Lv J.,Shandong Agricultural University |
Lv J.,Sino German Cooperative Research Center for Zoonosis of Animal Origin |
Lv J.,Key Laboratory of Animal Biotechnology and Disease Control and Prevention of Shandong Province |
Lv J.,Tsinghua University |
And 38 more authors.
Virus Research | Year: 2012
This study aimed to determine the transmission characteristics of H9N2 avian influenza viruses (AIVs) derived from the air. Eight H9N2 AIVs were isolated from chicken houses between 2009 and 2010. We analyzed the phylogenic and pathogenic traits of these isolates. What is more, transmission characteristics in guinea pigs of two airborne isolates were determined in experimental conditions. Phylogenetic analyses indicated that the homologies of HA and NA genes of eight isolates were 95.4-99.7% and 86.6-99.8% respectively. They were able to duplicate in lung tissues of guinea pigs without prior adaptation. Two airborne isolates could both transmit among guinea pigs by direct contact. No infection was detected in aerosol contact animals while H9N2 AIV aerosols were detected in the air of isolators. Aerosol infection dose experiment showed that aerosol median infective dose (ID50) of H9N2 AIV to guinea pigs was 3.58×106copies, demonstrating that the aerosols could infect guinea pigs at certain concentrations in experimental condition. In conclusion, H9N2 AIV aerosols were infectious to mammals, suggesting that urgent attention will need to be paid to its transmission. © 2012 Elsevier B.V.
Liu D.,Shandong Agricultural University |
Chai T.,Shandong Agricultural University |
Xia X.,Institute of Military Veterinary PLA |
Gao Y.,Institute of Military Veterinary PLA |
And 7 more authors.
Science of the Total Environment | Year: 2012
There is a rather limited understanding concerning the antibiotic-resistance of the airborne S. aureus and the transmission of the antibiotic-resistant genes it carries Therefore, we isolated 149 S. aureus strains from the samples collected from the feces, the indoor air and the outdoor air of 6 chicken farms, and performed the research on them with 15 types of antibiotics and the REP-PCR trace identification. The 100% homologous strains were selected to conduct the research on the carrying and transmission status of the antibiotic-resistant genes. The results revealed that 5.37% strains (8/149) were resistant to methicillins (MRSA), and 94% strains (140/149) were resistant to compound sulfamethoxazole, etc. In addition, these strains displayed a resistance to multiple antibiotics (4, 5 or 6 types) and there were also 3 strains resistant to 9 antibiotics. It should be noted that the antibiotic-resistance of some strains isolated from the feces, the indoor and outdoor air was basically the same, and the strains with the same REP-PCR trace identification result carried the same type of antibiotic-resistant genes. The results showed that airborne transmission not only causes the spread of epidemic diseases but also exerts threats to the public health of a community. © 2012 Elsevier B.V.