The Shadow
CHARLOTTESVILLE, Va. (VR) – Doctors at the University of Virginia are sounding the alarm over three emerging viral threats they say could reshape the infectious-disease landscape in the United States if left unchecked: Avian influenza (H5N1), the Oropouche virus, and mpox, formerly known as monkeypox.
Infectious disease specialists say a combination of climate change, closer contact between humans and animals, and increased international travel is creating ideal conditions for these viruses to spread into new regions, including Virginia and the broader United States.
Avian influenza H5N1, widely known as bird flu, has long been a concern in poultry and wild birds. But experts warn that recent developments, including spillover into cattle and several cow-to-human infections, show the virus is evolving in ways that could eventually make human-to-human transmission possible.
The outbreak in birds began in the United States in early 2022 and is now in its fourth year, causing major disruptions in the poultry industry and contributing to higher prices for eggs and other poultry products at grocery stores.
In chickens, H5N1 can kill nearly all of an infected flock, often within 24 to 48 hours, and has been detected in commercial and backyard birds across almost every state. The virus is spread through contact with infected wild waterfowl, shared environments, and contaminated feces. It thrives in cold weather, with cases ebbing in the summer and surging again in fall, winter, and spring. Doctors say that one of the most worrisome trends is the virus’s ability to infect a growing range of mammals, including minks, foxes, cats, and, most recently, dairy cows, expanding the opportunities for the virus to adapt to humans.
While sustained human-to-human transmission has not yet been documented, the Centers for Disease Control and Prevention are closely monitoring farm workers and others with repeated exposure to animals. Scientists are also studying whether existing flu vaccines offer much protection or whether separate, specialized vaccines will be required.
“This virus is out there, continually interacting with people and mammals,” UVA experts note in the briefing, adding that its ability to mutate means the risk profile can change at any time.
The Oropouche virus, historically confined to the Amazon basin, is another infection now drawing scrutiny from physicians. Transmitted primarily by tiny biting midges so small they are often called “no-see-ums,” and some mosquitoes, Oropouche causes high fever, severe headache, muscle pain, and joint pain, and can relapse in up to 60% of patients after apparent recovery.
Once considered a rare, localized illness, Oropouche has spread across much of South and Central America and the Caribbean in recent years. Countries reporting cases now include Brazil, Peru, Panama, Colombia, Ecuador, Bolivia, and, more recently, Cuba and Haiti.
What alarms experts is that the species of biting midge capable of carrying the virus is already present in the southeastern United States, including Virginia. That means there is “no real barrier” to the virus eventually establishing local transmission if it is introduced by travelers or other means, they warn.
There is no vaccine and no specific treatment for Oropouche virus disease. While most patients recover, a portion develop neuroinvasive disease, with confusion, severe headache, and other neurological symptoms. Some require hospitalization, and though deaths are rare, the virus can strain health systems during large outbreaks.
Complicating matters, doctors say Oropouche often mimics other tropical illnesses such as dengue, Zika, chikungunya, and even malaria, making it easy to misdiagnose and underreport. That “silent spread,” UVA experts caution, can allow outbreaks to build unnoticed until they are widespread. Mpox is not the newest virus, but its recent global spread is new. Once seen mainly in parts of Central and West Africa, mpox has, since 2022, appeared in more than one hundred countries, including the United States, the United Kingdom, and nations across Europe, Asia, and Latin America.
The virus, related to smallpox, typically begins with flu-like symptoms, including fever, chills, headache, muscle aches, and fatigue. Swollen lymph nodes are a hallmark sign, followed by a distinctive rash that can last two to four weeks.
The virus’s recent outbreak was largely driven by a strain known as clade II, which has a relatively low fatality rate but spreads efficiently from person to person through close contact, including skin-to-skin contact and shared bedding or clothing.
Since 2024, however, more severe Clade I infections have been rising in Central Africa. More concerning to U.S. health officials, several cases, including patients with no travel history to Africa, have been reported in the United States since 2023. A vaccine originally developed for smallpox offers protection against mpox, and most patients recover without specific antiviral treatment. Still, health organizations stress that the virus’s ability to move rapidly across borders and into new networks is a reminder of how quickly localized outbreaks can become global.
In their overview, physicians and groups such as the World Health Organization and the CDC frame these viruses as part of a larger shift in infectious-disease risk, driven by human behavior and environmental change. Warming temperatures expand the habitat of mosquitoes and midges. Deforestation and agriculture increase contact between humans and wildlife, and international travel allows infections to hop continents in hours.
They also point to additional concerns, including chikungunya, measles resurgences tied to falling vaccination rates, and the potential for setbacks in virus control. If global health funding falters, as signs of a strained public-health system facing multiple, simultaneous threats. Experts emphasize that humans, animals, and the environment are “deeply interconnected,” arguing that constant surveillance, robust vaccination programs, and ongoing development of diagnostics and treatments are essential not only for known diseases but for future ones that have yet to emerge.
For now, avian influenza, Oropouche virus, and mpox are still somewhat under control, but if the warning signs aren’t closely monitored, that will change. Preparations must be made before the next major outbreak happens.
