Monkeypox virus isolation from longitudinal samples from four patients to infer risk of onwards transmission: an interim analysis

H Callaby; K Emery; M Killip; T Rampling; K S Richards; C F Houlihan

doi:10.1016/j.jhin.2023.03.009

Monkeypox virus isolation from longitudinal samples from four patients to infer risk of onwards transmission: an interim analysis

J Hosp Infect. 2023 May:135:139-144. doi: 10.1016/j.jhin.2023.03.009. Epub 2023 Mar 21.

Authors

H Callaby¹, K Emery², M Killip², T Rampling³, K S Richards⁴, C F Houlihan⁵

Affiliations

¹ Rare and Imported Pathogens Laboratory, UKHSA, Porton Down, UK; Aberdeen Royal Infirmary, Aberdeen, UK. Electronic address: helen.callaby@nhs.scot.
² High Containment & Biological Services, Salisbury, UK.
³ Rare and Imported Pathogens Laboratory, UKHSA, Porton Down, UK; The Hospital for Tropical Diseases, University College London Hospital, London, UK; NIHR University College London Hospitals BRC, London, UK.
⁴ High Containment & Biological Services, Salisbury, UK; Faculty of Health and Life Sciences, Oxford Brookes University, Headington Campus, Oxford, UK.
⁵ Rare and Imported Pathogens Laboratory, UKHSA, Porton Down, UK; Clinical Virology, University College London Hospital, London, UK; Department of Infection and Immunity, University College London, London, UK.

Abstract

Monkeypox virus (mpxv) is a DNA virus in the Orthopoxvirus genus which causes Mpox (previously monkeypox). Symptoms include fever, lymphadenopathy and vesicular lesions. There is limited evidence for the duration of mpxv infectivity. This study used cell culture as a proxy for infectivity. Clinical samples from four patients with Mpox were inoculated into African green monkey kidney (Vero E6) cells and monitored for cytopathic effects (CPE). From one patient, infectious mpxv was recovered 25 days after illness onset. Infectious virus was not isolated from samples with an Orthopoxvirus polymerase chain reaction (PCR) Ct value over 31.0, nor from urine.

Keywords: Infectivity; Monkeypox; Mpox; Transmission; Viral culture.

MeSH terms

Animals
Chlorocebus aethiops
Monkeypox virus / genetics
Mpox (monkeypox)* / diagnosis
Polymerase Chain Reaction