WHY DO WE FALL ILL NOTES CLASS 9TH

WHY DO WE FALL ILL

Health is considered to be the state of perfect functioning of body and mind, unhindered by diseases. Disease is the malfunctioning of the organism or a part of it due to infection, inherent weakness or environmental stress that upsets the normal physiological functioning of the organism.

Diseases are of Two Types:

·         Communicable diseases (Infectious)

·         Non-communicable diseases (Non-infectious)

Communicable Diseases

Communicable diseases are caused by the entry and development of living organisms such as virus, bacteria, protozoans, worms or fungi into the body. The organism causing the disease may be transmitted from one person to another by means of air, water, food, physical contact or insects (vectors).

The following are some of the communicable diseases. We shall now study the cause, the symptoms, prevention and control of common diseases.

Malaria

• This insect-borne disease is caused by a parasitic protozoan, plasmodium and is transmitted from person to person by the bite of an insect vector, the female anopheles mosquito.
• When a mosquito bites an infected person, the protozoa are sucked into the stomach of insect along with the blood and breed there. 
• Within ten days the young ones of the protozoan are found in the salivary glands of the mosquito. 
• The bite of this infected mosquito on a human being, will result in a small dose of the saliva along with protozoan, being injected into the person. These parasites complete their life-cycle when they enter the red blood corpuscles in man and destroy them.

Symptoms

• High fever, headache, body ache, nausea and violent shivering (rigours) are some of the symptoms of malaria. Each malarial attack lasts for 6-10 hours and consists of the cold stage (shivering), hot stage (fever) and sweating stage (temperature goes down to normal).
•  The fever is repeated on the third or fourth day. This leads to general weakness in the patient. The disease may also lead to enlargement of the liver and spleen.

Prevention

Efforts must be made to prevent mosquitoes from biting and also prevent them from breeding. Following are some such methods:

·         Use wire mesh on doors and windows to prevent entry of mosquitoes into the house

·         Use mosquito repellents to prevent mosquito bites

·         Spray kerosene on stagnant water bodies or introduce fishes that feed on mosquito larva into the water bodies, so that the larvae are killed

Example of larvae eating fishes: gamburia, minnows, trouts

·         Spray insecticides into dark corners where adult mosquitoes hide and kill them

·         Clean tanks and sumps regularly

·         Do not allow rain water to collect and stagnate in the garden

Control

Quinine which is an extract from the cinchona tree is used to manufacture chloroquinine. This is the drug for the treatment of malaria.

Influenza (flu)

This is an air borne disease caused by a virus called myxovirus influenzae.

Symptoms

Running nose, sneezing, coughing, body ache and fever are some of the symptoms of this disease.

Prevention

Avoid physical contact with patients suffering with flu.

Control

Being viral there is no known control for influenza. Fortunately it is self limiting. Relief can be given to the patient by administering a paracetemol (like crocin) but this by itself it is not a cure.

Jaundice (Hepatitis)

Jaundice is the disease that effects the liver which is caused by viral infection. The types of hepatitis are A, B, C, D, E and G.

Symptoms

Liver being a major organ connected with the digestive system, it affects digestion adversely. There is loss of appetite, eyes and skin turn yellow. Urine is dark yellow and stools are light yellow. The other symptoms are headache, temperature and pain in the joints.

Prevention

·         Use potable water that is chlorinated, boiled, filtered and ozonised

·         Prevent infection through physical contact by washing hands thoroughly after handling any article used by the patient

·         Hepatitis-B vaccine should be taken to prevent the disease

Control

·         Interferon injection may be administered by the physician to control the disease

·         Adequate rest is required for the patient to recover fast

·         Sugarcane juice, radish with jaggery are recommended

·         Fats should be avoided and protein taken within limits

Rabies (Hydrophobia)

• This is a canine disease which is transmitted to man through the bite of a mad dog (rabid) or other rabid mammals such as monkeys, cats or rabbits.
• This is a viral disease caused by a rabies virus, which is present in the saliva of the infected animal. The incubation period is 1-3 months.

Symptoms

• The patient develops severe headache, high fever, painful contractions of the throat muscles and chest. Hydrophobia (fear of water) sets in as the virus selectively attacks the brain i.e., the nervous system.
• Damage to the central nervous system causes paralysis and painful death.

Prevention

·         Wash the wound with carbolic soap, and clean water without delay soon after the bite. Apply an antiseptic and consult the doctor for anti rabies vaccine.

