Funding for this research was provided by:
National Institute of Environmental Health Sciences (5R21ES025032)
National Center for Advancing Translational Sciences (UL1 TR001872)
Received: 10 May 2017
Accepted: 1 February 2018
First Online: 14 February 2018
Ethics approval and consent to participate
: We received ethical approval from the Committee for Human Research at the University of California, San Francisco, and from the Guatemalan Ministry of Health. Written consent was obtained after the consent was read to them in their preferred language, either Spanish or Mam.
: Not applicable.
: The authors declare that they have no competing interests.
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