Relevant New Information
Here’s a summary of relevant new information on COVID-19
- Hospital Capacity: A month ago, there looked to be a vast potential mismatch between hospital supply, ventilator supply and coronavirus patients. Now much of the hospital system in the country is idle and shutdown. Going forward, it is unlikely that there would be ventilator shortages in any part of the country even in a second wave of infections of Covid-19.
- Prevalence: There have been a number of studies this last week looking at the overall prevalence of coronavirus in the population varying from 14% in New York to 6% in Miami. It is not enough to create “herd immunity” but sufficient to reinforce our discussion a few weeks ago that most patients with coronavirus are asymptomatic.
- Treatment: Not a good week for treatment. Data on hydroxychloroquine from a VA study came back negative although there were issues with the timing of treatment and bias in the nontreated cohort. The WHO leaked data on Remdesivir that was negative and then withdrew the posting of the study. Cardiac complications from hydroxychloroquine are becoming noticeable in sick hospitalized patients making it less likely that it will be an effective in-patient treatment if started late.
- Transmission: Data keeps coming in that suggests that the major mode of transmission is indoors in crowded spaces. For example, eating outside in a restaurant looks like a potential option according to this study.
- Who is getting sick? By far the 2 segments of the populations that are getting sick are patients with a chronic condition (e.g., diabetes) and older adults. Because the prevalence rate is higher, the fatality rate of people who catch the virus is much lower (at this point likely less than 1%).
- When is the vaccine coming? No time soon. Best guess is 12 to 18 months, but there are scenarios where a vaccine is not created.
- Is this a local or national issue? The medical spread of the virus is absolutely a local issue. A look at the Hopkins map shows that the concentration of virus varies tremendously across the country county by county.
- How should I think about the number of deaths to date? Most of the deaths have been concentrated in the urban areas of New York and New Jersey with 54k deaths to date in the United States on April 26th. As a comparison, there were 69k deaths mainly in rural areas from the opioid epidemic in 2019 according to the CDC.
- Can we “contain” the virus? The big challenge is that there is a high amount of asymptomatic patients who are actively shedding the virus. This makes containment highly challenging for an entire population unless there is a country high sheltered from the rest of the world such as New Zealand. It may be possible to keep the virus away from a targeted set of people for a short period of time, such as NBA players in a playoff season – but only with multiple rounds of high volume testing and prevention.
- Are antibody tests for COVID-19 accurate? Not yet. If the prevalence of the disease is low and sensitivity and specificity is not high enough, then there will still be false negatives and false positives. I suspect that “version 2.0” of these tests will have high enough sensitivity and specificity but false negatives and positives will be an issue for the immediate time being.
- What are the goalposts of public health policy? A month ago, when social distancing started the public health goalposts were clearly defined “Avoid overwhelming hospitals and overwhelming ventilator capacity.” This made sense given our knowledge of the virus at the time, the situation in Italy, and that models were showing that many areas could have been overwhelmed.
The public health goalposts have morphed in some circles from “avoid overwhelming hospitals” to “avoid catching coronavirus”. If that is the target, this policy goal is not possible without prolonged social distancing lasting for months. Because if the strategy is initially successful it will need to continue until there is a vaccine.
If the goalpost is “protect vulnerable populations from infection” then a different targeted strategy around high-risk elderly patients and high-risk patients with chronic conditions may be in order. An immediate priority would be to protect patients in nursing homes and assisted living. The next priority would be to determine specific high-risk patients within the list of patients with chronic conditions that would allow a more precise targeting strategy.
Dr. Craig Tanio