An observational study in Monkeypox (Mpox), sponsored by Institute of Tropical Medicine, Belgium. Not yet recruiting at 1 site in Belgium. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-01-20.
Sponsored by Institute of Tropical Medicine, Belgium · Observational
POQS-Boosted is a prospective observational study during which individuals who received Booster vaccination against mpox with the MVA-BN vaccine will be invited to provide biological samples at multiple times over the course of two years.
Mpox caused a worldwide outbreak in 2022 and continues to circulate worldwide and causes sporadic cases in Belgium and elsewhere. In the last 10 days, the first cases infected with the probably more virulent clade Ib MPXV have been reported from men who have sex with men in Belgium, the Netherlands, and elsewhere, indicating circulating this viral clade in sexual networks. In Belgium, vaccination against mpox was ceased at the end of 2022 and evidence showed that antibody levels against MPXV have decreased since then, raising questions about sustained protectiveness and the potential for a new mpox outbreak to emerge.
POQS-Boosted is a prospective observational study during which individuals who received Booster vaccination against mpox with the MVA-BN vaccine will be invited to provide biological samples at multiple times over the course of two years.
72 studies on the registry are indexed under Mpox, Monkeypox; 30 are open to participants now.
This study's planned enrollment of 95 is below the median of 224 across 34 observational studies indexed under Mpox, Monkeypox.
Browse Mpox, Monkeypox studies →Institute of Tropical Medicine, Belgium is the lead sponsor of 104 studies on the registry; 21 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Individuals who received MVA-BN booster vaccination will be asked to participate in "POQS-Boosted"
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
1. Past or current MPXV infection
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Orthopoxvirus-specific serum binding and neutralising antibody titre
To describe the evolution of the orthopoxvirus-specific serum antibody response up to two years after MVA-BN booster vaccination
Time frame: from enrollment to the end of follow up at 2 years
Orthopoxvirus-specific systemic T- and B cell-mediated immune responses to MPXV
To describe the evolution of the orthopoxvirus-specific systemic cellular immune response up to two years after MVA-BN booster vaccination
Time frame: from enrollment up to 2 years
MPXV-specific IgA in saliva and anorectal samples; T and B cell-mediated immune responses to MPXV, measured on saliva and anorectal samples
To describe the evolution of the orthopoxvirus-specific mucosal antibody \& cellular immune response up to two years after MVA-BN booster vaccination
Time frame: from enrolment up to two years
Plan to share: Undecided
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
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Institute of Tropical Medicine, Belgium →