A comprehensive review of pathogenesis and pathophysiology of covid- 19 infection

Coronavirus (COVID-19) which is also known as Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), is the major global health threat. It originated from a city of China named as Wuhan in December 2019 and has been emerging since then worldwide as over more than 190 countries have got affected. COVID-19 has been declared as a Global Health Pandemic by World Health Organization (WHO) on March 11 as till date, 162,553,554 infected patients and 3,371,971 deaths have been recorded worldwide. The symptoms of Coronavirus include fever, cough, myalgia and severe respiratory failure and the diagnosis is confirmed using reverse transcriptase PCR (RT-PCR) test. Till date, no specific treatment is available to deal with this global health pandemic and health system all over the world is trying its best to deal with it and combat it. However, the existing drug therapy provides limited success and is found to be unsatisfactory. In orde0r to eradicate infection, the worldwide focus is on development of vaccine. To prevent the spread of infection, some precautionary and supportive measures such as social distancing, self-quarantine, avoid crowded places, avoid travelling unnecessarily are being practiced and exercised, besides, probationary drug therapy. At the initial stages due to state of emergency many patients have been treated with antiviral drugs, antibacterial drugs and corticoids such as lopinavir, ritonavir , chloroquine(CQ), hydroxychloroquine (HCQ), remdesivir, favipiravir, ribavirin, interferons(IFN’s), corticosteroids, oseltamivir etc. This study outlines the types of COVID-19 vaccines, strengths and shortcomings of every COVID-19 vaccine development platformand analyses the challenges ahead.