Editorial: Pandemic Threat Minimization for Rochester, MN
01/25/2006
Paul Munnis
Even to the most casual observer who looks at the city of Rochester, MN, has a sense that there is a lot of Canadian Geese here. A peak estimated level of about 100,000 Canadian Geese now call Rochester home for several months of the year with an estimated 30,000 birds in permanent residency.
Rochester is located along a key migratory flyway for this species. We provide a comfortable habitat for them. This once nearly extinct species has made an amazing comeback as a result of excellent public stewardship. However they are reaching a pest level within our city and the problem is compounding.
While the birds are “cute,” and “interesting,” and “fun to feed” shelled corn to, they are also a health threat to the citizens of Rochester and the purpose of this piece is to opine on the nature of the threat and to dare to recommend a course of action to control this threat to human life in our city. If we get action going where there is now none then it is enough for us. Presently there is no visible city plan to deal with bird over population.
For example our children are playing soccer and football on the feces contaminated fields which are prime breeding grounds for bird pathogens. Each year thousands come to Silver Lake for fireworks and they sit on the feces contaminated grass. Just getting lime spread regularly onto these fields would be a darn good beginning.
The Nature of the Human Threat
As we understand things from our readings from the Center for Disease Control, we are no public health expert at all, there are three main threats to the public caused by the presence of Canadian Geese.
They are as follows:
• Avian Flu
• Normal Flu
• Pandemic
All three of these terms are related and with Avian Flu Pandemic as the source of our biggest overall threat to life.
We remind readers that flu emanates from birds. A “Pandemic” is defined as an outbreak so severe that it spreads rapidly (exponentially), and it kills at least 50% per hundred of those who are infected. There is no known immunization available to halt the spread of the Avian Flu. It differs from normal flu in that it is a viral and resistant strain that has mutated from birds and poultry to humans and is difficult to manage and resistant to most normal immune systems. Indeed it feeds upon a normal and healthy immune system killing robust and healthy people first. According to Dr. Michael Osterholm of the CDC and the U of M, people who are in the 18-40 age range are the most vulnerable to contracting Avian Flu as we now know it. These are the mothers and fathers of our children located right here in our community. With half of them gone we would face a post-pandemic crisis of enormous proportions. We therefore must act to reduce the threat of Avian Flu to our residents.
During a pandemic there is a breakdown of normal society caused by both acute illness and high death rates. We are not trying to scare people but the truth is that in today’s global economy, we depend upon just in time manufacturing, and we are highly dependent upon public sanitation, rapid distribution of goods, and essential services such as police, fire, health care, and the disposing of our dead in a sanitary manner. These subjects are dealt with elsewhere in the literature of pandemics but right now we are interested in threat reduction for our community members who are at risk from the large Canadian Goose population.
AVIAN FLU
Avian influenza (AI) is a disease found among poultry. AI viruses can infect chickens, turkeys, pheasants, quail, ducks, geese and guinea fowl as well as a wide variety of other birds, including migratory waterfowl. Each year, there is a flu season for birds just as there is for humans and, as with people, some forms of the flu are worse than others.
Of the three types of influenza virus, influenza type A infects and kills the greatest number of people each year and is the only type that causes pandemics. It originates in wild aquatic birds. The virus does not cause illness in these birds, and although it is widely transmitted among them, it does not undergo any significant genetic change.
AI viruses can be classified into low pathogenicity and highly pathogenic forms based on the severity of the illness they cause in poultry. Most AI strains are classified as low pathogenicity avian influenza (LPAI) and cause few clinical signs in infected birds. In contrast, high pathogenicity avian influenza (HPAI) causes a severe and extremely contagious illness and death among infected birds.
There are 144 different characterizations of the virus based on two groups of proteins found on the surface of the virus. One group is the hemagglutinin proteins (H), of which there are 16 different types (H1-H16); the other group is the neuraminidase proteins (N), of which there are 9 different types (N1-N9). The virus currently detected in several Asian and European countries is an H5N1 type of highly pathogenic (HPAI) virus.
