Performance of the World Health Organisation suspected COVID-19 case definition in cluster-associated and sporadic SARS-CoV-2 transmission in Malaysia.

INTRODUCTION: Cluster-associated transmission has contributed to the majority of COVID-19 cases in Malaysia. Although widely used, the performance of the World Health Organization (WHO) case definition for suspected COVID19 in environments with high numbers of such cases has not been reported. MATERIALS AND METHODS: All suspected cases of COVID-19 that self-presented to hospitals or were cluster screened from 1st April to 31st May 2020 were included. Positive SARS-CoV-2 rRT-PCR was used as the diagnostic reference for COVID-19. RESULTS: 540 individuals with suspected COVID-19 were recruited. Two-third of patients were identified through contact screening, while the rest presented sporadically. Overall COVID-19 positivity rate was 59.4% (321/540) which was higher in the cluster screened group (85.6% vs. 11.6%, p<0.001). Overall, cluster-screened COVID-19 cases were significantly younger, had fewer comorbidities and were less likely to be symptomatic than those present sporadically. Mortality was significantly lower in the cluster-screened COVID-19 cases (0.3% vs. 4.5%, p<0.05). A third of all chest radiographs in confirmed COVID-19 cases were abnormal, with consolidation, ground-glass opacities or both predominating in the peripheral lower zones. The WHO suspected case definition for COVID-19 accurately classified 35.4% of all COVID-19 patients, a rate not improved by the addition of baseline radiographic data. Misclassification rate was higher among the cluster-associated cases (80.6%) compared to sporadic cases (35.3%). CONCLUSION: COVID-19 cases in Malaysia identified by active tracing of community cluster outbreaks had lower mortality rate. The WHO suspected COVID-19 performed poorly in this setting even when chest radiographic information was available, a finding that has implications for future spikes of the disease in countries with similar transmission characteristics.

A pre-admission triaging tool to predict severe COVID-19 cases: ABCD score.

INTRODUCTION: Isolation of SARS-CoV-2-infected individuals is an important COVID-19 pandemic control measure. While most cases have uncomplicated infection, a small proportion of them has developed life-threatening disease. We set up a retrospective study to determine preadmission triaging tool to predict the development of severe COVID-19. MATERIALS AND METHODS: A retrospective study was conducted from 1 October 2020 to 31 January 2021 with enrolment of all SARS-CoV-2 PCR-confirmed persons aged ≥13 years. The disease severity was assessed on admission and daily throughout the hospitalisation. Test-positive individuals were considered as having "severe COVID-19" if they had ≥1 of the following: room air oxygen saturation 30 breaths/minute, signs of severe respiratory distress, or received mechanical ventilation and/or vasopressor therapy. Uni- and multi-variate analyses using SPSS Statistics Ver. 26 were performed. RESULTS: We showed that age ≥ 60 years, BMI ≥ 30.0, presentation on days 7-12 of illness, and ≥1 comorbidity were associated with development of severe COVID-19. A scoring system based on the four variables is a useful COVID-19 risk assessment tool. A total score ≥2 had a sensitivity of 60.9%, specificity of 88.2%, positive predictive value of 37.8% and negative predictive value of 95.0%. CONCLUSION: Development of preadmission triaging tool can help health care providers (HCPs) decide on the placement of test-positive individuals to appropriate isolation facilities according to the risk of developing severe COVID-19.