Epidemiology of Corona Virus

David Braun^*
*Correspondence: David Braun, Department of Laboratory Medicine and Pathology, University of Rochester, Rochester, USA, Email:

Description

Human coronaviruses were found by enzyme linked immunosorbent assay in upper tract secretions taken during 30% of 108 acute respiratory infections experienced by 30 children under age 6 years with recurrent respiratory infections and during 29% of 51 acute infections experienced by their siblings. Lower respiratory tract infection-predominantly wheezy bronchitis occurred in 30% of the index children's coronavirus positive infections but in none of their siblings' infections.

The coronavirus belongs to a family of viruses which will cause various symptoms like pneumonia, fever, breathing difficulty, and lung infection. These viruses are common in animals worldwide, but only a few cases are known to affect humans. The World Health Organization (WHO) used the term 2019 novel coronavirus to ask a coronavirus that affected the lower tract of patients with pneumonia in Wuhan, China on 29 December 2019. The WHO announced that the official name of the 2019 novel coronavirus is coronavirus disease (COVID-19). And the current reference name for the virus is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It was reported that a cluster of patients with pneumonia of unknown cause was linked to an area Huanan South China Seafood Market in Wuhan, Hubei Province, China in December 2019.

Epidemiology

The impact of an epidemic depends on the amount of infected persons, transmissibility, and therefore the clinical severity of the infection. The world needs to expand public health activities, social and economic planning in reference to the SARS-CoV-2, and reduced the impact on public health, social and economic well-being of the people. Till March end, the epidemiology of COVID-19 wasn't very clear. Now, with increasing information on the epidemiology of COVID-19, the newly affected parts, including India, evolved with the concept of lockdown and reduced the transmission as an efficient way to curb the transmission.

Epidemiological studies in Wuhan at the start of the outbreak identified an initial association with a seafood market that sold live animals for food purposes, where most of the first patients had worked or at least visited there. The market was traced because the source, and subsequently, the market was closed for disinfection. However, because the outbreak progressed, person-to-person spread became the first mode of transmission.

The respiratory droplets released during cough, sneezing, talks, and mucus secretion are the dominant medium of transmission. The infection occurs if an individual inhales such droplets or touches the contaminated surface with droplets and, subsequently, their own eyes, nose, and mouth. The droplets don't travel quite 6 feet and don't linger within the air also. The aerosol spread is uncommon; however, the aerosol-generating procedures like intubation, suction, nebulization, etc., may transmit the disease. However, a report revealed that SARS-CoV-2 might remain viable in aerosols under experimental conditions for a minimum of three hours. The possibility of transmission is higher within the first phase as soon as symptoms appear because the viral RNA peaks during that period. However, it may transmit during the incubation period as well. The time period is usually within fortnight of exposure, with the bulk occurring within 4-5 days of exposure.