NCT03087214

Brief Summary

The epidemiology and ecology of malaria in humans includes complex interactions between human hosts and mosquito vectors. These interactions are spatio-temporal in nature and are heavily dependent on transportation capabilities and seasonal conditions. Where and when infections are acquired is not well understood in the Greater Mekong Subregion (GMS), where there are numerous vectors, many with different behaviours and habitats. For example, many infections appear to be associated with forests or forest edges and some of the most important mosquito vectors in the region are forest dwellers (Obsomer, Defourny, and Coosemans 2007). Interventions that target houses at night-time (e.g. mosquito nets), have had limited success in the GMS, most likely because at least some infections are acquired during the day or outside of the home (Dolan et al. 1993; Luxemburger et al. 1994). While overall malaria incidence in the region appears to be declining, the disease remains persistent in small subregions, for example along international borders joining Thailand with Myanmar. It will be crucial for elimination efforts to address the persistent malaria in these regions, most likely requiring the use of novel and spatially targeted approaches. Increasingly, spatial data and analyses are used in disease research (Linard and Tatem 2012; Pybus et al. 2016; Tatem et al. 2012), however most spatial analyses are at aggregate scales, using data from provincial or state levels. More detailed studies have a single geographic reference point per individual in the study, frequently the home (Mosha et al. 2014; Parker et al. 2015). These studies allow researchers to investigate potential clustering of cases within and between houses ("hotspots") (Bejon et al. 2014; Bousema et al. 2012; Mosha et al. 2014). Even these detailed studies typically ignore the spaces in which people spend time outside of their home and where they may acquire infection: schools; places of worship and work; forest camps and temporary shelters. Given that many malaria infections in the GMS are acquired outside of the home, in areas that are not usually mapped, this information is important for developing strategies to prevent transmission and will be crucial for achieving elimination. Researchers in other substantive areas have already begun mapping the movement patterns of study subjects so that exposure to a variety of environmental exposures outside of the home can be assessed (Matthews and Yang 2013; Vazquez-Prokopec et al. 2010). Early approaches relied on travel surveys or travel diaries, both having bias of unknown magnitude. Modern wearable global positioning satellite (GPS) instruments (loggers or trackers) and geographic information science (GIS) enable detailed mapping and quantification of human movement patterns. Through analysing differences in the movement patterns between humans who do versus those that do not acquire infectious diseases, it may be possible to identify a narrower set of geographic spaces in which disease transmission is occurring. Public health interventions could then target those risk areas. Most of these detailed studies have been done in economically developed settings and urban environments. Infectious diseases such as malaria remain persistent in resource-poor, rural, and remote areas - the very regions that are least likely to be studied with detailed approaches (Sachs and Malaney 2002).

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
54

participants targeted

Target at P25-P50 for all trials

Timeline
Completed

Started Mar 2017

Shorter than P25 for all trials

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

March 8, 2017

Completed
6 days until next milestone

Study Start

First participant enrolled

March 14, 2017

Completed
8 days until next milestone

First Posted

Study publicly available on registry

March 22, 2017

Completed
11 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

February 17, 2018

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

February 17, 2018

Completed
Last Updated

January 8, 2019

Status Verified

January 1, 2019

Enrollment Period

11 months

First QC Date

March 8, 2017

Last Update Submit

January 7, 2019

Conditions

Outcome Measures

Primary Outcomes (5)

  • Time-stamped locations

    A series of spatial data sets that can then be mapped and analyzed

    1 year

  • The latitude and longitude of the GPS logging reading.

    The GPS logging devices will automatically take a reading every 30 minutes.

    1 year

  • The elevation of the GPS logging reading.

    The GPS logging devices will automatically take a reading every 30 minutes.

    1 year

  • Date and time of the GPS logging reading.

    The GPS logging devices will automatically take a reading every 30 minutes.

    1 year

  • Acceptability among participants about carrying the GPS logging device during

    Participants will also be interviewed throughout the study period and one of the research questions

    1 year

Secondary Outcomes (1)

  • Questionnaires

    1 year

Eligibility Criteria

Age20 Years+
Sexall
Age GroupsAdult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

* The participants are Karen or Burmese ethnic group * Participants must be above 20 years of age * capable of keeping track of the device * walking beyond village boundaries * willing to consent to the study

You may qualify if:

  • The participants are Karen or Burmese ethnic group
  • Participants must be above 20 years of age
  • Capable of keeping track of the device
  • Walking beyond village boundaries
  • Willing to consent to the study

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Shoklo Malaria Research Unit

Mae Sot, Changwat Tak, Thailand

Location

Study Design

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

Study Record Dates

First Submitted

March 8, 2017

First Posted

March 22, 2017

Study Start

March 14, 2017

Primary Completion

February 17, 2018

Study Completion

February 17, 2018

Last Updated

January 8, 2019

Record last verified: 2019-01

Data Sharing

IPD Sharing
Will share

Locations