Monday, June 01, 2020

Beijing now admits that coronavirus DIDN'T start in Wuhan's market... so where DID it come from?

China has become used to public confessions on television. But this time the words came from one of the nation’s top officials and had seismic global implications.

‘At first, we assumed the seafood market might have the virus, but now the market is more like a victim,’ said Gao Fu, director of the Centre for Disease Control and Prevention.

This was a stunning admission. For the same scientist had unequivocally pointed the finger of blame at Wuhan’s market where wild animals were sold when his country eventually told the world about a deadly new virus in the city.

The market was shut and cleaned up like a crime scene, in the words of another expert, as global attention focused on the ghastly trade in wild animals.

Gao’s initial analysis had made sense after previous outbreaks of zoonotic viruses (diseases that jump from animals to humans). Yet suspicion grew over the Chinese government’s failure to share data from animals sampled in the market following its early cover-ups.

Now Gao has admitted no viruses were detected in animal samples. He said they were found only in environmental samples, including sewage – before adding an intriguing aside that ‘the novel coronavirus had existed long before’.

No-one should doubt the significance of the statement since Gao is not just China’s top epidemiologist but also a member of the country’s top political advisory body.

Curiously, his revelation followed a television interview with Wang Yanyi, director of Wuhan Institute of Virology, in which she insisted that claims about the disease having leaked from her top-security unit were ‘pure fabrication’.

Gao’s sudden reversal came after a series of studies cast doubt on his original claim.

A landmark Lancet paper found only 27 of the first 41 confirmed cases were ‘exposed’ to the market – and only one of the four initial cases in the first two weeks of December.

Two weeks ago, The Mail on Sunday revealed another key academic paper by three America-based biologists that said all available data suggested the disease was taken into the market by someone already infected. So what does this all mean?

Sadly, the amount of massive research findings seems to be deepening rather than dispersing confusion over coronavirus, which is much more unpredictable than a simple respiratory virus in the way it attacks the body.

As Gao said in another interview, this is the seventh coronavirus to infect humans, yet none of its predecessors acted like this strange one. ‘The behaviour of this virus isn’t like a coronavirus,’ he said.

With regard to those three American biologists, they were ‘surprised’ to find the virus ‘already pre-adapted to human transmission’, contrasting its previously known stability with a coronavirus that evolved quickly during the global Sars epidemic between 2002 and 2004. Last week, I revealed that Australian scientists had similarly found Sars-CoV-2 – the new strain of coronavirus that causes disease – is ‘uniquely adapted to infect humans’.

Genetic stability makes it easier to find vaccines. But Nikolai Petrovsky, the vaccine researcher who headed the Australian team, said the virus was ‘not typical of a normal zoonotic infection’ since it suddenly appeared with ‘exceptional’ ability to enter humans from day one. He also highlighted the ‘furin cleavage site’, ‘which allows the spike protein to bind efficiently to cells in several human tissues, increasing infectivity, and does not exist in the most similar coronaviruses.

Some experts say this might have evolved through mutation during ‘unrecognised transmission in humans’ after crossing from an animal. Certainly it would help to find any intermediate host such as civets that ‘amplified’ the Sars virus from bats.

A paper by Professor Yong-Zhen Zhang, a prominent Chinese expert, said this was ‘arguably the most important’ difference between the new virus and its closest known relative, a virus called RaTG13 derived from a bat by Wuhan scientists.

Prof Zhang also noted the viruses closest to the new one were sampled from bats in Yunnan, 1,000 miles from Wuhan. Although 96 per cent genetically similar, ‘in reality this likely represents more than 20 years of sequence evolution’.

Last week, virology institute director Wang said scientists at her laboratory had isolated and obtained coronaviruses from bats but insisted they had only ‘three strains of live viruses’.

Her claim was dismissed as ‘demonstrably false’ by biosecurity expert Richard Ebright, professor of chemical biology at Rutgers University, New Jersey, who said the institute had published analyses of many more than three strains of live bat coronavirus.

Few doubt this freak virus came in lethal guise from an animal.  ‘Nature created this virus and has proven once again to be the most effective bio-terrorist,’ said Francis Collins, director of the US National Institutes of Health.

