09 Sep

Diseases – 2

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Content

• Neglected Tropical Diseases (NTDs)
• Non-Communicable Diseases
• Rare Genetic Diseases

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1) NEGLECTED TROPICAL DISEASES (NTDS)

• WHO Definition:
  • NTDs are a diverse group of 20 conditions that are mainly prevalent in tropical areas, where they mostly affect impoverished communities and disproportionately affect women and Children.
    • The epidemiology of NTDs is complex and often related to environmental conditions.
    • They are caused by variety of pathogens – viruses, bacteria, protozoa, and parasitic worms (helminths).
• Which are the diseases included in NTDs:
  • Buruli Ulcer, Chagas Disease, Dengue & Chikungunya, dracunculiasis (Guinea-worm disease), echinococcosis, foodborne trematodiases, human African trypanosomiasis (sleeping sickness), leishmaniasis, leprosy (Hansen’s disease), lymphatic filariasis, mycetoma, chromoblastomycosis and other deep mycoses, onchocerciasis (river blindness), podoconiosis, rabies, scabies, and other ectoparasitoses, schistosomiasis, soil-transmitted helminthiases, snakebite envenoming, taeniasis/cysticercosis, trachoma, and yaws and other endemic treponematoses.
• Note:
  • ‘Noma‘ is the latest addition to WHO’s list of neglected tropical diseases (Dec 2023)
• These diseases are contrasted with the “big three” infectious diseases (HIV/AIDS, tuberculosis, and malaria), which generally receive greater treatment and research funding.
• Jan 30: World NTD Day

• • In May 2021, the delegates at the 74th World Health Assembly unanimously adopteda proposal to declared Jan 30 as ‘World NTD Day.
• WHO’s new roadmap for 2021-2030 calls for three strategic shifts to end NTDs:
  • From measuring process to measuring impact.
  • From disease-specific planning and programming to collaborative work across sectors.
  • From externally driven agendas reliant to programmes that are country-owned and country-financed

 

INCLUSION OF NOMA ON THE WHO’S LIST OF NTD

It is a severe gangrenous disease of the mouth and face. It primarily affects young children (between the ages of 2 years to 6 years) in regions of extreme poverty. It starts as an inflammation of gums, which, if not treated early, spreads quickly to destroy facial tissues and bones. Cause: Evidence indicate that NOMA is caused by bacteria found in the mouth. There are multiple risk factors associated with the disease. It includes malnutrition, weakened immune system, infections, and extreme poverty. If the child is malnourished and has recently been sick with an infectious disease, such as measles or chickenpox, they are at more risk for developing noma. It is not contagious but tends to strike when the body's immune system is weak. Impact: It can be fatal and may also cause severe disfigurement for survivors. Treatment: It involves antibiotics, advice and support on practices to improve oral hygiene with disinfectant mouth wash and nutritional supplements. In case of early diagnosis, proper wound healing without long-term consequences may take place. In severe cases, surgery may be necessary. Cases are mostly found in sub-Saharan Africa. Some cases are also reported from Americas and Asia. Accurate estimation of the number of noma cases is challenging due to rapid progression of the disease and the associated stigma.

NOMA is sometimes called the 'Face of Poverty' as it is a social marker of extreme poverty and malnutrition. Significance of Including NOMA in the NTD's list: ▫ Amplify global awareness. ▫ Catalyze research, stimulate funding and boost efforts to control the disease through multisectoral and multi-pronged approaches.

2) NON-COMMUNICABLE DISEASES

1) HYPERTENSION (HIGH BLOOD PRESSURE)

