DISEASES

Important points to remember :

1. There are microorganisms around us. Some of these produce

diseases and cause harm to us. They enter our body through

food, water or air. Those who have weak resistance power get the

disease and develop the symptoms of the disease.

2. When a person gets a disease, his physical and mental condition

and overall health are affected.

3. Types of diseases : On the basis of their mode of spreading,

diseases are classified into : (1) epidemic diseases

(2) communicable diseases and (3) contagious diseases. Microorganisms

like bacteria and viruses cause diseases.

(1) Epidemic diseases : Changes in the weather or

contamination of water can cause infection of disease to

many people to get the same disease at the same time. Such

diseases are called epidemic diseases. Cholera, typhoid,

influenza (flu), diarrhoea, conjunctivitis are epidemic

diseases.

(2) Communicable diseases : Diseases which are spread

through air by germs in the vicinity are called

communicable diseases. e.g. tuberculosis and influenza.

(3) Contagious diseases : Diseases spreading through direct

and close contact with the diseased person are contagious

diseases. e.g. scabies, eczema, etc.

Incubation Period : Incubation period is the period between

the entry of a virus or a bacterium and the appearance of

symptoms of disease. Each disease has a specific incubation

period.

The Pulse Polio Campaign : In India, every child under the age

of five years is given two doses of polio vaccine on two fixed days.

This campaign is administered by National Department of

Health for total eradication of polio. This vaccination helps to

strengthen the resistance of the children under the age of five

years. These doses are called booster doses and are given with

an interval of six weeks between them.

Tuberculosis Eradication Campaign : Tuberculosis is the

most easily communicable disease. Therefore, WHO (World

Health Organization) runs a tuberculosis eradication

campaign. Direct Observation Treatment (DOT) centres which

provide excellent medicines to the patients are set up for this

purpose. The treatment is given free of cost at these centres.

7. Cholera vaccine : Vibrio cholerae is the bacterium which

spreads cholera. Human beings are the only carrier of this

bacterium. To prevent the spread of epidemic of cholera,

the Health Department gives vaccines to people going on

pilgrimage or travelling abroad.

 Dehydration : Dehydration is the condition when the body

cells become dry due to loss of water. Oral Rehydration Solution

(ORS) is to be given to the patient in case of such dehydration.

Sugar, salt and water in ORS are absorbed in the body and give

temporary relief.

  General Measures for prevention of diseases :

(1) Drinking boiled and filtered water.

(2) Taking a balanced diet.

(3) Following healthy habits.

(4) Maintaining personal hygiene and keeping the

surroundings clean.

(5) Timely and proper medical treatment.

 Vaccination programmes against following diseases are

undertaken by the Government for protecting children :

(1) BCG (Anti tuberculosis) (2) Triple vaccine (DPT)

(Against diphtheria, whooping cough and tetanus) (3) Polio

(4) Measles (5) Double vaccine (diphtheria and tetanus) and

(6) Hepatitis B.

 AIDS– Acquired Immuno Deficiency Syndrome :

(1) In 1986, Dr. Monteniere and Dr. Gallo discovered HIV

(Human Immuno-deficiency Virus).

(2) AIDS is caused by HIV (Human Immuno-deficiency Virus).

(3) AIDS patient loses the ability to fight against any diseases

and thus contracts various infections.

(4) In 1986, WHO started worldwide AIDS Control Programme.

While in India, National AIDS Control Programme was

started in 1987.

  Chickenpox :

Modes of infection : (1) Virus enters through air that is

breathed in. (2) Contact with infected person. (3) Using

infected person’s clothes, utensils, etc.

Main Symptoms : (1) High fever (2) Headache (3) Small

blisters or boils on the skin (4) Scabs formed on blisters

within a few days.

Preventive measures and treatment : Vaccination,

Proper sanitation and medical treatment.

 Polio :

Modes of infection : (1) Contaminated food (2) Contaminated

water (3) Minute particles in the air.

Main symptoms : (1) Fever (2) Reddening of throat

(3) Muscles of back and legs are strained (4) Weakness of

the muscles of arms and legs (5) Arrested growth of

muscles (6) Disability caused due to flaccid muscles.

Preventive measures and treatment : (1) Vaccination

(2) Proper Medical treatment.

Rabies :

Mode of infection :

Bite of an affected dog, monkey, cat or rabbit.

Main symptoms : (1) Fever (2) Severe headache

(3) Rigid, painful and contracted throat muscles

(4) Inability to swallow any liquid (5) Hydrophobia (Fear

of water) (6) Delirious condition (7) Flaccid limbs and

spasms.

Preventive measures and treatment : (1) Cleaning the

site of bite. Flushing the wound with soap and water

(2) Immediate medical treatment and anti-rabies

vaccination (3) Giving pets the vaccination against rabies.

