I remember attending a Monday morning medicine meeting in Sion Hospital, as a 3rd year medical student in the mid-80s, where a medicine lecturer presented a patient with neurological symptoms and signs that were typical of multiple sclerosis (MS). As soon as he finished, all hell broke loose and every senior physician (except his own boss who had asked him to present the case) castigated him, saying “multiple sclerosis does not occur in India and definitely not in the low income patient population that frequents Sion Hospital”. Funnily, the Multiple Sclerosis Society of India (MSSI) had just been founded, in 1985.
Multiple sclerosis (MS) is an inflammatory condition of unknown origin that affects the brain and spinal cord  and can be both acute and chronic. Prior to 1987, MS was considered extremely rare and was said to occur mainly in Parsis  or people of high socio-economic status with a prevalence of between 0.17 to 1.33 per 100,000 in the 1970s, which would mean there were about 6231 patients in 1975 given a prevalence of 1%. This is obviously rare and hence it was truly believed that Indians are “different” (just the way we believe Covid-19 affects us differently, a “meme” that even Siddhartha Mukherjee of “The Emperor of All Maladies” fame bought into recently with his article in The New Yorker) and that MS is a disease of the affluent West, which is why it was likely considered commoner in Parsis.
There were also very few neurologists at the time and no other tests to help make the diagnosis.
Then the first MRI scanner in Mumbai and the second in the country was installed in Breach Candy Hospital by Dr. Viral Shah. Suddenly in the next 6 months, there was an “epidemic” of MS. Many patients who otherwise would never have been diagnosed to have MS clinically, turned out to have classic MRI pictures of MS. Virtually overnight, the physicians and neurologists changed their thinking and accepted that MS occurs equally commonly in India as in other parts of the world.
In 2013, the Multiple Sclerosis International Federation (MSIF) estimated a prevalence of MS of around 5%  in India and by 2020, the prevalence had jumped to 11%. 145,000 people are now estimated to be living with MS in India . It is not as if the disease has become more common. Most physicians in India blindly accepted the existing dogma that MS was very rare and pretty much didn’t exist in India and only when MRI scans provided irrefutable proof, did we change our thinking. And now with more neurologists, more MRI scanners and better awareness, we are picking up MS more and more in all sections of society.
But, imagine if you were a patient in 1970 with classic signs and symptoms of MS. The chance that the diagnosis would be made correctly unless you were of Parsi origin, was slim and even if a physician thought of MS, they would not really have had the guts to make the diagnosis and go against the prevailing thinking that “MS doesn’t really exist in India, except in Parsis and in the rarest of rare situations”… unless you had the fortunate “matka” of landing up with a neurologist who had the confidence and knowledge to make that diagnosis…and there just weren’t enough of them at the time.
“The eye cannot see what the mind does not know” is so apt. DH Lawrence’s twist “what the eye doesn’t see and the mind doesn’t know, doesn’t exist”, makes even more sense in this context.
Here is another example.
As a medical resident, I remember a surgical unit head and his senior registrar coming down to the radiology department in Sion Hospital in 1990. We were discussing varicose veins and thrombosis (clotting) of the leg veins and the unit head made a statement I have never forgotten. “Pulmonary thromboembolism (clots in the arteries of the lungs) doesn’t occur in India, unless the patient is Parsi or has fair skin and blue eyes”. While pulmonary thromboembolism (PTE) was and is a common cause of death in the postoperative period in the Western world, almost every patient who died of a sudden post-operative complication in the ICU prior to 1995 in India was assumed to have had a “heart attack” or some other cause of death  . The advent of spiral CT scans around the late 90s allowed us to make a diagnosis of PTE very easily and just like with MS, there was suddenly an “epidemic” of patients with PTE. And it is now an accepted fact that PTE is equally common in India as in other parts of the world .
But, imagine if you were a patient in 1980 with acute chest pain 6 days after a surgery for a hip fracture. No one would have considered the diagnosis of PTE, unless you were of Parsi ethnicity and you would have likely died because of inappropriate diagnosis and treatment.
It is amazing how these “memes” like the “CT scan of the chest for Covid-19” meme that has gone “viral”, with no evidence or rationale at all, exist countrywide…something that I spoke and wrote about last week.
Similarly “sarcoidosis does not occur in India except in Kolkata Marwaris” was a common refrain before 1991, until the advent of high-resolution CT scans, which showed typical features of sarcoidosis in the lungs (it can be mistaken for tuberculosis easily), which upended that theory as well. The same was true of Crohn’s disease, which also can be mistaken for tuberculosis and even breast cancer, but more about that another time.
It is not easy for doctors or for the healthcare system in India. Our quadruple health whammy of being a poor country with a high incidence and prevalence of both communicable and non-communicable diseases with a significant dearth of doctors and health-care workers makes it easy for memes such as these to propagate throughout the country…until there is incontrovertible proof that these theories are wrong.
What is your matka here? If you happen to have a disease that is believed to “not exist”…you are in trouble. Ironically, I can’t even think of such a disease, because…“what the eye doesn’t see and the mind doesn’t know, doesn’t exist”. Get it?
2. Singhal BS. Ann Indian Acad Neurol 2015;18 (Suppl 1):S2
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