, et al. Laboratory-confirmed COVID-19 in children and youth in Canada, January 15-April 27, 2020. Can Commun Dis Rep 2020;46:121-4. Crossref

10. Lai S, Ruktanonchai NW, Zhou L, et al. Effect of non-pharmaceutical interventions to contain COVID-19 in China. Nature 2020;585:410-3. Crossref

11. Du Z, Pandey A, Bai Y, et al. Comparative cost-effectiveness of SARS-CoV-2 testing strategies in the USA: a modelling study. Lancet Public Health 2021;6:e184-91. Crossref

12. Reimer JR, Ahmed SM, Brintz B, et al. Using a clinical prediction rule to prioritize diagnostic testing leads to reduced transmission and hospital burden: A modeling example of early SARS-CoV-2. Clin Infect Dis 2021 Feb 23. Epub ahead of print. Crossref

13. Bandyopadhyay S, Baticulon RE, Kadhum M, et al. Infection and mortality of healthcare workers worldwide from COVID-19: a systematic review. BMJ Glob Health 2020;5:e003097.

14. Centre for Health Protection, Hong Kong SAR Government. Consensus interim recommendations on the use of COVID-19 vaccines in Hong Kong (as of Jan 7, 2021). Available from: https://www.chp.gov.hk/files/pdf/consensus_interim_recommendations_on_the_use_of_covid19_vaccines_inhk.pdf. Accessed 1 Mar 2021.

15. Wong MC, Wong EL, Huang J, et al. Acceptance of the COVID-19 vaccine based on the health belief model: A population-based survey in Hong Kong. Vaccine 2021;39:1148-56. Crossref

16. Danchin M, Biezen R, Manski-Nankervis JA, Kaufman J, Leask J. Preparing the public for COVID-19 vaccines: How can general practitioners build vaccine confidence and optimise uptake for themselves and their patients? Aust J Gen Pract 2020;49:625-9. Crossref

17. Kunin M, Engelhard D, Thomas S, Ashworth M, Piterman L. General practitioners’ challenges during the 2009/A/H1N1 vaccination campaigns in Australia, Israel and England: a qualitative study. Aust Fam Physician 2013;42:811-5.

18. Baltrus PT, Douglas M, Li C, et al. Percentage of Black population and primary care shortage areas associated with higher COVID-19 case and death rates in Georgia counties. South Med J 2021;114:57-62. Crossref

19. Desborough J, Dykgraaf SH, Phillips C, et al. Lessons for the global primary care response to COVID-19: a rapid review of evidence from past epidemics. Fam Pract 2021 Feb 15. Epub ahead of print.