Mapping imported malaria in Bangladesh using parasite genetic and human mobility data
- Harvard T H Chan School of Public Health, United States
- Johns Hopkins Bloomberg School of Public Health, United States
- Mahidol University, Thailand
- Wellcome Sanger Institute, United Kingdom
- Chittagong Medical College, Bangladesh
- Chittagong Medical College Hospital, Bangladesh
- Shaheed Suhrawardy Medical College, Bangladesh
- BRAC Centre, Bangladesh
- National Malaria Elimination Programme, Bangladesh
- World Health Organization, Bangladesh
- Directorate General of Health Services, Bangladesh
- The WorldWide Antimalarial Resistance Network (WWARN), Thailand
- Telenor Group, Norway
- Cited 14
- Views 2,751
- Annotations
Abstract
For countries aiming for malaria elimination, travel of infected individuals between endemic areas undermines local interventions. Quantifying parasite importation has therefore become a priority for national control programs. We analyzed epidemiological surveillance data, travel surveys, parasite genetic data, and anonymized mobile phone data to measure the spatial spread of malaria parasites in southeast Bangladesh. We developed a genetic mixing index to estimate the likelihood of samples being local or imported from parasite genetic data and inferred the direction and intensity of parasite flow between locations using an epidemiological model integrating the travel survey and mobile phone calling data. Our approach indicates that, contrary to dogma, frequent mixing occurs in low transmission regions in the southwest, and elimination will require interventions in addition to reducing imported infections from forested regions. Unlike risk maps generated from clinical case counts alone, therefore, our approach distinguishes areas of frequent importation as well as high transmission.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (U54GM088558)
- Hsiao-Han Chang
Burroughs Wellcome Fund
- Amy Wesolowski
Bill and Melinda Gates Foundation (CPT000390)
- Ipsita Sinha
- Sazid Ibna Zaman
- Richard J Maude
Medical Research Council (G0600718)
- Christopher G Jacob
- Eleanor Drury
- Sonia Gonçalves
- Mihir Kekre
- Dominic Kwiatkowski
National Institute of General Medical Sciences (R35GM124715-02)
- Caroline Buckee
Bill and Melinda Gates Foundation (OPP1118166)
- Christopher G Jacob
- Olivo Miotto
- Caroline Buckee
Bill and Melinda Gates Foundation (OPP1129596)
- Ipsita Sinha
- Sazid Ibna Zaman
- Richard J Maude
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Neil M Ferguson, Imperial College London, United Kingdom
Publication history
- Received: November 9, 2018
- Accepted: March 14, 2019
- Accepted Manuscript published: April 2, 2019 (version 1)
- Version of Record published: April 23, 2019 (version 2)
Copyright
© 2019, Chang et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 2,751
- Page views
-
- 389
- Downloads
-
- 14
- Citations
Article citation count generated by polling the highest count across the following sources: PubMed Central, Scopus, Crossref.
Download links
Downloads (link to download the article as PDF)
Download citations (links to download the citations from this article in formats compatible with various reference manager tools)
Open citations (links to open the citations from this article in various online reference manager services)
Further reading
-
- Epidemiology and Global Health
- Microbiology and Infectious Disease
Poor diet and lifestyle exposures are implicated in substantial global increases in non-communicable disease burden in low-income, remote, and Indigenous communities. This observational study investigated the contribution of the fecal microbiome to influence host physiology in two Indigenous communities in the Torres Strait Islands: Mer, a remote island where a traditional diet predominates, and Waiben a more accessible island with greater access to takeaway food and alcohol. Counterintuitively, disease markers were more pronounced in Mer residents. However, island-specific differences in disease risk were explained, in part, by microbiome traits. The absence of Alistipes onderdonkii, for example, significantly (p=0.014) moderated island-specific patterns of systolic blood pressure in multivariate-adjusted models. We also report mediatory relationships between traits of the fecal metagenome, disease markers, and risk exposures. Understanding how intestinal microbiome traits influence response to disease risk exposures is critical for the development of strategies that mitigate the growing burden of cardiometabolic disease in these communities.
-
- Epidemiology and Global Health
- Medicine
Background:
Since 2015, the World Health Organisation (WHO) recommends immediate initiation of antiretroviral therapy (ART) for all HIV-positive patients. Epidemiological evidence points to important health benefits of immediate ART initiation; however, the policy’s impact on the economic aspects of patients' lives remains unknown.
Methods:
We conducted a stepped-wedge cluster-randomised controlled trial in Eswatini to determine the causal impact of immediate ART initiation on patients’ individual- and household-level economic outcomes. Fourteen healthcare facilities were non-randomly matched into pairs and then randomly allocated to transition from the standard of care (ART eligibility at CD4 counts of <350 cells/mm3 until September 2016 and <500 cells/mm3 thereafter) to the ‘Early Initiation of ART for All’ (EAAA) intervention at one of seven timepoints. Patients, healthcare personnel, and outcome assessors remained unblinded. Data were collected via standardised paper-based surveys with HIV-positive adults who were neither pregnant nor breastfeeding. Outcomes were patients’ time use, employment status, household expenditures, and household living standards.
Results:
A total sample of 3019 participants were interviewed over the duration of the study. The mean number of participants approached at each facility per time step varied from 4 to 112 participants. Using mixed-effects negative binomial regressions accounting for time trends and clustering at the level of the healthcare facility, we found no significant difference between study arms for any economic outcome. Specifically, the EAAA intervention had no significant effect on non-resting time use (RR = 1.00 [CI: 0.96, 1.05, p=0.93]) or income-generating time use (RR = 0.94, [CI: 0.73,1.20, p=0.61]). Employment and household expenditures decreased slightly but not significantly in the EAAA group, with risk ratios of 0.93 [CI: 0.82, 1.04, p=0.21] and 0.92 [CI: 0.79, 1.06, p=0.26], respectively. We also found no significant treatment effect on households’ asset ownership and living standards (RR = 0.96, [CI 0.92, 1.00, p=0.253]). Lastly, there was no evidence of heterogeneity in effect estimates by patients’ sex, age, education, timing of HIV diagnosis and ART initiation.
Conclusions:
Our findings do not provide evidence that should discourage further investments into scaling up immediate ART for all HIV patients.
Funding:
Funded by the Dutch Postcode Lottery in the Netherlands, Alexander von Humboldt-Stiftung (Humboldt-Stiftung), the Embassy of the Kingdom of the Netherlands in South Africa/Mozambique, British Columbia Centre of Excellence in Canada, Doctors Without Borders (MSF USA), National Center for Advancing Translational Sciences of the National Institutes of Health and Joachim Herz Foundation.
Clinical trial number:
NCT02909218 and NCT03789448.
