The recent challenges of highly contagious COVID-19; causing respiratory infections: symptoms, diagnosis, transmission, possible vaccines, animal models and immunotherapy.

COVID-19 is highly contagious pathogenic viral infection initiated from Wuhan seafood wholesale market of China on December 2019 and spread rapidly around the whole world due to onward transmission. This recent outbreak of novel coronavirus (CoV) was believed to be originated from bats and causing respiratory infections such as common cold, dry cough, fever, headache, dyspnea, pneumonia and finally Severe Acute Respiratory Syndrome (SARS) in humans. For this widespread zoonotic virus, human-to-human transmission has resulted in nearly 83 lakh cases in 213 countries and territories with 4,50,686 deaths as on 19th June 2020. This review presents a report on the origin, transmission, symptoms, diagnosis, possible vaccines, animal models and immunotherapy for this novel virus and will provide ample references for the researchers towards the ongoing development of therapeutic agents and vaccines and also preventing the spread of this disease.