NEW DELHI: The first study from India documenting a cluster of Covid-19 has reconfirmed higher rates of transmission among close contacts and has reinforced that public health measures such as physical distancing, personal hygiene, and infection control measures are necessary to prevent transmission.
The report titled “A cluster of SARS-CoV-2 infection among Italian tourists visiting India, March 2020” published in the Indian Council of Medical Research’s Indian Journal of Medical Research analysed a group of 23 Italian tourists, who along with 3 Indians visited several tourist sites before 17 of them were detected to be infected.
Of the nine who developed symptoms, six were mild, one was severe and two were critically ill who later died, said the report prepared by epidemiologists with the ICMR and clinicians in Gurugram and Jaipur who treated these patients.
The researchers have investigated this cluster to describe the epidemiological, clinical, radiological and laboratory findings.
“Our analysis reinforces the need to ensure early detection and aggressive contact tracing in order to contain the outbreak,” said Dr. Tarun Bhatnagar, a scientist with the ICMR’s National Institute of Epidemiology who co-authored the study.
The investigation has shown that the median duration between the day of confirmation for COVID-19 and RT-PCR negativity was 18 days with a range of 12-23 days and two patients died with a case fatality of 11.8 per cent within the cluster.
The first patient, 69-year-old male, resident of Lombardy in Italy and family physician by profession had developed fever, cough and difficulty in breathing on February 23 within two days of arriving in India however it was five days later, after his condition deteriorated that he was tested for SARS CoV 2 at the SMS Medical College, Jaipur.
Seventeen of the 25 other persons who were all asymptomatic at that time, including his wife, tested positive.
“The median age of the COVID-19-positive individuals was 69 year and nine (52.9%) were female. Of the 17 patients, nine (52.9%) had or developed symptoms, whereas eight (47.1%) did not show any symptoms,” said the report.
Among the affected, one had symptoms of COVID-19 on day 0 of hospitalization and six developed symptoms by day 3, while two became symptomatic by day 8. By day 12, symptoms subsided in all the mild patients, it added.
The most common symptoms were fever (66.7%), cough (44.4%), and sore throat (33.3%). The median interval between the day of confirmation for COVID-19 and RT-PCR negativity was 18 days. The median duration of hospital stay was 20 days with a range of 14-37 days.
Eleven of the 17 (64.7%) had any chronic comorbidities, the most common being hypertension, dyslipidaemia or high blood cholesterol levels, and diabetes. Of the seven who had hypertension, two progressed to severe critical illness, whereas one became RT-PCR negative on day 23.