·         Pet dogs or cats should be immunized by getting them vaccinated with anti-rabies vaccine

·         A rabid dog can be easily identified because it will show excessive salivation and try to seek isolation after biting. To prevent further transmission of the disease the dog should be killed.

·         Rabies can be treated by Pasteur's treatment

A course of 14 vaccines are administered. Fine anti rabies vaccines are prescribed at an interval 0-3-7-14-30 days of the bite.

Control

There is no cure once the disease spreads.

AIDS

• AIDS is a disease that can prove to be fatal. The immune system of the body is affected. “Acquired Immuno Deficiency Syndrome” which is the medical expansion for AIDS was first detected in June 1981 in USA. The disease is caused by a retrovirus - HIV (human immuno deficiency virus).
•  Immune response is produced by a variety of white blood cells (WBC) called lymphocytes. The HIV attacks the lymphocytes and uses the genetic material to produce more virus particles which are released into the blood to attack more WBC. 
• This leads to destruction of the white blood corpuscles and reduces the body's defence against infections like pneumonia and also some kinds of cancer. It is a disease that is dreaded in today's world.
• HIV is transmitted when there is an exchange of body fluids from an infected person to a healthy one.
• The common modes of transmission are:

·         Sexual intercourse

·         Sharing needles to inject drugs

·         Blood transfusion

·         From HIV positive mother to unborn child

·         Razor at the hair dressing saloon

Symptoms

The interval between infection and the first appearance of symptoms is 1-10 years.

The important symptoms of AIDS are:

·         Swollen lymph nodes

·         Low blood platelet count, causing hemorrhage and fever

·         Weight loss and sweating at night

·         Severe damage to brain which may lead to loss of memory, ability to speak and think clearly

·         Due to the breakdown of the immune system the patient becomes susceptible to other infections

Prevention

The public must be educated to take the following preventive measures against AIDS.

·         A disposable or new razor should be used at the hair dresser's

·         Blood donors must be screened for HIV before they donate blood

·         Only disposable needles and syringes should be used

·         Safe sex must be practiced

Control

No effective vaccine for AIDS has been developed so far.

Tuberculosis

The bacterium that causes this disease is Mycobacterium tuberculosis which is a rod shaped bacteria spread by air, dust, sputum of infected person or even from animals. The bacterium releases a toxin called tuberculin. The disease generally affects lung tissue but may spread to any other part of the body like the brain, stomach or intestine. The disease bore a social stigma but today due to research and advancement in medicine the disease can be controlled and is no longer life threatening.

Symptoms

The first symptom observed is weight loss. The patient feels sick and weak. There is no appetite. There is low grade fever which may rise in the afternoon. Depending on the site of infection the symptoms may vary.

Lung (Pulmonary T.B.)

Here the patient has persistent cough and produces blood-stained sputum (Phlegm). There is weight loss and a feeling of weakness. Pain in the chest and breathlessness may also occur.

Lymph Gland T.B.

swelling and tenderness of lymph glands which may discharge secretions through the skin. Often the infection may be in the leg.

Prevention

·         Public awareness of health and hygiene is essential

·         BCG or Bacillus-Calmette-Guerin vaccination which contains weakened Tuberculosis bacillus is injected into the system to produce antibodies that will fight the disease

·         Cows that are milked should be immunized with tuberculin vaccine

·         Spitting in public places must be banned

Control

ATT (Anti-tubercular therapy) should be administered. Streptomycin is the drug used.

Cholera

This is a water borne disease which is transmitted by flies. The infection can occur in a global form especially during flood and other natural calamities. The bacterium that causes the disease is vibrio cholerae.

Symptoms

There is severe gastro intestinal infection which leads to vomiting, watery motions, reduced urination and dehydration. Eyes become sunken and the patient has muscle cramps.

Prevention

·         Immunization with anti cholera vaccine. The immunization lasts for 6 months

·         When the disease is rampant, boiled water cooked food and food not exposed to flies must be consumed

·         Proper sanitation and good personal hygiene in the community will prevent the spreading of the disease

·         To prevent dehydration ORS (Oral Rehydration Solution) should be administered in small drips at frequent intervals

ORS - Sodium chloride 3.5 g

Sodium bicarbonate 2.5 g

Potassium chloride 1.5 g

Glucose 20.0 g

Sucrose 40 gm

Water 1 lt.

