There is quite a lot of media attention to “Bird Flu”. Is it something that we need to worry about?
SHOULD WE BE SCARED?
Normally I would say no, but today I say Yes.
In the 1918 Spanish Flu epidemic, healthy people in their 20’s got sick in the morning, and many were dead by the evening. Vaccines had yet to be discovered. And viruses are not susceptible to drugs like antibiotics (which work only against bacteria, a completely different form of life than viruses). We do have some treatments to reduce fever and treat symptoms, and we do have some very limited-use anti-viral agents like Tamiflu, but we DO NOT have effective pharmaceutical treatments for Influenza.
The current Influenza virus circulating in poultry and cattle in this country, dubbed “Bird Flu”, is an Influenza virus characterized as H5N1. This means that the “H” protein comes from a family of “H” proteins, designated “5”. This DOES NOT refer to its toxicity, infectivity or strength; it is only means that it is similar to other “H” proteins in a group that we call “5”. The “N” protein, likewise, is related to other “N” proteins in the group we call “1”.
Since 2003, 50% of humans infected with H5N1 Influenza have died. This is a serious disease.
Is this a serious disease? YES
- Should we be worried that it will begin to infect humans? YES
- How soon? We can’t be sure, but research suggests that a single mutation could allow human-to-human transmission, and the virus is very infectious. And if we do not isolate those points of early transmission, the viral infection will spread rapidly and beyond our ability to contain it.
- Would current vaccines help? MODERATELY, but YES
- Should I get the current flu vaccine? ABSOLUTELY YES. YES. YES.
- Will there be vaccines for this particular strain? YES
- Should I get it? ABSOLUTELY
- When will it be available? There are currently 2 vaccines for bird flu being tested in limited quantities, but they have not been approved by the FDA.
Truly specific vaccines for the human-to-human transmission virus cannot be developed until the infective strain actually emerges and it can be isolated and characterized. However, and I don’t know this to be true, it should be possible to use the NIH studies that have identified the potential mutation that would be able to create a human-to-human viral pathogen, as a model to prepare a potential vaccine in advance of that mutation occurring. - If some people do not get it, will I still be safe if I am vaccinated? YOU WILL BE SAFER THAN THOSE NOT VACCINATED, BUT YOU WILL STILL BE ABLE TO BE INFECTED.
- Will current politics affect an epidemic? If the new administration agrees to limiting vaccines, does not adopt an aggressive vaccination campaign or chooses to allow the infection to “run its course” and provide “natural immunity”, we will see millions of deaths in this country.
Below is some information on these points.
BACKGROUND
First, almost every single “Flu” comes from birds. The reservoir of influenza virus circulates in the waterfowl in Northern China. New strains periodically escape that reservoir and infect humans. Sometimes those strains simply infect the local population and do not spread. This is because the virus, although able to infect humans upon direct contact with the infected bird, is not able to be transferred from the infected human to another human. Direct contact with birds can provide large enough amounts of virus to infect a human, but the amount of virus in the sneezes or saliva from those people is insufficient to infect other humans.
WHAT DOES H5N1 MEAN?
There are two proteins on the surface of the virus, “H” and “N”, hence the designation H5N1. The “H” is the protein that attaches the virus to the cells in the respiratory tract and the “N” is the protein that AFTER attachment allows the virus to get inside the cell. After it enters the cell, the RNA of the virus produces proteins that replicate the virus. After those new viruses are made, they break out of the cell to infect other cells and, eventually other people.
It is the “H” protein that needs to be able to “recognize” (bind to) specific proteins on the surface of respiratory cells to allow the virus to infect you. Now, when a protein attaches to another protein, the strength of that attachment is on a spectrum from weak to strong.
You can think of a child trying to hold onto a basketball as opposed to Michael Jordan holding the basketball. Both hands have the structure to hold the ball, but the small hands on the child make it very difficult to hold the ball, while Michael Jordan’s hands are so large that they wrap around the ball. On the other hand, if there are enough children using their hands together, they are able to also hold the ball with the same strength as one Michael Jordan. This is the way proteins bind to other proteins.
Right now, the “H” protein on the Bird Flu virus strongly binds to the cells in birds and cows, but not so well to humans. A human who gets enough of the virus with the weak “H” protein can still get infected, but the virus shed from that person will not be strong enough to bind to the cells in another person.
