by Patrick J. Byrne
PART ONE OF TWO PARTS (Read the second part here)
Covid19 (or SARS-CoV-2) is a new coronavirus related to the common cold that emerged from China in December 2019. It is a separate species of virus from the annual flu virus, or influenza.
The Lancet (March 30, 2020) reported an overall infection fatality rate of between approximately 0.4 and 1.4 and a case fatality rate of between 1 and 3 per cent, both with strong age gradients (the older a person, the more vulnerable they are to the disease). This is much higher than the mortality rate for the common cold or influenza.
The first response requires public intervention to protect the lives of vulnerable people, particularly the elderly and those with pre-existing conditions: for example, those with compromised respiratory systems, who are at particular risk from covid19.
Second, governments with health authorities have to ensure that hospital facilities can cope with the number of patients requiring care, particularly critical medical care that requires ventilators. This means managing the demand for care, using measures to restrict the spread of the disease, so that available critical-care resources are not overwhelmed by a high number of patients, as has happened in Wuhan, Italy, New York and Britain.
Managing caseloads in this way helps avoid situations where medical staff are forced to decide who will receive treatment, and who will not receive treatment and be left to succumb to the virus.
If hospitals are overwhelmed, then health protocols may require that the elderly with chronic diseases be given low priority; then the elderly, then others with various preexisting medical conditions.
If such harsh choices, beyond normal triage practices, are forced on medical staff, the risk is that this will reinforce a pro-euthanasia mentality. Emergency staff may be forced to take on practices different from those they were trained in for triage.
In order to protect the integrity of every patient, a balance of policies is needed to manage the demand for care so that hospitals are not overwhelmed by covid19 cases, while keeping as low as possible the cost of these policies on the community.
Third, keeping the number of covid19 cases low buys time for medical researchers to find and test anti-viral drugs, vaccines and treatments.
It is inevitable that we will face more, and possibly worse, pandemics in our modern world of intensive international travel and dense city living. If Australia’s heavy lockdown measures are found to be more than required, or fail to save as many lives as anticipated, this will be a test run for improving how pandemics are managed in the future.
While the current lockdown measures carry a heavy economic cost, there are major difficulties in setting acceptable policies when there are still so many unknowns at play: about the effectiveness of isolation and lockdown policies on contagion rates and death rates; about the strength of immunity for those who recover; and whether widespread infection and recovery will provide “herd immunity” for communities.
Then there are health-care limitations in terms of the availability of protective masks and clothing, disinfectants and medical equipment to treat a virus for which anti-viral drugs and treatments are still being developed and tested and for which there are no vaccines.
There are huge gaps in the science and crucial data needed for fine-tuning government policies.
Six months into this pandemic, there are not only many unknowns, there are many unknown unknowns.
HOW LETHAL IS COVID19?
As reported in The Atlantic (May 6, 2020), the threat from a virus varies according to its:
- Transmissibility – how easily it spreads.
- Virulence – ability to cause disease.
- Antigenicity – whether it is recognised by the immune system in some way.
- Resistance – how vulnerable it is to medications.
Some people have argued that, as the coronavirus has a low death rate, why the heavy government restrictions? Why not let the virus take its natural course in the community? The answer requires a consideration of both the contagion rate (that is, the reproduction rate as the disease is transmitted from one person to another to another) and the death rate (that is, the proportion of those infected who die).
On one hand, a disease like bird flu has a high death rate, but a low contagion rate, so infections can be contained and it causes few deaths. Equally, although a disease like measles has a high contagion rate across the population, it has a low death rate, so that there are comparatively few deaths, at least in developed countries. (See Diagram 1.)
On the other hand, a pandemic can result in a high number of deaths when a disease has a moderate contagion rate and moderate death rate.
The contagion rate
Covid19 spreads more easily than seasonal flu. The reproduction (contagion) rate is somewhere between 2 and 2.6. However, it varies between places and is influenced by the measures taken to slow transmission, like travel restrictions, social-distancing rules, quarantine and other health practices, as well as seasonal factors.
The Lancet (March 11, 2020) found that the median daily reproduction number in Wuhan declined from 2·35 one week before travel restrictions were introduced on January 23, 2020, to 1·05 a week later.
To understand how contagious is covid19, if it has a transmission rate of 2 and goes unchecked, then after five rounds of infections 32 people would be infected and after 10 rounds 1,024 would be infected. If covid19 has a transmission rate of 2.6 and goes unchecked, then after five rounds of infections 119 people would be infected and after 10 rounds 14,117 would be infected.
However, if covid19 is found to have a higher transmission rate of, say, 3 and goes unchecked, then after five rounds of infections 243 people would be infected and after 10 rounds 59,049 would be infected.
To contain a disease and stop it from spreading, it is necessary to reduce the contagion rate to below one.
The Lancet (March 11, 2020) also found that “once there are at least four independently introduced cases, there is a more than 50 per cent chance the infection will establish within that population”.
The death rate
The Lancet (March 30, 2020) said that, on preliminary estimates, the death rate, or case fatality rate (CFR) globally may be 1.38 per cent. However, it varies greatly from country to country.