• Why in news?
  • Who releases its first-ever report on global impact of high BP, states approximately four in every five not treated adequately (Sep 2023)
• What is Blood Pressure?
  • Blood pressure is a measure of how much the blood moving through your arteries pushes against the vessel walls. According to medical standards, the reading on a doctor’s BP monitor going above 140/90 accounts for hypertension. High Blood Pressure (Hypertension) is a serious medical condition that significantly increase the risks of heart, brain, kidney and other diseases.
  • A large number of people who suffer from hypertension are unaware of this, therefore it is also sometimes referred as a silent killer.
  • It is a condition that knows no boundaries affecting people of every age and different socio-economic conditions. It can’t be cured but can be managed through lifestyle changes, medication, and regular monitoring.
• WHO Report on Global Impact of High BP (Sep 2023)
  • Hypertension affects 1 in 3 adults worldwide and around 1/3rd of the adults with hypertension are unaware of their conditions. Nearly 4/5 people with hypertension are inadequately treated. Scaling up coverage can avert 76 million deaths between 2023-2050.
• The number of people living with hypertension (blood pressure of 140/90 mmHg or higher or taking medication for hypertension) doubled between 1990 and 2019, from 650 million to 1.3 billion.
• Hypertension Situation in India:
  • As per a paper published in The Lancet:
    • Hyper Tension is the most important risk factor for death and disability in India.
      • Less than 1/4th of hypertensive patients in India had their blood pressure under control during 2016-2020.
    • There is a growing prevalence of hypertension amongst younger adults and those from lower socioeconomic backgrounds.
  • NFHS-5 reported a hypertension prevalence of 24% in men and 21% among women, an increase from 19% and 17% respectively from the previous round (NFHS-4)
• Key Issues with Hypertension situation in India:
  • Lack of Awareness: As per WHO, 1/3rd of the hypertension patients don’t even know that they are suffering from hypertension.
  • Limited Access to healthcare services
  • Inadequate adherence to medication and lifestyle modifications

 

A) BENEFITS OF REDUCING SALT INTAKE (DEC 2022)

• Details of the study:
  • This was a large study where over 1.76 lakh participants from the UK Biobank were followed up for an average of 11.8 years. Nearly 7,000 attacks and over 2,000 strokes were documented during the period.
• Key Highlights:
  • Adding less salt to food -> Fewer heart attacks and strokes.
    • This was found to be true even in participants who were following DASH diet (Dietary Approaches to Stop Hypertension).
    • DASH is the best recommended diet to prevent cardiovascular events. It involves eating fruits, vegetables, lean meat, poultry, nuts, whole grains, and reducing intake of saturated fats, cholesterol, and sugar.
    • WHO recommends only 5 gm of salt per day.
• Other key things to know:
  • Sodium intake from processed and restaurant food contributes to high rates of high blood pressure, heart attack, and stroke. Reducing sodium intake could prevent thousands of deaths annually.

2) DIABETES AND INSULIN

 

A) WHAT IS DIABETES?

• A medical condition when person’s blood sugar level is too high.
• It is classified in two types:
  1. Type 1 diabetes: This type of diabetes appears in childhood where body can’t make insulin or make insufficient Insulin, a hormone that regulates blood sugar level. It helps glucose get into cell. This condition occurs because body’s immune system attacks the cells in the pancreas that make insulin.
  2. Type 2 diabetes: The body doesn’t make enough insulin or when cells are not responding to insulin. This type of diabetes is associated with obesity and can lead to blindness, strokes, heart disease and even death.

 

TYPE 1 DIABETES LEADING CAUSE OF DIABETES DEATHS IN THOSE BELOW 25, EASILY PREVENTABLE: STUDY PUBLISHED IN LANCET

• Type 1 diabetes in those below 25 years accounted for at least 73.7% of the overall 16,300 diabetes deaths in this age group in 2019. This is despite fatalities from this condition being largely curable.
• The death rate varied based on the Socio-demographic index (SDI) of a country.
  • Countries on the higher end of the SDI spectrum recorded 0.13 deaths per 100,000 people.
  • Countries on the low middle SDI spectrum recorded 0.6 deaths per 100,000 people.
  • Countries on low SDI spectrum recorded a 0.71 per 100,000 population death rate.
    • Myanmar (1.93/1,00,000 population), Papua New Guinea (1.78 per 100,000 population) and Haiti (1.57 per 100,000 population) had the highest age-standardized death rates for diabetes.

