title: Characteristics of a dengue outbreak in a remote pacific island chain--Republic of The Marshall Islands, 2011-2012.
abstract: Dengue is a potentially fatal acute febrile illness caused by four mosquito-transmitted dengue viruses (DENV-1-4). Although dengue outbreaks regularly occur in many regions of the Pacific, little is known about dengue in the Republic of the Marshall Islands (RMI). To better understand dengue in RMI, we investigated an explosive outbreak that began in October 2011. Suspected cases were reported to the Ministry of Health, serum specimens were tested with a dengue rapid diagnostic test (RDT), and confirmatory testing was performed using RT-PCR and IgM ELISA. Laboratory-positive cases were defined by detection of DENV nonstructural protein 1 by RDT, DENV nucleic acid by RT-PCR, or anti-DENV IgM antibody by RDT or ELISA. Secondary infection was defined by detection of anti-DENV IgG antibody by ELISA in a laboratory-positive acute specimen. During the four months of the outbreak, 1,603 suspected dengue cases (3% of the RMI population) were reported. Of 867 (54%) laboratory-positive cases, 209 (24%) had dengue with warning signs, six (0.7%) had severe dengue, and none died. Dengue incidence was highest in residents of Majuro and individuals aged 10-29 years, and ∼95% of dengue cases were experiencing secondary infection. Only DENV-4 was detected by RT-PCR, which phylogenetic analysis demonstrated was most closely related to a virus previously identified in Southeast Asia. Cases of vertical DENV transmission, and DENV/Salmonella Typhi and DENV/Mycobacterium leprae co-infection were identified. Entomological surveys implicated water storage containers and discarded tires as the most important development sites for Aedes aegypti and Ae. albopictus, respectively. Although this is the first documented dengue outbreak in RMI, the age groups of cases and high prevalence of secondary infection demonstrate prior DENV circulation. Dengue surveillance should continue to be strengthened in RMI and throughout the Pacific to identify and rapidly respond to future outbreaks.
authors.affiliation: Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America; Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, San Juan, Puerto Rico.
authors.forename: Tyler M
authors.initials: TM
authors.lastname: Sharp
authors.affiliation: Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, San Juan, Puerto Rico.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Mackay
authors.affiliation: Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, San Juan, Puerto Rico.
authors.forename: Gilberto A
authors.initials: GA
authors.lastname: Santiago
authors.affiliation: Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, San Juan, Puerto Rico.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Hunsperger
authors.affiliation: World Health Organization, Division of Pacific Technical Support, Suva, Fiji.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Nilles
authors.affiliation: Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, San Juan, Puerto Rico.
authors.forename: Janice
authors.initials: J
authors.lastname: Perez-Padilla
authors.affiliation: Majuro Hospital, Majuro, Republic of the Marshall Islands.
authors.forename: Kinisalote S
authors.initials: KS
authors.lastname: Tikomaidraubuta
authors.affiliation: Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, San Juan, Puerto Rico.
authors.forename: Candimar
authors.initials: C
authors.lastname: Colon
authors.affiliation: Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, San Juan, Puerto Rico.
authors.forename: Manuel
authors.initials: M
authors.lastname: Amador
authors.affiliation: Division of Global Migration and Quarantine, Centers for Disease Control and Prevention, Honolulu, Hawaii, United States of America.
authors.forename: Tai-Ho
authors.initials: TH
authors.lastname: Chen
authors.affiliation: Majuro Hospital, Majuro, Republic of the Marshall Islands.
authors.forename: Paul
authors.initials: P
authors.lastname: Lalita
authors.affiliation: Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, San Juan, Puerto Rico.
authors.forename: Jorge L
authors.initials: JL
authors.lastname: Muñoz-Jordán
authors.affiliation: Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, San Juan, Puerto Rico.
authors.forename: Roberto
authors.initials: R
authors.lastname: Barrera
authors.affiliation: Ministry of Health, Majuro, Republic of the Marshall Islands.
authors.forename: Justina
authors.initials: J
authors.lastname: Langidrik
authors.affiliation: Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, San Juan, Puerto Rico.
authors.forename: Kay M
authors.initials: KM
authors.lastname: Tomashek
mesh_terms: D000293:Adolescent; D000328:Adult; D000330:Aedes / Q000821:virology; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002648:Child; D002675:Child, Preschool; D060085:Coinfection; D003715:Dengue / Q000097:blood / Q000453:epidemiology* / Q000821:virology; D003716:Dengue Virus / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D004196:Disease Outbreaks; D062665:Epidemiological Monitoring; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D007223:Infant; D007918:Leprosy / Q000453:epidemiology* / Q000382:microbiology; D008297:Male; D008849:Micronesia / Q000453:epidemiology; D008875:Middle Aged; D009166:Mycobacterium leprae / Q000235:genetics / Q000302:isolation & purification; D015995:Prevalence; D012485:Salmonella typhi / Q000235:genetics / Q000302:isolation & purification; D014435:Typhoid Fever / Q000453:epidemiology* / Q000382:microbiology; D017361:Viral Nonstructural Proteins / Q000235:genetics
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D017361:Viral Nonstructural Proteins