ICSE/GRADE 9/ DISEASE FULL NOTES

DISEASES

Disease is a departure from normal health through structural or functional disorder of the body

World health day- april 7

Classification of diseases

Based on occurrence

endemic	epidemic	Pandemic	sporadic
Disease is localized and affect only few Ex- yellow fever- African countries Goiter- Himalayan region	Disease break through the large areas and spreads from place to place Ex- plague in india Small pox	Disease id spread out world wide Ex- AIDS	Scattered individual cases Ex- malaria Cholera

Based on communicability

Communicable/infectious	Non communicable/ non infectious
Germs spread from person to person through air, water, wind=infection Disease causing agent- pathogen Ex- cold, cough Incubation period-After the infection till the time of appearance of the first symptom	Does not spread from one person to another Ex- diabetes, blood pressure

kINDS OF PATHOGEN- bacterial/ viral...

kinds of transmitting agent- water- borne, food borne......

Classification of non infectious disease-

Nutritional deficiency	Beri beri, night blindness
Metabolic	Diabetes
Genetic	Haemophilia
Allergies	Asthma
Degenerative/ ageing	Arthritis
Physical/chemical	Injuries, radiation
Mental illness	Depression
Cancer	Abnormal division of the cell, caused by carcinogenic agents

INFECTIOUS DISEASES-Infections are caused due to certain micro-organisms called pathogens.

Viruses	Polio, mumps, rabies
Rickettsiae	Typhus fever
Bacteria	Typhoid, tetanus
Moulds /fungi	Ring worm
Protozoan	Dysentery
Worms	Pin worm
Mites	scabies

TRIPLE VACCINE- is a combined vaccine given by injections to the young babies to protect them from the 3 diseases-tetanus, diphtheria, pertussis

CHARACTERISTICS OF VIRUSES- a. very small substances               b. visible in electron microscope                               3. Live only in living cell, outside they are particle like           4. Take over the metabolism of host and reproduce to prepare many copies                       5. It can be crstallised and stored in jars                 6. Highly specific              

BACTERIAL DISEASES, PARASITIC WORMS, VIRAL DISEASES

disease	Affected organ	organism	Incubation period	symptoms	antibiotic	prevention	others
tuberculosis	Lung disease	Rod shaped bacterium Mycobacterium tuberculosis	2-10 weeks	Tissue form a tubercle round the germs	streptomycin	BCG	24 march anti tuberculosis day
cholera	Intestinal tract	Vibrio cholerae	Few hrs -6 days	Vomiting, loose stools, dehydration	ORS Saline	Good sanitation Clean and hygienic food Well cooked food Avoid insect contact	Oro-faecal contamination
Tetanus/lock jaw diseases	Complete body, jaw gets locked	Clostridium tetani	4-20 days	Jaw gets locked	Tet vac	vaccination	Organism enters the body thro deep cuts
syphilis		SEXUALLY TRANSMITTED DISEASE
TRIPLE VACCINATION
Common roundworms Ascaris ascariasis	Intestines- Female lays 1000 eggs per day					Washing hands and fruits, veggies b4 eating	Cylindrical worm, llr to earthworm size,female longer, male have cureve hook
Tapeworm/taenia solium/taeniasis	intestine			Increases in length Absorbs host food. The mature worms throw the eggs by detaching from the body and comes out through feaces			Eating infected pork/beef
polio	Legs	Polio virus- spreads through  secretion of nose, throat, intestinal wastes	7-14 days	Paralysed joints	Salk vaccine- developed from killed virus		Pulse poliuo programme- oral drops
mumps	Neck and salivary glands		12-26 days	Swollen neck Parotid glands are affected		Isolation for 7-10 days, separate utensils and clothing
rabies	Central nervous system	Spreads through mad dog bite-polio virus	More than a month	Hydrophobia- scared for water		Regular injection of the weakened organism	s
HIV-human immune deficiency virus causes AIDS	Immune system	HIV	10-12 years	Cancers, fever, weight loss-secondary diseases			Spreads through sexual intercourse Contaminated blood transfusion Mother to child transmission needles