1. H E A L T H A N D
D I S E A S E

2. A c c o r d i n g t o t h e W o r l d H e a l t h
O r g a n i z a t i o n ( W H O ) ,
h e a l t h i s a s t a t e o f c o m p l e t e p h y s i c a l ,
m e n t a l a n d s o c i a l w e l l - b e i n g .
A d i s e a s e i s a n a b n o r m a l c o n d i t i o n
a f f e c t i n g t h e b o d y o f a n o r g a n i s m . I t i s
o f t e n a s s o c i a t e d w i t h
s p e c i f i c s y m p t o m s a n d s i g n s .

3. T Y P E S O F D I S E A S E S
T h e r e a r e t w o t y p e s o f d is e a s e s : in f e c t io u s a n d n o n - in f e c t io u s .
N o n - i n f e c t i o u s d i s e a s e s a r e n o t
c a u s e d b y m i c r o o r g a n i s m s , s o
t h e y a r e n e v e r c o n t a g i o u s .
T h e y c a n b e h e r e d i t a r y o r c a n b e
r e l a t e d t o :
- a g e ( l i k e o s t e o p o r o s i s ,
A l z h e i m e r 's d i s e a s e , c a t a r a c t s )
- n o n - h e a l t h y w a y s o f l i f e , l i k e
d r u g s o r a l c o h o l c o n s u m p t i o n ,
s m o k i n g o r l a c k o f p h y s i c a l
e x e r c i s e ( s u c h a s c a n c e r s , s t r o k e
a n d p u l m o n a r y o r c a r d i o v a s c u l a r
d i s e a s e s ) .
I n f e c t i o u s d i s e a s e s a r e
c a u s e d b y p a t h o g e n i c
m i c r o o r g a n i s m s , s u c h a s
b a c t e r i a , v i r u s e s , p a r a s i t e s o r f u n g i .
I f t h e d i s e a s e c a n
b e t r a n s m i t t e d
f r o m o n e p e r s o n
t o a n o t h e r, i t i s
c a l l e d a
c o n t a g i o u s
i n f e c t i o u s
d i s e a s e .
I f t h e d i s e a s e c a n 't
b e t r a n s m i t t e d , i t
i s c a l l e d a n o n -
c o n t a g i o u s
i n f e c t i o u s d i s e a s e .

4. NON INFECTIOUS DISEASES
Illness:
1. Congenital: exist at birth.
2. Hereditary: from parents.
3. Deficit: abscence of any substance.
4. Chronic: prolonged and no possible cure.
5. Autoinmmune
6. Aging
Any disease may belong to 2 or more groups.

5. W A Y S O F T R A N S M I S S I O N O F C O N T A G I O U S
I N F E C T I O U S D I S E A S E S
A c o n t a g io u s in f e c t io u s d is e a s e c a n b e t r a n s m it t e d t h r o u g h
t w o w a y s o f t r a n s m is s io n :
I n t h e d ir e c t t r a n s m is s i o n ,
t h e p a t h o g e n p a s s e s
d i r e c t l y f r o m a n i l l p e r s o n
t o a h e a l t h y o n e , b y d i r e c t
c o n t a c t , s n e e z e , c o u g h , e t c .
I n t h e in d i r e c t t r a n s m is s io n ,
t h e p a t h o g e n u s e s v e h i c l e s o r
v e c t o r s t o p a s s f r o m o n e
p e r s o n t o a n o t h e r. T h e s e
v e c t o r s c a n b e w a t e r , f o o d o r
a n i m a l s .

7. S T A G E S I N IN F E C T I O U S D I S E A S E S
T h e r e a r e t h r e e s t a g e s i n i n f e c t i o u s d i s e a s e s :
1
T h e i n c u b a t i o n p e r i o d i s
t h e t i m e b e t w e e n t h e
i n f e c t i o n a n d t h e
a p p e a r a n c e o f s y m p t o m s .
S o m e d i s e a s e s h a v e a
l a t e n c y p e r i o d , i n
w h i c h t h e p a t h o g e n h a s
i n f e c t e d t h e b o d y , b u t i t
r e m a i n s i n a c t i v e a n d
c a n 't b e t r a n s m i t t e d t o
o t h e r p e o p l e .
2
D u r i n g t h e a c u t e p e r i o d t h e
s y m p t o m s o f t h e d i s e a s e o c c u r.
3
T h e c o n v a l e s c e n c e p e r i o d i s
t h e t i m e w h e n t h e p a t h o g e n s
a r e e l i m i n a t e d , t h e s y m p t o m s
d i s a p p e a r a n d t h e p e r s o n
r e c o v e r s a g a i n .

8. Epidemics and pandemics:
When an illness is very extended:
 Epidemic affects a city or a country.
 Pandemic affect to a continent or the world.
Fighting against illnesses:
 Treatment with drugs.
 Surgical operations.
 Preventive medicine: vaccines.

