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Volume 32, Number 2—February 2026
Dispatch
Multiplex PCR to Differentiate Monkeypox Virus Clades
Table 1
Assay interpretation of multiplex PCR to differentiate monkeypox virus clades from the United Kingdom and Nigeria*
| Result | Probe |
||||
|---|---|---|---|---|---|
| Clade I (T46417C, G46421A, A46427C, C46435T) | Clade Ib (Δ19,128–20,270) | Non-IIb (G183695, C183696) | Clade IIb (G183695A, C183696T) | Lineage B.1 (C84587T) | |
| Clade Ia | Positive | Negative | Positive | Negative | Negative |
| Clade Ib | Positive | Positive | Positive | Negative | Negative |
| Clade IIa | Negative | Negative | Positive | Negative | Negative |
| Clade IIb | Negative | Negative | Negative | Positive | Negative |
| Lineage B.1 | Negative | Negative | Negative | Positive | Positive |
*Values in parentheses are the sites of nucleotide mutations each probe was assigned to.
1Members of the International Severe Acute Respiratory and Emerging Infection Consortium are listed at the end of this article.
2These authors contributed equally to this article.
Page created: January 26, 2026
Page updated: February 09, 2026
Page reviewed: February 09, 2026
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