More point of care tests needed in mpox outbreak, expert says

The mpox outbreak has spurred urgent calls for vaccines for the African continent. But one expert interviewed by Devex also underscored the need for more testing options that are fast, accurate, and accessible at the community level. Most of the tests right now in Africa are centralized in a laboratory, Dr. Marta Fernández Suárez, chief technology officer for the diagnostics alliance FIND, told Devex. This means it can take days for results to come out and that the test is not easily accessible to communities. There are some point of care tests available, and FIND is conducting an evaluation of their performance, but she said currently these tests are not widely accessible or even introduced in most countries. “We need accelerated development and approval of accurate, rapid point of care diagnostics. There are some tests in the pipeline, but more funding is needed to validate more and quickly,” according to a FIND spokesperson. “Point of care tests help tailor targeted interventions at community level more quickly.” Several manufacturers developed mpox tests following the World Health Organization’s declaration of a public health emergency in 2022, but many of these tests are not commercially available today due to a lack of market. “When the declaration of the public health emergency of international concern [in 2022] happened, everybody was thinking, ‘OK, this may become COVID. So let me develop the product,’” Fernández Suárez said. However, due to a lack of market, several manufacturers have not pushed through to clinical trials. “Most of these tests are stopping at the validation stage because that's when you need to start getting prospective samples or sometimes retrospective samples to do the clinical performance. And those become very costly, especially in an outbreak where the samples are very scarce,” Fernández Suárez said. In addition, many countries did not create expedited regulatory mechanisms to allow for emergency use of such tests. But that may change if this outbreak becomes larger and countries start putting emergency mechanisms in place and more mpox samples become available, Fernández Suárez said. She said they’re currently looking at tests that can differentiate between clade 1 and clade 2. Most tests are still unable to differentiate clade 1b however because it’s relatively new. Mpox clade 1b is the current variant of concern that has spread rapidly in the Democratic Republic of Congo and that, according to WHO, appears to be spreading mainly through sexual networks. “We are updating our diagnostics landscape to confirm detection of clade 1, especially for clade 1b. Many PCR tests have a generic target that can detect any virus in that family (including clade 1b), but the challenge is that you may be detecting a different pox virus and not mpox,” according to the spokesperson. There are currently no self-tests available for mpox. “For mpox it’s a bit trickier when we think about the sample, because, as you know, the recommended sample for mpox is the lesion, the ulcer. In the absence of ulcers, or if the ulcers are dry, then it's either recto-anal or oropharyngeal, which is something that … wouldn't be possible through a self-test, or it would be very unlikely that we would get good performance today,” Fernández Suárez said. FIND said capacity and funding is needed to expand manufacturing of mpox diagnostics in Africa. “[N]o mpox tests are manufactured in Africa that we're aware of,” according to the spokesperson. “However, we will update our landscape to see if there are any new developments in the region. There are African test manufacturers who are working in this area.” FIND has a partnership with Diatropix, a nonprofit manufacturing facility under the Institut Pasteur de Dakar in Senegal, to develop rapid diagnostic tests for infectious diseases and ensure their regional manufacturing for outbreak response.