Globally, on the 30th January 2020 the World Health Organization (WHO) of the United Nations declared the pandemic a public health emergency of international concern. In 2020 as upto on 28th March, WHO was discovered globally, Corona virus infecting 663748 people and killing 30880 people. This defines the outbreak an “extraordinary event which is determined to constitute a public health risk to other States through the international spread of disease and to potentially require a coordinated international response”.
Several countries and airlines immediately suspended travel from affected areas, closed some borders with China, and initiated comprehensive preventative screening at airports. “on the 30th January 2020 the World Health Organization (WHO) of the United Nations declared the pandemic a public health emergency of international concern”. Early on, the Chinese authorities revealed that the outbreak was caused by a Novel beta-coronavirus, named 2019-nCoV. This was soon found to be significantly genetically related to SARS-CoV and other bat Coronaviruses.
Globally, as on 17 April 2020, a total of 2231438 have been reported worldwide; These include 564718 who have been cured/discharged and 15837 deaths. This condition have had gradually goes to more severe, and as on 6 May 2021, there have been 154,815,600 confirmed cases of COVID-19, including 3,236,104 deaths, reported to World Health Organization.
The initial cases were associated with a seafood market in Wuhan where live animals were sold. This suggested a possible animal reservoir for this virus and suggested zoonotic (animal to human) transmission. Later on, environmental samples obtained from this market were found to be positive for 2019-nCoV, strengthening the hypothesis that this is a zoonotic virus. However, whilst the virus was found to have originally started among infected animals, most of the subsequently reported cases were shown to be caused by human-to-human transmission.
Beta-coronaviruses have caused major epidemics in the last 2 decades. In 2003, SARS-CoV was discovered in China before being spread globally, infecting 8,098 people and killing 774. This was later found to be zoonotic in origin and thought to have started amongst a bat reservoir before later infecting wild civet cats and raccoon dogs that were being sold at live wild animal markets destined for human consumption. In 2012, MERS-CoV was discovered in Saudi Arabia before also spreading globally resulting in 2506 confirmed cases and killing 862 people worldwide. Again, this started as a zoonotic virus, shown to move from camels to humans and again thought to have initially emerged from bats. Imported cases of 2019-nCoV infection in travellers have been detected in the U.S. Person-to-person spread of 2019-nCoV also has been seen among close contacts of returned travellers from Wuhan, but at this time, this virus is NOT currently spreading in the community in the United States.