Coronavirus – Credit CDC PHIL
# 6578
We are just three days into the emerging coronavirus story (see here, here, and here) , and the short message above, tweeted this morning by the World Health Organization, deserves repeating.
Despite coming from the same family of viruses as SARS (as do many other, far less pathogenic viruses), this new coronavirus is not SARS - and until more testing can be completed - we don’t know how much of a danger it actually presents.
The WHO continued to tweet:
Kidney failure, while not unheard of in SARS, was not a common presenting symptom back in 2002-2003. And SARS transmitted readily from human to human. Thus far, we haven’t seen signs of that sort of transmission with this new virus.
None of which is to say this virus couldn’t prove to be a bigger public health threat down the road, only that it is premature to think of this virus as the next global health crisis.
The media has been quick to refer to this virus as SARS-like, but it remains to be seen just how much the two viruses really have in common.
The discovery of new - even deadly - viruses that can afflict humans or other mammals is not uncommon. And most of the time, after an initial flurry of breathless news reports, the threat is found to be less than of pandemic proportion.
To provide a little perspective, a few viral discoveries in recent years that sparked initial hyperbolic headlines, but have (so far, anyway) failed to present a major public health threat:
- We’ve watched a number of triple-reassortant swine flu (Variant) viruses (H1N1v, H1N2v, H3N2v) make tentative jumps into human hosts (see An Increasingly Complex Flu Field), and so far they’ve failed to spread efficiently, or to produce substantial levels of morbidity.
- In August of this year (see New Phlebovirus Discovered In Missouri) the CDC announced the detection of a novel tick-borne virus in America’s heartland. Despite being detected in 2009, only two cases have been reported.
- In March of this year, we learned of a new H17 flu subtype, carried by bats in an unusual host: bats (see A New Flu Comes Up To Bat).
- In November of 2011 we saw a major die-off of seals in New England, that was eventually traced to a new mammalian adapted influenza virus mBio: A Mammalian Adapted H3N8 In Seals.
- In October of 2008 doctors in Zambia and South Africa ran across a mysterious, previously unclassified virus that caused hemorrhagic symptoms in its victims similar to Ebola (see Lujo Virus: Newly Identified Arenavirus) While highly contagious, and fatal in 4 of the 5 identified victims, it has not reappeared since 2008.
And if you want to go back a few more years, you can add Nipah, Hendra, H5N1, Ebola, Marburg . . . .
The truth is, scientists – with better tools available today – are indentifying `new’ viruses all of the time. A few well distributed viruses that until recently, were unknown, include:
- The human metapneumovirus (HMPV) was identified in Dutch children with bronchiolitis about a decade ago. Since then, it has been found to be ubiquitous around the world, and responsible for a significant percentage of childhood respiratory infections . . . yet until 2001, no one knew it existed.
- Human Bocavirus-infection (HBoV) wasn’t identified until 2005, when it was detected in 48 (9.1%) of 527 children with gastroenteritis in Spain (cite). It has since been found around the globe using PCR testing.
And the list grows longer every year.
While most will prove to be less than devastating in impact, we need only look at HIV, the 1918 H1N1 pandemic, and the pandemic viruses of 1957 and 1968 to realize that novel viruses can sometimes emerge and cause incredible morbidity and death.
According to well respected anthropologist and researcher George Armelagos of Emory University, we are entering the Third Epidemiological Transition.
This third transition began in the late 1970s or early 1980s, and is hallmarked by newly emerging infectious diseases, re-emerging diseases carried over from the 2nd transition (which began with the industrial revolution, and added chronic, non-infectious, degenerative diseases), and a rise in antimicrobial resistant pathogens.
When you combine those factors with an increasingly mobile global population of about 7 billion people, and huge increases in the number of animals being raised for food consumption (often in environments conducive to the spread of diseases), and you have a recipe for explosive growth in diseases.
Hence the need for continual surveillance, which will help us spot – and if we are lucky, even contain – the next pandemic before it can spread widely.