Tuberculosis :

Modes of infection : (1) Germs enter the air through a

patient’s spittle (2) The disease spreads through the air.

Main symptoms : (1) Low grade fever (2) Constant cough

(3) Blood in spittle (4) Loss of body weight (5) Chest pain

(6) Difficulty in breathing.

Preventive measures and treatment : (1) BCG vaccination

(2) Isolation of the patient (3) Proper medical treatment.

Typhoid :

Modes of infection : (1) Contaminated food (2) Contaminated

water (3) Houseflies spreading the disease.

Main symptoms : (1) Fever lasting for a definite period

(2) Rose-coloured rashes on the chest (3) Diarrhoea

(4) Headache.

Preventive measures and treatment : (1) Preventive

vaccination (2) Drinking boiled water (3) Avoiding

uncovered outside food (4) Eating clean, hygienic and

home-cooked food (5) Following public hygiene (6) Taking

chlromycetin antibiotic.

  Cholera :

Mode of infection : Food or water contaminated by

houseflies.

Main symptoms : (1) Severe diarrhoea (2) Vomiting

(3) Dehydration resulting into dry skin (4) Sunken eyes

(5) Pain in the stomach (6) Muscular cramps in legs.

Preventive measures and treatment : (1) Maintaining

public hygiene (2) Controlling houseflies (3) Uncovered

food should not be consumed (4) Drinking clean and boiled

water (5) Preventive vaccination against cholera.

Enteritis :

Mode of infection : Contaminated water and food.

Main symptoms : (1) Inflammation of the inner lining of

the intestine (2) Stomachache (3) Fever (4) Vomiting

(5) Loss of appetite (6) Diarrhoea or constipation (7) Loss

in body weight.

Preventive measures and treatment : (1) Using safe and

clean food and water (2) Personal hygiene and cleanliness

(3) Keeping the food covered (4) Proper medication.

 Diarrhoea :

Modes of infection : (1) Contaminated water and milk

(2) Spread through food by houseflies.

Main symptoms : (1) Loose motions (2) Dehydration due

to loss of water from the body (3) Sunken eyes (4) Dry

mouth and lips (5) Hands and feet become cold (6) Reduced

proportion of urine (7) Slow pulse rate.

Preventive measures and treatment : (1) Giving Oral

Rehydration Therapy (ORT) (2) Drinking boiled and cooled

water (3) Keeping personal cleanliness and hygiene

(4) Preventing dust, flies, etc. from settling on the food

(5) Keeping kitchen area clean (6) Washing fruits and

vegetables clean before consumption (7) Proper medication.

Answer the following questions :

* What is meant by epidemic diseases ?

Ans. (1) When there are certain changes in the weather or

sudden contamination of water, many people catch infection at the

same time. (2) When many people fall sick simultaneously due to

certain disease, it is known as an epidemic. (3) Disease causing an

epidemic are known as epidemic diseases. (4) Cholera, typhoid,

influenza, diarrhoea, conjunctivitis, etc. are epidemic diseases.

*  What is meant by communicable diseases ?

Ans. (1) Communicable diseases are the diseases caused due

to constant sharing of space with diseased persons. (2) The germs of

such diseases enter a healthy person’s body through the air.

(3) Tuberculosis, influenza, cough, cold, etc., are communicable

diseases.

* Why should a person suffering from tuberculosis avoid

going to public places ?

Ans. (1) Tuberculosis is the most easily communicable

disease. (2) It is estimated that in India, one T.B. Patient dies every

two minutes. (3) The bacteria from the spittle of a patient enters

into the air. (4) These bacteria may infect other healthy persons.

Therefore, a person suffering from tuberculosis should avoid going

to public places.

What is meant by a contagious disease ?

Ans. (1) The disease which is transmitted through direct or

close contact with a patient is known as a contagious disease.

(2) The germs of the disease enter into the healthy person’s body

through close contact. (3) Skin diseases such as eczema and scabies

are contagious diseases.

(5) What is incubation period ?

Ans. (1) The symptoms of any disease does not appear

immediately after the germs enter the body. (2) The germs such as

viruses or bacteria take some time to grow in the body and then

show the symptoms. (3) The period between the entry of disease

causing germs in the body and appearance of the symptoms is called

the incubation period. Each disease has a specific incubation period.

What is the mode of infection of chickenpox? What are

its symptoms?

Ans. 1. Mode of infection : (1) Chicken pox is the disease

caused by virus. (2) The virus enters the body through the air that

is breathed in. (3) Contact with an infected person also spreads the

infection of chickenpox. (4) Using infected person’s clothes and

utensils can also pass the infection.

Symptoms of chicken pox : (1) After the viral infection,

person gets high fever. (2) There is severe headache. (3) Small boils

develop on the skin. These boils appear like blisters. (4) Scabs

develop on these blisters which fall off within a few days.

