Secondary attack rate of COVID-19: analysis of contacts of COVID-19 cases admitted in a tertiary care centre, Northern district of Kerala, India-a cross-sectional study

Authors

  • Anitha S. Saraswathy Department of Community Medicine, Government Medical College, Kannur, Kerala, India
  • Rameela Sanya Department of Community Medicine, Government Medical College, Kannur, Kerala, India
  • Jayasree A. Kumaran Department of Community Medicine, Government Medical College, Kannur, Kerala, India

DOI:

https://doi.org/10.18203/2394-6040.ijcmph20205193

Keywords:

COVID-19, Kerala, Secondary attack rate, Secondary clinical attack rate, Secondary infection rate

Abstract

Background: Secondary attack rate is the proportion of primary contacts that develop infection or symptom within one incubation period after contact with an index case. The secondary attack rate will help in studying and understanding the transmission dynamics of infectious diseases. As coronavirus disease (COVID-19) is a novel disease which has resulted in a pandemic, understanding the transmission dynamics is very important for strengthening preventive measures.

Methods: The present cross-sectional study was conducted to estimate the secondary attack rate among primary contacts of COVID-19 cases admitted in a tertiary care centre in Northern Kerala. Secondary attack rate was calculated as the percentage of primary contacts that tested positive for COVID-19 with RT-PCR test within 14 days of exposure.

Results: Secondary attack rate was found to be 5.88%, secondary clinical attack rate 2.35% and secondary infection rate 3.53%. Among those contacts that developed disease, 80% were household contacts.

Conclusions: Secondary attack rate was 5.88% and household contacts were the majority to get the disease.

Author Biographies

Anitha S. Saraswathy, Department of Community Medicine, Government Medical College, Kannur, Kerala, India

Assistant Professor
Department of Community Medicine
Government Medical College Kannur,
Kerala, India

Rameela Sanya, Department of Community Medicine, Government Medical College, Kannur, Kerala, India

Junior resident
Department of Community Medicine
Government Medical College Kannur
Kerala India

Jayasree A. Kumaran, Department of Community Medicine, Government Medical College, Kannur, Kerala, India

Professor and Head of the Department
Department of Community Medicine
Government Medical College Kannur
Kerala India

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Published

2020-11-25

How to Cite

Saraswathy, A. S., Sanya, R., & Kumaran, J. A. (2020). Secondary attack rate of COVID-19: analysis of contacts of COVID-19 cases admitted in a tertiary care centre, Northern district of Kerala, India-a cross-sectional study. International Journal Of Community Medicine And Public Health, 7(12), 5111–5114. https://doi.org/10.18203/2394-6040.ijcmph20205193

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Section

Original Research Articles