Given that the world is still in the early stages of this disease, the Centre for Evidence Based Medicine (CEBM) (May 19, 2020) statistically estimated an eventual CFR rate of between 0.73 per cent and 9.18 per cent. In a chart covering about 100 countries, the CEBM found the CFR varied from 0.04 per cent in Qatar to 16.33 per cent in Belgium.
There are many reasons for the differences in CFR between countries. In Italy, which suffered a large number of deaths, many people greet with hugs and cheek kissing. On the other hand, Japan has a low death rate with only lightly imposed restrictions, but, as ABC News reported (May 23, 2020), in Japan wearing face masks is a common practice, typically people are meticulous about hygiene and wash hands regularly, most people don’t hug and kiss when greeting others, there is a low obesity rate (a contributing factor to the severity of covid19), and Japan has high-quality universal health care.
Order of magnitude of the covid19 pandemic
The New England Journal of Medicine (February 28, 2020) described the significance of the covid19 case fatality rate and contagion rate. It said that the data so far suggests that it is “many times more severe than typical seasonal influenza, putting it somewhere between the 1957 influenza pandemic (0.6 per cent) and the 1918 influenza [Spanish Flu] pandemic (2 per cent).
“That means covid19 will be much harder to contain than the Middle East respiratory syndrome (MERS) or severe acute respiratory syndrome (SARS), which were spread much less efficiently and only by symptomatic people.”
To put the covid19 infection transmission and death rates in perspective, it is possibly in the order of magnitude of the Spanish Flu.
Whereas the more deadly SARS and MERS were contained to a few countries and did not become global pandemics, the Spanish Flu was an uncontained global pandemic.
According to the US Center for Disease Control (March 20, 2019), the 1918-19 Spanish Flu is estimated to have:
- Infected 500 million people, about one-third of the world’s then population of 1,500 million people.
- Killed 50 million people (3.3 per cent of the global population), which represents 3.3 times the number who died in World War I and equivalent to 70 to 90 per cent of the estimated deaths in World War II.
In today’s terms, 3.3 per cent of the global population (of 7.8 billion) is 257 million people. While this illustrates the order of magnitude of what is being faced today, it is not a predictor of deaths from covid19.
HYDROXYCHLOROQUINE AS A TREATMENT
There has been considerable speculation about using anti-malaria drug hydroxychloroquine to treat covid19 sufferers.
After only six months of the disease, most research has involved only “observational studies”, not comprehensive scientific studies to test its effectiveness. This led to the warning that those studies were “limited by their low quality, often enrolling tiny groups of patients or lacking a control group to compare the results against”. (Business Insider, April 8, 2020)
The Lancet (May 22, 2020) published a study of about 21,000 patients with covid19 which found it provided no benefit, but the study was withdrawn after the authors later said they could “no longer vouch for the veracity of the primary data sources.” (The Lancet, 4 June, 2020)
Some clinical trials on the use of hydroxychloroquine subsequently resumed.
WILL RECOVERED PATIENTS HAVE IMMUNITY?
Given that the pandemic has only been under way for six months, it is unclear whether those who recover from covid19 will have long-term immunity. Covid19 is a close cousin of the severe acute respiratory syndrome virus (SARS) which came out of China in 2002-04. A 2007 follow-up study among 176 patients who had developed SARS found that SARS-specific antibodies were maintained for an average of two years, and significant reduction of immunoglobulin G–positive percentage and titers occurred in the third year. The study concluded that SARS patients might be susceptible to reinfection three years after their initial exposure. (Emerging Infectious Diseases, Volume 13, Number 10, October 2007)
On the other hand, the SARS virus disappeared. According to Marilyn J. Roossinck, Professor of Plant Pathology and Environmental Microbiology, Pennsylvania State University (The Conversation, 5 May, 2020), “many factors were involved in the end of SARS-CoV-1, perhaps including summer weather, and certainly strict quarantine of all those who had contact with infected individuals, but we don’t really know why the epidemic ended. Viruses are like that, unpredictable!”
WHY SO LONG FINDING VACCINES AND TREATMENTS?
To answer, ask a related question: although the world has known about the Ebola virus since 1976, why has little work been undertaken in finding a vaccine or cure until the recent 2014 outbreak in Africa?
At one level, it is not economical for pharmaceutical corporations to seek treatments and vaccines for some diseases. As a New York Times article (“Why Don’t We Have Vaccines Against Everything”, November 19, 2018) on viruses and vaccines explains: “It takes 10 years and more than $1 billion to develop a vaccine – a small fortune for a medical advance but a pittance for a weapons system.”
To recoup that money, a company has to sell more than $1 billion worth of the medication. When companies can’t recoup their investment in developing such a drug, they don’t undertake the research, testing and production. In other words, market forces won’t lead to the production of such drugs until a disease becomes widespread enough to make it economical to develop new drugs.
When markets fail (because it is not profitable to the private sector to invest in a cure), then it is up to governments and the international community to provide the research funds to find a cure. However, governments have been so reliant on unregulated free-market forces, they have failed to provide funds to find cures for diseases like Ebola, leaving it to the private sector.
Only now are governments around the world committing billions of dollars to boosting the research on this virus.