Design: Prospective diagnostic accuracy study with usability assessment
Population: 300 people with suspected mpox at six facilities in Uganda
Primary outcome: Sensitivity and specificity against laboratory qPCR
Effect: MPXV sensitivity 98.5% (95% CI 95.6–99.5); specificity 96.2% (90.5–98.5)

This prospective diagnostic accuracy study enrolled 300 consecutive people meeting the WHO suspected-case definition for mpox, with an active skin lesion, at six facilities in Kampala and Wakiso, Uganda. Lesion swabs were run on Dragonfly, a sample-to-result molecular platform, and confirmed by laboratory quantitative PCR.

Of the 300, 196 (65%) had mpox. Against PCR, Dragonfly was 98.5% sensitive (95% CI 95.6–99.5) and 96.2% specific (90.5–98.5) for monkeypox virus, with results in under 40 minutes. Front-line staff found it acceptable, while noting training and supply needs.

The study was done in a high-prevalence outbreak setting with high viral loads (median cycle threshold 21), which flatters sensitivity. Performance across other clades, low-prevalence settings and cost-effectiveness are not yet known.

Swab an active skin lesion — unroofed vesicle or pustule — for any suspected mpox case.
Point-of-care molecular testing can confirm mpox in under an hour where laboratory PCR is distant.
In low-prevalence settings, confirm a positive point-of-care result with laboratory PCR.
Isolate and notify on clinical suspicion without waiting for any test result.
Test for HIV and other sexually transmitted infections in confirmed cases.

Why it matters

It shows mpox diagnosis can move from the reference laboratory to the clinic where outbreaks actually happen.

The statistics, in plain English

Sensitivity of 98.5% means about 1 or 2 in 100 true cases were missed. Specificity of 96.2% means about 4 in 100 people without mpox tested positive. In a setting where most suspected cases are real, as here, a positive result is very reliable; where mpox is rare, the same false-positive rate produces a larger share of wrong positives.