[Preliminary evaluation of the Culicoides biting nuisance (Diptera: Ceratopogonidae) in the province of Boyacá, Colombia].
BACKGROUND
Inhabitants in the western border of Boyacá province have reported high nuisance levels and dermatologic problems caused by the intensely irritating bites of the very small flies of the genus Culicoides.


OBJECTIVE
A survey was carried out to locate the affected area, identify the anthropophylic Culicoides species and estimate its abundance in Boyacá.


METHODS
Nuisance reports and clinical records of dermatologic cases associated with Culicoides bites were requested from health authorities in counties where nuisance reports had been received or which had geographical features apparently favorable for Culicoides infestations. An outdoors entomological survey using human landing catches was undertaken in areas reporting a pest problem.


RESULTS
Culicoides infestations were confirmed as a serious nuisance problem in the rural areas of nine counties located in the western foothills of the Eastern Range of the Colombian Andes. Although available epidemiological records were fragmented, it was established that in six counties 11.4% of the dermatitis cases (total=2,472 cases) reported between 2003 and 2005 were attributed to the Culicoides bites. The entomological survey identified Culicoides pachymerus as the dominant species, 99.3% of 3,389 caught females. Biting rates in the most intensely affected areas reach a geometric mean of 52 females/person per 5 minutes. Multivariate analysis indicated that abundance of C. pachymerus had a negative relationship with altitude.


CONCLUSIONS
Based on its dominance and high biting rates, C. pachymerus is probably the species responsible for the high nuisance levels caused by Culicoides bites and the associated dermatological pathology, within the study area.
Santamaría
Erika
E
Grupo de Entomología, Instituto Nacional de Salud, Bogotá, D.C., Colombia. esantamaria@ins.gov.co
Cabrera
Olga Lucía
OL
Zipa
Yaneth
Y
Ferro
Cristina
C
Ahumada
Martha Liliana
ML
Pardo
Raúl Hernando
RH
D000531:Altitude; D000818:Animals; D002519:Ceratopogonidae / Q000033:anatomy & histology / Q000145:classification / Q000472:pathogenicity*; D003872:Dermatitis / Q000453:epidemiology / Q000209:etiology; D005260:Female; D006801:Humans; D007299:Insect Bites and Stings / Q000150:complications; D007300:Insect Control; D007303:Insect Vectors; D015999:Multivariate Analysis; D011634:Public Health