5. Typhoid Fever
In 1976, a medical journal published an article stating that patients who had typhoid fever emitted a smell that resembled freshly baked bread. Although smelling like a bakery may sound pleasant, typhoid is anything but.
Typhoid fever is a bacterial infection caused by Salmonella typhi that can range from mild to severe. Symptoms can include gradual fevers, weakness, abdominal pain, constipation, and a rose-colored skin rash. While typhoid is not very common in developed countries, it is prevalent in areas with poor sanitation and hygiene. The disease is treatable with antibiotics, but some strains have become resistant.
Narcolepsy is a disease that causes people to fall asleep at any given moment. People who have narcolepsy can experience symptoms like sleepiness, hallucinations, sleep paralysis, cataplexy, and a loss of motor control when overstimulated. Although these symptoms sound specific to narcolepsy, people can go years without receiving a proper diagnosis of narcolepsy.
Narcolepsy is caused by a loss of hypocretin, a brain chemical that derives from the hypothalamus and works in the brain as an alert system that keeps us awake and regulates sleep. Like migraines, narcolepsy can also emit a special odor.
A study found dogs are able to smell the odor and warn patients up to five minutes before an attack, allowing people to get to a safe location, sit or lie down, or take other precautions. Dogs can also be trained to place themselves in front of patients so they can fall on the dog rather than on the floor. Currently, it is unknown exactly what causes the compound in odor change.
3. Bacterial Infections
Pseudomonas aeruginosa is a bacterium that causes several types of infections in humans. The bacteria produce a blue-green color and are common among those with diabetes, cystic fibrosis, burn patients, and drug users. Considered an opportunistic bacteria, as infections occur after preexisting diseases or conditions, Pseudomonas can be present if you have had hot tub folliculitis.
There are two distinct ways to identify Pseudomonas: in a laboratory and its odor. It possesses a grape-like odor that is produced by a compound identified as 2-aminoacetophenone. Although there is no official way to identify Pseudomonas, 2-aminoacetophenone may prove to be very useful for identification, as it is present early in the growth cycle.Related: 10 Diseases That May Show Up on Your Skin
In the 1960s, nurses from a mental hospital began commenting on a peculiar odor emitting from the back of the hospital. Researchers began investigating the potential cause for the smell and thought it to be schizophrenia. The smell was described as “skunk-like” and remained on patients even after bathing, especially in those with catatonia.
A study done on schizophrenia patients’ sweat showed that a panel of human odor testers, as well as trained rats, could sense the unknown odor in the sweat of schizophrenia patients. Years later, the compound was identified as trans-3-methyl-2-hecenoic acid.
This was a major discovery, as a physical link to a mental illness was now able to be identified. However, other researchers were unable to identify or confirm the link. In 2005, a team of researchers found that it was a global variation in body odor that may be unique to those with schizophrenia rather than a single compound.
1. Parkinson’s Disease
Joy Milne, a retired nurse, was convinced her husband Lee was emitting a certain smell. Six years later, Lee was diagnosed with Parkinson’s disease and it was then that Milne realized, after meeting other Parkinson’s disease patients, what the musky smell was.
Parkinson’s disease is a neurodegenerative disorder that results in loss of neurons that produce the neurotransmitter dopamine. The disease can lead to tremors, slow movement, and problems with walking. Currently, there is no cure for Parkinson’s, but there are treatments available to reduce symptoms.
Milne is currently working with researchers to conduct studies on the smell associated with the disease and the possibility of creating a new diagnostic test for Parkinson’s disease. The test can be considered revolutionary, as there is currently no definitive test for the disease, aside from observing patients who show symptoms.Related: 6 Diseases Caused by a Lack of Sleep