A new virus has infected dozens of people in Wuhan City, China.
The virus was detected after more than 40 people were hospitalised with pneumonia in Wuhan City, China and the outbreak
traced to a large animal and seafood market. The Centers for Disease Control and Prevention reports
that person-to-person transmission of the virus appears limited.
Early this morning, the World Health Organization (WHO) reported
that an additional infection had been detected in Thailand in a person who is believed to have traveled from Wuhan
City. The WHO said, “it is essential that investigations continue in China to identify the source of this outbreak and
any animal reservoirs or intermediate hosts.”
The SMC asked experts to comment on the virus and outbreak.
Professor Michael Baker, Professor of Public Health, University of Otago, Wellington, comments:
, +64 21 355 056
“The present coronavirus outbreak in Wuhan City in China is certainly severe, with one fatality and six other people
reported to be severely ill with pneumonia out of about 40 confirmed cases. However, it does not appear to be highly
transmissible. Cases are largely confined to people who have had exposure to a live-animal market there. There has been
no confirmed person-to-person spread, including among several hundred known contacts. The new case identified in
Thailand had traveled from Wuhan and is still being investigated.
“With a newly emerging infectious disease that appears to be infecting humans for the first time, health authorities are
interested in three main features: severity of infection, ease of transmission, and controllability. Severity of
infection is measured in several ways, but the key feature is fatality risk. Transmissibility is summarised by the
reproduction number, which is the number of people typically infected by each case. If this number is much above one,
then we will see an exponential increase in cases. A very high number means an explosive epidemic. This is where
controllability comes in, which is the extent to which transmission can be prevented by easily available methods such as
contact tracing, isolation, quarantine, treatment, and vaccination (which is not usually available for newly emerging
“The SARS pandemic in 2002-03 illustrates these points. It was also a newly detected coronavirus transmitted from an
animal reservoir that infected humans. It caused severe respiratory illness with 8,098 reported cases
and a fatality risk approaching 10% (774 deaths, 9.6% fatality risk). It was highly infectious with a reproduction
number of 2-4 resulting in rapid spread to case contacts, particularly in hospital settings. In the end, it was found to
be highly controllable with simple measures, notably case detection, isolation and quarantine of contacts.
“The World Health Organization (WHO) has a major clearinghouse role in distributing information about emerging
infectious diseases such as this new coronavirus. Under international law (the International Health Regulations 2005)
all WHO member states are required to rapidly report potential emerging health threats such as this novel coronavirus,
particularly where they pose a risk of international spread, which is clearly the situation with this emerging viral
threat. The WHO is currently considering whether international measures are needed to control this outbreak. If that is
the case, then they could declare it a Public Health Emergency of International Concern. We are still several steps away
from that point.
“The US Centres for Disease Control and Prevention (CDC) also frequently becomes involved in investigating and reporting
on such outbreaks. Both WHO and CDC are providing regular updates on this current outbreak and its investigation.”
Declared conflict of interest: None.