Control

Immediate medical help is required to control the disease. Tetracycline is the drug of choice.

This is the most communicable disease in our country and effects mainly children in the age group 0-15 years. Every year 2.5 million people suffer from typhoid. Caused by bacterium salmonella typhi, it passes out through the excreta of the infected person. This is spread by houseflies or directly through contaminated food especially milk and eggs.

Symptoms

·         Headache and high temperature for three four weeks. The temperature reaches its peak in the afternoon

·         If care is not taken, relapse is common

Prevention

Proper sanitation, control of flies, anti typhoid inoculation are some of the precautions to be taken.

Control

The drug of choice is Ciproflox.

Diarrhoea

Diarrhoea manifests itself with frequent loose motions accompanied with griping abdominal pain. Bacteria such as E.coli, Shigella spp, some types of protozoa and viruses cause this disease.

Symptoms

·         Frequent loose motion and vomiting leading to dehydration

·         If neglected dehydration sets in. The patient becomes irritable, eyes look sunken, nose is pinched and the tongue and inner sides of the cheeks appear dry. There is sudden weight loss, pulse is weak accompanied with deep breathing and convulsions.

Prevention

·         Eatables should be kept covered to prevent contamination through dust and flies

·         Fruits and vegetables should be well washed with potassium permanganate, before use

·         Water should be boiled before drinking. Filtered water and mineral water are also safe

·         Proper sanitation and toilet facilities are essential

·         Proper personal hygiene, like washing hands before eating or handling food is important

·         Food that is stale or has got rancid should not be consumed

·         Public should be educated about community hygiene

Control

·         Total bed rest is advised for the patient till the illness is fully controlled

·         Frequent vomiting and loose motions can lead to dehydration. Conscious effort must be made to increase the fluid intake. ORS can be made at home using one teaspoonful of sugar and a pinch of salt dissolved in 200ml of water. ORS must be administered sip by sip at short intervals.

·         Antimicrobal drugs and anti diarrhoeal agents should be administered

·         A good home remedy is to take the pulp of boiled raw banana, turmeric, salt and lime

·         Husk of Isabgol seed (Plantago Ovata) with water or curd will give relief

Anthrax

Anthrax is a highly infectious disease caused by the bacterium Bacillus anthracis. It is a disease found commonly in domestic animals such as cows, goats and sheep, but human beings can be infected when exposed to the infected animal. The meat of the infected animal if consumed without being cooked properly can cause the disease. The spores of the bacteria are used in biological warfare.

Symptoms

Anthrax infection can occur in three forms

·         Cutaneous (skin): This type is rare but 20% of the cases result in death

·         Inhalation: Running nose followed by breathing difficulty and finally death

·         Intestinal: Nausea, loss of appetite, vomiting, pain and finally vomiting blood. This is ultimately fatal.

Prevention

Course of 4 subcutaneous infections of anthrax vaccine is adviced.

Control

If detected early it can be cured, with effective antibiotics.

Given below is a chart listing the communicable diseases we have learnt in this chapter, their symptoms, prevention and control.

