Even More Draconian Quarantines Are Needed to Stop Coronavirus 2019 Ncov

The Emergency Committee of the World Health Organization reports that China currently premlimary calculation of human-to-human transmission (R0) of coronavirus 2019 ncov is 1.4-2.5.

HKU Medicine has released new nowcasting and forecasting estimates for the 2019-nCoV outbreak. They estimate that the current R0 is between 1.9 and 2.3, and that current case counts may be in the range of 20,000 to 78,000.

Even with the lower transmission rate, there need to be draconian quarantine efforts. We are at the point where China has to use all community-level measures to increase social distance and more community-wide quarantines.

R0 transmission must be reduced to less than 1.0 to stop the spread of the disease.

There is other UK and US research which estimates the basic reproduction number of the infection (𝑅0) to be between 3.6 and 4.0. Novel coronavirus 2019-nCoV: early estimation of epidemiological parameters and epidemic predictions
Jonathan M. Read, Jessica R.E. Bridgen, Derek A.T. Cummings, Antonia Ho
, Chris P. Jewell.

If the R0 is 3.6 to 4.0 then 72-75% of transmissions must be prevented by control measures for infections to stop increasing.

The spreading rate is between the flu and SARS.

They estimate that only 5.1% of infections in Wuhan are identified, indicating a large number of infections in the community, and also reflecting the difficulty in detecting cases of this new disease. Surveillance for this novel pathogen has been launched very quickly by public health authorities in China, allowing for rapid assessment of the speed of increase of cases in Wuhan and other areas.

If no change in control or transmission happens, then we expect further outbreaks to occur in other Chinese cities, and that infections will continue to be exported to international destinations at an increasing rate. The model suggests that by 4 February 2020 the number of infected people in Wuhan will be greater than 190
thousand (prediction interval, 132,751 to 273,649). They predict the cities with the largest outbreaks elsewhere in China to be Shanghai, Beijing, Guangzhou, Chongqing and Chengdu. We also predict that by 4 Feb 2020, the countries or special administrative regions at greatest risk of importing infections through air travel
are Thailand, Japan, Taiwan, Hong Kong, and South Korea.

If the official number of cases is below 10,000 in eight days then the R0 estimate of 3.6 to 4.0 would be higher than the actual situation. However, higher cases would not confirm a higher transmission rate. The percentage of identified cases could increase from 5%.

The UK-US model suggests that travel restrictions from and to Wuhan city are unlikely to be effective in halting transmission across China; with a 99% effective reduction in travel, the size of the epidemic outside of Wuhan may only be reduced by 24.9% on 4 February.

Reducing the spread by 25% is still useful.

So far the deaths from coronavirus is mostly older men with previous health issues. The youngest person to die in the first 17 was a 48-year-old woman. As of today’s morning report there are now 82 deaths.

Beijing has broadened the extraordinary quarantine to more than 50 million people, but the mayor of Wuhan, the outbreak’s epicenter, said 5 million people had already left his city.

Wuhan’s mayor admitted that the city did not release information about the virus in a timely manner but hinted that it was prevented from doing so by central authorities.

A scientific assessment of the spread of the disease, assuming an optimistic 90 percent quarantine, still predicted more than 59,000 infections and 1,500 deaths — twice the toll of the 2002-2003 SARS outbreak.

A John’s Hopkins simulation led by Eric Toner published 3 months ago indicates that an uncontained pandemic disease over a span of 18 months would have deaths in the range of 65 million. A global pandemic could cause an average annual economic loss of 0.7% of global GDP — or $570 billion. They indicated that their model was not matched up to this actual disease outbreak.

The Bill and Melinda Gates Foundation announced $10M in awards to fight the epidemic. Half is to go to China and half to Africa. Reuters has reported that the Chinese government is dedicating almost US$9 billion toward efforts to quell the spread of the outbreak. However, News China has reported totals closer to US$1.5 billion.

The World Health Organization has not declared a Public Health Emergency of International Concern (PHEIC). A PHEIC is a formal declaration by the World Health Organization of “an extraordinary event which is determined to constitute a public health risk”.

Amplification has occurred in one health care facility. Of confirmed cases, 25% are reported to be severe. The source is still unknown (most likely an animal reservoir) and the extent of human-to-human transmission is still not clear.