But…these viruses are constantly mutating. That means that when the virus reproduces, the RNA (the genetic material of the virus), which is duplicated, can contain “errors”. When this happens, one of the beads in the RNA strand gets exchanged for a different bead. Each group of three RNA beads codes for one single amino acid in the protein chain of the “H” protein. So, changing one bead in that 3 bead code results in a new “H” protein that is just a little bit different from the one in the parent virus. Sometimes these new “H” proteins can no longer bind to the proteins on the respiratory cells of the host animal (bird or cow), and the virus simply dies out because it cannot infect. Sometimes the new “H” protein is pretty much the same and nothing changes. But, sometimes, the new “H” protein is different enough that it is able to bind more strongly to a human receptor protein on the respiratory cell, and if that increased strength is sufficient, then the virus shed from the infected human can now infect other humans. That is what we call human-to-human transmission.
Some recent studies in labs that study how mutations can change the activity of proteins have shown that it is possible that only ONE single mutation in the “H” protein may be enough to result in human-to-human transmission.
By the way, this research, which is called “gain-of-function”, is critical in understanding what mutations (changes) in a virus can lead to human-human transmission. When we understand what changes will result in this transmission, we can look for a viruses in the population with those changes and if we find it in some people, we can isolate them and better control the spread of the virus. This is incredibly important research, and at least in my opinion, would be irresponsible to prohibit. Gain-of-function research in China ahead of the COVID-19 pandemic, was critical research to have been done in order to find out how a COVID virus could change to be able to make human-to-human transmission possible. It is basic research into understanding viral spread and IS NOT military research for creating bioweapons.
WHAT SHOULD WE DO?
Get vaccinated. As soon as the industry gears up, there will be a vaccine for this Influenza variant. GET IT. This is you best protection against the virus. Although it will not necessarily prevent you from getting infected, it will absolutely reduce any symptoms and dramatically reduce any risk of serious infection that will require hospitalization or a fatal infection. Some people may still die, but the numbers will be miniscule compared to non-vaccinated individuals.
- Even before specific vaccines are available, get the current vaccine. Protection against the “N” protein will reduce the mortality of infection; protection against other “H” 5 proteins will reduce the mortality of infection.
DO NOT wait for the “best” vaccine. Delaying vaccination can make you susceptible to a dangerous infection. - Avoid raw milk. Pasteurization kills any virus in milk. Dairy cows can pass the virus through their milk.
- Avoid contact with dead birds. If you see one, do not try to remove it; contact local services to remove the bird.
POLITICAL ISSUES
There is a lot of discussion these days concerning vaccination and infection. The following is my personal opinion.
Vaccines are NOT DANGEROUS. Nothing is 100% safe, but the risk of an adverse event to a vaccine are miniscule compared to the risks associated with the diseases.
- Vaccines have eliminated Smallpox, Polio, Measles, Mumps, etc. Those under 90 will not remember the devastation caused by these diseases prior to vaccines.
- Vaccination needs to be on a massive scale.
In order to prevent large numbers of deaths from this virus when it mutates to allow for human-to-human transmission, we need to reduce the probability of individual exposure to virus. The only way to do this is to attempt to prevent the virus from getting near you. Vaccination of the vast majority of Americans as quickly as possible is the ONLY way to do this.
If people are vaccinated, far fewer will get infected and far fewer of the people infected will transmit the virus to others.
But, you may ask, why should I get vaccinated if you are already vaccinated? Aren’t you safe?
NO! Vaccines are only around 75% effective in preventing infection. So, you may still be in the group that can get infected. And the ability to reduce lethality is also not 100%.
Finally, the more people infected, the greater the ability of the virus to mutate. This is simple mathematics. Viruses are not “smart”. They do not “try” to change. But their reproductive engines make mistakes. These mistakes occur at a fixed, measurable rate. The more times a virus replicates, the more likely a mutation will occur. Even though most mutations are either lethal to the virus itself, or neutral to its infectivity or lethality, a small percentage lead to increased infectivity, and increased infectivity means that it will take over the “market” simply by being faster to infect other people. The only way to slow mutations is to lower the number of replications that the virus makes, and this can only be done by lowering the number of people who are infected.