INSULIN

• Details
  • Insulin is a peptide hormone produced by pancreas. Inside the pancreas, the hormone insulin is made in the beta cells, which are part of islets of Langerhans. With each meal, beta cells release insulin to help the body use or store the blood sugar it gets from the food.
  • In the beta cells, insulin is first created as a big molecule called “proinsulin“. Proinsulin is broken into two pieces: Insulin and C-Peptides.
  • Note: Insulin cannot be taken as pill as it would be broken down during digestion just like the protein in food. It must be injected into the fat under your skin for it to get into your blood.
• Discovery of Insulin:
  • Insulin was discovered in 1921 by Sir Frederick G Banting, Charles H Best, and JJR Macleod at the University of Toronto in 1921 – after which it was purified by James B Collip for safer testing on humans. It was the greatest medical breakthrough of the 20th century and remains the go-to treatment for type-1 diabetes globally today.
    • Note: Back in the 19th century, those suffering from type-1 diabetes were rarely expected to live longer than a year or two after detection. This happens because type-1 diabetes is an autoimmune disease where the body destroys the cluster of cells in the pancreas
  • In Jan 1922, Leonard Thompson was administered first dose. Banting and Macleod went on to win the Nobel prize in Physiology or Medicine on Oct 25, 1923.
  • Important Video: 100 years of insulin use: How it was discovered and where we stand today
• Situation today:
  • Globally, 15/1 lakh people suffer from type-1 diabetes. The international diabetes federation have estimated that 451 million adult suffered from diabetes worldwide in 2017. This would increase to 693 million by 2026 if not effective prevention methods are adopted.

 

NON SUGAR SWEETNERS

• What are non-Sugar Sweeteners?
  • Non-Sugar Sweeteners (NSS) or Non-Nutritive Sweeteners (NNS) are substances used in place of sweeteners that have sugar (sucrose) or sugar alcohols. They have negligible or zero calories because, unlike sugar, they don’t get broken down by the body into products that provide energy or calories.
  • They are used as tabletop sweeteners as well as in food items marked as ‘Sugar Free’, ‘Diet’ etc.
  • They are of primary two types – i) Artificial, ii) Natural
    • Artificial: These NSS are prepared in laboratories. Examples include Aspartame, Saccharine, Acesulfame-potassium, Sucralose, Neotame (derived from aspartame), Advantame (derived from aspartame) etc.
    • Natural: These are extracted from plants (e.g. Stavia, Thaumatin, Monk Fruit etc.)
  • All the six artificial NSS and 3 natural NSS are approved by the US Food and Drug Administration. India’s FSSAI has also approved all of them (except Advantame, and Monk Fruit).
• Why are they used?
  • TO reduce consumption of sugar (which has led to global rise in diabetes and obesity).
• Market:
  • As per a report by global market consultancy The Business Research Company the market for these NSS was worth $20 billion in 2022 and it is expected to reach about $30 billion by 2027.
• Criticisms:
  • Little Evidence to substantiate the benefits of NSS in controlling diabetes and obesity.
  • Growing body of research says that these NSS may lead to cardiovascular diseases, cancers, and type-2 diabetes.
    • For e.g. WHO in its July 2023 guidelines have classified Aspartame as “possibly carcinogenic o humans”.

 

PRELIMS FACTS: ASPARTAME:

Aspartame is an artificial sweetener which was invented in 1965 and has been in use in USA since early 1980s.

It is a compound of carbon, hydrogen, nitrogen, and oxygen with chemical formula C14H18N2O5.

It is among the most popular sugar substitute used in the world. Several Studies have highlighted problems associated with Aspartame:

• TheWHO analyzedsome1,300studies,andcitedthefollowing three, to declare aspartame “possibly carcinogenic to humans) -> European Journal of Nutrition, 2016; Cancer Epidemiology, 2022; Cancer Epidemiology, Biomarkers & Prevention, 2022;

• WHO has placed aspartame in Group 2B. This group consist of those substances which are possibly carcinogenic.
• Details about various Groups:
  • Group-1: Carcinogenic: These substances have shown sufficient evidence in humans and animals to be treated as carcinogenic. It includes tobacco smoking, alcohol consumption, Solar Radiation, ionizing radiation.
  • Group-2A: Probably Carcinogenic: Limited evidence in humans but sufficient evidence in animals. It includes insecticide DDT, Red Meat, Night Shift Work, Emission from high temperature frying etc.
  • Group-2B: Possibly Carcinogenic: Limited evidence in humans or sufficient evidence in animals. It includes aspartame, gasoline engine exhaust, heavy metal lead;
  • Group-3: Not classified as carcinogen: Inadequate evidence in humans an in animals. It include coffee, Mercury, Paracetamol, crude oil etc.

