Location: Exotic & Emerging Avian Viral Diseases Research
Title: Infectivity and transmission in turkeys and chickens of low and highly pathogenic avian influenza viruses from the 2020 outbreak in turkey farms in North and South CarolinaAuthor
Pantin Jackwood, Mary | |
CRIADO, MIRIA - Orise Fellow | |
LEYSON, CHRISTINA - Orise Fellow | |
PARRIS, DARREN - Orise Fellow | |
YOUK, SONGSU - Orise Fellow | |
Deblois, Suzanne | |
Olivier, Timothy | |
Spackman, Erica | |
Suarez, David | |
Swayne, David |
Submitted to: American Association of Avian Pathologists
Publication Type: Abstract Only Publication Acceptance Date: 7/15/2020 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: In March 2020, an outbreak of H7N3 low pathogenicity avian influenza (LPAI) occurred in turkey farms affecting nine premises in North Carolina and one in South Carolina (SC). Highly pathogenic avian influenza (HPAI) was subsequently confirmed on a second turkey premise in SC showing increased mortality and respiratory signs. The outbreak was controlled through rapid depopulation of the affected flocks. Experimental studies were performed in turkeys and chickens to evaluate the infectivity, pathogenicity, and transmission of two of the LPAI viruses, one of them with a deletion in the neuraminidase gene, and the HPAI virus. Birds were inoculated intrachoanally with 102, 104, or 106 mean egg infectious doses (EID50) of the respective viruses and non-inoculated hatch mates were added to each dose group to examine transmission. High infectivity and transmission to all contacts was observed with the HPAI virus in turkeys. However, the virus dose required to infect the chickens was higher than the turkeys and the virus did not transmit to contacts. The clinical signs and mean death time for the HPAI virus were typical for HPAI viruses in gallinaceous species, with most infected birds dying by 3 days post inoculation. No disease was observed in turkeys and chickens exposed to the LPAI viruses. |