Intervention strategies to reduce the risk of zoonotic infection with avian influenza viruses: scientific basis, challenges and knowledge gaps

Abstract

A range of measures has been recommended and used for the control and prevention of avian influenza. These measures are based on the assessment of local epidemiological situations, field observations and other scientific information. Other non‐technical factors are (or in some cases should be) taken into account when developing and recommending control measures. The precise effects under field conditions of most individual interventions applied to control and prevent avian influenza have not been established or subjected to critical review, often because a number of measures are applied simultaneously without controls. In most cases, the combination of measures used results in control or elimination of the virus although there are some countries where this has not been the case. In others, especially those with low poultry density, it is not clear whether the link between the adoption of a set of measures and the subsequent control of the disease is causative. This article discusses the various measures recommended, with particular emphasis on stamping out and vaccination, examines how these measures assist in preventing zoonotic infections with avian influenza viruses and explores gaps in knowledge regarding their effectiveness.

Low risk of avian influenza A (H5N6) transmission to depopulation workers in Korea

“…3 Because poultry-human transmission of HPAI H5 is likely to occur by direct contact with infected poultry, 1,4,5 early detection and depopulation of infected poultry flocks are commonly used to control the spread of HPAI virus in poultry and to prevent human infections. 6 Starting November 20, 2016, poultry infections by HPAI (H5N6) virus were reported in Gyeonggi Province, Republic of Korea. A series of control measures, including depopulation, were rapidly implemented by the Korean Ministry of Agriculture, Food and Rural Affairs.…”

Protective Efficacy of Recombinant Turkey Herpes Virus (rHVT-H5) and Inactivated H5N1 Vaccines in Commercial Mulard Ducks against the Highly Pathogenic Avian Influenza (HPAI) H5N1 Clade 2.2.1 Virus

“…Prior to this event, Egypt’s poultry population has continued to be infected with the H5N1 virus with regular reports of human cases. To date, the following control measures have been implemented to mitigate the extent and impact of avian influenza H5N1: biosecurity, a ban on poultry movement, market rest days, stamping out, and vaccination [ 18 ]. Whereas the first four measures are perceived as the classical approach to the disease and have gained prominence worldwide, vaccination against avian influenza H5N1 is still hotly debated and its implementation is considered on a country-by-country basis only.…”

Biosecurity measures for backyard poultry in developing countries: a systematic review

“…China, Indonesia, Egypt or Vietnam) and massive culling whenever HPAI A/H5N1 is detected [114,115]. However, these interventions have been difficult to sustain [116].…”

“…In view of the mounting evidence that HPAI A/H5N1 can be transmitted through contaminated environments [119,120], we recommend that biosecurity measures, if appropriate, should be better promoted as a crucial intervention in containing H5N1 circulation. The international animal and public health community should encourage further research or projects to identify sustainable measures, which must be practical and proportionate to the risk [34,115]. In addition, we believe that the correct approach to zoonotic diseases should be holistic, based on the principle of improving personal and community hygiene to prevent all infectious diseases in backyard poultry to eventually mitigate exposure and transmission risk to humans.…”