title: Zika virus outbreak on Yap Island, Federated States of Micronesia.
abstract: BACKGROUND
  In 2007, physicians on Yap Island reported an outbreak of illness characterized by rash, conjunctivitis, and arthralgia. Although serum from some patients had IgM antibody against dengue virus, the illness seemed clinically distinct from previously detected dengue. Subsequent testing with the use of consensus primers detected Zika virus RNA in the serum of the patients but no dengue virus or other arboviral RNA. No previous outbreaks and only 14 cases of Zika virus disease have been previously documented.
  
  
  METHODS
  We obtained serum samples from patients and interviewed patients for information on clinical signs and symptoms. Zika virus disease was confirmed by a finding of Zika virus RNA or a specific neutralizing antibody response to Zika virus in the serum. Patients with IgM antibody against Zika virus who had a potentially cross-reactive neutralizing-antibody response were classified as having probable Zika virus disease. We conducted a household survey to estimate the proportion of Yap residents with IgM antibody against Zika virus and to identify possible mosquito vectors of Zika virus.
  
  
  RESULTS
  We identified 49 confirmed and 59 probable cases of Zika virus disease. The patients resided in 9 of the 10 municipalities on Yap. Rash, fever, arthralgia, and conjunctivitis were common symptoms. No hospitalizations, hemorrhagic manifestations, or deaths due to Zika virus were reported. We estimated that 73% (95% confidence interval, 68 to 77) of Yap residents 3 years of age or older had been recently infected with Zika virus. Aedes hensilli was the predominant mosquito species identified.
  
  
  CONCLUSIONS
  This outbreak of Zika virus illness in Micronesia represents transmission of Zika virus outside Africa and Asia. Although most patients had mild illness, clinicians and public health officials should be aware of the risk of further expansion of Zika virus transmission.
authors.affiliation: Division of Vector-Borne Infectious Diseases, National Center for Zoonotic, Vector-Borne, and Enteric Diseases, Centers for Disease Control and Prevention, Fort Collins, CO 80521, USA.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Duffy
authors.forename: Tai-Ho
authors.initials: TH
authors.lastname: Chen
authors.forename: W Thane
authors.initials: WT
authors.lastname: Hancock
authors.forename: Ann M
authors.initials: AM
authors.lastname: Powers
authors.forename: Jacob L
authors.initials: JL
authors.lastname: Kool
authors.forename: Robert S
authors.initials: RS
authors.lastname: Lanciotti
authors.forename: Moses
authors.initials: M
authors.lastname: Pretrick
authors.forename: Maria
authors.initials: M
authors.lastname: Marfel
authors.forename: Stacey
authors.initials: S
authors.lastname: Holzbauer
authors.forename: Christine
authors.initials: C
authors.lastname: Dubray
authors.forename: Laurent
authors.initials: L
authors.lastname: Guillaumot
authors.forename: Anne
authors.initials: A
authors.lastname: Griggs
authors.forename: Martin
authors.initials: M
authors.lastname: Bel
authors.forename: Amy J
authors.initials: AJ
authors.lastname: Lambert
authors.forename: Janeen
authors.initials: J
authors.lastname: Laven
authors.forename: Olga
authors.initials: O
authors.lastname: Kosoy
authors.forename: Amanda
authors.initials: A
authors.lastname: Panella
authors.forename: Brad J
authors.initials: BJ
authors.lastname: Biggerstaff
authors.forename: Marc
authors.initials: M
authors.lastname: Fischer
authors.forename: Edward B
authors.initials: EB
authors.lastname: Hayes
mesh_terms: D000293:Adolescent; D000328:Adult; D000330:Aedes; D017677:Age Distribution; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D018771:Arthralgia / Q000821:virology; D002648:Child; D002675:Child, Preschool; D003236:Conjunctivitis, Viral / Q000821:virology; D003716:Dengue Virus / Q000276:immunology; D004196:Disease Outbreaks; D005076:Exanthema / Q000821:virology; D005334:Fever / Q000209:etiology; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D007223:Infant; D007303:Insect Vectors; D008849:Micronesia / Q000453:epidemiology; D008875:Middle Aged; D011159:Population Surveillance; D012367:RNA, Viral / Q000097:blood; D017678:Sex Distribution; D055815:Young Adult; D000071244:Zika Virus / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D000071243:Zika Virus Infection / Q000150:complications / Q000453:epidemiology* / Q000821:virology
chemical_list: D000914:Antibodies, Viral; D007075:Immunoglobulin M; D012367:RNA, Viral