Footnotes

• Twitter @JosephTucker

• NER, CSO-U and TG-B contributed equally.

• Contributors OE, JDT and JI conceived the idea for the study. NER drafted the paper. NER, KMT and JDT performed data acquisition and data analysis. CSO-U, TG-B, KMT, UN, DO, AZM, II, JO, TB and WT reviewed drafts and provided written feedback. JI, JDT and OE edited the paper for critical content. All authors contributed substantially to the preparation of this manuscript. All authors have read and approved the manuscript.

• Funding The study is funded by Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Grant number: 1UG3HD096929. The authors are also funded by the National Institute of Mental Health (R00MH104154, R34MH109359 and R34MH119963) and National Institute of Allergy and Infectious Diseases (P30AI50410 and K24AI143471).

• Competing interests None declared.

• Provenance and peer review Not commissioned; externally peer reviewed.