AU West Nile Virus
by Tommy E. Erskine
For those of you who may not have heard about it, there is a potential threat to our pigeon racing—pigeon keeping and raising, in fact, that arose out of the blue along the Atlantic seaboard, and it may possibly spread further, to other regions. To date, however, there has not been any instance of this disease being detected in other places in the U.S.—in particular, the Southeastern U.S. and along the Gulf Coast.
The West Nile Virus is a disease that is carried by mosquitoes. Indeed, worldwide, 43 different species can carry it. It had never been detected in the United States before late last summer (actually, August, 1999). At that time, veterinarians at zoos in New York had noticed that some of their captive birds were dying. At the same time, people were reporting finding other dead birds—thousands of crows—in New York, Connecticut, Rhode Island, New Jersey and later, in Maryland. In New Jersey, some racing pigeons were reported as acting “odd” and after a check, it was found that they had antibodies to the West Nile Virus. In New York and New Jersey, some horses were found to have the disease and many of them were subsequently “put down.”
Having antibodies does not mean an animal (or a human) has had a particular disease. It only means that they have been exposed to the virus or bacteria that causes the disease and that their immune systems developed the specific cells to fight it off. Having antibodies does not mean, either, that the animal or person cannot get the disease if exposed to it again—they may not be immune, even if they have been exposed and do have antibodies.
Dying birds and horses is one thing, but soon, people were reporting to emergency rooms with mild, flu-like symptoms, and even though the illness did not seem to be so severe, it was reported (and confirmed) that six people died—and this, of course, was very serious. Unfortunately, there is currently no vaccine available against the West Nile Virus for man or animal.
Immediately, everyone was trying to determine in their own way what was happening, how this developed and where it came from. And then, some very creative medical detective work revealed that the same virus that was killing crows and infecting horses was responsible for causing the illness being seen in some humans, so the U.S. Centers for Disease Control (CDC) was notified, and an alert about the virus was issued.
Most state agricultural agencies were notified and local health departments where the virus was suspected to be active started monitoring reports of dead birds or incidents of birds acting unusual. They set up testing for suspected birds and found that 17 species of birds tested positive for antibodies to it or actually carried the virus. Unfortunately, they found that some pigeons showed antibodies to the virus. In New Jersey, where the racing pigeon fanciers had been working with the state veterinarians, the pigeon racing community was asked to stop shipping birds until the first killing frost. Rightly or wrongly, they had associated racing pigeons with migratory species of birds.
In other parts of the world, migratory birds have been implicated in the spread of the West Nile Virus. It was suggested that if that were the case here, stopping the movement (shipping) of any birds across state lines might hinder any movement of the virus. In other words, if there were any chance that racing pigeons could carry the disease, this could help halt the spread. One veterinarian commented that as far as their contributing to the spread of WNV as a migrating species, stopping the shipping of racing pigeons was no more a factor than one cup of water contributed to the salinity (or freshness) of the water in the Atlantic Ocean.
This may be an apt analogy, and the birds probably do not contribute to the virus’ spread, but no one knew for sure at the time. And, nevertheless, as we would expect, our racing pigeon clubs were more than happy to assist state authorities and one New Jersey club called off release of at least one futurity race. As luck would have it, by the weekend after the State’s announcement and request, a cold night along the East Coast had provided the natural chill needed to kill off the mosquitoes—or send them into their winter’s hibernation. The race did get off on the weekend it was supposed to, albeit a day late.
The West Nile Virus is related to several other diseases that are caused by arboviruses or flaviviruses—Kunjin, St. Louis Encephalitis, Japan B and Murray Valley Fever are all related to it. It is an arthropod-borne virus—mosquitoes, ticks, spiders, lice, or other insects in the family of arthropods—insects with segmented bodies and jointed legs. Insects in this order also have bodies with shells that are made up of chitin (very much like shrimp have and they moult their shells, again, like shrimp).
WNV is spread by mosquitoes. And, you must be bitten by an infected mosquito to be exposed to it. Exposure to the virus can cause a form of encephalitis that begins with mild, flu-like symptoms, but it can develop into something far worse. Some people, and some animals, are very sensitive to the virus and the potential encephalitis, and it can cause death! Please take note that humans cannot catch West Nile Virus from handling a bird or touching a person or a horse that has it, or that has been exposed to it. It is believed that mosquitoes are the most common vector—again, you must be bitten by a mosquito that is carrying the virus in order to be exposed to the virus. Many outbreaks of West Nile and related viruses occur in isolated pockets—the virus can pop up for a season, then disappear, leaving a bewildered population trying to figure out how and why. This could well be the case with West Nile Virus here in the United States—we may never see it again—or it could recur and expand to take in more victims and a wider area this next Spring.
