Animals and humans suffer from different diseases

One of the reasons that animal experiments fail is that all different animals suffer from different illnesses.  For example, humans suffer from around 30,000 illnesses, but less than 1½ % are seen in any other animal (Page, Dr T, 'Vivisection Unveiled', p6).  This problem means that often the first stage in developing an animal model is to try to recereat some o the symptoms which the human may suffer from.  This isn;t the same as there will be biological differences.


Examples of illnesses which are specific to humans include the following:


  • Cancer in humans is almost always in the lining membranes – like the lungs.  Although animals like mice and rats do get cancer, it’s in their bone and connective tissue.  Theirs is a sarcoma, ours is a carcinoma.  Two different terms for different illnesses (World Medicine, Nov 3 1979, p79).
  • Cystic Fibrosis is a human illness which kills patients at a young age.  95% of human deaths linked to this are caused by excessive fluid on the lungs. For years animal experimenters were claiming they had an animal model, the genetically altered CF- mouse.  This rodent model was incomplete, as the fluid-filled lungs never occurred(Snouwaert,J N. Brigham,KK et al. 1992. Science. vol 257. pp1083-1088).  This is because the glands which cause the terrible problem of excessive fluid in humans (the serous glands) don’t exist in rodents. (Hospital update 1994 Jan)
  • An animal experimenter working on asthma, Dr K F Chung, admitted “animal models have fallen short of reproducing the human disease, particularly in mimicking the spontaneous and persistent airflow obstruction that characterises asthma.” (K F Chung 'Usefulness of animal models in asthma research' European Respiratory Review1995, 5:29 p184)
  • HIV affects only humans, and despite giving enormous doses to monkeys, they have resisted developing AIDS and we still have no animal model for the killer condition (Institute of Medicine 'Mobilizing Against AIDS, 1986, DeVite, Hellman, Rosenberg, 'AIDS Etiology, Diagosis, Treatment and Prevention', 1992).
  • Attempts to create heart disease in animals have failed as none developed artery plaque as humans do (Gross D, 'Animal Models in Cardiovascular Research', 1985).  Attempts to induce heart disease in animals have been made in all the best known species of lab animals and extended into species as diverse as pelicans, sealions, ducks, parrots and bears.  All have failed. (Gross D, 'Animal Models in Cardiovascular Research', 1985)


Attempts are made to recreate the diseases, or some of the symptoms, but this isn't the same. For example, dogs have pacemakers attached to them which increase the heart rate and induce heart attacks, which is very different from a human having a heart attack.  But even if it was possible to give an animal exactly the same illness as a human has, scientifically accurate experiments on animals would still be impossible because animal react differently to medications.



Over 700 treatments have been found to be effective in animal models of stroke.

Effective in human patients:  0

30 vaccines protect against HIV in primates.

Effective in human patients: 0

22 drugs have been developed in animals which treat spinal cord damage effectively.

Effective in human patients: 0

More than 100 treatments prevent diabetes in the NOD mouse model.

Effective in human patients: 0


"God knows we've cured mice of all sorts of tumours…But that isn't medical research." [Thomas E Wagner, cancer research specialist.]


'Lab mice...have responded quite well to an experimental Alzheimer's vaccine...Lab rats with paralyzing spinal-cord injuries have walked again...And we've cured cancer in enough rodents to fill several New York City subway systems. For people, however, there is no cure for spinal-cord injury, Alzheimer's, Parkinson's disease, multiple sclerosis, cystic fibrosis, osteoporosis, brain and other cancers...the list goes on....
Despite the truckloads of promising ideas spilling out of molecular and cellular biology, the dearth of researchers qualified to do patient research means that few discoveries turn into treatments, cures or preventions'.


(Sharon Begley, 'Research lags due to few physician-scientists', Wall Street Journal, 25 April 2003).

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