Although COVID-19 is perhaps the most pressing public health issue in the minds of the general public today, other diseases do not stop proliferating as a result. One cogent example of this is the current outbreak of avian influenza sweeping the globe.
At first, avian influenza may not register in the minds of the average person, as it only predominantly affects birds. It is a highly contagious virus that, according to the CDC, is spread through the saliva, feces and nasal secretions of birds. It also has a shockingly high mortality rate of over 60 percent, and the USDA reports that it has caused the deaths of over 22 million birds in our current outbreak, through a combination of the disease’s own fatality and the culling of infected birds in a bid to stop its spread. As sad as these statistics are, it can sometimes be hard to see why and how this affects human beings. In fact, the implications of this disease have dire consequences for the future of public health and our scientific understanding of diseases.
First, despite what the name suggests, avian influenza does not only affect birds. Although birds are the species most affected, it is reported to infect humans as well, mostly farmers and those who handle raw poultry. In humans, it manifests as a respiratory illness, and though there have not been very many cases of it, one article from the Center of Excellence in Clinical Virology in Thailand shows that it has a very high mortality rate of approximately 60 percent in humans. The disease has not yet evolved to such a position where human-to-human transmission is easy, so outbreaks in humans have remained fairly limited in scope. However, the virus is only a mutation or two away from being able to effectively do so.
Second, birds carry an incredible importance to our lives. Chickens, which are widely consumed across the globe, are particularly affected by the disease, with the CDC reporting a mortality rate between 90 and 100 percent. Generally, birds have fluid populations and migrate frequently across borders, which exponentially increases the rate of transmission between species. This makes it all too easy for the virus to be transmitted to chicken populations raised on open farms. Beyond chickens are also the eggs that they produce. As a result of the current bird flu outbreak, CNN Business reports that the price of eggs has skyrocketed, with some regions of the country showing an almost 100 percent increase in price. Even beyond the obvious use that chickens and the eggs that they produce have to us, the latter are used to manufacture vaccines. Although this technology may become obsolete with the rise of mRNA vaccine technology, which was used with some COVID-19 vaccinations, many vaccinations, including the flu vaccine, are still manufactured using eggs as a key ingredient. A specific virus strain is injected and allowed to incubate inside of a chicken egg, and is then harvested and inactivated to be used in a vaccine. If chicken populations were to decrease as a result of this outbreak and eggs were no longer available, this would prevent safe manufacturing of flu vaccines, which, according to the CDC, are estimated to save up to 7.5 million flu-related illnesses, and 6,300 flu-related deaths per year. In fact, according to CNN Health, the United States government has secret farms all over the country where chickens are raised in sterile isolation to prevent them from being exposed to a variety of pathogens, including avian influenza, in the case that a healthy population is ever needed for large-scale manufacture of vaccines.
Thus, though we are not the main targets of avian influenza, it affects our lives in many different ways. It is therefore extremely important to understand how it works and attempt to find solutions for it.
Additionally, avian influenza boasts a distinct evolutionary advantage, which is mostly responsible for it being so contagious and deadly within birds. First, avian influenza is used as an umbrella term for a variety of strains of the disease. Influenza viruses mutate extremely easily, and can, therefore, shift to their evolutionary advantage quickly. This is the same reason that humans need to get a flu shot of their own every year; it is a unique formula every time, created by scientists in anticipation of the predominant flu strain of the year. When the extremely malleable avian influenza is allowed to proliferate and spread within populations easily, this provides the perfect conditions for it to mutate as a response to its environment. This may then lead it to gain immunological strength against measures that may have previously kept it at bay. This is another reason why the prospect of avian influenza is so scary; as it is constantly shifting in bird populations, it may very easily mutate to become something that is better suited against the human immune system. Given its high degree of contagiousness, this would pose an extreme threat to the human population. The COVID-19 pandemic has already shown us that the world remains vastly underprepared for the rise of a novel pathogen, and avian influenza would prove no exception. Thus, it is imperative that scientists monitor the progression of avian influenza and study it carefully so that there is a stronger knowledge base to confront it if it crosses the species barrier.
Avian influenza is most deadly for birds, but it also has pervasive effects on human health and economy. This, combined with its potential to mutate into a disease for humans, should ring alarm bells. The scientific community must characterize this disease, and make it a top public health priority, so that animals and humans are protected against possible outbreaks.