Epidemiological characterization of symptomatic and asymptomatic COVID-19 cases by using RT-PCR tests at a tertiary care hospital, Bhavnagar
Main Article Content
Keywords
RT-PCR testing, COVID-19 infection, transmission rate, asymptomatic carriers
Abstract
Introduction: In December 2019, a new respiratory illness caused by a coronavirus was identified in China, and then it was subsequently named COVID-19. Symptoms may be present or absent in patients which confirmed by COVID-19 RT-PCR tests. Viral loads from asymptomatic and symptomatic COVID-19 infections were found to be similar. This study was conducted at tertiary care hospital, Bhavnagar with the aim of epidemiological characterization of COVID-19 cases regarding its symptom’s presentation using RT-PCR testing.
Material and method: In this retrospective observational study, A total of 985160 samples were received for COVID-19 RT-PCR testing at the Viral Research and Diagnostic Laboratory Centre between March 2020 and September 2023. All samples were analysed for various demographic data.
Results: Of the 985160 samples tested, 22640 (2.29%) samples had positive COVID-19 testing results. Among the positive samples, 36.96% were female and 63.03% were male. The majority of the individuals (40.4%) belonged to the age group of 21–40 years. Of the individuals in a symptomatic condition, 24.43% were symptomatic and 75.56% were asymptomatic.
Conclusion: There are many asymptomatic carriers of COVID-19, and the incidence is high among them. Therefore, continuous surveillance, monitoring, and home isolation of asymptomatic carriers are required to reduce the transmission of infection during the current and future pandemics.
References
1.Tille, Patricia M., Bailey and Scott’s Diagnostic Microbiology. 14th edition. St. Louis, Missouri Elsevier;2017. Pp. 886-887.
2.Parija SC, text book of Microbiology and immunology. 2nd edition. Edited by shrayosee Dutta, Shravan kumar, New Delhi, Elsevier, 2012. Pp. 588-590.
3.Guan Y, Zheng BJ, He YQ, Liu XL, Zhuang ZX, Cheung CL, Luo SW, Li PH, Zhang LJ, Guan YJ, Butt KM. Isolation and characterization of viruses related to the SARS coronavirus from animals in southern China. Science. 2003;302(5643):276-8.
4.Procop, G. W., Church, D. L., Hall, G. S., & Janda, W. M., Konmen E.W., Paul C.S. woods G. L. Koneman’s Color Atlas and Textbook of Diagnostic Microbiology. 7th edition. Edited by Jonathan and John Larkin, Philadelphia: Lippincott, Williams and Wilkins, 2017. Pp. 1523.
5.Apurba S Sastry and Sandhya bhat- textbook of Essentials of medical microbiology, 3rd edition; edited by Deepashree R, Anand J, New Delhi, J.P. medical Ltd; 2021; p.p 660-671.
6.Ananthanarayan and Paniker's textbook of microbiology. 12th edition; Edited by Reba kanungo, India, Universities press private limited; 2022; p.p 403.
7.Topley and Wilson’s Microbiology and microbial infection: virology volume. 10th edition. Edited by Brian W.J. Mahy and Volker ter Meulen. London, Hodder Arnold. 2005; pp. 823-856.
8.Archived: WHO Timeline - COVID-19. World Health Organization. 2020 Apr 27. URL: https://www.who.int/news/item/27-04-2020-who-timeline---covid-19 [accessed 2021-02-01]
9.Mukhida S, Vyawahare C, Verma P, Khan S, Das N. Are the current COVID-19 cases post phase of 3rd wave or pre-phase of 4th wave in India?. Iranian Journal of Medical Microbiology. 2023 Apr 10;17(2):270-2.
10.Origin of SARS-CoV-2. Geneva, Switzerland: World Health Organization; 2020 Mar 26. URL: https://apps.who.int/iris/bitstream/handle/10665/332197/WHO-2019-nCoV-FAQ-Virus_origin-2020.1-eng.pdf [accessed 2021-01-12]
11.Naming the coronavirus disease (COVID-19) and the virus that causes it. World Health Organization. URL: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/technical-guidance/naming-the-coronavirus-disease-(covid-2019)-and-the-virus-that-causes-it [accessed 2021-02-16]
12.Bhosale S, Kulkarni AP. Is a problem shared, a problem halved? Not always! The novel coronavirus COVID-19 outbreak. Indian Journal of Critical Care Medicine: Peer-reviewed, Official Publication of Indian Society of Critical Care Medicine. 2020 Feb;24(2):88.