How is rabies caused ? What are the symptoms of

rabies ?

Ans. (1) Rabies is a disease caused by virus. (2) The virus of

rabies is transmitted to human beings by bite of an affected dog.

(3) Other animals like monkey, cat or rabbit can also be affected by

rabies and their bite can cause rabies to human beings.

Symptoms of rabies : (1) There is severe headache and fever.

(2) Due to rabies, the throat muscles become rigid and contracted

causing severe pain in the throat. (3) Patient is unable to swallow

any liquid and even water. (4) Hydrophobia develops which makes

the patient feel fear for water. (5) Patient becomes delirious.

(6) Patient’s limbs become flaccid and they enter into spasm.

(7) If not treated in time, rabies can be fatal.

What is enteritis ? What are the main symptoms of this

disease ?

Ans. (1) The inflammation of the inner lining of the intestine

is called enteritis. (2) The infection is caused by bacteria, viruses,

worms, and chemicals or other harmful substances.

Symptoms of enteritis : (1) Severe pain in the stomach or

stomachache. (2) Fever and vomiting. (3) Loss of appetite.

(4) Diarrhoea or constipation. (5) Loss of weight.

What are the preventive measures of diarrhoea?

Ans. For preventing diarrhoea following preventive measures

are taken. (1) Giving oral rehydration therapy (ORT). (2) Using

boiled and cooled water for drinking. (3) Maintaining personal

hygiene and cleanliness. (4) Preventing dust, flies and other dirt

from settling on the food. (5) Keeping kitchen and cooking area

clean. (6) Washing fruits and vegetables clean before use.

What is AIDS? How is it caused ?

Ans. (1) AIDS means Acquired Immuno-deficiency Syndrome.

(2) AIDS is caused by Human Immuno-deficiency Virus or HIV.

(3) HIV infection makes the person lose the ability to resist other

diseases. (4) Since the immunity is lost, the person concerned

suffers from a variety of infections and contracts diseases

frequently.

*Explain the importance of personal and public

cleanliness.

Ans. (1) Contagious and communicable diseases spread fast if

personal and public hygiene is not maintained. (2) Defecating,

urinating in the open, spitting in public and such related

unhygienic practices can cause bacteria and viruses to spread far

and wide. (3) Tuberculosis germs spread through spittle. These

germs can reach healthy persons through air. (4) Uncovered and

unhygienic food can cause variety of gastrointestinal infections

such as enteritis, diarrhoea, typhoid, cholera, jaundice or hepatitis.

Flies, dirt and dust spread such germs at a very rapid pace. (5) In

order to avoid such infections and prevent the spread of epidemics,

it is most essential that everybody follows personal and public

cleanliness. (6) Some personal good habits like not spitting in the

open, using handkerchief while sneezing or coughing, not throwing

litter anywhere, not defecating and urinating in the open and not

consuming uncovered dirty food and water should be strictly

followed. (7) Keeping the environment clean will also improve

public cleanliness. Thus importance of personal and public cleanliness

is the essential factor in maintaining health of the society.

* Q. 2 What are the symptoms of the following diseases ?

(1) Polio (2) Cholera (3) Tuberculosis (4) Typhoid.

Ans. (1) Polio : (1) Fever (2) Red throat. (3) Strained

muscles of back and legs. (4) Weakness is felt in the arms and legs.

(5) Stunted growth of muscles. (6) Muscles become flaccid and lose

their structure developing disability.

(2) Cholera : (1) Severe diarrhoea and vomiting. (2) There is

dehydration due to loss of water from the body. (3) Skin becomes

dry and eyes become sunken. (4) There is severe pain in the

stomach (stomachache). (5) Cramps in the legs.

(3) Tuberculosis : (1) Constant cough. (2) There is

continuous low grade fever. (3) Blood in spittle. (4) Pain in the

chest region. (5) Difficulty in breathing. (6) Loss of weight.

(4) Typhoid : (1) Fever which lasts for a definite period.

(2) Rose-coloured rashes on the chest. (3) Diarrhoea. (4) Headache.

*  What measures can be taken to prevent the

following diseases ?

(1) Rabies (2) Chicken pox (3) Tuberculosis.

Ans. (1) Rabies : (1) First of all, the wound caused by the bite

of the animal should be flushed with soap and water. (2) Seeking

immediate medical help and treatment from a doctor. (3) Required

dosage of injections of anti-rabies should be taken from the doctor.

(4) All pet animals in the house should be given anti-rabies vaccine.

(2) Chickenpox : (1) Proper medical treatment should be

taken. (2) Care should be taken to avoid direct contact with the

patient suffering from chickenpox. (3) Children should be given

varicella vaccine which can prevent chickenpox infection.

