key: cord-256159-7x45wd45
authors: McFee, R.B.
title: INTRODUCTION - EMERGING PATHOGESN AND THE COVID-19 PANDEMIC
date: 2020-07-28
journal: Dis Mon
DOI: 10.1016/j.disamonth.2020.101065
sha: 
doc_id: 256159
cord_uid: 7x45wd45

nan

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As recent events with COVID-19 (SARS2-Cov, SARS-COV-2), demonstrated, coronaviruses are capable of significant human illness (1-10). Historically coronaviruses have been considered low pathogenic viruses. That changed with SARS in 2003 when the first highly pathogenic coronavirus was discovered. SARS caused severe pulmonary illness, and was associated with a case fatality rate ~9%. With further study into SARS and other human pathogenic coronaviruses, it became clear these highly adaptive viruses should be added to the list of pathogens capable of causing major outbreaks.

Since SARS, two additional highly pathogenic coronaviruses have emerged, MERS, and SARS2 (8-10), which throughout this article will be referred to as COVID-19 (5) (6) (7) (8) . This latest potentially deadly coronavirus, which emerged in late 2019, has caused a level of global illness unseen in numbers and rapidity since the major outbreaks of the early 19 th century. According to the World Health Organization, as of 9 June 2020, COVID-19 has resulted in 7,039,918 confirmed cases and 404,396 deaths worldwide, 3,366,251 cases in the Americas, with 140,498 deaths. Of concern in some regions the number of cases continues to rise (11, 12) .

Also worth noting, there remain a significant number of persons infected who are asymptomatic or have minimal disease -some of whom have not been tested. Additionally there has been inconsistency in testing throughout regions. All of which add to the challenge of epidemiologic modeling,

As will be discussed later, further magnifying the enormous threat COVID-19 poses is the question of immunity -can it be acquired through surviving the infection, or via vaccine, and how sustained is the immune protection (13) ? And in the absence of specific COVID-19 antivirals, what are the best practices to date in the medical management of highly pathogenic coronaviruses?

While the questions seem to outnumber the answers, there are approaches that have had positive results clinically. With the rapidity of this pandemic, medical science has had a steep learning curve to scale, and research is still underway to answer the key questions we pose -immune response, protection, hyperimmune reaction, appropriate use of medications, non-medication interventions, appropriate preventive measures, vaccine development (14, 15) . These and other issues will be discussed in the COVID-19 Section of this edition of Disease A Month. To be sure there remain gaps in our knowledge, and in many cases we will provide the best science available as opposed to definitive answers which remain to be discovered; at the moment these still seem to be the guiding principles of medical management against COVID-19 for the foreseeable future.

What follows is an overview of coronaviruses in general, with a review of SARS and MERS, and lastly an in depth look at COVID-19.

The origin, transmission, and clinical therapies on coronavirus disease 2019 (COVID-19) outbreak -an update on the status

The biology of coronaviruses

Coronaviruses post SARS: update on replication and pathogenesis

SARS coronavirus: a new challenge for prevention and therapy

Middle East respiratory syndrome coronavirus (MERS -CoV) announcement of the Cornoavirus Study Group

Epidemiological, demographic, and clnical characteristics of 47 cases of Middle East respiratory syndrome coronavirus disease from Saudi Arabia: a descriptive study

The incubation period of Coronavirus Disease 2019 (COVID-19) from publicly reported confirmed cases: estimation and application

COVID-19 associated cardiovascular morbidity in older adults: a position paper from the Italian Society of Cardiovascular Researches

Novel coronavirus disease (COVID-19): a pandemic (epidemiology, pathogenesis, and potential therapeutics)

Clinical features of patients infected with 2019 novel coronavirus in Wuhan

World Health Organization COVID-19 Resource Center

COVID-19 coronavirus outbreak. www.worldometers.info/coronavirus

Immune response in COVID-19: addressing a pharmacological challenge by targeting pathways triggered by SARS-CoV-2

Triple combination of interferon beta-1b, lopinavirritonavir, and ribavirin in the treatment of patients admitted to hospital with COVID-19: an open label, randomized, phase 2 trial

Pharmacologic treatments for coronavirus disease 2019 (COVID-19); A review