Three Mpox Challenges

Since May 2022, countries around the world have been dealing with the first mpox outbreak to spread broadly beyond Africa. By November, there were nearly 80,000 confirmed cases in more than 100 countries (1).

But those numbers actually belie the tremendous challenges we have experienced in detecting mpox in this outbreak. For most of 2022, testing has been a significant bottleneck in addressing this public health threat. In New York City, for example, which has a population of nearly 8.5 million and quickly became the epicenter of the outbreak in the US, testing was so constrained that, until July 2022, only 10 people could be tested each day (2).

The US Food & Drug Administration’s ability to grant emergency use authorization for new mpox tests – a development that occurred in September 2022 – should help alleviate testing issues in the coming months. Still, the clinical laboratory community has a number of hurdles to clear before it can roll out accessible, reliable testing for mpox. Many of these challenges can be addressed with better collaboration between industry and clinical labs.

Mpox-specific sequences and testing protocols
 

So far, the sequences and testing protocols approved for mpox testing are not actually mpox-specific — they are for the broader category of non-variola Orthopoxvirus DNA viruses (3, 4). It is acceptable to use this now because mpox is the only widely circulating member of this group – but ultimately labs will need methods that are specific to mpox. This challenge is likely to be addressed as test manufacturers bring new assays to the FDA for emergency use authorization.

Early access to reliable controls and reference materials
 

One key message we learned from COVID-19 is that companies need to do more to get reliable testing materials into the hands of test developers – both for clinical labs and for commercial test manufacturers. The severe testing constraints that occurred in the first few months of the mpox outbreak were largely caused by limited access to controls and reference materials needed to build, verify, and routinely run new assays. Since then, we have begun to see companies releasing synthetic mpox controls, which has helped labs better respond to unmet testing needs.

Better collaborations between test developers and clinical labs
 

For much of the outbreak in the US, just a handful of labs had partnered with the CDC to get mpox testing up and running. It wasn’t enough. Industry should do a better job of partnering with clinical labs to help ramp up testing capacity. If these relationships are established ahead of time as part of a nimble infrastructure, it will be easier to develop new tests and materials rapidly when new outbreaks emerge. In addition, collaborations can be used to expand and enhance testing strategies, such as enabling send-out testing or a variety of sample specimen types.

Looking ahead, infectious disease experts predict that the frequency of zoonotic pathogens spilling over into the human population will continue to increase due to climate change and human encroachment on animals’ natural habitats. It is more important than ever to plan ahead with new strategies for the rapid development of tests and controls. We must also establish stronger relationships between clinical laboratories and the developers of tests and controls so that we can respond quickly to new threats in the future.