Coronavirus Cases Rise, But Hospitalizations Subside: What You Need To Know About COVID-19
Top Line: If you listen to some of the media pundits, you’d think that the coronavirus pandemic was worsening. While we’re not out of the woods yet, the situation has drastically improved since March and April. Even though infections are growing, hospitalizations are decreasing and we’re getting closer to a vaccine.
Looking At The Data
No doubt, the number of coronavirus cases and deaths are increasing. That’s a function of the spread of the virus, but also increased testing. Some have mocked President Trump’s remarks that the rise in cases is at least in part a reflection of more testing, but in reality it’s hard to disentangle the two patterns given all that’s going on.
One way to examine the role of testing is by estimating models that relate the number of positive cases with overall testing. Using data from the COVID-19 tracker at The Atlantic, I found that a 1% increase in overall testing is associated with a 1.23% rise in the number of positive cases from August to September, but only a 0.95% for the prior months. Although more work is required to make a definitive judgment, the diagnostic suggests that increased testing plays at least some role in accounting for the uptick of cases in recent months.
But, even setting aside the question of increased testing, the growth rate of cases and deaths has stabilized substantially since the height of the pandemic in March and April. For example, the median week-long growth in deaths between August and September is 4%, which is much smaller than the 15% growth rate between April and June.
Looking at infections and deaths is simplistic—they are extreme outcomes and deaths are likely a function of many other co-morbidities, especially among the elderly. In particular, we care just as much about the number of hospitalizations given that cases alone is not fully informative—someone can be infected, but have very light symptoms. Since data from Texas is quite detailed, let’s distinguish between cases and hospitalizations. Below, I plot the two patterns for the state of Texas, showing that hospitalizations are on the decline.
Are these patterns for Texas representative of the entire United States? Probably not entirely given that Texas is admittedly different from other states, but still the data is still informative. Using data from the COVID-19 tracker at The Atlantic, I can also compute the ratio of hospitalizations to positive test cases. The figure below shows that the ratio has been declining since June.
Although negative stories receive a lot of publicity in the media, there is actually a lot of reason to be optimistic about our recovery from the pandemic. In addition to the authorization for convalescent plasma, which helps create a bridge to the eventual dissemination of a vaccine, there is emerging evidence that a vaccine will be ready thanks to an accelerated timetable that’s been made possible through partnerships between major pharmaceutical companies and government.
Moreover, these pharmaceutical companies—mainly Pfizer PFE , Moderna, and AstraZeneca—are investing their own resources to produce the vaccine so that there is no appearance of politics playing a role. Admittedly, a vaccine is not a panacea, but it’s still an important step forward in the fight against the pandemic.
Why are perceptions about mortality risk so high in spite of the recent progress on the spread of the virus and a potential vaccine? Part of the reason has to do with salience, the uncertainty inherent in the whole situation, and the conflicting messages in the media. For example, recent research between Gallup and Franklin-Templeton points out that almost the entire age distribution is worried even though deaths are concentrated among those over the age of 65.
Lessons learned: There’s good news—even if it’s not always reported. By paying attention to all the data, not just the negative stories, you can obtain a more holistic perspective about the severity of the pandemic and the way out. Hospitalizations, especially relative to cases, are down and a new vaccine is entering the market to mitigate the transmission of the virus. Let’s press forward with realistic optimism about the future.