Introduction
In late December 2019, Chinese health authorities investigated a cluster of atypical pneumonia cases occurring primarily in individuals who had visited a seafood and wet market in Wuhan, Hubei Province, China. Patients reported fever and cough, and most developed chest discomfort and/or respiratory distress, with a diagnosis of pneumonia being made by chest radiographs and/or computed tomographic (CT) scan (1). After testing for common causes of respiratory infection yielded negative results, unbiased sequencing of bronchoalveolar lavage (BAL) fluid identified a variant beta-coronavirus with nearly 85% sequence homology to that of a bat severe acute respiratory syndrome (SARS)-like coronavirus (CoV) (1). The virus was subsequently isolated in eukaryotic cell culture, and further characterization showed it to be distinct from SARS-CoV and Middle East respiratory syndrome (MERS)-CoV, with sequence homology of approximately 79% and about 50%, respectively (2). The variant CoV, which has been named SARS-CoV-2 by the International Committee on Taxonomy of Viruses (3), represents the seventh CoV to cause disease in humans, and the third CoV since 2003 to cross over from animals to humans and be associated with severe respiratory illness (1). The World Health Organization (WHO) has named the illness caused by SARS-CoV-2 coronavirus disease-2019 (COVID-19).
To date, there have been approximately 95 000 confirmed cases of COVID-19 in over 80 different countries. However, the majority of cases (about 85%) have occurred in mainland China. Following an incubation period ranging from 2 to 13 days, most (>80%) symptomatic patients have reported a fever and cough, and some have developed shortness of breath (4). Although COVID-19 is generally thought to be a milder illness compared to SARS and MERS-CoV, nearly 3200 deaths have occurred, yielding a case-fatality rate of about 3% (versus approximately 10% for SARS-CoV and approximately 35% for MERS-CoV) (5). This mortality rate is likely an overestimation, due to the high probability that many infected individuals have not sought medical attention and laboratory confirmation (6). It is important to emphasize that details regarding this outbreak are rapidly evolving, and therefore, the full extent of COVID-19’s impact is still unknown. That being said, the nonspecific clinical features of COVID-19, along with the co-circulation of other respiratory viruses (e.g., influenza, respiratory syncytial virus) in many parts of the world, have presented a major challenge to public health officials and healthcare providers. This outbreak represents an opportunity for government agencies, the public health sector, industry, and clinical laboratories to partner and develop a robust and sustainable system that would allow for rapid development, production, dissemination, and implementation of diagnostic tests for infectious agents of global health concern.