(3) Tuberculosis : (1) BCG vaccine should be taken to

prevent tuberculosis. (2) Isolation of the patient should be done.

(3) Proper and thorough medical treatment should be given.

(4) Visiting a DOT centre and taking free medicines can help in

controlling tuberculosis.

4 What will you do if …

* (1) a person having cholera is to be given temporary but

immediate treatment.

Ans. The person having cholera may face danger of

dehydration. Therefore, he or she should be given oral rehydration

therapy immediately.

* (2) your friend has contracted chickenpox.

Ans. I will tell him to take proper medical treatment. If his

scabs on the blisters are falling off, he would be kept in isolation.

I will tell him to take enough and ample rest. All the things which

he uses will be kept separately. These things will be washed

properly.

* (3) the diet of a person convalescing after typhoid is to be

planned.

Ans. He will be given fresh, clean, nutritious and home-made

food which is easy to digest. He will be given pre-boiled and cooled

water for drinking.

* (4) a child in your class is an AIDS patient.

Ans. I will not ill-treat or shun him. I will give him a helping

hand allowing him to mix, play and study with all classmates.

(5) in your town pulse polio campaign is being held.

Ans. All the children below five years who stay in the vicinity

of our house would be taken for the dose of polio. Parents of such

children would be convinced to take their babies at the sites of polio

campaigns.

(6) your friend who is sharing your bench in school is

infected with scabies.

Ans. Our friend who has got scabies would be convinced to

take proper medical treatment. Direct contact with such a person

would be avoided till his skin infection is cured.

(7) your younger sister is bitten by a dog.

Ans. She will be pacified. The place of wound where dog has

bitten would be washed with germicidal soap and water. Then she

would be taken to the doctor for injections of anti-rabies vaccine.

The wound would be regularly and properly dressed under medical

supervision till it becomes alright.

(8) your neighbour’s baby is having severe diarrhoea.

Ans. The baby may get dehydration and it would be dangerous

for very young child. So immediately ORT (Oral Rehydration

Therapy) would be started. Later, we would accompany his parents

to go to the doctor. Proper medical treatment will be started for

the baby.

Q. 5 Write short notes on the following :

* (1) Dehydration (2) Oral Rehydration Solution

* (3) Vaccination (4) Pulse Polio Campaign.

Ans. (1) Dehydration : (1) Dehydration is caused due to

constant diarrhoea. (2) Dehydration causes body to become dry.

(3) It can be fatal for very young and weak children. (4) To make up

for the loss of water, patient is given Oral Rehydration Solution

(ORS). Later such a patient should be given proper medical

treatment.

(2) Oral Rehydration Solution : (1) Oral Rehydration

Solution is made up of sugar, salt and water in specific proportion.

(2) In case of dehydration, the patient is given this solution.

(3) When the person suffers from diarrhoea, then the intestinal

absorption is disturbed. (4) But the absorption of ORS solution

starts immediately and gives immediate relief to the patient.

(5) Giving ORS to the patient is called ORT or Oral Rehydration

Therapy. (6) If ORS is given to dehydrated young children, it can

prevent serious outcomes.

(3) Vaccination : (1) Diseases can be prevented by

vaccinations. Therefore vaccination is a preventive measure.

(2) Several vaccines are available for the prevention of different

diseases. Some vaccines are oral while others are injectable. (3) By

giving vaccination the resistance against diseases is increased.

(4) Vaccinations not only protects the people but also controls the

epidemics by checking the spread of diseases. (5) Health

department, therefore, undertakes vaccination campaign to

prevent the dangers caused by different diseases. (6) The

Government implements special vaccination programmes for

protecting young children. e.g. Pulse Polio Campaign. Children are

immunized against tuberculosis by giving BCG. They are also given

triple vaccine to provide protection against diphtheria, whooping

cough and tetanus.

(4) Pulse Polio Campaign : (1) Pulse Polio Campaign is the

programme undertaken by the National Department of Health.

(2) Under this campaign maximum number of children who are

below 5 years of age are given polio vaccine. (3) One day is

scheduled for entire India and all the children are given oral doses

of polio vaccine. (4) This helps to strengthen the resistance of the

children. (5) Two polio doses are given on two fixed days with an

interval of 6 weeks between them. These doses are known as booster

doses and are given in addition to the regular doses. (6) This

campaign is administered with the help of WHO and it is expected

that polio will be soon eradicated from our country.

Q. 6 Distinguish between the following :

(1) Polio and Rabies :

Ans. Polio Rabies

1. Polio spreads through

contaminated food, water

and minute particles in the

air.

1. Rabies is caused by the bite

of an infected animal like

dog, monkey or cat.

2. After the infection of polio,

strain is felt in the muscles of

back and legs.

