First finding of Dirofilaria repens in a natural population of Aedes albopictus.
The invasive mosquito Aedes albopictus (Skuse) (Diptera: Culicidae) has become widespread in Italy during the past decade. Also Italy has foci of canine filariasis caused by Dirofilaria (Spirurida: Onchocercidae), due to subcutaneous D. repens Railliet & Henry as well as the dog heartworm D. immitis (Leidy) transmitted by various vector mosquitoes (Diptera: Culicidae). In 2002, at Fiumicino, west of Rome (Lazio Region), 17% of dogs were found to have D. repens microfilariae in peripheral blood. To evaluate the role of Ae. albopictus as a vector of Dirofilaria in this area, female mosquitoes were collected daily, June-October 2002, landing on dog or human bait in a rural house at Focene. Mosquitoes were maintained at 27 degrees C and 70% RH for 6 days, to allow development or purging of filaria larvae, then identified and frozen for subsequent molecular assay with filaria-specific ribosomal S2-S16 primers. To distinguish specimens harbouring infective L3 Dirofilaria larvae, DNA was extracted separately from the mosquito abdomen and head-thorax. Dirofilaria species were identified by sequencing, confirmed by polymerase chain reaction of positive specimens using primers specific for D. immitis and D. repens. Dirofilaria DNA was detected in 3/154 (2%) of Ae. albopictus females examined: D. repens DNA in head-thorax and abdomen of one collected 27th July; D. immitis in the abdomen of one collected 24th September; DNA of both D. immitis and D. repens in the head-thorax of one collected 11th October 2002. Thus Ae. albopictus is a potential vector of both Dirofilarias in Italy, representing risks for veterinary and human health.
Cancrini
G
G
Parasitology Section, Department of Public Health Science, University of Rome 'La Sapienza', Rome, Italy.
Romi
R
R
Gabrielli
S
S
Toma
L
L
DI Paolo
M
M
Scaramozzino
P
P
D000330:Aedes / Q000469:parasitology*; D000818:Animals; D018509:DNA, Helminth / Q000235:genetics; D004182:Dirofilaria / Q000145:classification / Q000302:isolation & purification*; D004183:Dirofilaria immitis / Q000302:isolation & purification; D004184:Dirofilariasis / Q000635:transmission*; D004283:Dog Diseases / Q000635:transmission; D004285:Dogs; D005260:Female; D006801:Humans; D007303:Insect Vectors / Q000469:parasitology*; D007558:Italy; D008297:Male; D016133:Polymerase Chain Reaction / Q000379:methods; D011634:Public Health; D012621:Seasons; D013045:Species Specificity
D018509:DNA, Helminth