3) RARE GENETIC DISEASES

• Introduction
  • A rare disease is a health condition of low prevalence that affects a small number of people compared with other prevalent diseases in general population.
    • They generally include genetic diseases, rare cancers, infectious tropical diseases, degenerative diseases etc.
  • The most common rare diseases recorded in India are Haemophilia, Thalassemia, sickle cell anaemia, primary immuno-deficiency in children, auto-immune diseases, Lysosomal storage disorders such as Pompe disease, Hirschsprung disease, Gacher’s disease, Cystic fibrosis etc. These diseases may be impacting around 70 million people from India, 50% of which are children.
• Why special focus is needed for rare diseases / Need of a separate policy on Rare Diseases
  • High cost of treatment or no treatment -> not affordable for most of the citizens -> health insurance generally excludes rare diseases.
    • Available are primarily expensive because pharma companies are not interested in R&D as the number of patients for each disease is very less (Orphan Drugs)
    • As per WHO, only 5% of the identified rare diseases have treatment.
    • Difficult to diagnose.
    • Early screening generally doesn’t happen because of lack of awareness among primary care physicians, lack of adequate screening and diagnostic facilities etc. There are very few medical professionals who can deal with these diseases
    • Currently there is inadequate insurance cover and treating practitioners are lacking management practices.

1) NATIONAL POLICY FOR RARE DISEASES, 2021

• MoH&FW came up with the policy in March 2021.
• It aims to lower the high cost of treatment for rare diseases with increased focus on indigenous research with the help of a National Consortium to be set up by Department of Health Research, MoH&FW as convenor.
• It envisages creation of a national hospital based registry of rare diseases so that adequate data is available for definition of rare diseases and for R&D.
• It focuses on early screening and prevention through primary and secondary healthcare infrastructure such as H&W Centres and District Early Intervention Centres (DEICs) and through counselling of high risk parents.
  • Screening will also be supported by NIDAN Kendras set up by the DBT.
• The policy aims to strengthen tertiary health care facilities for prevention and treatment of rare diseases through designating 8 health facilities as Centre of Excellence and these CoEs will also be provided one-time financial support of upto Rs 5 crores for upgradation of diagnostic facilities.
• Provision for financial support: The policy was amended in May 2022. It now provides a financial assistance of upto Rs 50 lakh for treatment of rare diseases of all categories.
• The policy also envisages a crowd funding mechanism in which corporates and individuals will be encouraged to extend financial support through a robust IT platform for treatment of rare diseases.
  • Funds so collected will be utilized by CoEs for treatment of all three categories of rare diseases as first charge and then the balance financial research could also be used for research.
• Performance of the policy (Critical Analysis) (Jan 2023)
  • LS MP Varun Gandhi have written to Union Health Minister and have said that more than 4,00 identified patients of rare diseases – mostly children – are yet to receive the Rs 50 lakh financial assistance for treatment guaranteed by the Union Government under the National Policy for Rare diseases, 2021.
    • More than 10 children who were awaiting treatment have already lost their lives.
  • The 10 CoEs constituted under the policy are yet to seek financial assistance (crowdfunding) for patients with rare diseases.

1) SOME RARE GENETIC DISEASES IN MORE DETAILS

 

A) SICKLE CELL ANAEMIA

• Why in news?
  • The first therapy based on gene editing technology Crispr-Cas9 for Sickle cell disease and thalassemia has been approved in UK (Nov 2023)

About Sickle Cell Anaemia: It is one of a group of inherited disorders known as Sickle Cell Diseases. It affects shape of the red blood cells which carry oxygen to all parts of the body. RBCs are usually round and flexible so that they move easily through the blood vessels. But, in sickle cell Anaemia, some of the RBCs are shaped like sickle and also become rigid and sticky. This slows or blocks blood flow. Note: Both Sickle Cell Anaemia and thalassemia are caused by errors in the gene for haemoglobin, a protein in the red blood cells that carry oxygen to organs and tissues. Symptoms: Anaemia -> fatigue; Episodes of extreme pain called pain crises; Swelling of hands and feet; delayed growth and puberty; Vision problems etc.

 

THE UK DRUG REGULATOR, IN A LANDMARK BREAKTHROUGH, IN NOV 2023 APPROVED A GENE THERAPY FOR THE CURE OF SICKLE CELL DISEASE AND THALASSEMIA.