2. After getting affected by

rabies, throat muscles

become rigid and get contracted.

3. Polio causes disability. 3. Rabies causes delirium.

4. All the children are given

polio doses as preventive

vaccine.

4. Anti-rabies vaccine is given

only if an infected animal

bites the victim.

(2) Typhoid and Tuberculosis :

Ans. Typhoid Tuberculosis

1. Typhoid is caused by

contaminated food and water

and is spread through house

flies.

1. Tuberculosis is caused by

bacteria which pass through

the spittle of the patient.

2. The infection of typhoid is

through food or water via the

mouth.

2. The infection of tuberculosis

is through air via the nose.

3. Typhoid affects stomach and

intestine.

3. Tuberculosis affects lungs

and chest.

4. There is fever for specific

period in typhoid.

4. There is continuous low

grade fever in tuberculosis.

8. DISEASES 107

5. There is stomachache and

headache in typhoid.

5. There is chest pain in

tuberculosis.

6. Vaccination for typhoid is

given at the time of suspected

epidemic.

6. BCG vaccination is given to

all at a young age only.

7 Give scientific reasons :

* (1) One should drink boiled water during epidemics.

Ans. (1) During epidemics, water is contaminated with

microorganisms causing diseases. (2) Diseases such as typhoid,

cholera, hepatitis, enteritis are caused on drinking such water.

(3) If water is boiled the disease causing microorganisms are killed.

(4) Thus in order to control the epidemics and to keep one’s health

safe, one should drink boiled water during epidemics.

* (2) People suffering from communicable diseases should

avoid going to public places.

Ans. (1) Communicable diseases spread when people share

space with a diseased person. (2) If people suffering from

communicable diseases go to a public place, they would spread the

disease causing germs in the air. (3) These germs can be

transmitted to other healthy persons. (4) If the resistance power of

the persons is less, they will fall sick by getting infected. (5) This

may break into an epidemic. Therefore, people suffering from

communicable diseases should avoid going to public places.

* (3) The wound caused by a dog bite should be flushed clean

with soap and water.

Ans. (1) Rabies is a viral disease caused due to virus present

in the saliva of an infected dog. (2) When such a dog bites and

causes a wound, the virus may enter the blood of the victim.

(3) This can cause infection of rabies. (4) However, if the wound is

immediately washed with soap, the virus may be destroyed.

(5) This is an immediate treatment to provide protection against

rabies. The wound caused by a dog bite therefore, should be flushed

clean with soap and water.

(4) Pet animals should be given anti-rabies vaccine.

Ans. (1) We keep animals like cats and dogs at home as pets.

(2) They may get infected with the virus of rabies. (3) If such an

infected pet bites us, we may also get rabies. (4) Rabies is a lethal

disease. (5) In order to protect the animals and to prevent rabies

being transmitted, they should be given anti-rabies vaccine.

(5) Tuberculosis is considered as the most communicable

disease.

Ans. (1) Tuberculosis is caused due to bacterial infection.

(2) It is an air-borne infection and spreads through the spittle of

T.B. patient. (3) When personal and public hygiene is not followed,

this disease spreads very rapidly. (4) It is estimated that every two

minutes, one patient dies of T.B. in India. Tuberculosis, therefore, is

considered as the most communicable disease.

(6) Food should always be covered. OR

One should never eat uncovered food.

Ans. (1) Uncovered food gets contaminated by dirt, dust, fine

partilces in the air and by many viruses and bacteria.

(2) Houseflies may carry germs of typhoid, cholera, diarrhoea and

contaminate the food. (3) Such food, if consumed can cause

diseases. (4) Variety of microorganisms can also spread an

epidemic through uncovered food. (5) To avoid all such infections,

we must always cover the food.

(7) ORS gives temporary relief to the patient of diarrhoea.

Ans. (1) In diarrhoea, due to loose motions the patient

becomes dehydrated. (2) The eyes get sunken and the mouth

becomes dry. (3) If immediate help is not given, the condition can

become critical. The absorption function of the intestine is

disturbed. (4) But by giving ORS, enough water, sugar and salt

enter the body saving the life of the patient. (5) The sugar and salt

in the ORS gets absorbed in the intestine and reduce the

dehydration. (6) However, for eradication of infection, proper

medical treatment is to be given, therefore, ORS gives only a

temporary relief to the patient of diarrhoea.

(8) Vaccines for many diseases are being prepared.

Ans. (1) It is always better to prevent disease than to cure or

give treatment. (2) Vaccination prevents diseases. (3) Vaccinating

a person strengthens his resistance power to fight against diseases.

(4) By giving vaccinations even the epidemics can be prevented.

(5) Vaccines therefore, have been prepared for different diseases.