Yet this widely respected geneticist, appointed by Barack Obama, added significantly: ‘Whether [the coronavirus] could have been in some way isolated and studied in this laboratory in Wuhan, we have no way of knowing.’

Here lies the key point. It is foolish at this stage to rule out the possibility, however remote, that this pandemic might be the consequence of a Chinese laboratory leak.

As Professor Petrovsky said, scientists anywhere working with microscopic viruses can make mistakes and there are many examples to prove this point.

Above all, it is crucial to find the origins. If this pandemic is a natural event, it can erupt again from a similar source – and next time with even more explosive impact.

An example is ebola, another zoonotic disease (from fruit bats) that first appeared in 1976. All data indicated outbreaks led to fewer than 300 fatalities – until a subsequent outbreak in West Africa in 2014 led to 11,310 deaths.

Matters are complicated by Donald Trump’s finger-pointing at Beijing and the fact that a proven lab leak would be catastrophic for China’s President Xi Jinping as he tries to exploit the pandemic to push his dictatorial creed and nation’s global leadership.

Perhaps the best argument against the idea of the virus being lab-made came from Susan Weiss, professor of microbiology at Perelman School of Medicine, Pennsylvania.

‘There is no way anyone could design a virus that is this diabolical,’ she said succinctly.



ABC: No "second wave" in States That Started Re-Opening in Early May

This is excellent news in nearly every way, given that ABC News' data-based conclusion is drawn from information gathered over nearly four full weeks.  There may still be serious outbreaks, secondary waves, or changing trajectories that could require fresh mitigation efforts -- but so far, these are very positive developments for everyone except for those clinging to doomsday predictions about the impact of gradual state-level reopening strategies:

@ABC looked at 21 states that eased restrictions May 4 or earlier & found no major increase in hospitalizations, deaths or % of people testing positive in any of them. [SC, MT, GA, MS, SD, AR, CO, ID, IA, ND, OK, TN, TX, UT, WY, KS, FL, IN, MO, NE, OH]

Most, but not all, of those states are governed by Republicans, which almost certainly contributed to the tone and tenor of the news coverage of their strategies.  As the above tweet indicates, ABC examined not just a single metric (for instance, the misleading category of total cases, given increased testing), but an array of measuring sticks: Percentage of positive tests, hospitalizations, and deaths, the last of which is a lagging indicator.  Their verdict?  "No major increase[s]" in any of those categories, in any of the states mentioned, all of which started easing stay-at-home (or similar) restrictions on or before May 4th.  It is now nearly June. 

The dire proclamations, coupled with intensely negative coverage of GOP governors (Democratic leaders who presided over early re-opening processes strangely seemed immune to similar condemnations) must now be revisited.  Again, it's still premature to declare any semblance of victory over the disease for full vindication but some very important trends continue pointed in the correct direction:

Texas' senior Senator notes that as his state approaches 1 million COVID tests administered, infection rates continue to decline, despite a potential minor uptick in hospitalizations.  Relatedly, this interview with Dr. Gottlieb is worth reading. Among his points: "I think there will and should be an attempt to open schools in the fall. I don't think schools are going to remain closed until we get a vaccine."  Speaking of schools and the question of children as Coronavirus vectors, there's this new data point:

Sending children back to schools and day care centres in Denmark, the first country in Europe to do so, did not lead to an increase in coronavirus infections, according to official data, confirming similar findings from Finland on Thursday. As countries across Europe make plans to exit months of lockdown aimed at curbing the virus outbreak, some parents worry that opening schools first might put the health of their children in danger. Following a one-month lockdown, Denmark allowed children between two to 12 years back in day cares and schools on April 15. Based on five weeks’ worth of data, health authorities are now for the first time saying the move did not make the virus proliferate.

More than 100,000 Americans have died from this virus, a staggering percentage of whom contracted the disease in nursing home and long-term care facilities.  This is a humanitarian disaster, and the results have been, and will continue to be, deeply tragic.  Positive news and hopeful trends cannot erase these losses, but they can help shape our policy decisions moving forward, given the enormous public health and economic stakes. 



Did the lockdown save lives?

