Streptococcus Pyogenes Carriage Acquisition and Transmission Study

NCT05117528 | Completed

• 1 other identifier: LEO 24005
• Study Type: observational
• Target: 441
• Locations: 1 country
• Sites: 1

Brief Summary

Group A Streptococcus (GAS) is a bacteria which causes severe infections and leads to deadly diseases such as rheumatic heart disease which kills over 300,000 people a year globally, particularly in low-income countries. It is not know how GAS is spread between people, how often people carry GAS in their throat or on their skin without having symptoms, or what factors increase the chance of this occurring. It is important to understand these factors in order to know how to reduce GAS-related disease. This study will follow 444 people in The Gambia, over 12 months, taking samples from the throats and skin of people living in the same households, and asking questions about themselves and their behaviour, at regular intervals. By taking samples over time, the investigators hope to understand how common it is to carry GAS without having symptoms, how GAS is spread between people, and whether carrying GAS leads to more GAS infections in people or their household members. The study will use state-of-the-art techniques to look at the DNA of GAS bacteria that we find, and combine this with a mathematical model to investigate how different strains spread to people within and between households in the community.

Conditions

Group A Streptococcal Infection; Scabies; Microbial Colonization

Keywords

Group A Streptococcal skin colonization; Group A Streptococcal pharyngeal carriage; Group A Streptococcal transmission

Outcome Measures

Primary Outcomes (5)

• Prevalence of oropharyngeal swabs positive for GAS each month

  Oropharyngeal swabs taken at monthly visits will be plated for microbiological culture, and the presence of GAS determined by latex agglutination testing.

  Monthly visits

• Prevalence of normal skin swabs positive for GAS each month

  Normal skin swabs taken at monthly visits will be plated for microbiological culture, and the presence of GAS determined by latex agglutination testing.

  Monthly visits

• Incidence of GAS-positive oropharyngeal swabs

  Oropharyngeal swabs taken at each visit will be plated for microbiological culture, and the presence of GAS determined by latex agglutination testing. The incidence of positive swabs in person-years will be calculated

  1 year

• Incidence of GAS-positive normal skin swabs

  Normal skin swabs taken at each visit will be plated for microbiological culture, and the presence of GAS determined by latex agglutination testing. The incidence of positive swabs in person-years will be calculated

  1 year

• Change in GAS-positive swabs per month

  Seasonal changes in GAS-positivity will be assessed over the course of a year.

  1 year

Secondary Outcomes (11)

• Adjusted hazard ratio for GAS carriage depending on presence of relevant risk factors

  1 year

• Adjusted hazard ratio for GAS symptomatic infection depending on presence of relevant risk factors

  1 year

• Difference in GAS emm type diversity compared to other settings

  1 year

• The level of GAS tissue tropism

  1 year

• Prevalence of Group C streptococcal carriage

  Monthly

Eligibility Criteria

• Sex: all
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Sukuta is an area within the West Coast Region peri-urban conurbation of The Gambia, with a population of 47,048 in 2013, including 7,234 children aged under 5 years, and an average household size of 8.1. The Gambia is the smallest mainland country in Africa with a population of 1.9 million in 2013 and was ranked 174th in the world in the UN Human Development Index in 2017. Households within the 2013 boundaries of Sukuta will be randomly selected using a list of randomly generated GPS locations stratified by housing density (high, medium and low). All eligible and willing households identified using the GPS location list will be enrolled, until the target sample size of 45 households is reached. All individuals living within the households will be enrolled, with no age restrictions.

You may qualify if:

• Households must:
• Be within the boundary of Sukuta as determined by the 2013 census
• Have at least 3 members including at least one child under age 18
• Individuals must:
• Provide signed (or thumbprinted) informed consent for study participation (obtained from a parent or guardian for children under the age of 18
• Be willing and have capacity to participate and comply with the study protocol as judged by a member of the study team
• Be resident in the household, with no plans to move outside of the household during the period of study participation

You may not qualify if:

• Households:
• \- Less than 80% of individuals living in the household, as defined by the The Gambia Demographic and Health Survey 2013 definition, provide consent to participate
• Individuals:
• Consent not provided
• Has any condition or any other reason that may lead to difficulty or discomfort in obtaining all the necessary samples
• Is judged by the study team member to be unable or unlikely to participate and comply with the study protocol for the entire study period

Sponsors & Collaborators

• London School of Hygiene and Tropical Medicine: lead
• Wellcome Trust: collaborator

Study Sites (1)

MRC Unit The Gambia at LSHTM

Fajara, The Gambia

Location

Related Publications (2)

• de Crombrugghe G, Armitage EP, Keeley AJ, Senghore E, Camara F, Jammeh M, Bittaye A, Ceesay H, Ceesay I, Samateh B, Manneh M, Botquin G, Lakhloufi D, Delforge V, Bah SY, Hall JN, Schiavolin L, Turner CE, Marks M, de Silva TI, Botteaux A, Smeesters PR; MRCG StrepA Study Group. Household Molecular Epidemiology of Streptococcus pyogenes Carriage and Infection in The Gambia. J Infect Dis. 2025 Sep 15;232(3):550-559. doi: 10.1093/infdis/jiaf252.

  PMID: 40378280 DERIVED

• Armitage EP, de Crombrugghe G, Keeley AJ, Senghore E, Camara FE, Jammeh M, Bittaye A, Ceesay H, Ceesay I, Samateh B, Manneh M, Kampmann B, Turner CE, Kucharski A, Botteaux A, Smeesters PR, de Silva TI, Marks M; MRCG StrepA Study Group. Streptococcus pyogenes carriage and infection within households in The Gambia: a longitudinal cohort study. Lancet Microbe. 2024 Jul;5(7):679-688. doi: 10.1016/S2666-5247(24)00046-6. Epub 2024 May 9.

  PMID: 38735305 DERIVED

Biospecimen

Retention: SAMPLES WITH DNA

Oropharyngeal swabs Normal skin swabs Pyoderma wound swabs Blood Serum Dried Blood Spot Oral fluid Environmental swabs Settle plates

MeSH Terms

Conditions

Streptococcal Infections; Scabies; Communicable Diseases

Condition Hierarchy (Ancestors)

Gram-Positive Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Infections; Mite Infestations; Ectoparasitic Infestations; Skin Diseases, Parasitic; Parasitic Diseases; Skin Diseases, Infectious; Skin Diseases; Skin and Connective Tissue Diseases; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Edwin P Armitage, BMBS

  London School of Hygiene and Tropical Medicine

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 21, 2021
• First Posted: November 11, 2021
• Study Start: July 27, 2021
• Primary Completion: September 30, 2022
• Study Completion: September 30, 2022
• Last Updated: November 25, 2022

Record last verified: 2022-11

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR, ANALYTIC CODE
• Time Frame: Data used for manuscript preparation will be made available at the time of publication for as long as the journal makes it available.

Locations

TH (1)