13.Ministry of health and family welfare. Government of India. As on 31 march 2020 URL: https://www.mohfw.gov.in
14.World Health Organization. Novel-Coronavirus-2019/Events-as-they-happen. 2020 accessed on December 15, 2020 Available from: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/events-as-they-happen
15.https://www.thehindu.com/news/national/other-states/coronavirus-gujarat-reports-first-cases-of-covid-19-infection/article31111847.ece. The Hindu. 19 March 2020. Retrieved 1 April 2020
16.COVID19 guidelines, Department of Health and Family Welfare, Gujarat, Government circulars. COVID19 Guidelines, Govt. of Gujarat, Department of Health and Family Welfare, Gujarat, Government circulars. https://gujhealth.gujarat.gov.in/Portal/News/1095 _1_Implementing-the-COVID-19-Guideline-For-Gujarat-State-170320.PDF
17.World Health Organization. Coronavirus disease 2019 (COVID-19) Situation Report – 46. Available: https://www.who.int/docs/default-source/coronaviruse/situation-reports/20200306- sitrep-46-covid-19.pdf?sfvrsn=96b04adf_4. Accessed June 1 2020.
18.Kannuri S, Patil R, Khan S, Prabhakar V, Das NK, Mukhida S. Correlation between clinical features and immunological parameters with viral load in hospitalised covid positive patients. European Journal of Molecular & Clinical Medicine. 2022; 9 (7) :9116-26.
19.Oran DP, Topol EJ. Prevalence of asymptomatic SARS-CoV-2 infection: a narrative review. Annals of internal medicine. 2020 Sep 1;173(5):362-7.
20.El-Ghitany EM, Hashish MH, Farghaly AG, Omran EA, Osman NA, Fekry MM. Asymptomatic versus symptomatic SARS-CoV-2 infection: a cross-sectional seroprevalence study. Tropical Medicine and Health. 2022 Dec 27;50(1):98.
21.Meda S. Rani, T S. Reddy, ArshiyaNizami G, Kalpana nenavath, Sudha Rani V. Epidemiological characterization of asymptomatic and symptomatic covid-19 cases at a tertiary care hospital, Hyderabad. European Journal of Molecular & Clinical Medicine. 2022; 9(3), 11819–26.
22.Control. NCDC. The updated case definitions and contact-categorization. New Delhi: NCDC, Directorate General of Health Services, Ministry of Health and Family Welfare, Government of India; 2020. http://ncdc.mohfw.gov.in
23.Indian Council of Medical Research. Specimen referral form for COVID-19 (SARS-CoV2). New Delhi: ICMR; 2020. Available from: https://www.icmr.gov.in/pdf/covid/update/ SRF_v9.pdf, accessed on April 30, 2020.
24.Li Q, Guan X, Wu P, Wang X, Zhou L, Tong Y, et al. Early transmission dynamics in Wuhan, China, of novel coronavirus–infected pneumonia. New England journal of medicine. 2020; 382(13):1199-207.
25.Kannuri S, Patil R, Mukhida S, Bhaumik S, Gandham N. A closer look at the link between cycle threshold, clinical features and biomarkers: An observational study in COVID-19 patients. Journal of Family Medicine and Primary Care. 2024 May 1;13(5):1983-9.
26.Bwire GM. Coronavirus: why men are more vulnerable to Covid-19 than women?. SN comprehensive clinical medicine. 2020 Jul;2(7):874-6.
27.Huang C, Wang Y, Li X, Ren L, Zhao J, Hu Y, Zhang L, Fan G, Xu J, Gu X, Cheng Z. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. The lancet. 2020 Feb 15; 395(10223):497-506.
28.Al-Rifai RH, Acuna J, Al Hossany FI, Aden B, Al Memari SA, Al Mazrouei SK, Ahmed LA. Epidemiological characterization of symptomatic and asymptomatic COVID-19 cases and positivity in subsequent RT-PCR tests in the United Arab Emirates. PLoS One. 2021 Feb 12;16(2): e0246903.
29.Kim JK, Crimmins EM. How does age affect personal and social reactions to COVID-19: Results from the national Understanding America Study. PloS one. 2020 Nov 10;15(11):e0241950.
30.Al-Qahtani M, AlAli S, AbdulRahman A, Alsayyad AS, Otoom S, Atkin SL. The prevalence of asymptomatic and symptomatic COVID-19 in a cohort of quarantined subjects. International journal of infectious diseases. 2021 Jan 1;102: 285-8.
31.Petersen I, Phillips A. Three quarters of people with SARS-CoV-2 infection are asymptomatic: analysis of English household survey data. Clinical Epidemiology. 2020 Oct 8:1039-43.
32.Centers for Disease Control and Prevention. COVID-19 and Your Health. Available from: [CDC] (https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/how-covid-spreads.html
33.Johansson MA, Quandelacy TM, Kada S, Prasad PV, Steele M, Brooks JT, Slayton RB, Biggerstaff M, Butler JC. SARS-CoV-2 transmission from people without COVID-19 symptoms. JAMA network open. 2021 Jan 4;4(1): e2035057-.