An economist's view

Whether school closings and stay-at-home orders slow an outbreak is an important and really challenging research question. This question must be answered before we compare economic costs and health benefits.

In March, states undertook dramatic and unprecedented measures to stem the spread of the SARS2-COV virus.  And yet COVID-19 has claimed 100,000 lives in the U.S.   Was the lockdown effective?  Economists frequently address such questions in our research.

Seeing the unseen, or the path that we did not choose, is the key here.  It is the fundamental challenge of economics, as illustrated by Frederic Bastiat’s parable of the broken window.  A shopkeeper must replace a broken window.  A neighbor, perhaps offering solace, points out that if windows never got broken, the town glazier would starve.  To avoid believing that broken windows boost the economy, we must recognize what the shopkeeper did not buy due to replacing the window.

Economists visualize the alternative paths we could choose.  What would have happened if we didn’t pass NAFTA, or hadn’t bailed out banks during the financial crisis, or if we raised the minimum wage to $15 per hour?  The term counterfactual refers to the unchosen path.

Economists devise principles for constructing counterfactuals.  Scenarios must be logically coherent and consistent with the available evidence.  We must avoid overly optimistic or pessimistic alternatives.

I have never estimated potential deaths in an outbreak of a disease but have researched tornado warnings and “worst case” tornadoes.  Like most economists, I recognize the challenges in evaluating the lockdown.

Here’s a first challenge.  WalletHub has scored the strictness of states’ COVID protection measures.  The average COVID fatality rate for the ten states with the strictest lockdown policies is 686 per million residents, versus a fatality rate of 68 for the ten least strict states, or one tenth as much.  The three highest fatality rate states are among the ten strictest states.

Does this show that lockdowns cause COVID-19 deaths?  No.  The states suffering the worst outbreaks will impose the strictest measures.  This is the endogeneity of policy problem.  Ignoring this issue would lead us to conclude that hospitals cause death because many people die there.  Controlling for policy endogeneity is a major research focus.

Another problem arises because states imposed policies and Americans realized that COVID-19 was a serious health threat at about the same time.  The NBA suspended its season March 11, people sharply reduced travel around March 15, and the first state stay-at-home order took effect March 19.  We have very few data points to tease out the effect of various policies from behavioral changes.

The United States was slow in rolling out testing for COVID-19, creating another challenge.  If we compared the number of COVID-19 cases in the month before and after lockdowns to test effectiveness, the total would rise simply because many more people were tested.  Can we detect a decline in infections during a period of expanding testing?

Even if March’s lockdown was effective, the policies may not be effective in another time or place.  Policy effects may not transfer for several reasons.  For the COVID lockdown, an important factor is peoples’ willingness to comply.  If Americans do not favor shutting down the economy for a second wave of the virus, stay-at-home orders may prove ineffective when reimplemented.

Researchers at Columbia University have evaluated the lockdown, based on computer simulations with travel data between cities and reported cases and deaths.  The policies appear to have stemmed the illness; indeed implementation of the same policies two weeks earlier could have avoided 83 percent of U.S. deaths through May 3.

The sophisticated technical analysis here, I think, obscures a bigger point.  “Nonpharmaceutical interventions,” as epidemiologists call such policies, do not prevent COVID-19 deaths.  Americans who did not get COVID this spring can still get sick next fall.  Only a vaccine or effective treatment will truly prevent deaths.

Whether school closings and stay-at-home orders slow an outbreak is an important and really challenging research question.  This question must be answered before we compare economic costs and health benefits.  Ultimately a lockdown is merely a delaying action.  Delaying actions are only worth fighting as part of a larger strategy.



For more blog postings from me, see  TONGUE-TIED, EDUCATION WATCH INTERNATIONAL, GREENIE WATCHPOLITICAL CORRECTNESS WATCH, AUSTRALIAN POLITICS, and Paralipomena (Occasionally updated), A Coral reef compendium and an IQ compendium. (Both updated as news items come in).  GUN WATCH is now mainly put together by Dean Weingarten. I also put up occasional updates on my Personal blog and each day I gather together my most substantial current writings on THE PSYCHOLOGIST.

Email me  here (Hotmail address). My Home Pages are here (Academic) or  here  (Personal).  My annual picture page is hereHome page supplement


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