Diagnostics

Diagnostics are needed for both clinical care and surveillance

The symptoms of mpox are not specific, particularly at early stages of infection, so diagnostics are needed to confirm diagnosis.

Multiple diagnostic use cases have been identified, including rapid near-patient testing, laboratory confirmation, multiplex testing for multiple pathogens, and discrimination of different MPXV subclades.

Diagnostics

Primary knowledge gaps identified in the Mpox R&D Roadmap 2026:

Diagnostic design and target selection

How can the design of new mpox antigen and molecular diagnostics be optimised according to different use cases?

Evaluation

How can standardised specimen collection and evaluation methods deliver comparable and reliable data on test performance?

Deployment

How can diagnostic tools best be deployed in clinical care and surveillance?

Diagnostics workplan

A CORC workplan for the diagnostics theme is in development.

Diagnostics background

Diagnostics are critical for clinical care and epidemiological surveillance (including One Health/environmental surveillance). Different diagnostic use cases will have different requirements, which need to be clearly defined. Important considerations include the breadth of detection – diagnostics may be designed to detect multiple orthopoxviruses, just MPXV or distinguish specific MPXV clades/genetic variants. Target product profiles for mpox diagnostics were developed by WHO in 2023[1].

Notable progress has been made in the mpox diagnostic landscape, with 12 products now WHO-prequalified; recent policy amendments have opened up pathways for affordable point-of-care tests. However, the current diagnostic portfolio is heavily weighted toward laboratory-based molecular assays requiring sophisticated equipment, trained personnel and stable electricity – resources often unavailable in outbreak epicentres. There is an urgent need for:

Rapid lateral flow antigen tests: Deployable at the community level, requiring minimal training, with results in 15–30 minutes.
Near point-of-care molecular tests: Affordable, portable molecular platforms suitable for use at decentralised sites and implementation in low-resource settings.
Multiplex assays: Tests capable of detecting multiple orthopoxviruses while differentiating MPXV, including MPXV clades, and multi-virus tests for differential diagnosis.

[1] https://www.who.int/publications/i/item/9789240076464

Challenges

Significant gaps persist across development, evaluation, regulation and implementation that limit the availability and deployment of diagnostics where they are most needed. Manufacturers, particularly smaller companies and academic developers, face significant barriers, including:

Target antigen selection: The need to balance specificity (MPXV-specific targets) versus pan-orthopox detection to account for antigenic conservation across strains presents technical challenges.
Unclear regulatory pathways: Confusion about requirements for WHO pre-qualification versus Africa CDC approval and lack of harmonisation creates duplication of effort and delays market entry.
Rapid outbreak dynamics: By the time a test is developed and approved, outbreak waves may have subsided, reducing commercial viability and manufacturer interest.
Limited market size: Mpox, while of public health concern, represents a small market compared to diseases such as TB or malaria, reducing investment incentives. Nevertheless, mpox cases are being detected in multiple countries, emphasising the global reach of this pathogen despite its characterisation as a limited market.

These factors contribute to an accessibility challenge: Several WHO-prequalified diagnostics are not readily accessible in high-burden settings such as Africa. Products may be approved but remain unavailable due to procurement barriers, lack of distribution networks, or insufficient market incentives for manufacturers. Ensuring production can cope with surges in demand during outbreaks is a further key challenge.