TY @Duck Drover
for your added insight and I sympathize with your approach for natural resistance but I can't wholeheartedly agree that breeders who vaccinate for Marek's do it because they've had outbreak but rather I believe most do it as a preventative and/or to meet customer demand for Marek's vaccinations just as hatcheries offer the same option. I have considered your perspective and thought it was a good point until I lost a non-vaccinated Marek's survivor to later adult complications and had a non-vaccinated juvenile shipped to me w/Marek's that my vet had to put down 2 weeks after receiving shipment of her - the breeder of her was gung-ho about not vaccinating for Marek's and raising natural resistance stock and where did it get me? -- an infected bird from their ark. From my point of view I prefer a vaccinated chick/juvenile. It's only luck that has kept my oldest non-vaccinated hen from contracting it. I keep a varied and nutritious diet for my birds and take them to the vet and have at least one yearly fecal done for each bird. Sorry, but after my experiences, Marek's vaccination is still my personal choice. Hopefully your CON perspective and my PRO perspective for Marek's vaccination gives readers food for thought.
Since you already had a confirmed case and you don't sell birds or let them leave your property for any reason, it makes sense for you to have vaccinated birds. It just means your property is infected and every bird you have is infected so if you were to not able to keep a bird in your isolated yard, it would need to be destroyed rather than sold or given away to infect another flock (or many). Once you vaccinate, you have to quarantine your birds for life and use biosecurity measures to confine all feather dander to keep it from spreading. A simple trip to the feed store after touching your birds could result in spreading the disease to countless other flocks without ever knowing you were the reason for so many deaths.
There are people selling vaccinated birds from infected flocks and those people have contributed to the spread of the disease with countless fatalities as a result if their unethical choices. When you vaccinate you have to quarantine birds for life and you would ethically need to disclose that your property is infected if you were to sell your home. I would personally prefer to lose my own flock than to potentially contribute to the spread of a deadly disease but that is the basis of my morals and not everyone has the same moral standards that I do. Some people are more about protecting their own birds than caring about the wellbeing of other people's birds so that has contributed to the disease being so widespread.
As long as the vaccine is available for purchase, it will continue to wipe out massive numbers of birds due to the symptomatic carrier effect. Not everyone understands how the vaccine is different than most vaccines as it spreads the disease rather than helping control it from spreading.
Anyone wanting a healthy flock and disease-free property would need to take steps to eliminate the disease or have naturally resistant birds rather than using vaccinated birds to allow the disease to spread without symptoms. Stress makes birds more prone to contracting diseases so anytime a bird's regular routine is disrupted it can make that bird more vulnerable to disease on the new property. Changing homes is very stressful for birds so that is why it is so important to keep 2 or more together and to quarantine in a new environment. If you bring in a non-vaccinated bird and it gets sick, the disease is most likely on your property and not the property where the bird originated from if there is no sign of the disease in the original non-vaccinated flock.
We hatch our own birds so they only leave our property with no new birds coming onto our property. Since we have ducks, which are carriers of chicken diseases because they are asymptomatic carriers, it is critical for our birds to show symptoms if any of the chickens were to pick up a chicken disease. I do not want to spread chicken diseases through asymptomatic carrier ducks so I have to know there are no signs of illness rather than masking symptoms that would allow the disease to spread.
Fortunately good care has kept our birds healthy and that has helped them build a natural immunity to disease. If that were to ever change, we would have to eat all our birds as a means of the destruction of our flock and we would have to start over by hatching eggs to make sure the chicks are not vaccinated and we do not bring in disease through asymptomatic carrier birds.
This is a topic I feel strongly about so I tend to speak up as a means of educating new bird owners who may be unaware of the dangers of having vaccinated birds. Most people should not vaccinate because it does more harm than good in the long run but there are people who would not have any success with chickens due to the high level of infection that they are already dealing with on their property.
