What We Need to Know About Bird Flu: A CAS Conversation
In this new series of CAS Conversations, we’re sitting down with students, faculty, staff, and alumni to dive into their unique insights, experiences, and ideas. From classroom innovations and personal stories to cutting-edge research and community impact, CAS Conversations offers fresh perspectives from the incredible people shaping our campus and beyond.
Bird flu, or avian influenza, has been making headlines as outbreaks continue to spread among wild and farmed birds across the United States. While human infections remain rare, the potential for the virus to mutate and pose a greater threat is keeping scientists on high alert. Between concerns about transmission, vaccine development, and public health precautions, understanding bird flu has never been more important.
In this CAS Conversation, we speak with virologist and º£½Ç»»ÆÞ biology professor Taisuke Izumi to break down everything we need to know about bird flu. From how the virus spreads to its risks for humans to ongoing efforts to prevent a major outbreak, Izumi provides us with valuable insight into this evolving public health issue.
PH: What exactly is bird flu, and how does it differ from other flu viruses we hear about?
TI: Bird flu, also known as avian influenza, is a respiratory virus that primarily infects birds. Unlike the seasonal flu, which circulates in humans every year, bird flu mainly spreads among wild and farmed birds. While human infections are rare, they can occur, usually through direct contact with infected birds.
PH: How does bird flu spread among birds and is there any risk to humans?
TI: Bird flu spreads when birds come into close contact with infected birds, their droppings, or contaminated water and surfaces. Wild birds can carry the virus without getting sick, but when it spreads to farmed chickens or ducks, it can cause serious illness.Ìý
While bird flu mainly affects birds, certain strains have infected other animals and humans, usually through direct exposure to sick birds. However, human-to-human transmission is extremely rare.Ìý
PH: How exactly could people contract bird flu? Ìý
TI: People can contract bird flu through direct contact with infected birds, their droppings, or contaminated surfaces, but not from eating properly cooked poultry or eggs. The virus is killed by heat, so as long as poultry is cooked to 165°F (74°C) and eggs are fully cooked, there is no risk, according to the CDC. Handling raw poultry or consuming undercooked eggs from an infected bird poses minimal risk, but everyone should always follow food safety guidelines.
PH: How widespread are the human cases—and how serious?ÌýÌý
TI: As of January 6, 2025, a total of 70 confirmed cases have been reported in the United States since 2024. Ìý
These cases are very rare and have primarily occurred among individuals who work closely with infected animals, such as poultry and dairy workers. While many cases have been mild, some have resulted in severe illness or, in rare instances, death. Notably, in January 2025, the first human death from bird flu in the US was reported in Louisiana. Currently, there is no evidence of sustained human-to-human transmission of bird flu.
PH: What precautions are in place to prevent a major outbreak?
TI: Governments and health organizations, such as the Centers for Disease Control and Prevention (CDC), closely monitor bird flu outbreaks to prevent major incidents. Farmers implement measures such as testing birds and culling infected flocks to halt virus spread. Recently, the US Department of Agriculture (USDA) granted a conditional license for an avian influenza vaccine developed by Zoetis to protect poultry from the virus. Health experts also monitor for any mutations in the virus that could increase its danger to humans.Ìý
While the seasonal flu vaccine does not directly protect against bird flu, getting vaccinated can reduce the risk of simultaneous infections, which could lead to more severe illness. Additionally, co-infection with both avian and human influenza viruses could, in theory, allow for genetic reassortment, potentially creating a new virus that spreads more easily between humans. Therefore, receiving the seasonal flu vaccine is a recommended. To minimize risk, it is essential to avoid contact with sick or dead birds.
PH: Is there a realistic chance of bird flu evolving in a way that poses a major threat to humans, or is that unlikely?
TI: While bird flu viruses can mutate and potentially become more infectious to humans, this has not yet occurred. Scientists closely monitor these viruses for mutations that could facilitate human-to-human transmission. Historically, the 1918 influenza pandemic, known as the Spanish flu, was caused by an avian-origin influenza A virus that adapted to humans, resulting in an estimated 50–100 million deaths worldwide. Currently, the risk of a similar pandemic remains low, but experts continue to study and prepare for any potential changes.
PH: What’s the most important thing the public should know about bird flu right now?
TI: Currently, the risk of bird flu to the general population is low, as the virus primarily affects birds. However, individuals who work closely with birds, such as farmers and poultry workers, should take extra precautions. It is essential to wear proper protective equipment (PPE), including masks, gloves, and gowns, when handling animals.Ìý
Following proper food safety practices, such as thoroughly cooking poultry to an internal temperature of at least 165°F and ensuring eggs are fully cooked, helps reduce potential health risks.Ìý
About Professor Taisuke Izumi
Professor Izumi is a researcher specializing in emerging infectious diseases, including HIV and SARS-CoV-2. His work focuses on understanding the persistence of these infections to develop an HIV functional cure strategy and treatments for the long-term effects of COVID-19. In addition, he investigates chronic herpesvirus infections, such as KSHV and EBV, under microgravity conditions using a unique cell culture device.