title: No evidence of chikungunya virus and antibodies shortly before the outbreak on Sri Lanka.
abstract: A massive outbreak of chikungunya disease occurred on Sri Lanka in 2006. Reasons for the explosive nature of the epidemic are being intensively discussed. According to recognised and anecdotal concepts, absence of human population immunity against chikungunya virus (CHIKV) might have supported virus amplification. However, formal proof of concept is lacking. This study determined the prevalence of anti-CHIKV IgG antibodies as well as CHIKV RNA shortly before the outbreak. Two hundred and six human sera were collected from patients with acute febrile illness in 2004/2005. Validated indirect immunofluorescence and real-time RT-PCR assays for dengue as well as CHIKV were employed. Laboratory evidence of dengue virus infection was seen in 67% of patients, indicating virus activity and exposure to Aedes spp. vectors. These vectors are the same as for chikungunya. However, no evidence of acute or previous chikungunya infection could be demonstrated in the same cohort. This study gives formal evidence that the absence of human population immunity correlated with a large chikungunya epidemic.
authors.affiliation: Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Panning
authors.forename: Dominic
authors.initials: D
authors.lastname: Wichmann
authors.forename: Klaus
authors.initials: K
authors.lastname: Grywna
authors.forename: Augustina
authors.initials: A
authors.lastname: Annan
authors.forename: Sriyal
authors.initials: S
authors.lastname: Wijesinghe
authors.forename: S A M
authors.initials: SA
authors.lastname: Kularatne
authors.forename: Christian
authors.initials: C
authors.lastname: Drosten
mesh_terms: D000293:Adolescent; D000328:Adult; D000330:Aedes / Q000821:virology; D000368:Aged; D018354:Alphavirus Infections / Q000097:blood / Q000453:epidemiology* / Q000276:immunology; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood* / Q000276:immunology; D002646:Chikungunya virus / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D015331:Cohort Studies; D003716:Dengue Virus / Q000276:immunology; D004196:Disease Outbreaks; D005260:Female; D005334:Fever / Q000821:virology; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007303:Insect Vectors / Q000821:virology; D008297:Male; D008875:Middle Aged; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013188:Sri Lanka / Q000453:epidemiology; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral