February 2018
From the State Vet's Office

An Ounce of Prevention: Verse Two

I looked back to see what subjects I addressed in this column last winter. I had written about the screwworm incident in Florida, the success of the Brucellosis Eradication program in Alabama and an article titled, "An Ounce of Prevention." That article was aimed at horse owners and encouraged them to vaccinate their horses in the spring.

At that particular time, we did not see the storm clouds gathering that would eventually land us in an outbreak of low pathogenic avian influenza. We were fortunate we only dealt with the low pathogenic form instead of the highly pathogenic form of the avian influenza virus.

When the dust finally settled, we looked back over our shoulders and asked if there was anything we could have done to prevent the outbreak. Probably not surprising, we found we had become complacent on our biosecurity practices. So, I decided to write about preventive measures we need to be taking NOW to prevent another avian influenza outbreak that could be, by the luck of the draw, either low or highly pathogenic.

I have often said that biosecurity is a relatively new term. It certainly wasn’t something we used when I was in veterinary school back in the 1980s. I found one source that said the term "biosecurity" was not widely used until the ’90s.

Of course, the fact you do not have a single word to describe something doesn’t mean it doesn’t exist. In fact, the original meaning of biosecurity was pretty broad. Biosecurity was defined as "measures put in place to prevent or reduce the risk of transmissible diseases." The best I can tell, they had some of those measures in place back in Old Testament times.

Biosecurity is extremely important in preventing viruses such as avian influenza, human flu or even the common cold. And a lot of what makes up biosecurity is just common sense. Remember when your mom used to say, "Get that out of your mouth. You don’t know where it’s been." I would tweak that just a little and say, "Don’t walk into that chicken house without disinfecting those shoes. You don’t know what you may have walked through."

I can remember when I was in private practice, I would occasionally see a dog with parvo that I am fairly certain had never been outside the fenced-in backyard. The owners always had a hard time understanding where the virus could have come from. I would always suggest that we never know what we are walking through.

Of course, we would know if we stepped in a pile of dog manure. But sometimes we just walk through somewhere that those invisible viruses are hiding and bring them home to our pets.

Hopefully, if you are a poultry grower or work in a closely related job, you will pay close attention to the rest of this article. I am sure nothing I am going to write will be some great revelation like Saul on the road to Damascus. Still, we become complacent and need to be reminded occasionally.

I heard a presentation once where the researcher put out disinfectant foot baths for people to walk through going into their chicken houses. To document the effectiveness of the foot baths, they set up video cameras and informed the farmworkers they were being videoed. Early on, the workers all walked through the disinfectant on their way into the chicken houses. After a couple of weeks, the video showed the workers would put one foot in the disinfectant and step over with the other. And after another couple of weeks, they were stepping over the disinfectant baths completely. And that was with people who knew they were being videotaped.

I want to mention a few practices that, if used as intended, can greatly reduce chances of spreading bird flu. If you don’t have a poultry farm, these practices could keep your dog from getting parvo. Or it could keep you from getting the flu.

The main thing we know is that avian influenza viruses do not just wander into chicken houses on their own. The viruses are typically introduced into the environment via wild waterfowl feces. Actually, it is usually ducks. Wild geese are fairly susceptible to the virus and they tend to die before they can shed much of the virus.

Last year from early March until April 21, we were extremely busy on our search-and-destroy mission to stop the spread of avian influenza in Alabama. When the dust settled, poultry company veterinarians, U.S. Department of Agriculture and state agriculture representatives got together and looked at why and how the virus likely spread. It was interesting that the expert opinion of the group was that direct farm-to-farm transmission played a limited role. That means there was reasonable risk the virus was introduced from the environment.

One of the significant concerns was the lack of strict biosecurity at poultry farms. I know poultry farms are interesting to people who are not familiar with them. We recommend you do not allow visitors in the poultry houses. Many of the commercial poultry companies have policies limiting admittance to poultry houses. After all, "You don’t know where those visitors have been."

Another practice – that may work as well or even better than anything else – is the use of footwear disinfectants to walk through when entering the chicken house. However, they are only effective if they are maintained and used.

I don’t mean to be critical – well, actually I do. I have seen foot baths with algae growing in them. I have seen foot baths that have not been changed in so long they looked like they were filled with muddy water.

Probably one of the easiest ways to spread the virus is on shoes worn in the pasture or woods where wild ducks have done their business. And probably one of the easiest ways to prevent that route of introduction of the virus is to have properly maintained and properly used foot-ware disinfectants.

We also recommend that you have some type of dedicated coveralls or outer covering only worn in the chicken house. Obviously, we are not doing surgery, so we are not trying to be sterile. We are just stacking the deck in our favor by covering clothes we wear outside the chicken house.

I have been to poultry farms with coveralls hanging in the control room, but they appear to have not been worn in quite a while.

We also believe the virus can be introduced onto a farm on tires. We have worked with various utility companies to try to educate them about driving onto poultry farms and to stay as far from the chicken houses as possible. They also know to reduce exposure to the farm as much as possible during known outbreaks.

And finally, like your momma told you, "Wash your hands." Wash your hands before going into the chicken house and wash them after you come out.

Use common sense. Don’t become complacent. Work with your poultry company and follow their biosecurity policies.

Usually, January through late spring is avian influenza season. If you follow this advice, maybe we can spend this year doing something besides fighting avian influenza.




Dr. Tony Frazier is the State Veterinarian for Alabama. You can contact him at 334-240-7253.