Viral outbreaks are not new; we have faced SARS, MERS, Nipah, Zika, and several other viral outbreaks in the recent past. However, none has made the world stand still as COVID-19 has. The World Health Organization (WHO) has declared this outbreak a pandemic due to its high transmission rate; as of 2 April 2020, more than 950,000 cases have been reported, of which more than 48,000 patients have died. The number of cases and deaths continues to rise as it has spread to over 200 countries and territories, making it a global concern. A drug or vaccine that will help end this pandemic is needed. The diagnostics community continues to aggressively research and innovate for SARS-CoV-2 solutions. The latest this week includes research on saliva-based detection, CRISPR diagnostics, serological testing, and much more.
COVID-19 is a beta coronavirus, similar to the human coronaviruses SARS and MERS. With this novel outbreak, there are now seven different strains of human coronaviruses (HCoVs): the 229E and the NL63 strains of HCoVs (alpha coronaviruses), OC43, HKU1, SARS, MERS, and COVID-19 HCoVs (beta coronaviruses).
As the world braces to fight the global pandemic through social distancing and country-wide lockdown, here’s a snapshot of how advances in laboratory diagnostics could efficiently contribute to counteract this and other (future) viral outbreaks that will help transform human lives affected by COVID-19:
Despite there being clear evidence that laboratory tests are vital for improving the care and/or maintaining the wellness of people, there are at least three areas wherein vitro diagnostics can provide essential contributions to the diagnostic reasoning and managed care of patients with suspected or confirmed SARS-CoV-2 infection:
The etiological diagnosis of SARS-CoV-2 is the first and most obvious setting where laboratory diagnostics plays an essential role. Both the WHO and the US Centers for Disease Control and Prevention (CDC), along with other national and international scientific organizations, have timely released detailed information for in-house development of reverse transcription-polymerase chain reaction (RT-PCR) tests, which have hence been straightforwardly implemented by many reference laboratories worldwide and are now undergoing clearance by many regulatory agencies.
The second essential contribution that laboratory medicine could provide in the diagnostics of 2019-nCoV infection encompasses staging, prognostication, and therapeutic monitoring of COVID-19. Not only RT-PCR tests will be vital for verifying the course of the infection, as well as the possible presence and extent of viremia, but many other laboratory tests may help to assess disease severity and to predict the risk of evolution toward ARDS, DIC and/or MOF.
A third, though not less, essential support given by diagnostic testing to counteracting viral outbreaks is the identification of anti-SARS-CoV-2 antibodies, both immunoglobulin G (IgG) and M (IgM). Although serology testing cannot be typically advocated as a reliable surrogate of RT-PCR for diagnosing acute viral infections, it maintains an essential role for both investigational and surveillance purposes. Notably, a combined IgM-IgG rapid immunoassay has also been recently developed, which is apparently characterized by better diagnostic accuracy (i.e. up to 89% sensitivity and up to 91% specificity) than either IgM or IgG test alone. Widespread application of this and other rapid serological tests may hence enable to gain valuable epidemiological data in the fight against this viral epidemic.
The managed care of patients with SARS-CoV-2 infection entails early identification, rapid isolation, the timely establishment of infection prevention and control (IPC) measures, together with symptomatic care for patients with mild disease and supportive treatment for those with severe COVID-19. It is quite evident that laboratory medicine will increasingly provide an essential contribution to the diagnostic reasoning, managed care, and therapeutic monitoring of the vast majority of human diseases, thus including infectious diseases, and COVID-19, which has now been defined as global health emergency by the WHO.