After the initial outbreak, and over the winter of 1999-2000 the Centers for Disease Control and many state and local departments of agriculture put their laboratories and staffs on alert and began testing different birds and animals for antibodies or exposure to the pathogen that causes the West Nile Virus. The CDC in Fort Collins, Colorado, the USGS Wildlife Research Lab in Wisconsin, the U.S. Department of Agriculture Research Lab at Plum Island in New York, and numerous other agencies set up research programs and put in place networks to monitor the movement of birds, reports of dead birds and any other cases of West Nile Virus—in horses, crows, in pigeons or in humans. The focus of all this effort, of course, is to monitor any report of the virus and keep track of any potential for a recurrence of the disease resulting from the movement of any bird species this spring.
These authorities also want to keep track of mosquito populations this spring, test and monitor them for any appearance of the virus early in the season—to see if the virus wintered over in the hibernating insects. They will also want to test wildlife and captive animals for the presence of the virus, to see if perhaps it wintered over within any particular species. In this way, if the virus does appear again, we may have a step up on it and can move to develop a defense strategy. Much of this may seem like conjecture and “What if?” But everyone is working to be ready, in case WNV shows up again. One strategy may be to implement more stringent programs to abate mosquito populations in the Atlantic seaboard area. Regardless, with widespread monitoring, if the virus should appear in the Gulf Coast or Southeastern U.S. we will know immediately and may be able to intervene and abate the problem there.
What has the pigeon community done during this whole affair? The AU certainly has not set on the sidelines and watched things roll by. The two national racing pigeon organizations have agreed to work with authorities on ANY level to assist or advise them on any matter pertaining to our racing birds. The AU has taken a very proactive role in monitoring the situation and making sure that those agencies involved know of its interest and its willingness to assist them.
On learning that racing pigeons (among other animals) may be in the cycle of the transmission of the disease, the American Racing Pigeon Union, Inc. contacted Centers for Disease Control and state, local and private officials to let them know that our members and Board of Directors stand ready to do whatever they need to assist them in their efforts. The AU immediately set about to establish a West Nile Virus Strike Force to contact whomever was necessary to monitor any information on the virus and closely analyze any reports—positive or negative—with respect to racing pigeons. This Committee, headed by Bob Phillips, is actively keeping in contact with a multitude of agencies, maintaining an active effort to collect, analyze and disseminate any information on the virus and our birds, and working to get reliable information about West Nile Virus and any developments related to it to the pigeon fancy in general, as quickly as possible.
The exact role that our racing pigeons may play in the West Nile Virus cycle is not clear at this time. First, there are really so few racing birds compared to wild pigeons and doves, and their movements are controlled and very restricted, as a rule, unlike the wild flocks. It does appear, in fact, that the virus is not viable in pigeons for more than a few days—meaning that even if a mosquito bit an infected pigeon, it may not pick up enough virus from the bird’s blood to transmit it to another animal—be it bird or human.
There is no documented evidence of any symptoms that pigeons exhibit when or if they have or are carrying West Nile Virus, so any suggestion that that this “mysterious” disease has afflicted any particular bird, flock or loft is total conjecture at this stage.
One point that is worth repeating, though, and that is that you cannot get West Nile Virus from a pigeon...or a dog...or a cat—a mosquito that is actively carrying the virus must get a blood meal from you—not just bite you.
At the time of this report, the CDC was doing a study on pigeons with West Nile Virus, to observe symptoms, reactions and other things with the birds. There are ongoing experiments being done with WNV in many other labs across the country, too. Various animals are being exposed and infected and their reaction to the virus is being monitored and recorded.
While no one knows how the West Nile Virus jumped the Atlantic or Pacific Oceans and appeared here in the United States, this outbreak has proven to be a wake-up call for everyone involved—we are not isolated from these things by what have been our own natural geographical barriers. And some scientists believe the appearance of the virus is just another manifestation of the effects of global warming—these mosquitoes need a more tropical climate—or at least a warmer climate—rather than the typically temperate climate found in the Atlantic seaboard region of the U.S. Global warming and La Nina has shifted weather patterns and migration paths of birds have shifted accordingly.
And many people in the poultry industry are watching the outcome of these experiments very closely, although experiments carried out in other countries have shown that chickens and turkeys cannot get the disease without the mosquito vector. This again suggests that the best prevention may be simple mosquito control—netting, insecticides and pool and puddle abatement—getting rid of old tires, old cans and bottles full of water, or drain any place with standing water.
Our members must also be very careful to make sure that anything negative relating pigeons to West Nile Virus in the press, on radio or on television gets corrected as quickly as possible. This is not an easy effort. Every day, more detailed, very technical reports appear—and more will become available in the near future. Each report has to be gone through line by line and analyzed in light of what impact, if any, it may have on our sport and hobby—but it is critical that we not let the media get half the story and give the public the wrong impression via television and the printed press—in the event these false reports start, we must be very active and immediately get the truth out.
Although the West Nile Virus has never been seen before in this hemisphere, it is a serious problem, because it is potentially deadly to man. It is a challenge that the pigeon racing community must meet head on—and we must do all we can to assist our government in its effort to learn more about his disease. The government is working to monitor this spring, and we would ask that if you are approached to provide information, birds or give them access to your loft and race teams, please do so.
It serves all our interests to watch this threat very closely and be ready to do whatever our neighbors need us to do.