Monkeypox ASymptomatic Shedding: Evaluation by Self-Sampling MPX-ASSESS (MPX-Assess)

Monkeypox (MPX) is a viral zoonosis, caused by the Monkeypox virus (MPXV), a DNA virus that belongs to the Orthopoxvirus genus and is closely related to the variola virus, the causative agent of smallpox. Until recently the spread of MPX was mainly confined to the Central African rainforest and to parts of West Africa. However, in May 2022, several cases of MPX were detected throughout Europe and Northern America, albeit with a different presentation than previously seen. Many questions remain on this new presentation of the disease: what the exact mode of transmission is, how contagious the virus really is and whether asymptomatic carriers exist. With this study the researchers aim to perform a close follow-up study of close contacts of MPX confirmed cases. Participants are recruited among high and very high risk contacts of confirmed monkeypox patients that presented to the ITM for diagnosis (index). Contacts that are asymptomatic (for symptoms compatible with MPXV infection according to national case definitions) at the time of recruitment will be enrolled. Contacts of the index case that are symptomatic at recruitment or become symptomatic during follow-up will be invited for sample collection at different timepoints until 21 days after contact as suspect cases.

Study Overview

• Status: Completed
• Conditions: Monkey Pox

• Study Type: Observational
• Enrollment (Actual): 27

Contacts and Locations

Study Locations

• Belgium
  • Antwerpen, Belgium, 2000
    • Institute Of Tropical Medicine Antwerp

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Participants are recruited among high and very high risk contacts of confirmed monkeypox patients that presented to the ITM for diagnosis (index). Contacts that are asymptomatic (for symptoms compatible with MPXV infection according to national case definitions) at the time of recruitment will be enrolled.

Description

Inclusion Criteria:

1. Be a high risk or very high-risk contact of a laboratory confirmed monkeypox case, with:

   • Very high-risk contact:

     • Sexual partner(s)
     • Prolonged skin-to-skin contact while the patient had skin lesions

   • High risk contact

     • living in the same household or similar environment (e.g. camping, spending the night, etc.);
     • shared clothing, bedding, utensils, etc., while the patient had skin lesions
     • healthcare workers with unprotected contact (inadequate or no PPE)
2. Last exposure to the monkeypox index case of less than 21 days ago
3. Adult participants (≥ 18 years old) of any gender
4. Written informed consent is obtained from the participant

Exclusion Criteria:

1. Presenting with symptoms compatible with MPX:

   • an unexplained rash on any part of the body AND
   • one or more of the following symptoms: fever, headache, back pain, fatigue, lymphadenopathy (localised or generalised)
2. Inability or unwillingness to comply with the proposed follow-up schedule

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
MPX-Assess; Contacts of MPX index cases

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Secondary attack rate of MPXV infection in contacts, defined by PCR positivity on any sample	Secondary attack rate of MPXV infection in contacts, defined by PCR positivity on any sample	Until 21 days after contact with index case