Communicable Diseases

Disease	Mode of Transmission	Symptom	Prevention	Control
Malaria	Caused by protozoan plasmodium through the bite of the female anopheles mosquito	High fever, rigorous which is repeated on or 4th day	Prevent mosquitoes from biting and prevent them from breeding	A quinine derivative called chloroquinine
Influenza	Caused by virus, myxovirus influenzae which is air brone	Cough, Cold, Fever	Avoid physical contact with Influenza patients	No cure as it is viral. Crocin can give relief
Jaundice	Caused by virus. The various types are Hepatitis A, B, C, D, E and G. Spread through contaminated food and water caused by virus	Loss of appetite, yellow colouration due to excess bile pigment in the blood yellow urination fever	Hepatitis B vaccine. Use purified water. Avoid contact with infected person	Diet Control, fat free and limited amount of problem. Rest for patient. Plenty of sugarcane juice, radish, Interferon injection
Rabies	Caused by virus which is transmitted through the bite of a rabid dog	Hydrophobia, fever, headache, damage to the central nervous system, causes paralysis often fatal	1. Anti rabies vaccine to immunize house hold pets. 2. Louis Pasteur’s vaccines — a course of 14 injections at intervals of 0-3-7-14-30 days after the bite	No cure if the disease sets in
AIDS	caused by HIV (virus). Transmitted through sex, common injection needle, blood transfusion, barber’s razor	Weakness, body’s normal defence against infection breaks down	No vaccine developed so far, Practice safe sex. Avoid common razors and needles. Screen blood before transfusion	No Known cure for the disease
Tuberculosis	Caused by Mycobacterium tuberculosis spread by air, dust, spit	Lung T.B is more common. Persistent cough, blood stained mucus,breathlessness T.B can effect lymph, intense or other organs	BCC vaccine. Milch cows to be immunized against the disease. Spitting in public places to be banned	ATT (Anti Tubercular Therapy) to be administered
Cholera	Caused by bacterium vibrio cholera, transmitted by flies, is also water borne	Vomiting, watery motions, dehydration. If neglected, can be fatal	Immunization with anticholera vaccine, consume boiled water.Prevent flies from settling on food. ORS to prevent dehydration. Good sanitation and hygiene	Tetracycline to be administered under supervision of the Physician
Typhoid	Caused by bacterium Salmonella typhi, transmitted by flies or contaminated food	High temperature for 3-4 weeks with headache	Anti typhoid inoculation, good sanitation and hygiene in the community	Ciproflox to be administered under supervision of a physician
Diarrhoea	Caused by bacteria E.Coli, Shigella, some types of viruses and protozoa. Transmitted through contaminated food and water. Fly could be an agent	Frequency loose motion, vomiting dehydration	ORS to prevent dehydration, proper sanitation and hygiene. Consume hygienically prepared food and purified water	Anti dirrhoeal drugs will control the disease
Anthrax	Caused by bacterium Bacillus anthracis. Transmitted through domestic animals	Running nose, breathing difficulty and finally death	Course of 4 Anthrax vaccine injections	Can be cured if detected early. Antibodies can control the disease

NON-COMMUNICABLE DISEASES

Under this category are diseases which do not spread from an infectious person to a healthy person. These are non-infectious diseases e.g., diabetes, arthritis, heart disease and cancer. Many non-communicable diseases are caused by nutritional deficiency.

In this chapter, let us discuss the various non-communicable diseases caused by nutritional deficiency

NUTRITIONAL DISORDERS

For the healthy growth of the individual, a nourishing, well balanced diet is required. A diet has nutrients in the right proportion ensures proper growth and development of both body and mind. If the nutrients are inadequate or not in the right proportion nutritional disorders may occur.

Protein Energy Malnutrition (PEM)

Protein energy malnutrition leads to two types of diseases.

·         Marasmus

·         Kwashiorkor

Marasmus

This is due to protein deficiency and not food calories intake. In developing countries like India it is common in infants below one year of age. The causal factor may be due to early replacement of mother's milk by other foods of low protein and calorific value. This may happen if the mother has a second pregnancy when the older infant is still too young.

Symptoms

·         As the stored fats and tissue proteins are used up for the production of energy, the infant develops a shriveled look

·         Ribs become prominent and limbs become very thin as the fat layer beneath the skin disappears

·         Retarded physical and mental growth

·         Severe diarrhoea and other digestive disorders

Prevention / Control

A protein rich diet such as a combination of wheat, gram, peanut, soyabean and jaggery or a diet with animal protein like mutton, chicken and fish, will help the patient to return back to health.

Kwashiorkor

Children between 1-3 years of age must consume 1g protein/kg body weight. If they consume below this quantity they can suffer from this protein deficiency disease.

Symptoms

·         Growth is stunted, appetite is poor

·         Stomach gets distended

·         The eyes are bulging

·         The patient develops match stick legs- legs become thin, long and curved

·         Skin may become dark and start peeling off and hair may become dull and loose its lusture

Prevention / Conrol

By including food rich in protein into the diet, the disease can be cured. Wheat, gram, peanut, soyabean and jaggery are recommended.

Mineral Deficiency

Minerals are elements which are required by the body in small quantities along with food. They regulate various metabolic functions in our body.

Anaemia

Iron deficiency causes Anaemia. Iron is required by the body to form the protein haemoglobin present in the red blood cells in our body. The main function of haemoglobin is to transport oxygen from the lungs to the various parts of the body.

Symptoms

Patients suffering from anaemia become pale, lose appetite and feel exhausted.

