Tuesday, June 2

China's handling of swine flu bursts CDC's bubble

Watch carefully, don't blink:

May 09
Australia reports their first confirmed case of swine flu; an infected American airline passenger traveling from the USA. Queensland, Australia's chief health officer Dr Jeannette Young said more cases were likely in the future "because we have a lot of planes coming into the country every day''.

June 01
Australia's confirmed swine flu cases: 401.

The cases are doubling about every two days.

May 10
Mainland China reports their first confirmed case of swine flu, an infected Chinese citizen traveling on a flight from the USA via Tokyo.

June 01
Mainland China's confirmed swine flu cases: 38.

It should go without saying that Mainland China also has a lot of flights coming into the country each day. Yet even with adding Hong Kong's 23 June 1 confirmed cases (which are also stupendously low) to bring the grand total in China to 61, and even accounting for unreported/unprocessed cases in all of China, the difference between the Australia and Mainland China tallies is staggering.

What explains the difference? In one sentence: Mainland China's decision to quarantine every passenger with a fever arriving at their ports of entry.

The draconian approach to battling swine flu has been controversial -- particularly with Mexico's government. But even before the June 1 numbers came out public health officials were acknowledging that the approach was greatly slowing the rate of swine flu infections. March 28, The Washington Post:
[...] While the spread of swine flu seems to have slowed for the time being, and other countries have relaxed previous restrictions on public gatherings and travel, China has become increasingly vigilant -- throwing several thousand foreigners and Chinese nationals into quarantine facilities for having little more than a cough, runny nose or slight temperature and having been in contact with someone with a suspected case of swine flu.

Some public health experts say its aggressive measures to deal with a possible pandemic -- devised after China's slow and secretive response to the deadly SARS virus in 2003 was blamed for spreading the respiratory disease -- should serve as a model for other countries.

Statistically speaking, China's efforts have been an amazing success this time around. Of a total of 13,400 confirmed infections worldwide, only 14 have been in China, though nearly a fifth of the world's population lives within its borders.

From a public relations standpoint, however, China's medical checks and quarantine procedures have been a disaster. [...]
That last sentence is not strictly accurate. How you see China's actions depends on whether you're living in a rich country, whether you have easy access to Tamiflu and Relenza and great medical facilities, and whether you know your government is so rich and powerful it can snap up a big share of swine flu vaccine if/when it becomes available. The more you move away from that profile, the less of a PR disaster China's actions seem.

The numbers quoted in the Washington Post report are of course behind the June 1 data curve but the low number of confirmed cases has continued to hold. That means the contrast between the Australia and China tally is the worst indictment to date of the CDC's recommended approach to dealing with an infectious disease outbreak.

The CDC approach, which was aped by WHO, was to refuse to recommend quarantine and other aggressive NPI (non-pharmacological intervention) measures such as suspending airline flights; this on the misleading argument that once a highly infectious virus has arrived in a country such measures cannot stop the virus.

As I have pointed out many times on this blog, once such a virus is loose "stopping" it is not the issue; what's critical at that point is to slow the rate of infection -- a point that has been made even by the biomedical mathematicians who advise the CDC.

China's Ministry of Health, and Hong Kong's redoubtable Dr Chow, grasped that simple point, and the procedures they implemented have by now amply demonstrated that they've managed to greatly slow the rate of swine flu infections in their regions of China.

Yet that simple point continues to elude the CDC, and all the U.S. officials they're advising at the White House and across an alphabet soup of federal agencies: Health and Human Services, Homeland Security, State, Transportation. Not to mention the U.S. state and city health officials the CDC is advising.

Why are all these people having such a hard time confronting a simple point?

If you reply that the CDC probably thinks it's not necessary to take the most aggressive NPI measures because the disease isn't all that lethal -- that's mixing up two completely different subjects, and dangerously so. Here's why:

First I'll review quotes I posted on May 11. (See the post for links to the sources.)

On April 27 Janet Napolitano told a reporter: "You would close the border if you thought you could contain the spread of disease, but the disease already is in a number of states within the United States."

Mr Obama echoed her statement. When asked at his April 29 press conference whether he was considering shutting the border with Mexico, he replied:

"I've consulted with our public health officials extensively on a day-to-day basis, in some cases, an hour-to-hour basis. At this point they have not recommended a border closing. From their perspective it would be akin to closing the barn door after the horses are out, because we already have cases here in the United States."

As I stressed in the May 11 post, Obama and Napolitano were simply summarizing the thinking at the CDC, which does not address the lethality of a highly infectious disease. The thinking addresses their idea, based on their reading of mathematical models, of how such a disease spreads once it arrives in a country.

From their reading, there is no way to stop any highly infectious disease from spreading to virtually all vulnerable people in the country -- if there is not an effective vaccine administered to virtually the entire population (a virtual impossibility).

Ergo, there's no use taking the kind of NPI measures that China is deploying; e.g., blocking flights from a country with a high rate of infection, quarantines, taking the temperature of passengers on international flights even before they leave the plane, using thermal imaging machines at airports and ports to monitor disembarked passengers' temperatures, making constant public service announcements to warn of the disease, urging people who don't feel well to wear surgical masks, etc.

But then China had the bad form to burst the CDC's bubble by demonstrating that aggressive NPI measures greatly slow the infection rate for a highly infectious disease.

If you say, 'Back up; are you telling me that the CDC would keep relying on the same mathematical models even if the disease was a superkiller?'

Well, they're relying on their reading of the models. But by their own reasoning -- the answer is yes.

