April 24, 2015
Flu season is almost over for us humans, so if your flu shot kept you healthy this year, be grateful.
Unfortunately 7 million birds in the US haven’t been that lucky. That’s the number of dead or killed poultry due to bird flu on Midwest farms since March. This is not the same H5N1 virus that’s been responsible for bird flu outbreaks in Asia for the past decade. This is H5N2, a new combination spun off by the roulette wheel of Mother Nature as 15 “H” proteins and 9 “N” filter through the living systems of a multitude of birds and other susceptible creatures. Like, hmmm, us.
This particular virus has caused no human cases in the US. There is little imminent risk to humans as it will take significant changes of the viral particle for it to cause disease in us, however the fact is we have no idea when one of these bird flu iterations will make that leap into the human pool. What is clear is that all flu viruses that do infect humans—the ones we prudent citizens get vaccines against each year—start in birds. The largest flu pandemic ever recorded was the 1918 “Spanish” flu which likely began in the United States and took the lives of 50-100 million people around the world over the ensuing 3 years.
What can we do about it?
CDC has already collected “seed” viruses from this epidemic as potential stock for future vaccine. Considering how much the virus would still have to change to infect humans, it would be a colossal waste of money to manufacture a human vaccine at this point. Much like our flu shot this year missed the strain on one of the three components, flu vaccines only work when they’re very accurately targeted. So human prevention by vaccine is not an option for bird flu at this time, like it is for regular flu.
The dept of agriculture and CDC are on high alert with Midwest farmers to track and control the avian outbreaks through culling—mandatory killing—of infected or exposed poultry, and through stepped up efforts on sanitation. Despite these measures, the virus has continued to spread. No one yet knows how, but there can be no doubt that the extreme crowding of factory farming is ideal for transmission of this disease.
From experience in Asia we know that wild birds often carry avian flu over wide areas, spreading it through tiny rural farms as well as large urban areas. We also know that all types of flu are spread by close contact. Both of these vectors are likely responsible for the recent arrival of this strain.
We need to be doing research into better vaccine production methods. Current processes haven’t changed since they were invented and rely on the slow and unpredictable means of growing the organisms, which are then inactivated or killed prior to being made into vaccine. This method takes several months for each batch. It would take years to manufacture enough vaccine for a new flu. By then the number of worldwide deaths would dwarf the 1918 tragedy.
Pharmaceutical companies are not likely to take up this challenge; there is no money in it, at least not until there is a pandemic, and by then it will be too late. Government entities like NIH and CDC excel at research, but our less-is-less Congress has been parsimonious with funding.
While I am no fan of factory farming, even if we stopped totally today we still have the wild birds to contend with. But reducing or eliminating the close confines of livestock will slow the spread, and everything we can do to buy the birds more time, buys us more time to develop prevention and cure.
For the first time in history we are watching the gestation of the next virus likely to cause a pandemic. The virus must continue to alter itself through generations of folding and unfolding and rearranging those “H” and “N” proteins to be infectious and lethal to humans. We don’t know if that will take 1 year or 5, 20 or 50, but we do know it will come.
We must fund work on real-time vaccine technology, but we probably won’t. At least not until bird flu starts killing us. And when it does, we shouldn’t be surprised.