Environmental contamination by Aspergillus spp. in laying hen farms and associated health risks for farm workers

Abstract

Data on the occurrence and epidemiology of Aspergillus spp. in laying hens farms are scant. With the aims of determining levels of airborne contamination in laying hen farms and evaluating the potential risk of infection for workers and animals, 57 air samples from 19 sheds (Group I), 69 from faeces (Group II), 19 from poultry feedstuffs (Group III) and 60 from three anatomical sites (i.e. nostrils, pharynx, ears) of 20 farm workers (Group IV) were cultured. The Aspergillus spp. prevalence in samples ranged from 31.6 % (Group III) to 55.5 % (Group IV), whereas the highest conidia concentration was retrieved in Group II (1.2¾10 4 c.f.u. g "1) and in Group III (1.9¾10 3 c.f.u. g "1). The mean concentration of airborne Aspergillus spp. conidia was 70 c.f.u. m "3 with Aspergillus fumigatus (27.3 %) being the most frequently detected species, followed by Aspergillus flavus (6.3 %). These Aspergillus spp. were also isolated from human nostrils (40 %) and ears (35 %) (P,0.05) (Group IV). No clinical aspergillosis was diagnosed in hens. The results demonstrate a relationship between the environmental contamination in hen farms and presence of Aspergillus spp. on animals and humans. Even if the concentration of airborne Aspergillus spp. conidia (i.e. 70 c.f.u. m "3) herein detected does not trigger clinical disease in hens, it causes human colonization. Correct management of hen farms is necessary to control environmental contamination by Aspergillus spp., and could lead to a significant reduction of animal and human colonization.

Diagnostic Procedures and Available Techniques for the Diagnosis of Aspergillosis in Birds

“…15,16,[31][32][33][34][35] Air sampling methods and microsatellite typing have been used successfully for fungal identification. 30,33, [36][37][38][39] Differences in susceptibility of various avian species to aspergillosis have been expected by different authors based on the prevalence of aspergillosis.…”

Wind-Mediated Spread of Low-Pathogenic Avian Influenza Virus into the Environment during Outbreaks at Commercial Poultry Farms

“…One of the routes for pathogen transmission is through dispersal into outdoor air. Viruses may be dispersed as single particles or by using other particles (particulate matter) as a vehicle [ 9 – 11 ]. Recently, Ypma et al estimated that wind direction could explain about 18% of the total transmission of avian influenza between farms during an outbreak of influenza A(H7N7) virus in 2003 [ 12 ].…”

Species Distribution and In Vitro Azole Susceptibility of Aspergillus Section Nigri Isolates from Clinical and Environmental Settings

“…Fourteen isolates were from the respiratory tract of squirrels (Callosciurus finlaysonii; Basilicata, Southern Italy) trapped during a campaign to control allochthonous wildlife populations (13). Twelve isolates were from the environment of laying hen farms (14). All animal and human cases of probable/possible invasive aspergillosis (IA) were defined according to the criteria of the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/ MSG) (15).…”