ATLANTA — Poultry producers know well the devastating effects that highly pathogenic avian influenza has had on poultry flocks. With the species jumps in the virus, it can be found in dairy cattle, various wild birds and waterfowl, domestic cats, and several other birds and mammals. The virus has, thankfully, not been a great threat to humans in the United States, but what effects can it potentially have on infected humans?
The Centers for Disease Control and Prevention note in a recent report that influenza type A virus can cause gastrointestinal symptoms in people, as well as infect mammal species through means that are non-traditional and non-respiratory.
Seasonal flu viruses impact people through the respiratory tract and cause respiratory symptoms. The CDC report notes that researchers have looked at how often people infected with seasonal flu and new strains of flu have reported gastrointestinal symptoms.
CDC adds that the H5N1 virus has been found in raw milk, and people should avoid consumption of this product, as well as other mammals like cats and dogs have consumed virus-contaminated products and it has led to infection and even death. But for humans the risk of contracting symptoms from ingesting H5N1 infected meat and milk products is low, “but theoretically possible,” CDC said.
“Researchers summarized data from reports that showed dogs and cats that ingested (H5N1) virus-containing material (typically eating virus-contaminated meat or drinking virus-contaminated milk) could develop a potentially severe and fatal infection,” the report notes. “Numerous animal studies also have shown that eating (H5N1) virus-contaminated meat or drinking (H5N1) virus-contaminated milk can lead to infection and death in some mammals. However, there are limitations in translating these findings to people.”
For human digestive issues, CDC researchers looked at human flu cases where people complained of severe GI tract ailments to gain a better understanding of how flu viruses impact this system and found that seasonal and novel type A influenza can cause GI tract symptoms in people according to clinical reports.
“Additional studies found different influenza A virus subtypes are able to multiply within human GI tissues in laboratory settings, suggesting influenza A virus infection in the human GI tract may be possible,” the report said. “However, it is also important to note that laboratory settings do not have the same acidic conditions as the human GI tract, which may inactivate these viruses.”
The CDC adds that it will continue to research how flus like HPAI impact the human gastrointestinal system, and if this poses a non-respiratory means of infection for humans and mammals. For safety, the department notes to avoid consuming raw milk and to cook all meat products to the appropriate temperature.
“Cooking poultry, eggs and beef to the appropriate internal temperature kills bacteria and viruses, including avian influenza A viruses,” CDC said. “Choosing pasteurized milk and products made with pasteurized milk is an important way to keep you and your family safe. Pasteurization kills bacteria and viruses, like avian influenza A viruses in milk. Make the best decision for your health and the health of your family by always choosing pasteurized milk and products made with it.”