Direct transmission from the birds to humans has not yet been demonstrated, but when a virus is transmitted from wild birds to domesticated birds such as chickens, it undergoes changes that allow it to infect humans, pigs, and potentially other mammals. Once in the lung cells of a mammalian host, the virus can “reassort,” or mix genes, with human influenza viruses that are also present. This process can lead to an entirely new viral strain, capable of sustained human-to-human transmission. If such a virus has not circulated in humans before, the entire population will be susceptible. If the virus has not circulated in the human population for a number of years, most people will lack residual immunity from previous infection.
Once the novel strain better adapts to humans and is easily transmitted from person to person, it is capable of causing a new pandemic. As the virus passes repeatedly from one human to the next, it eventually becomes less virulent and joins the other influenza viruses that circulate the globe each year. This cycle continues until another new influenza virus emerges from wild birds and the process begins again.
Some pandemics result in much higher rates of infection and death than others. Scientists now understand that this variation is a result of the genetic makeup of each specific virus and the presence of certain virulence factors. That is why the 1918-19 pandemic killed many more people than either the 1957-58 or the 1968-69 pandemic.
HOW FLU SPREADS
AI is primarily spread by direct contact between healthy birds and infected birds, and through indirect contact with contaminated equipment and materials. The virus is excreted through the feces of infected birds and through secretions from the nose, mouth and eyes.
Contact with infected fecal material is the most common of bird-to-bird transmission. Wild ducks often introduce low pathogencicity into domestic flocks raised on range or in open flight pens through fecal contamination. Within a poultry house, transfer of the HPAI virus between birds can also occur via airborne secretions. The spread of avian influenza between poultry premises almost always follows the movement of contaminated people and equipment. AI also can be found on the outer surfaces of egg shells. Transfer of eggs is a potential means of AI transmission. Airborne transmission of virus from farm to farm is highly unlikely under usual circumstances.
HPAI can be spread from birds to people as a result of extensive direct contact with infected birds. Broad concerns about public health relate to the potential for the virus to mutate, or change into a form that could spread from person to person. The U.S. Department of Health and Human Services is aggressively working to ensure public health is protected. More information about the joint efforts of the federal government is available at http://www.pandemicflu.gov/
WHAT CAN WE DO TO PROTECT OURSELVES?
First we need to avoid the “Bambi Syndrom,” wherein we are prevented from action by valid humane feelings towards the birds and instead concentrate on our own human survival and the public health. We must take a pragmatic view of human survival and that means sacrificing some of our bird flocks to assure the survival of some 50,000 residents of Rochester in a severe pandemic.
In a pandemic in a city of 100,000 people, some 50,000 people will die within 6-12 weeks of a severe pandemic outbreak if steps are not taken to control the outbreak and to contain the spread of the disease. We will not concentrate on the options that we can take to treat sick people or to circuit break the spread of the disease but rather we deal here with minimization and prevention of the threat to the resident humans.
That means that we have to cull the Canadian Goose population in our city. You cannot do it without impact to the Geese but here are some things that I think that we can do in order to be humane and efficient in this unpleasant task.
1. We can reduce our bird population by shooing them away. This is done by erecting spinning reflectors, such as can lids that rotate in the wind. The reflections arouse a sense of insecurity among the flocks and they thus shy away from contact. Another technique is to set up periodic cannon fire automatons that fire off dummy shot-gun charges every few minutes thus scattering the birds before they can feed. This method is used at airports where birds pose a threat to aircraft collisions but it is highly annoying in an urban area where it is not liked due to the continual noise pollution. For feeding areas in large open spaces it is a perfectly acceptable method of shooing away unwanted birds.
2. We can reduce our bird population by reducing their food supply. There is no big revelation here. Hungry poultry will look elsewhere for food.
3. We can destroy their eggs. The eggs of Canadian Geese can be squashed and broken thus preventing birth.
4. We can cull the flocks. There is no simple way to say this, culling is another term for killing off the existing bird flocks. We can do this in humane ways and the DNR can guide us in the methodology. We can do it by a quota system and up to a calculated threshold level of safety and we can increase this threshold at the first sign of danger to pandemic.
5. We can irradiate the culled carcasses, thus killing all known pathogens and salvaging the meat.
6. We can freeze the carcasses, thus adding to our emergency public food supply.
7. We can warehouse the frozen birds and dispense them to feed the hungry both in times of health and in time of starvation threat.
8. We can pass ordinances that protect other birds from contamination with a requirement that all commercial poultry and exotic rural area pets be isolated from flyway bird populations.