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rate of seroconversion in contacts, defined as a positive IgG (immunoglobulineG) for monkeypox	To evaluate the rate of seroconversion in contacts (positive IgG for MPX) within 21 days after contact with index case	Until 21 days after contact with index case
Proportion of seroconversion in PCR positive contacts vs PCR negative contacts, defined as negative MPXV PCR in all samples until the end of the follow-up period	Proportion of seroconversion in PCR positive contacts vs PCR negative contacts, defined as negative MPXV PCR in all samples until the end of the follow-up period	Until 21 days after contact with index case
Time to seroconversion overall, in symptomatic and asymptomatic contacts, and in PCR positive and negative cases	Time to seroconversion overall, in symptomatic and asymptomatic contacts, and in PCR positive and negative cases	Until 21 days after contact with index case
Proportion of PCR positive participants with asymptomatic infection at time of first positive PCR	Proportion of PCR positive participants with asymptomatic infection at time of first positive PCR	Until 21 days after contact with index case
Proportion of PCR positive participants developing symptoms within the follow-up period	Proportion of PCR positive participants developing symptoms within the follow-up period	Until 21 days after contact with index case
Proportion of asymptomatic infections on number of contacts in follow-up. Asymptomatic infections are defined as contacts with positive MPXV PCR on any clinical sample, without development of any symptoms.	Proportion of asymptomatic infections on number of contacts in follow-up. Asymptomatic infections are defined as contacts with positive MPXV PCR on any clinical sample, without development of any symptoms within 3 weeks after exposure or within 1 week after PCR positivity, whichever follow-up is longer	within 3 weeks after exposure or within 1 week after PCR positivity, whichever follow-up is longer
Time from MPXV PCR positivity in any sample to appearance of any symptom overall and per mode of transmission (close personal contact; anal, vaginal or oral receptive sexual contact; and insertive sexual contact)	Time from MPXV PCR positivity in any sample to appearance of any symptom overall and per mode of transmission (close personal contact; anal, vaginal or oral receptive sexual contact; and insertive sexual contact)	at the end of the 3-week follow-up period
Time from MPXV PCR positivity in any sample to appearance of skin lesions	Time from MPXV PCR positivity in any sample to appearance of skin lesions	at the end of the 3-week follow-up period
Time from confirmed exposure to first PCR positivity	Time from confirmed exposure to first PCR positivity	at the end of the 3-week follow-up period
Time from confirmed exposure to appearance of any symptom	Time from confirmed exposure to appearance of any symptom	at the end of the 3-week follow-up period
Time from confirmed exposure to appearance of skin lesions	Time from confirmed exposure to appearance of skin lesions	at the end of the 3-week follow-up period
Description of the type of symptoms observed in monkeypox contacts	Description of the type of symptoms observed in monkeypox contacts within 3 weeks after last exposure	within 3 weeks after last exposure
Frequency of symptoms observed in monkeypox contacts	Frequency of symptoms observed in monkeypox contacts within 3 weeks after last exposure	within 3 weeks after last exposure
Timing of symptoms observed in monkeypox contacts	Timing of symptoms observed in monkeypox contacts within 3 weeks after last exposure	within 3 weeks after last exposure
Distribution of skin lesions for sexual contacts versus close personal contacts. (per body surface and per category: local vs generalized skin lesions)	Distribution of skin lesions for sexual contacts versus close personal contacts. (per body surface and per category: local vs generalized skin lesions)	at the end of the 3-week follow-up period
Proportion of contacts presenting with systemic symptoms after sexual exposure versus those with close personal contacts exposure	Proportion of contacts presenting with systemic symptoms after sexual exposure versus those with close personal contacts exposure	at the end of the 3-week follow-up period
Number of contacts with the defined risk and protective factors	Number of contacts with the defined risk and protective factors	At baseline
Proportion of presence of defined factors in PCR positive contacts.	Proportion of presence of defined factors in PCR positive contacts.	Until the end of the 3-week follow-up period
Proportion of presence of defined factors in symptomatic PCR positive contacts	Proportion of presence of defined factors in symptomatic PCR positive contacts	Until the end of the 3-week follow-up period

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Presence of culturable virus in PCR positive samples from pre- or asymptomatic period	Presence of culturable virus in PCR positive samples from pre- or asymptomatic period	Until the end of the 3-week follow-up period

Collaborators and Investigators

• Sponsor: Institute of Tropical Medicine, Belgium
• Investigators: Principal Investigator: Laurens Liesenborghs, MD, Instituut van Tropische Geneeskunde Antwerpen

Study record dates

Study Major Dates

• Study Start (Actual): June 22, 2022
• Primary Completion (Actual): August 25, 2022
• Study Completion (Actual): August 25, 2022

Study Registration Dates

• First Submitted: June 21, 2022
• First Submitted That Met QC Criteria: July 1, 2022
• First Posted (Actual): July 5, 2022

Study Record Updates

• Last Update Posted (Actual): September 29, 2023
• Last Update Submitted That Met QC Criteria: September 28, 2023
• Last Verified: September 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Virus Diseases; Infections; DNA Virus Infections; Poxviridae Infections; Monkeypox
• Other Study ID Numbers: MPX-Assess

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No