The idea of applying a medical model, in which healthcare is customized based on a genetic understanding of the patient and their disease, is an ideal that may someday occur. We have had some success in the field of oncology, but we are not yet there with infectious diseases.
In the field of infectious disease identification, control and treatment — a field in which I have spent most of my career — we frequently have to apply more broad measures initially, and later narrow our focus once we have a better handle on the microbial “enemy.”
The obsession for the precise over the general, while rooted in good intentions, can sometimes slow or stymie the response to a pathogenic threat.
For example, when we select antibiotics for a patient dying of sepsis, we routinely reach for a “big gun” general antibiotic initially, based on the patient’s symptoms and medical history, so as not to miss a specific treatable bacteria. Once our laboratory tests give us a diagnosis, we then narrow the antibiotic choice to more directly target the offending pathogen.
We now face a new pandemic threat, the novel coronavirus first identified in Wuhan, China, (aka “2019-nCoV”), which has now spread to more than 20 countries. General containment measures — such as quarantine of individuals who are not sick, which has been a staple of infectious disease control for centuries — is being used.
When we have a better understanding of when and how long infected patients can spread this new disease, we can apply more precise measures of control that can be more effective.
The 2019-nCoV is killing people at a rate of about 2 percent, but this likely represents the tip of the iceberg and is fairly typical early in an outbreak. The most infirm and the elderly are the ones who are at greatest risk of death. There are likely many more mildly ill patients, who are not yet being counted.
Once we have a full understanding of the numbers of those individuals, we may find that the death rate is much lower. This cycle of understanding repeats itself with each new infectious disease.
There are many types of medicines being used in China, and some are being tested in research studies to try to find the “magic bullet” treatment to slow the killing. The World Health Organization is similarly concerned and conferring with experts to prioritize among different potential treatments. Admirably, as word spread about this ailment governments and vaccine manufacturers across the world have sprung into action.
The problem is, there is no such thing as fast and easy vaccine development. It takes time and precision. By the time we have an effective, fully tested vaccine, we frequently have moved on to the next infectious disease crisis.
The only reason we had vaccines to test during the 2014-16 and 2018-20 Ebola virus outbreaks in West Africa and the Democratic Republic of Congo is we had been studying vaccines against Ebola for four decades. We have known about 2019-nCoV for mere weeks.
At a time like this, we need to also consider more general approaches that could be useful, before we can determine the precise treatment measures. As we saw with Ebola, even providing basic supportive care could be life-saving. As many well-intentioned scientists try to unlock the secrets of 2019-nCoV, we need to step back and adopt a similar view — are there less precise medical activities that could make a difference?
While precision can certainly yield benefits, it is not necessarily the only path we should be following.
As people die, and the illness spreads, our search for that silver bullet should not be standing in the way of our taking a more general approach.
Until we find the “magic bullet,” there are several types of “shotgun” approaches that could be applied. One to consider is to ask recovered patients to donate plasma that could be used as a potential therapy for the most severely ill. This was one of the first measures that was attempted for Ebola and it has been used for decades with new infectious diseases.
Another potential option being considered includes using drugs that have been considered for the treatment of other coronaviruses that caused severe disease, such as the Severe Acute Respiratory Syndrome (SARS) or Middle East Respiratory Syndrome (MERS). Use of such countermeasures is, appropriately so, being considered within the framework of scientific studies. Otherwise we won’t really know what helps and what potentially causes harm.
Another innovative, general approach was developed by a California company, ExThera Medical Corporation. That approach is designed to filter out pathogens circulating in the bloodstream. It does not discriminate between pathogens, but filters them out based on receptors on the pathogen’s surface.
Whether it might work for coronaviruses is unknown, and may depend on how much of the disease severity is related to organisms in the bloodstream versus organisms in the lung.
There are likely other types of general approaches that could be useful. Certainly, gaining a better understanding from physicians in China regarding their observations, and what basic treatments, such as fluids, ventilator management, etc., appear beneficial or harmful is key, because it may take some time for the “magic bullets” to catch up.
The patients deserve that, whether they are in Wuhan, Singapore or Chicago.
