H5N1, also known as bird flu, is a highly contagious infectious disease that was originally discovered in birds. Today, H5N1 has claimed the lives of more than 300 million birds worldwide, according to UN health officers. However, this worldwide infection is becoming increasingly local.
Cases of bird flu in Pennsylvania have rampantly increased in the past few years. While there has been a total of around 14.6 million birds infected since 2022, around half of these infections occurred in 2026. In fact, as of April 10, Pennsylvania is the state with the most reported cases of bird flu, with over 923,560 birds infected in the last 30 days.
These cases, however, are not limited to birds. As science teacher Mr. Timothy Styer explains, outbreaks are present in other species too, including many mammalian species.
“Bird flu is not hopping through only a single mammal population, which is the path most flus take, through typical mammals like pigs, cows, and sheep,” Styer said. “This one has found its way into almost every mammal species that they’re testing, like raccoons, deer, and, now, housecats, meaning this virus is trespassing into where we live.”
While H5N1 has not developed a mutation that can lead to person-to-person contraction of the disease, the strain is rapidly evolving. As the disease mutates and changes its protein structure, it builds new variants that can impact more animals.
“This virus is looking for the opportunity to go through mutations and change,” Styer said. “And, when it hits that magic Yahtzee toss of getting that protein, bird flu will be contracted person-to-person.”
Styer explains that this mutation is more and more likely to occur.
“[Bird flu] can’t transfer to humans through the air yet — capital Y-E-T,” Styer said. “But, the more time it spends in mammal populations, the more likely it is to hit that lottery mutation, and then it’s going to be recognized around our noses, eyes, and/or ears.”
While no humans have transmitted the virus to other humans, there have still been reported bird flu cases in humans. While in most cases birds transmit bird flu to humans through high-dose exposure to a high viral load (i.e. large number of virus particles), this pattern is beginning to shift.
“In recent cases, people have [contracted the virus] by working with dairy cows,” Styer said. “It’s scary because it’s not necessarily the viral load that you would get when you handle a bird, so that would show that the viral load for transmission was dropping, which is a bad sign.”
Additionally, the mortality rate of bird flu is very high in humans.
“The death rate for the people who have gotten it from birds and cows is almost 60-70%, which is insane,” Styer said.
Given the rapid influx and severity of cases, it is necessary that humans, too, make progress in combatting the outbreaks.
“We need to have surveillance out there in the animal world, swabbing, testing and watching. We need to be sequencing these proteins to see how close they are to what they’re recognizing,” Styer said.
However, the current administration’s budget cuts in scientific research funding have dramatically decreased researchers’ ability to keep up with the accelerating pace of H5N1.
“When you want to find something in science, dump a lot of money into it, and then the research can get completed. They were able to do this during COVID, by targeting money towards the COVID vaccine, so we learned a lot real quickly,” Styer said.
H5N1 is a type of influenza virus, which puts researchers at an advantage, given that there is a lot of readily available information about influenza viruses already in existence. Unlike COVID-19, which was completely new, there is a strong foundation. But, if research does not continue, it will threaten emergency preparedness.
There is a current mRNA vaccine for H5N1, however, given that the virus is currently mutating, the vaccine must be updated, which will lengthen the process of manufacturing and developing a proper vaccine.
“And, if we’re relying on the old fashioned way, it’s going to take at least nine months to a year before you have enough with the vaccine to get out there to just health workers, so we’re going to lose a lot of people,” Styer said.
Bell & Evans, a family-owned American poultry company in Pennsylvania, notes that there are measures that the poultry industry is taking to combat the infection. This includes consistent disinfection and taking measures to bolster poultry immunity.
Having a foundational understanding of how and why diseases, like H5N1, develop and mutate is crucial for students to better understand the world.
“I think it’s important to understand why pandemics happen because, at the end of the day, they are something that humans face, so you have to know what they entail,” junior Rheya Singh said.
Pandemics are cyclical and, relatively, happen around every 20 years, so looking back at the past can help us prepare for the future.
“I mean, why do we study history? It’s because we don’t want to repeat the same mistakes that happened in the past,” Styer said.
