A recent outbreak of highly pathogenic avian influenza in commercial chickens and ducks in South Korea has health officials in the country on high alert and some poultry farmers taking quarantine measures.
Health officials in South Korea have raised the bird flu alert status in their country to its second highest level, after identifying new outbreaks on poultry farms since confirming their first cases last week.
On November 18, South Korea’s Ministry of Agriculture, Food and Rural Affairs confirmed their first outbreak of highly pathogenic H5N6 avian influenza at two poultry farms. The announcement came after the virus had been found earlier in feces samples collected from migratory birds. In the first outbreak, officials culled more than 62,000 birds to prevent the spread of the virus. Since then, surveillance efforts have discovered the presence of H5N6 at two duck farms and one chicken farm in the country, and subsequently, the health ministry has culled an additional 30,500 birds. Officials have raised their alert level from “caution” to “alert” and have also taken the precaution of banning the movement of poultry from any farms within 10 kilometers of a reported outbreak, while considering more stringent preventive quarantine measures.
Avian influenzas are Type A forms of the virus that occur naturally in wild aquatic and migratory birds around the world. While wild birds can carry bird flu in their intestines and respiratory tracts without getting sick or showing flu symptoms, the saliva, nasal secretions, and feces of infected birds are highly contagious and can spread the virus to domestic chickens, turkeys, and ducks. Low pathogenic avian influenza (LPAI) viruses in infected poultry can cause mild symptoms such as ruffled feathers and a decrease in egg production or no symptoms at all. North American LPAI H5N1 influenza has been regularly detected in wild birds over recent decades with sporadic incidents in commercial poultry. Highly pathogenic avian influenza (HPAI) viruses, such as the current outbreak in South Korea, are much more serious and can cause severe disease and high mortality. According to the United States Department of Agriculture (USDA), HPAI cases in wild birds, captive wild birds, backyard poultry, or commercial poultry have been found in Arkansas, California, Iowa, Idaho, Kansas, Minnesota, Missouri, Montana, North Dakota, Nevada, Oregon, Utah, South Dakota, Washington, Wisconsin and Wyoming since December 2014.
The Centers for Disease Control and Prevention (CDC) notes that bird flu does not typically pose a health threat for humans and these cases are rare. However, humans can acquire the avian viruses through contact with saliva, mucus, or feces of infected birds to eyes, nose, mouth, or by inhalation. LPAI strains are not a health concern for humans and are considered to cause milder symptoms such as conjunctivitis, influenza-like illness, and lower respiratory disease which can lead to hospitalization. HPAI viruses in humans can lead to similar but at times more severe symptoms such as severe respiratory disease, multi-organ disease, and seizures. People who have been in contact with infected birds or areas where birds have been are most likely to be exposed to avian influenza, and can pick up the virus by breathing in infected droplets in the air or touching surfaces and then touching their mouth, eyes, or nose.
CDC officials state that the best way to prevent bird flu infections is to avoid exposure to potentially infected poultry. Individuals who come in contact with wild or domestic birds that might have avian influenza are encouraged to wear personal protective equipment and practice proper hand hygiene. For those who do get infected with bird flu, antiviral drugs typically given for human flu cases may be effective in treating the illness.