Indian Journal of Community Medicine

ORIGINAL ARTICLE
Year
: 2020  |  Volume : 45  |  Issue : 3  |  Page : 278--282

Initial viral load of a COVID-19-infected case indicated by its cycle threshold value of polymerase chain reaction could be used as a predictor of its transmissibility - An experience from Gujarat, India


Bidisa Sarkar1, Rabindra Nath Sinha2, Kamalesh Sarkar3 
1 Department of Community Medicine, Kallinga Institute of Medical Sciences, Kushabhadra Campus, Bhubaneswar, Odisha, India
2 Department of Maternal and Child Health, All India Institute of Hygiene and Public Health, Kolkata, West Bengal, India
3 Director, ICMR-National Institute of Occupational Health, Ahmedabad, Gujarat, India

Correspondence Address:
Dr. Kamalesh Sarkar
ICMR-National Institute of Occupational Health, Meghani Nagar, Ahmedabad - 380 016, Gujarat
India

Background: Transmission dynamics of the infectious disease Corona Virus Disease - 19 (COVID-19) is yet to be understood fully. The study aimed at exploring whether quantitative viral load of COVID-19-infected case indicated by cycle threshold (Ct) value of real-time reverse transcription polymerase chain reaction could predict about transmission pattern in the community. Materials and Methods: An observational study was conducted involving 1976 individuals, suspected to be suffering from COVID-19 and contacts, of laboratory confirmed cases from selected districts of Gujarat, India. A total of 138 persons were detected to be positive. Weekly positivity showed an overall increasing trend during the studied weeks. It was observed that only 7% had high, 9% as moderate and rest, 84% had low viral load based on Ct values of real-time RT-PCR. Results: Most secondary cases clustered around index cases with high viral load whereas fewer secondary cases clustered around index cases with low viral load. Each index high viral load case transmitted an average of 6.25 secondary cases whereas the same of low viral load transmitted an average of 0.8 case. Conclusion: If cases with higher viral load are selectively isolated on detection from the rest of the community along with contact tracing of all individuals, who came in contact with them during the previous 5 days, the quantum of transmission will reduce subsequently. Moreover, health-care workers often get infected while working, probably due to the fact that they often handle cases with higher viral load. The Ct value of all may be provided along with test report to safeguard everybody's health including health-care workers.


How to cite this article:
Sarkar B, Sinha RN, Sarkar K. Initial viral load of a COVID-19-infected case indicated by its cycle threshold value of polymerase chain reaction could be used as a predictor of its transmissibility - An experience from Gujarat, India.Indian J Community Med 2020;45:278-282


How to cite this URL:
Sarkar B, Sinha RN, Sarkar K. Initial viral load of a COVID-19-infected case indicated by its cycle threshold value of polymerase chain reaction could be used as a predictor of its transmissibility - An experience from Gujarat, India. Indian J Community Med [serial online] 2020 [cited 2021 May 8 ];45:278-282
Available from: https://www.ijcm.org.in/article.asp?issn=0970-0218;year=2020;volume=45;issue=3;spage=278;epage=282;aulast=Sarkar;type=0