nderstanding the burden of enteric fever in Africa and Asia: a study of transmission and antibiotic resistance to improve diagnostics and inform vaccine strategies

Not Applicable

Completed

• Conditions: Enteric fever; Infections and Infestations

• Registration Number: ISRCTN12131979
• Lead Sponsor: niversity of Oxford

Brief Summary

2017 Protocol article in https://www.ncbi.nlm.nih.gov/pubmed/28674145 protocol 2021 Results article in https://pubmed.ncbi.nlm.nih.gov/34798028/ (added 03/02/2022)

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2016-10-20
• Study Completion: 2020-12-31
• Last Update Posted: 21 February 2022

Recruitment & Eligibility

• Status: Completed
• Sex: All
• Target Recruitment: 423618

Inclusion Criteria

Census study, WASH and HUS survey:
Census participants will be the population (n =100,000, all ages) residing in a demarcated geographic area that is a known catchment population for each of the 3 typhoid surveillance sites. Participants will be recruited and consented as households.
1. Head of household / key informant is willing and competent to give informed consent for participation of the household in the study
2. Head of household / key informant is Male or Female, aged 18 years or above
3. Household is within the census area

Passive surveillance:
This component will include all patients presenting at any of the clinical surveillance sites in each country with a history of subjective fever >72 hours with or without objective fever on presentation.
1. Individual willing and competent to give informed consent if =18 years or the parent/legal guardian if participant <18 years;
2. Able to comply with study requirements
3. In addition those considered index cases (for the household contact component) must be resident in a household enrolled in the census survey

Household contacts (index cases):
From each site at least 73 households with index cases identified by the hospital surveillance component will be visited and all individual members of the household enrolled for the household contact study.
(Resident in same household as index case (identified from passive surveillance study) in whom enteric fever has been confirmed by a positive blood culture for S. Typhi or S. Paratyphi;
1. Individual willing and competent to give informed consent if =18 years or the parent/legal guardian if participant <18 years
2. Able to comply with study requirements

Serosurveillance:
Individual, age stratified participants (0-4 years, 5-9 years, 10-14 years >14 years) will be randomly selected from the census population.
1. Individual willing and competent to give informed consent if =18 years or the parent/legal guardian if participant <18 years
2. Male or female
3. Able to comply with study requirements
4. Resident in census area

Household contacts (of suspected chronic carriers identified in serosurvey):
Individuals resident in 50 households of suspected chronic carriers will be approached to request blood and stool samples in order to assess risk of infection in this group.
1. Resident in the same household as suspected chronic carrier identified in the serosurvey;
2. Individual willing and competent to give informed consent if =18 years or the parent/legal guardian if participant <18 years;
3. Able to comply with study requirements.

Exclusion Criteria

Census study, WASH and HUS survey:
1. Head of household/key informant not willing for household to participate
2. Unable to identify Head of household/key informant

Passive surveillance:
1. Previous enrolment into this component (e.g. from previous attendance at healthcare facility with persistent fever)
2. Other underlying disease which can be rapidly diagnosed such as Malaria in children (Blantyre)

Household contacts (index cases):
1. Not a resident of household of index case at time of his/her primary illness
2. Fever at presentation in index case confirmed not due to S. Typhi or Paratyphi fever
3. Deemed clinically unsuitable by the survey team (e.g. terminally ill)

Serosurveillance:
1. Not resident in the census area
2. Deemed clinically unsuitable by the survey team (e.g. terminally ill)

Household contacts (of suspected chronic carriers identified in serosurvey):
1. Not a resident of household of suspected chronic carrier at time of the visit
2. Deemed clinically unsuitable by the survey team (e.g. terminally ill)

Study & Design

• Study Type: Observational
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<br> The burden of enteric fever (typhoid and paratyphoid) in Africa and Asia, within the census populations, over a 2-year observation period, as determined by:<br> 1. The number of new cases confirmed by blood culture<br> 2. The rate of carriage per 1000 head of population<br> 3. The infection rate amongst household contacts of confirmed cases<br>

Secondary Outcome Measures

Name	Time	Method
<br> Antibody detection rates per 1000 head of population during the 2-year observation period to determine:<br> 1. Rate of chronic carriage<br> 2. Incidence of non-clinical typhoid<br> 3. Rates of infection arising from close contact with confirmed enteric fever and chronic carriers<br>