Recent world is in an era of global pandemic Coronavirus disease (COVID-19) that testing the community to survive as said by the Darwinian evolutionary theory "Survival of the fittest". Coronavirus disease (COVID-19) has become a challenge for the scientific community and researchers because there are no specific vaccines or treatments available for disease and not any existing therapeutic approach has proven its significance in combating the disease. In December 2019 Wuhan city of China has emerged as origin point for disease. Since then the scientific community is trying to find a solution to fight with Coronavirus disease (COVID-19). Few of the existing antiviral and antimalarial drugs has shown some potential but there are no clinical studies in support of the drugs. This is the time that motivates us as a researcher to explore more to make our contribution in the field of science.

There is a new public health crisis threatening the world with the emergence and spread of 2019 novel corona virus (2019-nCoV) or the severe acute respiratory syndrome corona virus 2 (SARS-CoV-2). The virus was first found in bats and was transmitted to humans through yet unknown intermediary animals in Wuhan, Hubei province, China in December 2019. There have been around 6,589,291 reported cases of corona virus disease 2019 (COVID-2019) and 388,317 reported deaths to date 04/06/2020 in world wide. The transmission of disease is by inhalation or contact with infected droplets and the incubated period ranges from 2 to 14 d. The COVID-19 symptoms are start with fever, cough, sore throat, breathlessness, fatigue, malaise among others. The disease is occur in most people and it may progress to pneumonia, acute respiratory distress syndrome (ARDS) and multi organ dysfunction. Many people are asymptomatic. The fatality rate of COVID-19 is estimated to range from 11-12%. In this review signs and symptoms of virus, prevention of COVID-19 and suggestive medicinal value of south Indian plant sources has been reported. Though the varieties of improved approaches have been taken in scientific and medicinal concern, we have to pay attention on medicinal value of the plant based sources to prevent these types of endemic diseases. Treatment is essentially supportive; role of antiviral agents is yet to be established, in order to overcome this some of the most effective medicinal plants with immune enhancing properties according to the native ethno botanical documents has been reported. Based on the available evidence of the studies on ethnobotany, certain medicinal plants such as Cayratia trifolia, Azadirachta indica, Andrographis paniculata, Ficus religiosa, Curcuma longa, Sesbania grandiflora, Zingiber officinale, Punica granatum, Phyllanthus amarus and Avicennia marina they are inexpensive but also for better cultural acceptability, better compatibility with the human body and minimal side effects. This review gives an overview of some important medicinal plants with antiviral activities which are traditionally used in India.

The China Health Authority alerted the World Health Organization (WHO) to several cases of pneumonia of unknown aetiology in Wuhan City in Hubei Province in central China On December 31, 2019. Since December 8, 2019, the cases had been reported, and many patients worked at or lived around the local Human Seafood Wholesale Market although other early cases had no exposure to this market. So far, on January 7, a novel Coronavirus was identified from the throat swab sample of a patient. This novel virus originally abbreviated as 2019-nCoV by WHO. By the Coronavirus Study Group, this pathogen was later renamed as severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) and by the WHO, the disease was named Coronavirus disease 2019 (COVID-19).

Solubility proves to be a major obstacle for the successful growth and commercialization of new drug products. Since 40% of the active substances being recognized through the new example in high - throughput screening are lipophilic. So, its feasibility as a possible new drug candidate reduces many. Because of this restraint, numerous pharmacologically active molecules have unsuccessful to attain the market. Therefore, Nanosuspensions have emerged as a promising approach for the competent delivery of hydrophobic drugs because of their multipurpose features and unique advantages. Technique like media milling and high stress homogenization has been used commercially for produce nanosuspensions. In latest times, the manufacturings of nanosuspensions spend emulsions and microemulsions as pattern have been dealed within the literature. A nanosuspension not only determines the troubles of poor solubility and bioavailability, but also modifies the pharmacokinetics of drug and thus progress drug safety and efficacy. These review articles explain the training methods, characterization and purpose of the nanosuspension.

The corona virus disease 2019 (COVID-19) is ongoing pandemic caused by SARS-CoV2. It was first identified in Wuhan, China in Dec 31, 2020. As of June 8, 2020, 69, 31,000 confirmed cases, 4, 00,857 confirmed death around 216 countries areas or territories with cases have been reported by WHO. The clinical trial of COVID-19 is going on Hydroxychloroquine, Azithromycin are given alone and combination and a new antiviral agent Ramdesivir help to some infection. However there is still no available vaccine and potential treatment for this corona virus. These COVID-19 pathogenesis pathways are still unknown. In this literature review we discussed about CoV, SARS-MERS CoV, COVID-19, Clinical manifestation, illness and risk factor, treatment, preventive measures, control the transmission.