9. We can require that exotic birds be removed from urban areas. This is a form of ordinance.
10. We can empty our bird feeders and encourage our feathered friends to dine elsewhere.
11. We can clean up bird effluent and spread lime. Lime has a beneficial effect of killing bird related pathogens while sweetening the soil and protecting our ground water. A city wide effort at liming our soil is indicated at the first sign of spring and should be done immediately and then maintained with periodic applications.
12. We can establish an Avian crematory for infected birds. Burning the bird carcasses at high temperatures will aid the problem of infected bodies and hold down the spread of disease.
13. We can provide influenza preventatives to workers who are performing this work. An example is Tamiflu by Roesche and is known to be effective at reducing initial risk. This is the same medication that health care workers get in an emergency pandemic.
These 13 steps could help a great deal in prevention but we are far from organized as a City to make them happen.
SOME THINGS THAT WE CAN BUILD UPON
The State of Minnesota, Department of Natural Resources will provide permits for bird culling. The State DNR has already provided for this. We may need to license our City for participation in the program.
There are State and Federal funds available to us. We need to organize to obtain a rapid supply of these funds while they are still available.
Individuals can be encouraged to erect spinners, flashers, and shotgun automatons through a public information campaign. In a similar fashion people can be encouraged to empty their bird feeders.
Our city can place shotgun automatons at our city airport. There are Federal airport funds available for this and it should probably be done anyhow and activated only when indicated by rising threat levels.
We could set culling goals and threshold levels. For example: cull 500 birds per night from existing city populations and cull the flock to an 80% threshold level. That means that 80,000 birds per hundred thousand will need to be eliminated. At a rate of 500 birds per day that will require 160 days to reach the threshold level. This is period of five to six months of intensive culling activity. After that we would throttle back and perhaps extend use of the facilities to surrounding communities. Thus all of the spring, summer, and fall seasons of 2006 would be spent culling birds.
We should apply for federal funds to hire people to perform the culling and post-processing ASAP. We could then create culling teams and they could do culling at night, after the city retires. Added teams would be needed for striping the carcasses of feathers, gutting the poultry, plus irradiating and flash freezing and warehousing of the birds as well as disposal of remains such as feathers and intestines.
A likely location for the post culling facility could be the Rochester airport, a reasonably remote location of publicly owned land. An incinerator would be built there as well as an open pit disposal area.
Lime crews would spread lime in former culled locations around the city assuring rapid curing of bird droppings. A regular liming would be done in remaining bird habitat areas.
We could achieve and then maintain the 80% threshold as needed due to incoming birds, and breeding. Threshold levels could be adjusted as threat levels change.
We could recruit a food pantry such as Channel One Food Bank to maintain the inventory and to dispense the frozen birds in the event of widespread community hunger. This would consist of a frozen inventory of 80,000 birds per 100,000 flock and to dispense them in time of a city food emergency. With the flock of culled birds resulting from fly-ins and breeding made available to feed the present hungry people of our area we could provide needed relief to the hungry citizens of Rochester.
A bird flu sampling team could test a sample space of the daily culled flock to look for signs of pathogen and mutation. Again funds from Federal and State could be sought for establishing managing the cost of maintaining this team.
Samples are usually taken by swabbing the mucus that coats the throat of live birds, which does not harm the birds. With wild birds, a fecal sample can be taken instead. These samples go into sealed tubes and are taken to USDA-approved laboratories where a polymerase chain reaction (PCR) test is run. A PCR test is a rapid method of identifying the virus, typically producing results within 3 hours. If a sample from an area where avian influenza has not been previously detected tests positive on a rapid test, an additional confirmatory test is performed. This test involves growing the sample in embryonated chicken eggs, which then provides the material to allow detailed identification of the strain of virus and whether it is HPAI (high pathogenicity) or LPAI (low pathogenicity). This test can take 3-5 days to produce results.
These actions are the minimum steps we can take to protect the public heath of the citizens of our community. There is no Santa Claus in this matter and we must act to protect ourselves. Community action and leadership is called for.
We encourage our city and County government leaders to organize to make these preventivie steps happen and to harness government to leadership in minimizing the threats of Avian Flu in Rochester. We believe that time is of the essence and we note that a pandemic could break out tonight, right here in Rochester, MN. Let’s get ready for it.