The implementation of an active surveillance integrating information technology and drive-through coronavirus testing station for suspected COVID-19 cases.

To the editor,

We read with great interest the study by Chen et al., which showed high seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among 105 healthcare workers exposed to four laboratory confirmed coronavirus disease 2019 (COVID-19). This study indicated the possible nosocomial spread of COVID-19. As for August 29, 2020, SARS-CoV-2 causing has involved more than 24 million patients and COVID-19 has been associated with a case fatality rate of 3.4%. Although COVID-19 can present as asymptomatic or mild pneumonia, a significant portion of patients presenting with severe pneumonia or acute respiratory distress syndrome required hospitalization. Because severe cases can carry high viral load and SARS-CoV-2 owns a great ability to infect human, nosocomial transmission of COVID-19 is a serious concern. In addition to appropriate personal protective equipment (PPE), early detection and prompt isolation of patients with SARS-CoV-2 infection is essential to prevent COVID-19 nosocomial spread.

Recently, Lin et al. used information technology to build an inpatient COVID-19 alarm system in active surveillance of suspected COVID-19 cases among inpatients with nonresolving pneumonia after treatment. However, caregivers and HCWs – another population within the hospital at risk of acquiring SARS-CoV-2 infection from nosocomial transmission was missed in this study. By contrast, a cross-sectional study in Singapore reported that a multi-pronged approach including risk-based PPE, staff fever and sickness surveillance, and enhanced medical surveillance of unwell staff was effective in prevent HCW from SARS-CoV-2 infection. To effectively prevent inpatients, caregivers and HCWs from nosocomial spread of SARS-CoV-2 within hospital, we built a “quarantine map” to help clinicians to early detect suspected COVID-19 cases among them using information technology.

Chi Mei medical center is a 1284-bed tertiary care hospital which have 2 buildings and one campus. Three confirmed COVID-19 patients were hospitalized between March and May. Since 2020/02/21, the hospital implemented an active surveillance of suspected COVID-19 cases using information technology. First, all inpatients was screened using information technology system and aimed to identify the patients met the at least two of three criteria: 1) fever, defined as temperature≥ 38 °C; 2) cough, defined as use of antitussive agents; 3) pneumonia, denied as key words of pneumonia pattern in the chest x-ray report. When inpatients had more than 2 of 3 criteria meet, COVID-19 case manager would review the chart. If the patient did not receive PCR test for SARS-CoV-2, the case manager would send a message to the primary care team to remind them to perform the diagnostic test. Otherwise, the primary care team could consult rapid response team infection specialist (R.R.T) to evaluate the patient. All patients would be followed up daily until the patient had receiving test for SARS-CoV-2 or had been assessed by R.R.T. Although inpatients hospitalized in intensive care unit and pediatric patients were excluded because they often had an infection source when admission, the primary care team in these two unit could decide when to perform PCR test. In addition, the HCWs and caregivers should report the body temperature and the symptom of infection then integrate to the surveillance system daily. Once they have fever or infection symptom, they should stop working until the associated symptom resolved for at least 24 h. Any cluster of fever and respiratory symptoms screened among the three groups in the same or neighboring room cared by the same nursing staff within a station by quarantine map was sent for SARS-CoV-2 PCR test immediately (Fig. 1 ).

Fig. 1

Quarantine map.

To improve the process of collecting clinical specimen for SARS-CoV-2 tests, 2 strategies were developed -“drive-through coronavirus testing station” and “duty resident”. Initially, when inpatient needed to receive PCR tests for SARS-CoV-2, he should be transferred to negative pressure ward. A doctor in charge did oropharyngeal or nasopharyngeal swab to collect the specimen. Then the patient should be isolated in the negative pressure ward until the PCR test was negative. Drive-through coronavirus testing station was set up for collecting specimen since March 17, 2020, and inpatients were allowed to return to their wards immediately after receiving the examination. In addition, 36 medical residents were assigned as duty resident, who was responsible to collect the clinical specimen form inpatients of internal medicine department since March 27, 2020, and every shift was daily.

Between March 2, 2020 and May 3, 2020, 948 cases were detected by quarantine map using information technology. After excluding 699 cases who had received PCR test or infection specialist consultation through chart review by infection case manager, 249 cases remained in remind list (Fig. 2 ). Among them, 93 cases (37%) were in internal medicine department, 55 cases (22%) in surgical department, 63 cases (26%) in pediatrics department, 33 cases (13%) in ICU and 5 (2%) in the other department. After excluding cases in pediatrics department, ICU and the other department, 91 cases (61%) was tested by PCR for SARS-CoV-2. 52 cases (35%) was furtherly consulted by the infection specialist and 15 cases (10%) was cases discharged before tested or consulted among 148 cases in list. Ten inpatients received PCR test after R.R.T 2nd consultation. In the meanwhile, 16 HCWs and 2 caregivers had reported fever and associated respiratory symptoms during the study period. The reasons when the cases did not receive PCR test included infection disease other than COVID-19 (urinary tract infection), fever with non-infection disease (autoimmune or hematology disease), lung infiltration on chest x-ray with non-infection disease (pulmonary edema, lung tumor), or suggestion by infection specialist. There was significant change of testing rate after setting “drive-through coronavirus testing station” and a duty internal medicine resident. The weekly testing rate was 48.1% (13/27) initially, and increased to 84.8% (56/66) for internal medicine department. By contrast, the rate was 62.5% (5/8) initially, and decreased to 36.1% (17/47) for surgical department inpatients, which was still low.

Fig. 2

Study algorithm.

Overall, the PCR test of 91 cases were negative for SARS-CoV-2, and no any cluster or outbreak was screened by quarantine map. By the quarantine map, early surveillance and detection of occult SARS-CoV-2 cases among inpatients, caregivers and RCWs before nosocomial outbreak is extremely important in such a pandemic situation.

Conflict of interest

None.