Opujolevidnami viruses

For a long time sarcoma virus chickens was only known by a virus which causes the appearance of the tumor. Much later were discovered other similar viruses.
In 1933 shop found in wild rabbits caught in Kansas, rich cutaneous warty growths - papilloma. If healthy rabbits rubbed into skin mashed gruel of these papillomas, they 20-30 days appeared the same papillomavirus, and thus the disease was transferred from a sick animal on healthy unlimited number of times. On further examination, it was discovered that the cell papillomas contain special virus that causes this disease, and HPV can be transmitted from one animal to another by leachate, which contains a virus, but does not contain cells. When the rabbits that had papillomavirus, was under surveillance for a long time, it was discovered that on the place of papillomas in 10-18 months appears cancer, which progressively increases, it spreads quickly and causes the animal to death. This was of great interest not only to academics studying the nature of the cancer, but also for clinicians. The fact that some tumors man pass through the same stages as papilloma rabbits. For example, larynx cancer, and bladder cancer begins with small warts - papillomas, which only many years later turn into cancer.
So, not only sarcoma chickens, so similar to human tumors caused by a virus, but papilloma rabbits, very similar to the tumor person. So, sarcoma of the CSD is not the exception to the rule? But maybe papilloma rabbits - another exception to the rule? The study made a lot of new questions. When this papilloma began to study in detail, found one mysterious circumstance. A virus that is easily distinguished from papillomas were not found to have arisen from papilloma cancerous tissue. Rubbing the fabric in the skin healthy rabbit never led to the formation of papillomas. Where did the virus disappeared from the tumor? Special studies have shown that the virus has not disappeared, but he lost his boleznennostew, their ability to lead a healthy rabbit education papillomas. Such viruses, devoid of virulence, called "masked".
What happens to the virus when it is "disguise"? It's a mystery, which was partially allow only recently.
If papilloma rabbits attracted the attention of researchers in the stage of cancer, no one would know that this disease is caused by a virus. May be, and other tumors are investigated when the viruses they are "masked" and cannot therefore be detected?
All these issues have to be solved only with relevant experiences. But we had another scan those tumors in which they were not yet discovered.
This work persistently carried out for many years. The various species of animals have been discovered tumor caused by viruses. Currently known tumors insects, fish, reptiles, birds, mammals, which certainly caused by viruses. From all these tumors viruses that can cause these tumors in relevant animal. The existence opujolevidnami viruses became apparent to all researchers.

  • Cancer and milk