Key Question On
New Coronavirus Disease 2019 Is Whether Sustained Community Spread
Outside China Will Become Pandemic
[Editor’s Note:
This article is about an emerging and rapidly evolving public health
crisis. Case and death counts change daily. Readers interested in
learning the very latest information should consult the reliable
sources provided below.]
As of late February,
over 80,000 cases of the new coronavirus disease (COVID-19) and more
than 2,700 deaths globally have been reported to the World Health
Organization. Most of these
cases have been identified in
China, and the vast majority have occurred in a single
province (Hubei) where the first cases originated.
Early cases were
associated with a seafood and live animal market in the city of Wuhan.
However, the disease quickly spread person to person among individuals
with no connection to the animal market.
The virus
COVID-19 is caused by
SARS-CoV-2, a new betacoronavirus similar to MERS-CoV and SARS-CoV.
These latter two viruses are found in bats and suggest the new virus
has jumped the species barrier to humans from another intermediate
animal host, according to WHO. It could be a domestic food animal, a
wild animal, or a domesticated wild animal.
Extent of the
Epidemic
While the outbreak has
been centered in China, the disease has now been imported to at least
28 other countries. To date, the majority of cases outside of China
have occurred in connection with a single cruise ship, the Diamond
Princess, anchored in Japan and in the Republic of Korea. WHO
considers the risk to the region and to other countries in the world
to be "high".
The situation is being
watched very carefully by other countries for any evidence that the
virus is able spread and sustain transmission in any other open
population. This would mean that infected persons cannot tell where
and how they became infected.
Declarations
Some community spread
has occurred in Asian countries such as the Republic of Korea, Japan,
Singapore and Thailand.
WHO has declared a
public health emergency of international concern, and the US has
declared a public health emergency on January 31, 2020.
Pandemic?
As of this writing,
the criteria for declaring COVID-19 a pandemic have not been met,
although these criteria are not clearcut or universally agreed to.
Certainly, the occurrence of multiple outbreaks simultaneously in
numerous countries on different continents and involving large numbers
of persons will qualify as a pandemic
The major concern is
that COVID-19 could have transmission dynamics similar to influenza
which because of the widespread transmission produces a high number of
deaths even though the Case Fatality Ratio (CFR) is relatively low.
Control Strategies
If
sustained community spread occurs widely enough, countries will have
to abandon containment strategies focused on contact tracing and
quarantine and switch to mitigation interventions.
Right now many
countries outside of China are in containment mode doing contract
tracing but must be prepared to go into mitigation mode. The control
strategies at that point must change to include such measures as
social distancing which limits or restricts people’s ability to
congregate in public places such as sporting events, malls,
workplaces, and schools. Other interventions might include limiting
the use of public transportation and maintaining distance from others
(approximately 6 feet, according to CDC).
Useful Links For
Information About The COVID-19 Situation
A
visual guide to the outbreak from the BBC:
https://bbc.in/32jog5Y
A
Question and Answer document from the WHO:
http://bit.ly/37T7CuY
A
situation summary from the CDC:
http://bit.ly/39ZgWz3
Situation reports from WHO:
http://bit.ly/2HSCotG
|