If you reply, 'That doesn't sound right' -- Welcome! Welcome to the party! Take off your hat and coat and stay awhile. Why do you think I've been yelling myself hoarse on this blog for the past month?

I hate to break this news to you all at once but there are lunatics in charge of America's federal infectious disease control agency. Dangerous lunatics.

How dangerous? That would depend on which country you're in, now wouldn't it?

The first confirmed case of swine flu in Hong Kong was also the first confirmed case in all of Asia. That was on May 2 -- five days after Homeland Secretary Napolitano passed along the CDC's pearls of wisdom.

The first confirmed case of swine flu in the United States came on April 14 -- 16 days I repeat 16 before President Obama explained that from the CDC's perspective, aggressive measures to limit the entrance of infected Mexicans to the USA "...would be akin to closing the barn door after the horses are out, because we already have cases here in the United States." (1)

But the barn door wasn't open at that time in Asia, was it? It wasn't open in many countries, including Australia.

The first clear sign, the first "tell" that something really strange was going on in Mexico, came on March 18 -- I repeat March -- when biosurveillance picked up an unusual "influenza-like" disease outbreak in Mexico City. The outbreak was initially assumed by Mexican health officials to be "late-season flu" outbreak and not a new virus strain. (1)

On what grounds did the Mexican officials make that daffy assumption? On the same grounds that U.S. health officials failed to send out alerts to every country on April 14: on the grounds that their protocols were perfectly in synch with their calendar year: 1952.

So the CDC influenza officials are not the only lunatics in public health. Only a handful of national governments took anything approaching rational action in the face of the swine flu outbreak.

Why only a handful? Because just as the world was completely unready for the kind of asymmetrical warfare al Qaeda demonstrated in 2001, so the world was unready for the blitzkrieg of the 2009 swine flu virus -- and for the same reason: their defense systems were a quarter century out of date. And so were their mathematical models.

The CDC is thinking only in inbound terms, not outbound terms, when they say that once a disease is in a country there's nothing that can be done to stop its spread -- at least not without vaccinating the entire population. For the sake of argument we'll accept that thinking. But once a disease is in say, the USA, that doesn't mean it has to proceed from the USA to every country that doesn't have the disease.

That seems to be one limitation of the models that the CDC references; the models pertain to the spread of an infectious disease in the USA, not globally.

That was Dr York Chow's point when he said, "I think that everyone has the responsibility to ensure that they do not allow any infection to go outside their country or territory."

If you say he's asking for the impossible in today's highly interconnected, globalized world of commerce -- no, he's asking for public health officials and citizens to bring their thinking into the modern globalized era, before a catastrophe happens.

Realize that China's approach to managing swine flu is directed as much at outbound plane passengers as inbound ones. The public health officials on the Mainland and in Hong Kong are knocking themselves to stop the disease from leaving their airports. Are they completely successful? No. Are their actions helping to slow the rate of infection in other countries? Yes.

And note their strategy does not include blockade. China hasn't pulled up the drawbridge; they're trying to work out a balance between the demands of a highly globalized era and protecting populations from the devastation of a highly lethal infectious disease.

And this is one of those situations where we don't dare say, 'We'll cross that bridge when we come to it.' That's because the road to the bridge will be impassable with dead bodies, if we wait until after a superkiller pandemic gets underway before we start retooling public health measures for the modern era.

Retooling will involve wrestling with questions about civil liberties. A reader asked how I'd feel if I found myself led away in handcuffs from an airport to a quarantine area.

Three days in quarantine, huh? Three days all to myself, no ringing phones, no CNN and Fox news, no poring over the ramblings of CDC and WHO officials; three days being waited on hand and foot. Well, dispense with the handcuffs because I think I could take one for Team Humanity.

But the reader has a serious point that must be addressed. There are many other points that need addressing. We need to hunker down to those issues fast. This is because the CDC's skill at verbally palming an ace from the bottom of the deck is on full display with their discussion of the swine flu's lethality.

They've said that the virus doesn't have the "virulence markers" of the 1918 flu virus. I can't read a genome sequence so I'll take their word for it. But notice they didn't say that the swine flu virus has no markers that would indicate a proclivity for extreme virulence.

Not that I like ending on a cliffhanger note but I see it's almost 3 PM and I'd announced I'd get this post out this morning. I'll pick up the discussion tomorrow.

1) Wikipedia 2009 Swine Flu Outobreak


CGardner said...

CDC has made the decision not to treat H1N1 much more seriously than seasonal influenza.

From the May 28th CDC press briefing transcript:

"I want to let you know that beginning next week, we're going to shift to a different schedule. We'll be updating our case count information less frequently. And every Friday we'll be doing updates of what we call FluView, a more extensive report on many ways that we track influenza. Weekly reporting through FluView is what we do during the annual influenza season, including the peak of the season. And we hope that sharing information on that basis will keep people informed."

Dr. Anne Schuchat, Interim Deputy Director for Science and Public Health Program

Pundita said...

CG: Thanks for the update. So. We're learning that CDC officials are also master magicians. In the Book of CDC Spells under the heading, "How to make a pandemic vanish," it says:

"Strive for very incomplete data collection so there's no way for a pandemic to exist.' Oh and make sure to say, 'Presto!' when you wave your wand, so you don't turn yourself into a toad."

DocJim said...

This is one of those things about math that bureaucrats know and others often forget. Math depends on assumptions and changing the definitions/assumptions will immediately change the numbers.

The CDC magicians are allowed by law/regulation to make numbers change by changing the definitions.

"Immediately change" sounds a lot like "Presto."