Yes and Yes.
I’ve received lots of feedback the past few days when I’ve posted on new cases. Some are frustrated that we keep talking about cases instead of hospitalizations and deaths. I understand that frustration. With opening colleges/universities, we expected more cases among younger adults – and we are seeing that. In general, those cases are less severe than persons older than 50.
𝐁𝐮𝐭, 𝐰𝐡𝐲 𝐢𝐬 𝐢𝐭 𝐢𝐦𝐩𝐨𝐫𝐭𝐚𝐧𝐭 𝐭𝐨 𝐬𝐭𝐢𝐥𝐥 𝐥𝐨𝐨𝐤 𝐚𝐭 𝐜𝐚𝐬𝐞𝐬?
✅ Because it matters who the cases are (in terms of age, underlying health conditions, and social behaviors). Cases in younger folks are usually milder – which means they may think it’s just “allergies” and not self-isolate. This, in turn, could have a “spillover” into the surrounding community of at-risk individuals.
We, epidemiologists, are watching this data among younger folks and/or college towns very carefully. On one hand, the infections in younger people are less severe (and less likely to require hospitalization or death) – so, that’s a better thing than the same number of cases in persons over 50-60. However, if the spillover happens to at-risk individuals/communities, we will see increases in hospitalizations and deaths.
𝐒𝐨, 𝐭𝐡𝐞 𝐭𝐚𝐤𝐞 𝐡𝐨𝐦𝐞 𝐦𝐞𝐬𝐬𝐚𝐠𝐞 = New cases are our alert system to what could happen. Over the past 6 months, we have seen this clearly in the data. Cases typically precede hospitalizations by a few weeks.
𝐋𝐞𝐭 𝐦𝐞 𝐬𝐡𝐨𝐰 𝐲𝐨𝐮 𝐚𝐧 𝐞𝐱𝐚𝐦𝐩𝐥𝐞:
The picture shows 3 states. The red shows new cases per million and the blue shows hospitalizations per million. In all 3 states, new cases precede hospitalizations by 1-2 weeks (click on the source link below to see it yourself). Compare the peak of new cases in each state to the peak of hospitalizations in each state.
One size does not fit all when it comes to data metrics. Telling the full story of COVID-19 includes watching all data points – Positivity rates, cases, hospitalizations, deaths, proportional-to-population metrics, etc – and interpreting through the broad lens of public health and medicine.
-Friendly neighbor epidemiologist