The facts
The 2019 novel coronavirus disease (COVID-19) pandemic started in
December 2019 in the city of Wuhan, Hubei province in China. It is a
highly contagious zoonosis (with a reproductive number of 2.8, which
means that under preexisting conditions one case generates 2.8 new
cases) produced by a beta coronavirus (SARS-CoV-2) that is spread
human-to-human largely by respiratory secretions and occasionally by
feces.1, 2 Over
a few weeks the disease spread to other Asian countries, to Europe, to
the Americas and finally across the world demonstrating a rapid doubling
time (6.4 days) and an asymptomatic but highly infectious
prodrome.2, 3 On
January 20, 2020 it was declared by the WHO to represent a public health
emergency. According to the Johns Hopkins Dashboard, as of March 20,
2020, 166 countries and 274,180 patients had been confirmed to be
infected, 11,375 have died and 87,991 have recovered. The infections
occurred predominantly (87%) in people of 30-79
years-old.4 Most
infections (81%) are asymptomatic or produce only mild symptoms,
whereas 15% occur in severe form that has required hospitalization.
Some 3-4% benefit from respiratory support in an intensive care unit
(ICU).4 The
death rate has been calculated between 0.39 - 4%, but this depends upon
patient age and is much higher in those older than 70
years.1, 4 The
most likely population to require mechanical ventilation are the elderly
and people with associated comorbidities (in particular cardiovascular
disease and hypertension, followed by diabetes mellitus) with a
predicted mortality of around
15-49%.4
Transmission is mainly produced by symptomatic patients, but it has been
reported that even asymptomatic individuals and those in the incubation
period (which can last longer than 14 days), can also be a source of
occult
transmission.4 Swab
PCR results for most asymptomatic patients turn negative in about 3
days, while symptomatic patients typically have detectable virus for
12-20
days. 3, 5 There
is still little information about the transmission during the recovering
phase.1
Most patients treated by head and neck surgeons have cancer, the direct
role of SARS-CoV-2 infection in their outcomes is unknown. To date,
there is no clear evidence that cancer patients have an increased risk
of infection or severe disease, beyond the immunosuppression caused by
the malignancy
itself.6 However,
cancer patients have experienced a higher risk of death due to the
limitations of access imposed by social distancing and the shortage of
operating rooms and ICU
beds.7