• This therapy is called Casgevy. It is the first licensed therapy in the world based on gene editing technology CRISPR-CAS9. This therapy edits the faulty gene that leads to these blood disorder, potentially curing person for life.
• How does the therapy work?
  • The therapy uses the patient’s own blood stem cells, which are precisely edited using Crispr-Cas9. A gene called BCL11A, which is crucial for switching from foetal to adult is targeted in the therapy.
  • Foetal haemoglobin, which is naturally present in everyone at birth, doesn’t carry the same abnormalities as adult haemoglobin. The therapy uses the body’s own mechanisms to start producing more of this foetal haemoglobin, alleviating the symptoms of the two conditions.
• How is the therapy prepared and given:
  • Casgevy is one time treatment for which the doctor has to first collect blood stem cells from the bone marrow using a process called apheresis – used to filter out the blood for different components. The cells are then sent to the manufacturing site where it takes about six months for them to be edited and tested.
  • Then the edited cells are then transplanted. Before this doctor gives a conditioning medicine for a few days to clear the bone marrow of other cells that will be replaced by modified cells.
  • The patient has to stay in hospital for at least one month so that the edited cells take up the residence in bone marrow and start making RBCs with normal haemoglobin.
• Side effects from the treatment are similar to those associated with autologous stem cell transplants, including nausea, fatigue, fever and increased risk of infection.
• Key challenges of the treatment:
  • Very Costly: it is estimated that the therapy will cause around $2 million per patient, which is in line with other gene therapies.
  • Absence of local manufacturing technology: This means that the harvested blood stem cells have to be sent across countries.
  • Preventing the misuse of CRISPR-CAS9:
• Situation in India:
  • An estimated 30,000 – 40,000 children in India are born with this disorder every year. Thus, India has one of the highest burdens of sickle cell anaemia in the world.

Steps taken by India:

• In Budget 2023-24, a Mission to Eliminate Sickle Cell Anaemia by 2047 was announced. It entails awareness creation, universal screening of 7 crore people in the age group of 0-40 years in affected tribal areas, and counselling through collaborative efforts.

 

B) THALASSEMIA:

• Thalassemia is an inherited blood disorder in which the body makes an abnormal form of hemoglobin.
  • If both of your parents are carriers of thalassemia, you have a greater chance of inheriting a more serious form of disease.
• The disorder results in excessive destruction of RBCs, which leads to anemia.
• Treatment Option
  • Blood Transfusion
  • Bone Marrow transplantation
  • Medication and supplements
  • Possible surgery to remove spleen or gallbladder.
• Situation in India
  • India is the thalassemia capital of the world with 40 million carriers (highest in the world) and over 1,00,000 patients (Majors) under blood transfusion every month. It is the most common genetic blood disorder that is prevalent in India.
  • People suffering from the disease are unknowingly transferring on this genetic disorder to their children.
• Around 10,000 births of Thalassemia major are taking place every year.
  • Most of the thalassemia treatment takes place in private sector with out-of-pocket expenses.
  • The 2021 policy and associated benefits haven’t been operationalized yet.
• World Thalassemia Day
  • It is observed on May 8 every year to commemorate Thalassemia victims and to encourage those who struggle to live with the disease.
  • The day was created by Thalassemia International Federation (TIF) in 1994.
  • Theme for 2023: “Strengthening Education to Bridge the Thalassemia Care gap”

 

C) HUNTER SYNDROME OR MPS-II

• It is a very rare inherited, genetic disorder caused by a missing or malfunctioning enzyme iduronate 2-sulfatase. This enzyme’s job is to break down certain molecules (large sugar molecules called glycosaminoglycans), and without enough of this enzyme, the molecule build up in harmful amounts.
• The buildup of massive amounts of these harmful substances eventually causes permanent, progressive damage affecting appearance, mental development, organ function and physical disabilities.
• The condition is one type of a group of inherited metabolic disorders called mucopolysaccharidoses (MPSs). Hunter syndrome is also known as MPS II.
• Cure: There is no cure for hunter syndrome. Treatment involves managing symptoms and complications.
• It mainly affects males.
  • It is caused by a defective X chromosome. For females, even if one X chromosome is defective, the other may provide the correct gene. But males have only one X chromosome and hence the defective X chromosome would lead to Hunter Syndrome.

 

D) HAEMOPHILIA A AND HAEMOPHILIA B (ALREADY DISCUSSED WITH BIOTECHNOLOGY)