May 29, 2026

Mpox

Performance of Five Mpox Antigen-based Rapid Diagnostic Tests Tested on Lesion Swabs from Patients with Suspected Mpox from the Kinshasa Province of DR Congo: A Diagnostic Accuracy Study
These are the results of a retrospective diagnostic accuracy study using lesion swabs from patients from a WHO transmission study with suspected mpox in nine health zones of Kinshasa province in DR Congo from February 12 to June 28, 2025, supplemented by PCR-negative swabs from consenting patients from other research studies. Five antigen-based RDTs were assessed, with results compared against the RADI FAST Mpox PCR assay. The primary outcome of diagnostic accuracy, as measured by sensitivity and specificity in tests from all patients, was assessed in DR Congo by operators masked to the results of other assays. Analytical sensitivity was evaluated using MPXV clade Ib isolates at the Geneva University Hospitals (Geneva, Switzerland). The best performing assay, from Guangdong Wesail Biotech, had a sensitivity of 77·3% (95% CI 68·0–84·5; 75 of 97) and specificity of 93·5% (86·6–97·0; 87 of 93). The Hangzhou Testsea Biotechnology assay had a similar performance Tests with moderate sensitivity and high specificity were by Beijing Hotgen Biotech and Contipharma. The NG Biotech assay had the lowest sensitivity but a similarly high specificity.

COVID: The Late Phase/PASC/Long COVID

A Causal Link Between Autoantibodies and Neurological Symptoms in Long COVID
Acute SARS-CoV-2 infection triggers the de novo production of diverse, functional autoantibodies (AABs) that remain elevated in Long COVID (LC), but their pathogenic role remains unclear. Using tissue-based immunofluorescence, ELISA, human protein array, and mass spectrometry assays, this group identified a broad range of AAB targets among individuals with LC. Individuals with neurocognitive symptoms showed increased AABs against central nervous system (CNS) and peripheral nervous system proteins. Purified immunoglobulin G (IgG) reacted with human locus coeruleus, thalamus, adrenal gland, and thyroid and cross-reacted with mouse sciatic nerve and meninges. CNS-reactive AABs correlated with several neurological symptoms. MED20-targeting IgG from patients with LC showed enhanced antibody-dependent phagocytosis. Passive transfer of IgG from individuals with LC into mice induced fatigue-like behavior, loss of balance/coordination, thermal hyperalgesia, small fiber nerve damage, and increased pain-related neuronal activity, recapitulating patients’ symptoms. These findings suggest that targeting AABs might offer therapeutic benefits for this LC subgroup.