Decoding the data of the Chinese mpox outbreak
Sounds quite bad, right?
It turns out the reality is a tad more complicated. On the WHO website, the recent mpox data listed under China is the sum of cases reported in China, Taiwan, and Hong Kong.
The lack of data separation is significant here for a few reasons. First, while case counts have indeed risen in China, we don’t know by how much and over what time frame. China reported 106 cases in June alone, and it’s safe to assume there were additional cases in May and July. But there’s no information there to help us understand the exact urgency and severity of the outbreak, which can lead to panic and uninformed interventions. What’s more, as its handling of covid shows, the Chinese government may be holding onto data to serve its own interests.
Beyond that, this combined data reporting obscures the fact that Taiwan and China, with their different governing bodies, have responded to public health emergencies in very different ways.
While China has not signaled any interest in using mpox vaccines, Taiwan, which has its own CDC, has already administered over 72,000 shots so far. While China has only issued a one-month report of case counts, Taiwan has a public database showing how many new cases are reported each week, making it easy to see that the outbreak is on the decline there, six months after local transmission started.
So aggregating very different sources of data creates a confusing landscape and makes it hard to follow the impact of public health measures.
This means that when the WHO data shows a 550% increase in weekly new cases in China between July 10 and July 17, the jump means little. It doesn’t reveal the direction of the mpox outbreak; it only emphasizes the broken, irregular pattern of case reporting from China.
This is not to say the outbreak in China is insignificant, but that the data on the WHO website can easily mislead observers.