Human outbreak of St. Louis encephalitis detected in Argentina, 2005.
BACKGROUND
An outbreak of flavivirus encephalitis occurred in 2005 in Córdoba province, Argentina.


OBJECTIVE
To characterize the epidemiologic and clinical features of that outbreak and provide the serologic results that identified St. Louis encephalitis virus (SLEV) as the etiologic agent.


METHODS
From January to May 2005, patients with symptoms of encephalitis, meningitis, or fever with severe headache were evaluated and an etiologic diagnosis achieved by detection of flavivirus-specific antibody sera and cerebrospinal fluid.


RESULTS
The epidemic curve of 47 cases showed an explosive outbreak starting in January 2005 with one peak in mid-February and a second peak in mid-March; the epidemic ended in May. Cases occurred predominantly among persons 60 years and older. Nine deaths were reported. SLEV antibodies, when detected in 47 patients studied, had a pattern characteristic of a primary SLEV infection.


CONCLUSIONS
Even though isolated cases of St. Louis encephalitis have been reported in Argentina, this is the first description of a large SLEV encephalitis outbreak in Argentina.
Spinsanti
Lorena I
LI
Instituto de Virologia "Dr José María Vanella", Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Enfermera Gordillo Gomez s/n, 5016 Córdoba, Argentina. contigia@cmefcm.uncor.edu
Díaz
Luis A
LA
Glatstein
Nora
N
Arselán
Sergio
S
Morales
María A
MA
Farías
Adrián A
AA
Fabbri
Cintia
C
Aguilar
Juán J
JJ
Ré
Viviana
V
Frías
María
M
Almirón
Walter R
WR
Hunsperger
Elizabeth
E
Siirin
Marina
M
Da Rosa
Amelia Travassos
AT
Tesh
Robert B
RB
Enría
Delia
D
Contigiani
Marta
M
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000097:blood / Q000134:cerebrospinal fluid; D001118:Argentina / Q000453:epidemiology; D002648:Child; D004196:Disease Outbreaks; D004665:Encephalitis Virus, St. Louis / Q000302:isolation & purification; D004674:Encephalitis, St. Louis / Q000175:diagnosis / Q000453:epidemiology* / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012621:Seasons; D012698:Serologic Tests
D000914:Antibodies, Viral