title: Non-vector-borne transmission of Zika virus: A systematic review.
abstract: BACKGROUND
  Increasing numbers of confirmed cases of Zika virus (ZIKV) infection resulting from non-mosquito-borne transmission have been reported.
  
  
  METHODS
  We performed a systematic literature review (PRISMA guidelines) on intrauterine, intrapartum, sexual and animal bite ZIKV transmission. The presence of the virus in breast milk, urine, saliva and blood transfusions was also reviewed.
  
  
  RESULTS
  The search resulted in 285 papers of possible relevance, of which we included 53 in the systematic review. Mother-to-child transmission was most frequently described with adverse infant outcomes including microcephaly, intracranial calcification and fetal death. Zika virus RNA has been detected in amniotic fluid, breast milk, seminal fluid, saliva, urine and blood. Semen and blood products have proved to be infectious. Male-to-female and male-to-male ZIKV transmission is documented. There are contradictory results concerning the infectiousness of breast milk and urine and data on saliva, animal bites, transplantation, needlestick injury and laboratory work are inconclusive.
  
  
  CONCLUSIONS
  Our systematic analysis shows that non-vector-borne ZIKV transmission plays a role in the spread of ZIKV and has great societal impact. It has important public health implications for the prevention and control of ZIKV globally and will be a basis for policy and further research.
authors.affiliation: University of Zurich Centre for Travel Medicine, WHO Collaborating Centre for Travellers' Health, Institute for Epidemiology, Biostatistics and Prevention, Hirschengraben 84, 8001 Zurich, Switzerland.
authors.forename: Franca
authors.initials: F
authors.lastname: Grischott
authors.affiliation: University of Zurich Centre for Travel Medicine, WHO Collaborating Centre for Travellers' Health, Institute for Epidemiology, Biostatistics and Prevention, Hirschengraben 84, 8001 Zurich, Switzerland.
authors.forename: Milo
authors.initials: M
authors.lastname: Puhan
authors.affiliation: University of Zurich Centre for Travel Medicine, WHO Collaborating Centre for Travellers' Health, Institute for Epidemiology, Biostatistics and Prevention, Hirschengraben 84, 8001 Zurich, Switzerland; Swiss Tropical and Public Health Institute, Department of Medicine and Diagnostics, University of Basel, Socinstrasse 57, 4051 Basel, Switzerland.
authors.forename: Christoph
authors.initials: C
authors.lastname: Hatz
authors.affiliation: University of Zurich Centre for Travel Medicine, WHO Collaborating Centre for Travellers' Health, Institute for Epidemiology, Biostatistics and Prevention, Hirschengraben 84, 8001 Zurich, Switzerland. Electronic address: patricia.schlagenhauf@uzh.ch.
authors.forename: Patricia
authors.initials: P
authors.lastname: Schlagenhauf
mesh_terms: D000818:Animals; D005260:Female; D006801:Humans; D018445:Infectious Disease Transmission, Vertical; D008297:Male; D008831:Microcephaly / Q000209:etiology / Q000821:virology; D008895:Milk, Human / Q000821:virology; D000072138:Mosquito Vectors / Q000821:virology; D012463:Saliva / Q000821:virology; D015229:Sexually Transmitted Diseases, Viral; D000071244:Zika Virus / Q000302:isolation & purification*; D000071243:Zika Virus Infection / Q000097:blood / Q000635:transmission* / Q000652:urine / Q000821:virology*
keywords: Microcephaly; Non-vector-borne transmission; Sexual transmission; Transfusion; Zika virus