VIRUS ALERT!
Background
Corona viruses were first identified in humans in the 1960s as the cause of mild, self-limiting diseases of the respiratory tract. Four different genera of ‘common cold' viruses had been identified, which explains to some extent why humans could repeatedly contract these inconvenient infections. Subsequent to this discovery, corona viruses were found to occur in domestic animals and livestock. Although these viruses found in animals caused either diarrhoea or respiratory disease, they were, as in humans, mostly nonlethal, causing production losses. Vaccine research to limit disease in some of these species was ongoing and led to the development of some commercial products to prevent infection and thus reduce production losses.
In a lethal corona virus subsequently named first emerged in China. It caused severe respiratory disease in humans and had a high mortality rate. In another human corona virus named emerged in the Middle East.
