Virus spread pattern within infected chicken farms using regression model: the 2003-2004 HPAI epidemic in the Republic of Korea

• Published in: Journal of veterinary medicine. Series B Vol. 52; no. 10; pp. 428 - 431
• Main Authors: Yoon, H, Park, C.K, Nam, H.M, Wee, S.H
• Format: Journal Article
• Language: English
• Published: Berlin, Germany Blackwell Verlag GmbH 01.12.2005; Blackwell Publishing Ltd
• Subjects: Animal Husbandry - methods; Animals; avian influenza; Avian influenza virus; Chickens; disease models; disease outbreaks; Disease Outbreaks - statistics & numerical data; Disease Outbreaks - veterinary; Epidemics; epidemiological studies; epidemiology; farms; Female; highly pathogenic avian influenza outbreak; Influenza A virus; Influenza in Birds - epidemiology; Influenza in Birds - mortality; Influenza in Birds - transmission; Korea - epidemiology; Male; Poultry; Poultry Diseases - epidemiology; Poultry Diseases - mortality; Poultry Diseases - transmission; Regression Analysis; Sex Factors; Statistical analysis; virus transmission; Viruses; South Korea; Korea
• ISSN: 0931-1793; 1863-1959; 1439-0450; 1863-2378
• DOI: 10.1111/j.1439-0450.2005.00891.x

During the 2003-2004 epidemic in Korea, the infection time and within-farm spread pattern of virus were analysed for the highly pathogenic avian influenza (HPAI) outbreak on chicken farms using regression models based on epidemiological data. Mortality observed on a given day had a positive linear association with time after initial infection. HPAI spread more rapidly on farms managed by employees and on farms with larger numbers of chicken houses in use. The disease spread more rapidly among layer chickens than among broilers. Using statistical model, we found that farmers recognize the abnormally high mortality resulting from HPAI approximately 5 days after infection. Without any intervention, entire flocks would die within 12 days of introduction of the HPAI virus to the infected farm.