- NUMBER OF HOSPITALIZED CORONAVIRUS PATIENTS IN SANTA CLARA COUNTY CALIFORNIA - 4 Apr 2020
- CORONAVIRUS AND THE SOFA SCORE - 31 Mar 2020
- CAN ANESTHESIA MACHINES BE USED FOR ICU VENTILATORS? - 23 Mar 2020
Dr. John Ioannidis, professor of medicine, epidemiology and population health, biomedical data science, and statistics at Stanford University, and co-director of Stanford’s Meta-Research Innovation Center, wrote a controversial piece entitled
It’s worth reading and is sure to spark discussion. His central thesis is that without reliable mass testing we have no idea how many coronavirus cases there are. That is, we do not know the denominator of the equation:
Coronavirus deaths / Total coronavirus cases = mortality rate
If the denominator is vast (due to asymptomatic carriers) the mortality rate could be markedly lower than estimates. Ioannidis writes:
“The data collected so far on how many people are infected and how the epidemic is evolving are utterly unreliable. Given the limited testing to date, some deaths and probably the vast majority of infections due to SARS-CoV-2 are being missed . . . Reported case fatality rates, like the official 3.4% rate from the World Health Organization, cause horror — and are meaningless.”
He expands on the data from the cruise ship Diamond Princess:
“Projecting the Diamond Princess mortality rate onto the age structure of the U.S. population, the death rate among people infected with Covid-19 would be 0.125%. But since this estimate is based on extremely thin data — there were just seven deaths among the 700 infected passengers and crew — the real death rate could stretch from five times lower (0.025%) to five times higher (0.625%).”
“If we assume that case fatality rate among individuals infected by SARS-CoV-2 is 0.3% in the general population — a mid-range guess from my Diamond Princess analysis — and that 1% of the U.S. population gets infected (about 3.3 million people), this would translate to about 10,000 deaths. This sounds like a huge number, but it is buried within the noise of the estimate of deaths from “influenza-like illness.” If we had not known about a new virus out there, and had not checked individuals with PCR tests, the number of total deaths due to “influenza-like illness” would not seem unusual this year.”
Dr. Ioannidis uses the metaphor of an elephant (the economy) and a house cat (the virus) to make his point:
“A population-wide case fatality rate of 0.05% is lower than seasonal influenza. If that is the true rate, locking down the world with potentially tremendous social and financial consequences may be totally irrational. It’s like an elephant being attacked by a house cat. Frustrated and trying to avoid the cat, the elephant accidentally jumps off a cliff and dies.”
Ioannidis goes on to say:
“we don’t know how long social distancing measures and lockdowns can be maintained without major consequences to the economy, society, and mental health. Unpredictable evolutions may ensue, including financial crisis, unrest, civil strife, war, and a meltdown of the social fabric.”
“with lockdowns of months, if not years, life largely stops, short-term and long-term consequences are entirely unknown, and billions, not just millions, of lives may be eventually at stake.”
“If we decide to jump off the cliff, we need some data to inform us about the rationale of such an action and the chances of landing somewhere safe.”
Marc Lipsitch PhD, professor of epidemiology at the Harvard T.H. Chan School of Public Health and director of Harvard’s Center for Communicable Disease Dynamics wrote a column in response to Dr. Ioannidis. The column is entitled
Quotes from Dr. Lipsitch’s column include:
“. . . two things are clear. First, the number of severe cases — the product of these two unknowns — becomes fearsome in country after country if the infection is allowed to spread.”
“Second, if we don’t apply control measures, the number of cases will keep going up exponentially beyond the already fearsome numbers we have seen.”
“It is crucial to emphasize that a pandemic like this does not dissipate on its own, as Ioannidis suggested as a possibility.”
“There are two options for Covid-19 at the moment: long-term social distancing or overwhelmed health care systems. That is the depressing conclusion many epidemiologists have been emphasizing for weeks”
“Ioannidis is right that the prospect of intense social distancing for months or years is one that can hardly be imagined, let alone enacted. The alternative of letting the infection spread uncontrolled is equally unimaginable. We certainly need more data.”
“Waiting and hoping for a miracle as health systems are overrun by Covid-19 is not an option. For the short term there is no choice but to use the time we are buying with social distancing to mobilize a massive political, economic, and societal effort to find new ways to cope with this virus.”
As an internal medicine and anesthesia physician, my assessment is that the two greatest short term medical needs right now are:
- More data, i.e. a test for coronavirus – a test that is easily available, easily manufactured, and accurate. This will enable us to quantitate the denominator of the equation above, and to diagnose who is coronavirus-free, and thus able to return to the workforce.
2. Adequate supplies of personal protective equipment (PPE) and ventilators for healthcare workers to care for COVID-19 infected patients.
With heroic efforts from the private sector and the government, these needs seem attainable in the short term. Supplies of tests, PPEs, and ventilators can make significant changes to the spread of the pandemic. We face dual threats at this time: the coronavirus pandemic and the economic shutdown.
If months of ongoing social distancing are required, let’s hope Dr. Ioannidis’s warning of the elephant jumping off the cliff does not occur.