27 thoughts on “Even More Draconian Quarantines Are Needed to Stop Coronavirus 2019 Ncov”

  1. I’m sure that right now people are very carefully counting.

    At this point all the senior leaders will be screaming for information to try to work out what’s going on. THEY want the real numbers.

    My point is that you can’t count someone who is quietly at home, going through a box of paracetamol/day and sniffling their way through the thousands of wechat memes that have sprung up about the crisis.

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  2. You are probably correct, and completely missing the point.

    .. Chinese air and water pollution can’t get on a plane, travel to New York, or London, or Lagos, or Delhi and start killing people there.

    .. Chinese air and water pollution is limited to current amounts. We won’t suddenly have it grow 10 times worse over a week and surprise us.

    .. Air and water pollution is known and understood. If you are middle-upper class and you eat imported food, drink purified water and live and work in filtered, air conditioned environments then you are fairly protected. Now all of a sudden they are not and it’s freaking them out. (The fact that they need all that protection means that “impurities can kill you” is a constant background threat that affects their daily thinking and so this just sets off all that built up worry.)

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  3. Yeah, this.

    If you were in China and you got sick, and you were fairly sure (correctly) that going to hospital would see you mandatorily confined to a ward filled with people, some of whom definitely have the disease… then unless you were feeling like death you’d probably hole up in bed with a load of over-the-counter drugs and tough it out.

    So anyone with a mild case will probably not (ever) appear on the official statistics.

    But if you die? You are not going to be able to hide that. There may be some dead people locked in their one room apartments who won’t be found for a few days, but generally speaking the government knows the death toll fairly accurately.

    Hence the government calculation of the death rate is probably higher than reality, rather than lower. On the other hand government calculation of the number of cases would be lower than reality.

    Then we are left to wonder, does the Chinese government give us the numbers they’ve actually measured, do they adjust the numbers for the above considerations, do they adjust them correctly, and do they tell us what they think are the real numbers or what numbers they think would be best for political reasons?

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  4. “If anyone knows of the term for the ‘asymptomatic period of infectiousness'”

    Maybe we can coin our own word for it. How about lovely? The lovely period.

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  5. More important than how much larger than 1 R0 is, for quarantine measures, is (Incubation-Latency) period.

    If anyone knows of the term for that difference (other than “asymptomatic period of infectiousness”) I’d really like to know what it is. The lack of a word for that period is probably contributing to bureaucratic inertia world-wide since bureaucrats have trouble managing what they can’t measure anyway, and if they don’t even know they’re supposed to be managing something because there’s no _term_ for it, they’ll just manage something else.

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  6. Fatality rates being reported are based on numbers like 2700 confirmed cases with 106 deaths.

    Thats not actual because while the number of people who’ve gotten it but not confirmed are higher (by like 20x) the number of people who have died of coronavirus and been misdiagnosed is probably close to zero.

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  7. For comparison:

    In the USA about 40 million people get the flu a year and 14,000 die. So about a 1 in 2857 chance of dying.

    This seems to have killed about 100 for 54,000 cases. So 1 in 540 chance of dying.

    EDIT: The most at-risk of dying population is the infirm old or infants with underdeveloped immune systems for both influenza and coronavirus.

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  8. It seems that Chinese authorities initially downplayed the contagiousness
    of this, and probably the number of cases also. We can infer from the
    measures adopted that close contact is not necessary. This looks more
    Dangerous than SARS, albeit somewhat less (expecially regarding the mortality rate) than the Spanish flu.

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  9. I am reading your post having just come from the market, after buying rice, biscuits,
    canned sardines, beans, Tabasco sauce, and grappa. A situation where there’s
    nothing to lose at being prudent.

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  10. I’m no expert, but I remember SARS and I still don’t see this getting as out of control as people fear it might. That’s not saying fear isn’t healthy, and it’s always good to keep sustenance in stock in case things really hit the fan.

    But, I’m seeing some hype over it getting out of control, people saying. “It’s gonna be like that movie Contagion!”

    That said, the increased incubation time does make it harder to pin down. So that’s creepy.

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  11. Good advice. I’ve got to do the same. Next weeks could become a replication of the SARS scare, only worse given this one is more contagious (airborne, asymptomatic, people to people. That’s scary).

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  12. Hm, I should probably review my stock of non-perishable foods, to make sure my family is set to hole up if things get bad.

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