Corona Virus: A Review Article

Abstract

Corona viruses are a category of enveloped viruses from the corona virus family ,different by their large non-segmented positive -sense , single strand RNA genomes. These viruses can cause a spectrum of illnesses ,ranging from the cold to more severe conditions such as SARS and MERS March 2020 health organization declared the pandemic of the SARS -COV -2 virus ,which first appeared in late 2019 ,a global pandemic situation arose. An analysis of existing scholarly works illuminates various aspects of the resulting disease, COVID -19 , including its history ,symptoms ,epidemiology ,clinical features ,diagnosis, therapeutic approaches , and prevention strategies

Introduction

COVID-19, caused by SARS-CoV-2, emerged in China in December 2019 and rapidly became a global pandemic. India reported its first case on January 27, 2020. The country experienced fluctuating case numbers, with a decline from September 2020 to early January 2021 after the first wave, followed by a severe second wave fueled by viral variants, resulting in high fatalities. SARS-CoV-2 enters human cells via ACE2 receptors, primarily in the lower respiratory tract, and belongs to the beta-coronavirus genus, often originating from animals like bats and pangolins. Ongoing research is essential for understanding transmission, vaccine development, treatment, and public health interventions.

Symptoms
Common symptoms include fever, dry cough, and fatigue. Less frequent signs may include loss of taste or smell, nasal congestion, sore throat, headache, muscle/joint pain, rashes, nausea, diarrhea, or dizziness. Severe infection can cause shortness of breath.

Epidemiology and Transmission
COVID-19 spreads mainly via respiratory droplets, including from asymptomatic individuals. Human coronaviruses have existed for decades, causing 5–10% of acute respiratory infections. Viral shedding can last 17–24 days on average, sometimes longer in feces. Understanding transmission dynamics, risk factors, and disease outcomes helps guide public health strategies.

Diagnosis
Diagnosis combines clinical evaluation, laboratory tests (RT-PCR, antigen tests, serology), and imaging (X-ray, CT scans). RT-PCR is the gold standard, while rapid antigen and antibody tests provide supplementary information. Challenges include false negatives, false positives, and test variability. Future approaches include point-of-care and multiplex testing.

Treatment
Treatment includes antivirals (Remdesivir, Molnupiravir), corticosteroids (Dexamethasone), immunomodulators (Tocilizumab, Baricitinib), oxygen therapy, anticoagulation, and supportive care. Monoclonal antibodies and convalescent plasma are used in certain cases. Vaccination is critical, with mRNA vaccines (Pfizer, Moderna), viral vector vaccines (AstraZeneca, J&J), and protein subunit vaccines (Novavax) showing high efficacy.

Prevention
Preventive measures involve:

• Personal: Mask-wearing, hand hygiene, physical distancing, avoiding close contact.

• Community: Vaccination, testing, contact tracing, social distancing.

• Environmental: Surface disinfection, proper ventilation.

• Public Health: Travel and gathering restrictions, clear communication.

Conclusion

The COVID-19 pandemic has presented significant challenges to global health, economies, and societies. Through a comprehensive review of the literature, this article has highlighted the key aspects of COVID-19, including its epidemiology, pathogenesis, diagnosis, treatment, prevention, and vaccination strategies.

References

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Copyright

Copyright © 2025 Nupura Upadhye . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.