Concluding remarks
The emergence of any novel virus, in particular one that can be transmitted via the respiratory route, has to be taken seriously. A rapid response, a united global front and mobilization of resources and expertise are our best tools in preventing or reducing the devastation that some of these viruses can cause. This is exemplified by the recent events that have led to the recognition and isolation of the novel coronavirus responsible for acute respiratory illness. Within weeks of the first report, a PCR-based diagnostic assay was made available [1], a preliminary case definition [39] and incubation period was issued [40], the virus was fully sequenced [4], the detection of new cases was rapidly communicated to the health authorities and more recently, guidelines for handling and working with this virus have been issued [24]. The novel coronavirus is the 6th member of the human coronaviruses and the third to be isolated in the last ten years. Based on current information, NCoV does not appear to transmit easily or sustainably between people, but it can lead to serious lower respiratory tract infection and renal failure. The mode of transmission has not been conclusively identified, although respiratory route looks most likely. A study which is in press, has shown that a number of different bat species resident in Ghana and parts of Europe are infected with coronaviruses very similar to NCoV, in some cases differing by less than 2% at the genetic level [41]. These findings suggest that NCoV is most likely to have arisen from bat viruses. However, a number of pertinent questions remain unanswered: Does NCoV represent an interspecies jump of a bat coronavirus? How did humans acquired the infection? Was it a direct infection from bats to humans or did it involve an intermediate host such as domestic animals? Are the virus isolates from all infected persons genetically identical? Do NCoV genetic variants exits in the human population, but cause mild or asymptomatic infections? Future studies will no doubt attempt to address these and other related questions. For the time being, surveillance and thorough investigations of cases with unexplained severe respiratory illness, particularly in those residing in or returning from Middle East, is being recommended [24].