Q. 8 Answer the following questions in one sentence

each :

(1) When do we show the symptoms of a disease ?

Ans. When our resistance to fight against a disease is weak,

we show the symptoms of a disease.

(2) Which is the disease that causes lifelong resistance

after its first infection ?

Ans. Chickenpox is the disease that causes lifelong resistance

after its first infection.

(3) Name the disease in which muscles become flaccid and

disability is caused.

Ans. Polio is the disease in which muscles become flaccid and

disability is caused.

(4) What is meant by booster dose ?

Ans. The vaccine dose which is given at specific intervals in

addition to regular dose is called booster dose.

(5) Which programme has been undertaken to eradicate

polio ? Who has started this programme?

Ans. National Department of Health of Government of India

has undertaken the pulse polio campaign to eradicate polio.

(6) Which vaccine is given to pets ?

Ans. Anti-rabies vaccine is given to pets.

(7) Who runs the campaign of Tuberculosis eradication ?

Ans. The World Health Organization runs the campaign of

Tuberculosis eradication.

(8) Which is the most easily communicable disease ?

Ans. Tuberculosis is the most easily communicable disease.

(9) What is freely available on DOT centres ?

Ans. Excellent medicines for tuberculosis treatment from the

World Health Organization are available freely at DOT centres.

(10) Which insect is responsible for the spread of cholera ?

Ans. The housefly is responsible for the spread of cholera.

(11) Which vaccination must be taken before travelling

or going abroad?

Ans. Before travelling or going abroad, vaccination against

cholera must be taken.

 (12) What is the inflammation of the inner lining of the

intestine called ?

Ans. The inflammation of the inner lining of the intestine is

called enteritis.

(13) What does dehydration mean?

Ans. Loss of water from the body due to continuous loose

motions, causing the body to dry up is called dehydration.

(14) Which diseases are prevented by the triple vaccine?

Ans. The diseases diphtheria, whooping cough and tetanus are

prevented by the triple vaccine.

(15) What does vaccination mean?

Ans. Vaccination means to increase the resistance of the body

against diseases.

(16) What does the acronym AIDS stand for ?

Ans. AIDS stands for Acquired Immuno-Deficiency Syndrome.

(17) What is the name of the virus that causes AIDS?

Ans. HIV or Human Immuno Deficiency Virus causes AIDS.

(18) Who discovered HIV?

Ans. French scientist Dr. Monteniere and American scientist

Dr. Gallo discovered HIV.

(19) Who started the worldwide AIDS control programme,

and when?

Ans. The world-wide AIDS control programme was started in

1986 by the World Health Organization (WHO).

Q. 9 Find the odd man out and give reasons :

(1) Cholera, Typhoid, Diarrhoea, Conjunctivitis.

(2) Cholera, Conjunctivitis, Scabies, Influenza.

(3) Scabies, Eczema, Ringworm, Polio.

(4) Polio, Tuberculosis, AIDS, Chickenpox.

(5) Diphtheria, AIDS, Whooping cough, Tetanus.

(6) Black magic, Witchcraft, Vaccination, Envy.

(7) Polio, Tetanus, Chickenpox, Enteritis.

(8) Delirium, Strain in the muscles of legs, Hydrophobia, Rigid

throat muscles.

(9) Dog, Rabbit, Cat, Man.

 (10) Fever for a definite period, Diarrhoea, Disability in

muscles, Rash on the chest.

Ans. (1) Conjunctivitis. All the other diseases cause loose

motions. (2) Scabies. Others are epidemic diseases. (3) Polio.

Others are contagious skin infections. (4) Tuberculosis. Others

are viral diseases. (5) AIDS. Others are diseases prevented by

triple vaccine. (6) Vaccination. Others are not related to proper

medical treatment. (7) Enteritis. Others are prevented in

childhood by vaccination. (8) Strain in the muscles of legs.

Others are symptoms of rabies. (9) Man. Others can cause rabies

by biting. (10) Disability in muscles. Others are symptoms of

typhoid.

Q. 10 Considering the correlation between the words of

the first pair, match the third word with the most appropriate

answer :

(1) Diarrhoea : Epidemic disease : : Eczema : ……… .

(2) Polio : Virus : : Tuberculosis : ……… .

(3) Edward Jenner : Small Pox : : Salk and Sabin : ……… .

(4) Strain in the back and leg muscles : Polio : : Rigid throat

muscles : ……… .

(5) Housefly : Typhoid : : Dog : ……… .

(6) Bacteria causing cholera : Vibrio cholerae : : Virus causing

AIDS : ……… .

(7) Tuberculosis : Communicable : : Scabies : ……… .

(8) Children below 5 years : Polio vaccine : : Travelling

abroad : ……… .

(9) Carrier of rabies virus : Dog : : Carrier of typhoid

bacteria : ……… .

