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COVID-19 patients with negative results on initial screening: Experience of Brunei Darussalam
Vui Heng Chong1,2,3, Justin Wong4, Muhammad Syafiq Abdullah1,3
1Department of Medicine, Raja Isteri Pengiran Anak Saleha Hospital, Bandar Seri Begawan, Brunei Darussalam.
Insights
Some coronavirus disease 2019 (COVID-19) cases initially test negative but later become positive upon re-testing. This highlights the importance of continued monitoring and testing during infectious disease outbreaks.
Area of Science:
- Infectious Diseases
- Epidemiology
- Public Health
Background:
- Early diagnosis, isolation, and quarantine are crucial for controlling infectious disease outbreaks.
- Brunei Darussalam implemented quarantine measures for suspected coronavirus disease 2019 (COVID-19) cases, including testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
Purpose of the Study:
- To report on cases of COVID-19 that initially tested negative but later tested positive after symptom development.
- To analyze the proportion of initially false-negative COVID-19 cases within the overall case count in Brunei Darussalam.
Main Methods:
- Retrospective analysis of 10 COVID-19 cases initially testing negative.
- Review of quarantine and testing protocols in Brunei Darussalam during the study period.
Main Results:
- Ten cases (3.8% of 266 total) initially tested negative for COVID-19 but were positive on re-testing after symptom onset.
- All 10 cases were under home quarantine and tested early in their quarantine period.
Conclusions:
- Initial negative test results for COVID-19 do not rule out infection, especially in symptomatic individuals.
- The findings suggest a need for re-testing or extended monitoring for suspected cases, particularly those initially tested early in their quarantine period.
- Changes in quarantine policy (e.g., designated centres, later testing) may impact detection rates.
Abstract:
In any infectious disease outbreak, early diagnosis, isolation of cases and quarantine of contacts are central to disease containment. In Brunei Darussalam, suspected cases of coronavirus disease 2019 (COVID-19) were quarantined either at home or at designated centres and were tested immediately for severe acute respiratory syndrome coronavirus 2. We report on 10 cases of COVID-19 that initially tested negative for COVID-19 and were positive on re-testing after becoming symptomatic. These cases comprised 3.8% of the 266 total confirmed COVID-19 cases in Brunei Darussalam as of 9 July 2021, when this study was conducted. All the cases were in quarantine at home and were tested early during their quarantine period. Since then, home quarantine has been replaced by quarantine at designated centres only, with testing on the 12th day of quarantine.