9. T h e i m m u n e s y s t e m i s a s y s t e m o f b i o l o g i c a l s t r u c t u r e s a n d
p r o c e s s e s w i t h i n a n o r g a n i s m t h a t p r o v i d e s im m u n it y , i .e .,
p r o t e c t s u s a g a i n s t p a t h o g e n s .
T h i s r e s p o n s e t o p a t h o g e n s i s t h e i m m u n e r e s p o n s e .
T h e r e a r e t w o t y p e s o f i m m u n i t y :
I n n a t e i m m u n i t y ,
O u t e r d e f e n s e s o r b a r r i e r s . T h e y p r e v e n t p a t h o g e n s f r o m
e n t e r i n g t h e b o d y .
T h e in f la m m a t o r y r e a c t i o n . M a c r o p h a g e s
A d a p t i v e o r a c q u i r e d i m m u n i t y
L y m p h o c y t e s . A n t i b o d i e s
T H E B O D Y ' S D E F E N S E S

10. ILLNESS
Illness caused by viruses:
a) Common cold: discomfort, nasal
secretions, congestion. Not fever.
Trasmitted by air.
b) Flu: Similar symptoms.
c) AIDS: HIV virus. Attacks defence system.
 No medicines against viruses. Antibiotics for bacterias.
 Drugs against symptoms.

11. ILLNESS
Illness caused by bacterias:
More resistant than viruses. Examples:
a) Salmonella: contaminated foods.
High fever and digestive disorders.
b) Tetanus: rusted metals, caused by
Chlostridium tetani. Affects to
nervous systems.
Treated by antibiotics, that kill or
prevent growth of bacterias.

12. ILLNESS
Illness caused by fungi:
 Very contagious, related to lack of
hygiene. Not serious, difficult for cure.
 Examples: Candidiasis and Athlete´s foot.
Illness caused by protozoa:
 Common in tropical regions.
 Malaria or paludism caused by
Plasmodium. By mosquito.
 Sleeping sickness caused by
Trypanosoma. By tse-tse fly.

13. C H E M I S T R Y I N D I S E A S E . V A C C I N E S
W e c a n g e t a r t i f i c i a l i m m u n i z a t i o n b y
u s i n g v a c c i n e s . T h e y c a n p r e v e n t a d i s e a s e
f r o m o c c u r r i n g .
T h e y c o n t a i n k i l l e d o r i n a c t i v e p a t h o g e n s
o r s o m e o f t h e i r p r o d u c t s , s u c h a s t o x i n s
o r s u r f a c e p r o t e i n s , s o t h a t a p r i m a r y
i m m u n e r e s p o n s e c o m e s o u t a n d l o n g - l i v e d
m e m o r y c e l l s f o r t h e v i r u s o r t h e b a c t e r i a
a r e c r e a t e d .
T h i s w a y , t h e n e x t t i m e t h e p a t h o g e n e n t e r s
t h e b o d y , a s e c o n d a r y i m m u n e r e s p o n s e
w i l l l a u n c h o u t a n d i t w i l l n o t c a u s e a n y
d i s e a s e o r t h i s w i l l b e m i l d e r.

14. C H E M I S T R Y I N D I S E A S E . M E D I C I N E S
I f a d i s e a s e h a s b e e n p r o v o k e d b y b a c t e r i a , i t c a n b e
f o u g h t b y a n t i b i o t i c s , w h i c h k i l l b a c t e r i a o r p r e v e n t
t h e m f r o m m u l t i p l y i n g .
A n t i v i r a l s c a n d e s t r o y v i r u s e s , b u t t h e y a r e n o t a s
e f f e c t i v e a s a n t i b i o t i c s a r e a g a i n s t b a c t e r i a .
O n c e a d i s e a s e h a s s t a r t e d , i t m a y b e f o u g h t b y u s i n g m e d i c i n e s .
S e r u m i s a c h e m i c a l m i x t u r e t h a t c o n t a i n s a n t i b o d i e s f o r a p a t h o g e n o r
a t o x i n . I t i s u s e d w h e n a n t i b i o t i c s o r a n t i v i r a l s a r e n o t e f f e c t i v e , a s i t
o c c u r s w h e n t h e d i s e a s e i s n o t p r o v o k e d b y t h e p a t h o g e n d i r e c t l y , b u t
b y i t s t o x i n s ( l i k e t e t a n u s ) o r i n c a s e s o f i n t o x i c a t i o n o r a n i m a l b i t e s
( s n a k e s , s p i d e r s )
O t h e r m e d i c i n e s c a n r e l i e v e t h e s y m p t o m s o f a d i s e a s e , b u t t h e y c a n n o t
c u r e i t .

15. ILLNESS. CANCER
Cancer:
 Alteration in the division of cells: rapidly and uncontrolled 
tumor  cancer.
 Detecting: blood analysis, X-rays, scanners.
 Metastasis: spreading of cancer. Failure in organs.
 Fight: chemotherapy and radiotherapy.
 Prevention: hereditary factors + carcinogens.