(10) Enteron : Intestines : : Itis : ……… .

Ans. (1) Contagious disease (2) Bacteria (3) Polio (4) Rabies

(5) Rabies (6) HIV (7) Contagious (8) Cholera vaccine (9) Man

(10) Inflammation.

Q. 11 State whether the following statements are True or

False. If a statement is false, correct and rewrite it :

(1) All microorganisms can cause diseases.

(2) Many people from the same place get epidemic diseases

simultaneously.

(3) When a person gets a disease, his or her physical and

mental condition are disturbed.

(4) Communicable diseases are caused by direct contact.

(5) In polio, the muscles of the arms or legs become weak,

causing disability.

(6) The resistance acquired by chickenpox during first

infection remains lifelong.

(7) Every child under 5 years of age in India is given six doses

of polio vaccine with an interval of 2 weeks.

(8) By pulse polio campaign cholera from India would be

eradicated.

(9) Rabies can be fatal.

(10) Even incomplete inoculations can cure rabies.

(11) The WHO runs a tuberculosis eradication campaign.

(12) Enteritis causes loss of appetite.

(13) Fruits and vegetables should be washed before use.

(14) Diseases cannot be prevented by vaccination.

(15) Diseases can be caused due to anger of gods.

(16) ORS gives permanent relief.

(17) Dr. Monteniere is a scientist from Germany.

(18) Treatment can extend an AIDS affected person’s life

considerably.

(19) We should not extend helping hand to AIDS patient.

(20) Many diseases can be prevented by ensuring personal and

public cleanliness.

Ans. (1) False. All microorganisms do not cause diseases,

some are useful too. (2) True. (3) True. (4) False. Contagious

diseases are caused by direct contact. (5) True. (6) True. (7) False.

Every child under 5 years of age in India is given two doses of polio

vaccine with an interval of 6 weeks. (8) False. By pulse polio

campaign polio from India would be eradicated. (9) True.

(10) False. Incomplete innoculations cannot cure rabies.

(11) True. (12) True. (13) True. (14) False. Diseases can be

prevented by vaccination. (15) False. Diseases can be caused due to

microorganisms. (16) False. ORS gives temporary relief. (17) False.

Dr. Monteniere is a scientist from France. (18) True. (19) False.

We should extend helping hand to AIDS patient. (20) True.

Answer to the question given on page 75 of the textbook

* Which vaccine did Edward Jenner discover ? What

prompted this discovery ?

Ans. Dr. Jenner discovered the vaccine for smallpox.

It was prompted by the beliefs of some cowgirls regarding the

rash that appeared on their arms. This made the discovery of

vaccine.

Answers to the questions given on page 78 of the textbook

* (1) What instructions are given by the Health

Department during the rainy season ?

Ans. The Health Department gives the following

instructions : (1) Drink boiled water. (2) Take vaccines of

epidemic diseases. (3) Do not eat stale food or food left

uncovered. (4) If you fall ill, get medical treatment. (5) Do not

allow water to stagnate around the house.

* (2) Why should we drink boiled water during the

rainy season ?

Ans. (1) By boiling, the germs and microorganisms in

water are killed. (2) During rainy season, there are increased

chances of contamination of water. (3) By consuming such

water without boiling, many communicable and epidemic

disease infections could be caused. (4) In order to avoid

communicable and epidemic diseases, we should drink boiled

water during the rainy season.

* What must be done to maintain personal cleanliness ?

Ans. Personal cleanliness could be maintained in the

following ways :

 (1) Take a bath everyday.

(2) Do not defecate in the open. Wash hands cleanly with

soap after toilet.

(3) Use loose, clean and tidy clothes.

(4) Always eat fresh, hygienic and clean food.

(5) Filter and boil the water before drinking.

(6) Mouth should be rinsed clean and teeth should be

brushed with toothpaste or tooth powder. Brush your

teeth in the morning and before going to bed.

(7) Cut your nails regularly with nail cutter. Do not bite

nails and do not allow dirt to get accumulated in the

nails.

(8) Comb your hair neatly.

(9) Always keep away from bad addictive habits such as

smoking, gutkha, alcoholism.

(10) Exercise regularly.

* What will you do to keep the surroundings clean ?

Ans. (1) We will not throw garbage anywhere. We shall

dispose garbage in proper dustbins. Littering in the

surroundings will be prohibited. (2) No one will be allowed to

defecate, urinate or spit in the open. (3) Water accumulation

will be prevented. (4) Tree plantation will be done and the

surroundings will be beautified. (5) Flies, mosquitoes and

other nuisance-causing insects will be eradicated by using pest

control measures.

* Do we get AIDS by shaking hands with an AIDS

affected person ?

Ans. No, we do not get AIDS by shaking hands with an

AIDS affected person.