Prevention / Control

The diet should be supplemented with liver, egg, molasses, cereal, pulses, leafy vegetables, brinjal, apple, banana, and guava which are rich in iron. The daily requirement of iron is 25mg. Care should be taken to maintain this level by including vegetables and fruit rich in iron.

Goitre

Iodine deficiency leads to this disease. Iodine is essential for the body in very small quantities for the preparation of thyroid hormone thyroxine.

Symptoms

Iodine deficiency causes abnormal enlargement of the thyroid gland which is a gland situated in the neck region. In childhood, iodine deficiency causes reduced thyroid functioning which results in retarded physical and mental growth.

Prevention / Control

The government has made it mandatory to iodise the salt consumed by the public. Besides sea food, green leafy vegetables etc are rich in iodine and if included generously in the diet will restore the normal functioning of the gland.

Intra muscular infections of iodised oil, the base being the oil from poppy seeds is also found to be effective. Sodium iodate tablets are also found to be effective.

Vitamin Deficiency

Vitamins are organic compounds which are taken along with food in small quantities. They are essential for life as they are responsible for certain metabolic activities in the body.

Vitamins are of two kinds:

·         Water Soluble

·         Fat soluble

The following are some of the diseases caused by vitamin deficiency.

Diseases caused by deficiency of fat soluble vitamins A and D.

Xerophthalmia

This disease is caused by vitamin A deficiency.

Symptoms

In a mild form this disease causes night blindness. i.e., difficulty to see in a dim light. In severe cases it may lead to permanent blindness. The symptoms are non functioning of lacrymal glands, dryness, Keratinisation of conjunctiva and cornea of the eyes.

Prevention and Control

Fish, cod liver oil, milk, butter, carrots, tomato, green leafy vegetables, papaya, guava, yellow fruits containing carotene and vegetables such as pumpkin are rich in vitamin A and if included in the diet will help prevent or control the disease.

Rickets

This disease is caused by vitamin D deficiency. Vitamin D is synthesized naturally in the presence of sunlight.

Symptoms

Deficiency of vitamin D leads to loss of Ca⁺⁺ in the urine. Due to this, no Ca⁺⁺ gets deposited in the bone. The result in deformities in the bones of the legs and ribs. This condition is called rickets and occurs in children. The patient has restricted movement of the limbs and the ribs get pigeon chested. A condition called knock knee may also occur. In adults vitamin D deficiency causeds osteomalcia. This disease occurs in people who live in conditions where there is no exposure to sunlight.

Prevention / Control

Cod liver oil, fish, milk are rich in vitamin D. If included in the diet, it prevents the disease and / or controls it.

Diseases caused by deficiency of water-soluble vitamins B₁, B₅ and C.

Beri - Beri

Vitamin B₁ deficiency causes this disease. This water soluble vitamin is also called Thiamine or anti beri beri or antineuritic factor. Beri beri is common in areas where polished rice (dehusked rice) is the major food item.

Symptoms

Partial paralysis of the skeletal muscles, muscular dystrophy, enlargement of the heart, digestive disturbances, nervous disorder and polyneurites are some of the symptoms of Beri Beri.

Prevention / Control

Cereals, pulses, nuts, green leafy vegetables all contain high amounts of vitamin B₁. Liver, kidney, milk, and egg yolk also contain vitamin B₁. If included in the diet, it prevents the disease and / or controls it.

Pellagra

This disease is caused by the deficiency of vitamin B_5. The vitamin is also refered to as Niacin or Nicotinic acid or Pellagra preventing factor. Pellagra is prevalent in areas where maize is the staple food. Maize inhibits the absorption of vitamin B₅ into the system and thus, this deficiency leads on to Beri Beri.

Symptoms

This disease is characterised by dermatitis (skin inflammation), diarrhoea and dementia (loss of memory). The disease is often fatal.

Prevention / Control

Cereal husk, peas, beans, lean meat, liver, milk, eggs, nuts and fish all contain vitamin B₅. Including these into the diet will prevent and/or control the disease.

Scurvy

Vitamin C (ascorbic acid) deficiency causes Scurvy.

Symptoms

This disease is characterised by bleeding gums, loosening of teeth, muscular and joint pain, along with general weakness, fatigue, loss of weight and poor healing power.

Prevention / Control

Citrus fruits like lemon and orange, tomatoes, cabbage and leafy vegetables contain vitamin C and should be included in the diet. Vitamin C tablets are also available to supplement the body's requirement.