Is the monkeypox epidemic peaking?
UK and Europe see signs of improvement, US trends less favorable
CDC published an update to their epidemic curve today. It’s tempting to see signs of plateauing, but the picture is not clear. For one thing, reporting delays and inconsistencies complicate interpretation. What is shown below is a mashup of dates that cases were diagnosed, reported via call center, or reported via data submission. Moreover, the total case count increased by 781 today which is not reflected on the graph below.
This messiness is normal, as different data streams yield different information. If you want the most up to date information, it’s best to combine them in order of quality. Use onset date if available, if not use diagnosis date, if not use report date.
There is an old joke that you can have data that is fast, cheap, or right—pick any two. It definitely applies to outbreak data. The true distribution of cases over time may reveal clearer trends. For now, I think it’s too early to say the US epidemic has peaked.
Regardless, the US does seem to be diverging from UK and Europe, where epidemic growth has clearly slowed. Interestingly, New York City is also trending down, putting it more in line with what we are seeing in Europe.
If I had to come up with a reason, I would guess that US cities and states that did not see many early cases are now becoming more heavily affected. Case counts grow as more cities “come online” even as some of the earlier-hit places begin to make progress. We saw this during the early days of the COVID-19 pandemic, when New York City suffered an early wave that subsided just as new hotspots began popping up around the country.
This should be easy to investigate, but alas, sub-national epidemic curves are hard to come by. Of the ten most affected states (including Washington DC), I could only find case counts over time for three. CDC also does not have it readily available, though it could be scraped from their website with daily diligence. That basic data would help to illuminate why the US is not seeing clear signs of improvement like our UK and European colleagues and reveal jurisdictions where additional intervention is needed.