Q. 12 Fill in the blanks :

1. (1) Some ……… can do us harm.

(2) If our ……… to diseases is weak, we develop the symptoms

of the disease.

(3) Each disease has a specific ……… period.

(4) In disease of chicken pox ……… are formed on the boils.

(5) ……… doses are given in addition to regular one for

vaccination against polio.

Ans. (1) microorganisms (2) resistance (3) incubation

(4) scabs (5) Booster.

-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

2. (1) Give all pet animals in your house anti-……… vaccine.

(2) ……… discovered the bacteria which cause the disease

tuberculosis.

(3) For preventing infection from tuberculosis ……… vaccine

is taken.

(4) Cholera causes ……… in legs.

(5) Human beings are carriers of ……… bacteria.

Ans. (1) rabies (2) Robert Koch (3) BCG (4) cramps

(5) Vibrio cholerae.

-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --

3. (1) The inflammation of the inner lining of the intestine is

called ……… .

(2) The body becomes dry because of loss of water due to

……….

(3) The vaccine against diphtheria, whooping cough and

tetanus is called ……… .

(4) Infection by ……… causes AIDS.

(5) In 1986, AIDS control programme was started worldwide by

……… .

Ans. (1) enteritis (2) diarrhoea (3) triple vaccine (4) HIV

(5) WHO.

Q. 13 Fill in the blanks by choosing the correct

alternative and rewrite the completed statements :

(1) A ……………… is a nation’s resource.

(a) wealth, money (b) smiling children

(c) healthy society (d) sick people

(2) Diseases caused due to germs entering the healthy person’s

body through the air are called ……… diseases.

(a) communicable (b) contagious (c) skin (d) throat

(3) Scabies and eczema are ……… diseases.

(a) communicable (b) contagious

(c) epidemic (d) muscular

(4) The resistance acquired after getting ……… is lifelong.

(a) jaundice (b) cholera (c) diarrhoea (d) chickenpox

(5) In disease of ……… the muscles become flaccid and

disability is caused.

(a) polio (b) chickenpox (c) AIDS (d) tuberculosis

(6) In disease of ……… throat muscles become rigid and

contracted causing severe pain.

(a) AIDS (b) diarrhoea (c) rabies (d) typhoid

(7) Tuberculosis is considered as most ……… disease.

(a) painful (b) communicable (c) sensitive (d) contagious

(8) Excellent medicines for the treatment of T.B. are available

at ……… centres.

(a) rural (b) DOT (c) Government (d) urban

(9) Cholera spreads through water or food contaminated due to

……… .

(a) dogs (b) cats (c) houseflies (c) mosquitoes

(10) If there is dehydration, oral ……… solution should be

immediately given.

(a) dehydration (b) rehydration (c) sugar (d) salt

(11) In cases of diarrhoea, the………functions of the intestine is

disturbed.

(a) structural (b) absorptive (c) primary (d) digestive

(12) Each one of us must co-operate with………by taking care of

ourselves.

(a) Health department (b) Government officers

(c) medical doctors (d) family members

8. DISEASES 117

(13) AIDS patient loses its ability to ……… .

(a) learn new things (b) sense the emotions

(c) earn his income d) fight with the diseases

(14) In ……… the National AIDS Control Programme was

started in India.

(a) 1986 (b) 1987 (c) 1990 (d) 1997

(15) Through ……… excellent medicines are available in

government hospitals free of cost.

(a) HIV (b) DOT (c) WHO (d) AIDS

Ans. (1) healthy society (2) communicable (3) contagious

(4) chickenpox (5) polio (6) rabies (7) communicable (8) DOT

(9) houseflies (10) rehydration (11) absorptive (12) Health

Department (13) fight with diseases (14) 1987 (15) WHO.

Q. 14 Match the following :

[1] ‘A’ ‘B’

(1) Edward Jenner

(2) Robert Koch

(3) Monteniere and Gallo

(4) Salk and Sabin

(a) HIV

(b) Vaccine for Smallpox

(c) Polio Vaccine

(d) Tuberculosis bacteria

Ans. (1) Edward Jenner – Vaccine for Smallpox (2) Robert

Koch– Tuberculosis bacteria (3) Monteniere and Gallo –HIV

(4) Salk and Sabin – Polio Vaccine.

[2] ‘A’ ‘B’

(1) World Health Organization

(2) Tuberculosis Eradication Campaign

(3) Virus causing AIDS

(4) Acquired Immuno Deficiency

Syndrome

(a) DOT

(b) HIV

(c) AIDS

(d) WHO

Ans. (1) World Health Organization –WHO (2) Tuberculosis

Eradication Campaign–DOT (3) Virus causing AIDS–HIV

(4) Acquired Immuno Deficiency Syndrome– AIDS.