Zombies, treemen, werewolves are fictional characters. Do you believe that? These names may seem to be straight out of films and books, but they find mention in some unusual diseases.    

Here we have listed some of the rare diseases that primarily happens to one in a million.

Cotard’s Delusion aka Walking Corpse Syndrome

Cotard’s Delusion is an extremely rare mental illness in which the patient genuinely believes that he/she is missing a body part or is actually dead. They tend not to eat, bathe or mostly prefer to spend time alone or in cemeteries, among the deceased.

This disorder is connected to the dysfunction in the certain area of the brain that is responsible for recognising and associating emotions. This causes emotional detachment and removes the sense of personal identity when looking at the body.

Fibrodysplasia Ossificans Progressiva aka Stone Man Syndrome

Fibrodysplasia ossificans progressiva (FOP) is a genetic disorder that turns the soft tissues of the body in bone over a time period. The gene ACVR1 that is found in bone, muscle, ligaments and tendons regulates the growth of these tissues and is responsible for turning cartilage into bone as a child grows.

Mutation in this gene lets ossification to go unchecked throughout the patient's life. This dysfunction occurs in one in two million people and currently, there is no remedy present to counteract this disorder.


Elephantiasis is a hindrance of the lymphatic vessel which leads to extreme swelling of skin and tissues, mainly in the leg and testicle area. This condition can be attributed to various causes, though the mosquito-borne parasite is the most well-known condition. Over 40 million people are affected by this disorder.  

There are medications that can kill the parasite, but early intervention is much needed for a better cure.

Hypertrichosis aka Werewolf Syndrome

Generally, women thread their eyebrows and wax body hairs as a part of a beauty routine and hygiene measures. But there are some who have abnormal hair growth covering every inch of their body, including the face which can be completely covered in long hairs. These people suffer from hypertrichosis disorder and due to the abnormal amount of hair, it is nicknamed as werewolf syndrome.

Hypertrichosis can be either acquired or congenital. In both cases, several genetic mutations lead to abnormal growth. Still, there is no proper reason listed behind this mutation.

The remedy contains traditional methods of hair removal or laser treatment but the results are not long lasting.