2019 Novel Coronavirus (2019-nCoV), Wuhan, China; Quarantine is Correct Response

The current state of knowledge is posted at (CDC) 2019 Novel Coronavirus (2019-nCoV), Wuhan, China.

The Washington Post, Wired, et al., question the quarantine of Wuhan. They cite multiple experts who say the measure cannot possibly stop the spread of the virus. That is true, yet the quarantine is still the right measure. The why is slightly subtle.

In a national disaster, emergency teams mobilize from unaffected areas. If the whole country were hit with disaster simultaneously, there would be no places to draw from. The Wuhan quarantine has a modest goal, to slow down propagation.

If 2019-nCoV, which is a virus, is a typical pathogen,

  • There are many more sub-clinical cases than overt diagnosed.
  • Those who recover will have at least temporary immunity.
  • When a certain fraction of the populace has acquired some immunity, herd immunity kicks in. When depends on the transmission efficiency of the virus.
  • When herd immunity manifests, new cases drop to a background level. This is thought to have occurred with West Nile virus. Mortality declines as well, as the most likely to die are the easiest to infect.
  • When this state of near-normalcy is approached, the Wuhan quarantine will be lifted. A pool of first responders with acquired immunity is now available to fan out from Wuhan to other hot spots.
  • For an untypical pathogen, look no further than Norwalk virus. We’re lucky it doesn’t kill; it breaks the mold for infectivity and acquired immunity, which does not happen. If Norwalk were less conspicuous and more lethal, transmitting via cough instead of vomit, we’d be in trouble.

This is the typical path to equilibrium. There are all kinds of worst cases. The mortality rate has been stated as 2.5%, concentrated among elderly and those with preexisting conditions. Now suppose 2019-nCoV is a really odd pathogen,  always causing overt symptoms, with 100% infection rate, infecting everyone in Wuhan, or elsewhere in China with clinical cases.

It implies that 2.5% of the Wuhan population die. One doesn’t like to think of such unlikely horrors, but it has to be considered by planners. It would amount to the almost simultaneous deaths of 35 million in China.

This has happened in the historical past. Before the discovery of germs and proper sanitation, cholera, typhus, and the Black Death decimated civilizations. The world outside of Africa has been spared Ebola,  a zoonosis that broke out from handling bush meat.  Human-to-human transmission in Africa is enhanced by social customs rare in other locales. But note, 2019-nCoV originates from the China version of bush meat.

For the Ebola response debacle, see Ebola, Rats, Lice, and History, and Hans Zinsser Part 1 and Part 2.

Part 2 critiques the phlegmatic approach of CDC/NIH to an Ebola vaccine. A handful of companies specialize in rapid vaccine development, direct from the genome. The system by which vaccines are approved is driven by safety. A vaccine that takes mere weeks to produce in small quantities engages an approval process of years. This is appropriate because most public-health vaccines are for widespread, non-emergency use.

Perhaps by tradition rooted in the 1976 swine flu fiasco, the cost of “no vaccine for 2019-nCoV ” is set for typical epidemiology. Yet the 1918 Spanish flu was untypically deadly for an airborne pathogen.

The timeline for use of an 2019-nCoV vaccine  has been quoted as a year or more. A lot of nursing homes could empty out in the course of another phlegmatic response. The cost/benefit analysis could have an unpleasant surprise.

It would be appropriate to:

  • Activate the existing national security protocols for rapid vaccine production.
  • Run the ferret preclinical tests, and Phase 1, ASAP.
  • For Phase 2 safety and immunogenic  trials, accept foreign results.
  • Begin large scale production before completion of Phase 3 trials of effectiveness, which may be abbreviated in  event of bad surprise.
  • If the cost/benefit ratio changes in the near future,  specialist companies can produce millions of doses per week.
  • Create multiple strategies to deal with antigenic shift.
  • This applies to antiviral drugs, should any be discovered.

If quarantines are instituted here, accept it with grace for the lives to be saved.

 

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