Epidemiology of Sindbis virus infections in Finland 1981-96: possible factors explaining a peculiar disease pattern.
Pogosta disease (PD), an epidemic rash-arthritis occurring in late summer is caused by Sindbis virus (SINV) and is transmitted to humans by mosquitoes. Altogether 2183 PD cases were serologically confirmed 1981-96 in Finland, with an annual incidence of 2.7/100000 (18 in the most endemic area of Northern Karelia). The annual average was 136 (varying from 1 to 1282) with epidemics occurring in August-September with a 7-year interval. Studies on 6320 patients with suspected rubella (1973-89) revealed 107 PD cases. The depth of snow cover and the temperature in May-July seemed to predict the number of cases. The morbidity was highest in 45- to 65-year-old females and lowest in children. Subclinical SINV infections were 17 times more common than the clinical ones. The SINV-antibody prevalence in fertile-age females was 0.6% in 1992; the estimated seroprevalence in Finland is about 2%. Among game animals the tetraonids (black grouse and capercaillie) had the highest seroprevalence (65%) in the epidemic year of 1981.
Brummer-Korvenkontio
M
M
Haartman Institute, Department of Virology, University of Helsinki, Finland.
Vapalahti
O
O
Kuusisto
P
P
Saikku
P
P
Manni
T
T
Koskela
P
P
Nygren
T
T
Brummer-Korvenkontio
H
H
Vaheri
A
A
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D018354:Alphavirus Infections / Q000097:blood / Q000453:epidemiology* / Q000209:etiology / Q000635:transmission; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D001717:Birds / Q000821:virology; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D005260:Female; D005387:Finland / Q000453:epidemiology; D005843:Geography; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D015994:Incidence; D007223:Infant; D018445:Infectious Disease Transmission, Vertical; D008297:Male; D008322:Mammals / Q000821:virology; D008875:Middle Aged; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000097:blood / Q000453:epidemiology* / Q000209:etiology; D012189:Retrospective Studies; D012621:Seasons; D016036:Seroepidemiologic Studies; D012737:Sex Factors; D012845:Sindbis Virus / Q000276:immunology* / Q000302:isolation & purification
D000914:Antibodies, Viral