34.Lavezzo E, Franchin E, Ciavarella C, Cuomo-Dannenburg G, Barzon L, Del Vecchio C, Rossi L, Manganelli R, Loregian A, Navarin N, Abate D. Suppression of a SARS-CoV-2 outbreak in the Italian municipality of Vo’. Nature. 2020 Aug 20;584(7821):425-9.
2.Parija SC, text book of Microbiology and immunology. 2nd edition. Edited by shrayosee Dutta, Shravan kumar, New Delhi, Elsevier, 2012. Pp. 588-590.
3.Guan Y, Zheng BJ, He YQ, Liu XL, Zhuang ZX, Cheung CL, Luo SW, Li PH, Zhang LJ, Guan YJ, Butt KM. Isolation and characterization of viruses related to the SARS coronavirus from animals in southern China. Science. 2003;302(5643):276-8.
4.Procop, G. W., Church, D. L., Hall, G. S., & Janda, W. M., Konmen E.W., Paul C.S. woods G. L. Koneman’s Color Atlas and Textbook of Diagnostic Microbiology. 7th edition. Edited by Jonathan and John Larkin, Philadelphia: Lippincott, Williams and Wilkins, 2017. Pp. 1523.
5.Apurba S Sastry and Sandhya bhat- textbook of Essentials of medical microbiology, 3rd edition; edited by Deepashree R, Anand J, New Delhi, J.P. medical Ltd; 2021; p.p 660-671.
6.Ananthanarayan and Paniker's textbook of microbiology. 12th edition; Edited by Reba kanungo, India, Universities press private limited; 2022; p.p 403.
7.Topley and Wilson’s Microbiology and microbial infection: virology volume. 10th edition. Edited by Brian W.J. Mahy and Volker ter Meulen. London, Hodder Arnold. 2005; pp. 823-856.
8.Archived: WHO Timeline - COVID-19. World Health Organization. 2020 Apr 27. URL: https://www.who.int/news/item/27-04-2020-who-timeline---covid-19 [accessed 2021-02-01]
9.Mukhida S, Vyawahare C, Verma P, Khan S, Das N. Are the current COVID-19 cases post phase of 3rd wave or pre-phase of 4th wave in India?. Iranian Journal of Medical Microbiology. 2023 Apr 10;17(2):270-2.
10.Origin of SARS-CoV-2. Geneva, Switzerland: World Health Organization; 2020 Mar 26. URL: https://apps.who.int/iris/bitstream/handle/10665/332197/WHO-2019-nCoV-FAQ-Virus_origin-2020.1-eng.pdf [accessed 2021-01-12]
11.Naming the coronavirus disease (COVID-19) and the virus that causes it. World Health Organization. URL: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/technical-guidance/naming-the-coronavirus-disease-(covid-2019)-and-the-virus-that-causes-it [accessed 2021-02-16]
12.Bhosale S, Kulkarni AP. Is a problem shared, a problem halved? Not always! The novel coronavirus COVID-19 outbreak. Indian Journal of Critical Care Medicine: Peer-reviewed, Official Publication of Indian Society of Critical Care Medicine. 2020 Feb;24(2):88.
13.Ministry of health and family welfare. Government of India. As on 31 march 2020 URL: https://www.mohfw.gov.in
14.World Health Organization. Novel-Coronavirus-2019/Events-as-they-happen. 2020 accessed on December 15, 2020 Available from: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/events-as-they-happen
15.https://www.thehindu.com/news/national/other-states/coronavirus-gujarat-reports-first-cases-of-covid-19-infection/article31111847.ece. The Hindu. 19 March 2020. Retrieved 1 April 2020
16.COVID19 guidelines, Department of Health and Family Welfare, Gujarat, Government circulars. COVID19 Guidelines, Govt. of Gujarat, Department of Health and Family Welfare, Gujarat, Government circulars. https://gujhealth.gujarat.gov.in/Portal/News/1095 _1_Implementing-the-COVID-19-Guideline-For-Gujarat-State-170320.PDF
17.World Health Organization. Coronavirus disease 2019 (COVID-19) Situation Report – 46. Available: https://www.who.int/docs/default-source/coronaviruse/situation-reports/20200306- sitrep-46-covid-19.pdf?sfvrsn=96b04adf_4. Accessed June 1 2020.
18.Kannuri S, Patil R, Khan S, Prabhakar V, Das NK, Mukhida S. Correlation between clinical features and immunological parameters with viral load in hospitalised covid positive patients. European Journal of Molecular & Clinical Medicine. 2022; 9 (7) :9116-26.
19.Oran DP, Topol EJ. Prevalence of asymptomatic SARS-CoV-2 infection: a narrative review. Annals of internal medicine. 2020 Sep 1;173(5):362-7.
20.El-Ghitany EM, Hashish MH, Farghaly AG, Omran EA, Osman NA, Fekry MM. Asymptomatic versus symptomatic SARS-CoV-2 infection: a cross-sectional seroprevalence study. Tropical Medicine and Health. 2022 Dec 27;50(1):98.
21.Meda S. Rani, T S. Reddy, ArshiyaNizami G, Kalpana nenavath, Sudha Rani V. Epidemiological characterization of asymptomatic and symptomatic covid-19 cases at a tertiary care hospital, Hyderabad. European Journal of Molecular & Clinical Medicine. 2022; 9(3), 11819–26.
22.Control. NCDC. The updated case definitions and contact-categorization. New Delhi: NCDC, Directorate General of Health Services, Ministry of Health and Family Welfare, Government of India; 2020. http://ncdc.mohfw.gov.in
23.Indian Council of Medical Research. Specimen referral form for COVID-19 (SARS-CoV2). New Delhi: ICMR; 2020. Available from: https://www.icmr.gov.in/pdf/covid/update/ SRF_v9.pdf, accessed on April 30, 2020.
24.Li Q, Guan X, Wu P, Wang X, Zhou L, Tong Y, et al. Early transmission dynamics in Wuhan, China, of novel coronavirus–infected pneumonia. New England journal of medicine. 2020; 382(13):1199-207.
25.Kannuri S, Patil R, Mukhida S, Bhaumik S, Gandham N. A closer look at the link between cycle threshold, clinical features and biomarkers: An observational study in COVID-19 patients. Journal of Family Medicine and Primary Care. 2024 May 1;13(5):1983-9.
26.Bwire GM. Coronavirus: why men are more vulnerable to Covid-19 than women?. SN comprehensive clinical medicine. 2020 Jul;2(7):874-6.
27.Huang C, Wang Y, Li X, Ren L, Zhao J, Hu Y, Zhang L, Fan G, Xu J, Gu X, Cheng Z. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. The lancet. 2020 Feb 15; 395(10223):497-506.
28.Al-Rifai RH, Acuna J, Al Hossany FI, Aden B, Al Memari SA, Al Mazrouei SK, Ahmed LA. Epidemiological characterization of symptomatic and asymptomatic COVID-19 cases and positivity in subsequent RT-PCR tests in the United Arab Emirates. PLoS One. 2021 Feb 12;16(2): e0246903.
29.Kim JK, Crimmins EM. How does age affect personal and social reactions to COVID-19: Results from the national Understanding America Study. PloS one. 2020 Nov 10;15(11):e0241950.
30.Al-Qahtani M, AlAli S, AbdulRahman A, Alsayyad AS, Otoom S, Atkin SL. The prevalence of asymptomatic and symptomatic COVID-19 in a cohort of quarantined subjects. International journal of infectious diseases. 2021 Jan 1;102: 285-8.
31.Petersen I, Phillips A. Three quarters of people with SARS-CoV-2 infection are asymptomatic: analysis of English household survey data. Clinical Epidemiology. 2020 Oct 8:1039-43.
32.Centers for Disease Control and Prevention. COVID-19 and Your Health. Available from: [CDC] (https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/how-covid-spreads.html
33.Johansson MA, Quandelacy TM, Kada S, Prasad PV, Steele M, Brooks JT, Slayton RB, Biggerstaff M, Butler JC. SARS-CoV-2 transmission from people without COVID-19 symptoms. JAMA network open. 2021 Jan 4;4(1): e2035057-.
34.Lavezzo E, Franchin E, Ciavarella C, Cuomo-Dannenburg G, Barzon L, Del Vecchio C, Rossi L, Manganelli R, Loregian A, Navarin N, Abate D. Suppression of a SARS-CoV-2 outbreak in the Italian municipality of Vo’. Nature. 2020 Aug 20;584(7821):425-9.
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Sep 30, 2026
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Dr. Nehalben J. Patel, Dr. Kairavi Desai, Dr. Mihirkumar K Oza, & Dr. Saklainhaider S Malek. (2026). Epidemiological characterization of symptomatic and asymptomatic COVID-19 cases by using RT-PCR tests at a tertiary care hospital, Bhavnagar. Journal of Population Therapeutics and Clinical Pharmacology, 32(11), 2607-2616. https://doi.org/10.67145/rqqysm55
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All articles published in JPTCP are licensed under Copyright Creative Commons Attribution-NonCommercial 4.0 International License.
How to Cite
Dr. Nehalben J. Patel, Dr. Kairavi Desai, Dr. Mihirkumar K Oza, & Dr. Saklainhaider S Malek. (2026). Epidemiological characterization of symptomatic and asymptomatic COVID-19 cases by using RT-PCR tests at a tertiary care hospital, Bhavnagar. Journal of Population Therapeutics and Clinical Pharmacology, 32(11), 2607-2616. https://doi.org/10.67145/rqqysm55
