This document summarizes several human diseases caused by bacteria: 1) Streptococcal diseases like strep throat and necrotizing fasciitis can be caused by Streptococcus bacteria. Typhoid fever is caused by Salmonella typhi bacteria. 2) Cholera results in severe diarrhea and dehydration from Vibrio cholerae bacteria. Clostridium tetani bacteria cause tetanus through toxin production. 3) Mycobacterium leprae bacteria lead to leprosy, affecting nerves and skin. Tuberculosis is caused by Mycobacterium tuberculosis, which forms lesions in the lungs.

1. HUMN DISEASES CAUSED BY BACTERIA-
STREPTO COCCAL DISEASES, TYPHOID,
CHOLERA, TETANUS, LEPROSY,
TUBERCULOSIS AND PNEUMONIA
SASNA

2. CONTENTS
STREPTO COCCAL DISEASES
TYPHOID
CHOLERA
TETANUS
LEPROSY
TUBERCULOSIS
PNEUMONIA

3. STREPTO COCCAL DISEASES
STREPTOCOCCI
1. Non motile cells, spherical ,ovoid ,occurring in pairs
short or long chains
2. Gram positive ,facultative aerobes
3. Capsules are not regularly formed
4. Found in mouth and intestine of man and other animals ,in dairy
Product and in fermenting plant juices
5. Some species are highly pathogenic

4. Mainly two types
1. Group A streptococcus (GAS)
2. Group B streptococcus (GBS)
GAS (GROUP A STREPTOCOCCUS)
1. It can cause wide range of infections
2. People also carry group a streptococci in the throat ,skin, and have no
symptom of illness.
3. Most GAS infections are relatively mild illness such as strep throat, or
impetigo ( a skin infection)
4. Also cause necrotizing fasciitis or streptococcal toxic shock syndrome

5. NECROTIZING
FASCIITIS
1. Severe pain and swelling ,often
rapidly incresing
2. Fever
3. Redness at a wound site
STREPTOCOCCAL
TOXIC SHOCK
SYNDROME
1. Severe pain in arms and legs
2. Dizziness
3. Flu like symptoms fever ,chills,
Muscle aches ,nausea,vomiting
4. Confusion
5. A flat red rash over large area’s
Of the body
ANTIBIOTIC THERAPY IS THE MAIN WAY TO PREVENT INFECTION

6. GROUP B STREPTOCOCCUS
• Strep B is harmless in adults ,in newborns it can cause a serious
Illness known strep B diseases
•Group b can also cause serious cause in adults with certain chronic
medical conditions. Such as
1. Diabetes
2. Liver disease
•At pregnant condition group b strep screening test during
Third trimester is necessary because other wise if affect the baby

7. In infants illness caused by GBS can two forms
• early onset
• late onset
Early onset group B strep disease
1. Sick with in on week after birth
2. Fever
3. Difficulty feeding
4. Lethargy
Late onset group b strep disease
1. Sick with in a week to a few months after birth
2. Difficulty breathing
3. Fever
4. Difficulty feeding
5. Lethargy
6. Irritability

8. Strep B infection can lead to life threatening
Complications in infants including
1. inflammation of the lungs (pneumonia)
2. inflammation of the membrane and fluid
surrounding the brain and spinal cord (meningitis)
3. infection in the bloodstream (bacteremia)

9. ADULTS
•Strep B affect bowel ,vagina, rectum,
bladder, or throat
In adults it cause complications like :
1. Skin infections
2. Sepsis ( infection of blood stream)
3.Urinary tract infection
4. Inflammation of lungs
5. Bone and joint infections
6. Infection of heart valves
7. Meningitis

10. •Pregnant women ,group B strep cause
• Urinary tract infection
• infection of placenta and amniotic fluid
• inflammation & infection of the membrane
• lining the uterus
• Infection of bloodstream (sepsis)

11. Some other diseases
Rheumatic fever : In children by the repeated infection of the
respiratory tract, fever, pain in the joints,
the products of streptococcus metabolism
are the cause of the symptoms
Septic sore throat: Infection of the tonsils and lymph nodes,
accompanying fever
Septicemia : Improper treatment of flesh wounds and if
the blood poisoning is allowed to progress,
Death may follow

12. TYPHOID FEVER
•The causal organism salmonella typhi
•It is a gram negative rod that is very resistant to environmental
Condition
•It may remain alive for long periods in fresh water and foods
•The chief source of disease is the human carrier
•The recovered patients may continue to harbour bacteria which
are shed in the feces for long periods
•Typhoid mary (1906) demonstrated this fact.
•Contaminated sewage is another source .
•When it mixes with drinking due to broken sewer lines or natural
disasters, epidemic may follow
Salmonella typhi

13. •Flies also transport bacteria from sewage to food or water
•This bacterium is acid resistant it passes through stomach and enter
small intestine, where multiply quickly.
•It produce deep ulcers ,constipation, and bloody stools these are the
Indication of bacterial penetration to blood vessels of intestinal walls
•Fever rises gradually ,and skin covered with bright red rose spots
•Disease was previously treated with chloramphenicol.
•At present amoxicillin and sulfam ethoxazole trimethoprim have
been substituted

14. •The bacterium have some preferences for gallbladder ,
and antibiotics are not effective in this organ
•In such cases gallbladder is removed.
•Chemically killed bacteria are used in the vaccine for typhoid
fever with about 100,000 dead organisms in each dose
•The organism may also be identified by isolating it from urine,
blood, stool or Bone marrow cultures
•In 1896 fernand widal devised the Widal test
•It is a aggultination method in which typhoid fever antibodies
are detected by Mixing the patients serum with salmonella
cells and observed for clumping

15. THESE DAYS EXTRACT OF FLAGELLA OR
CELLULAR ANTIGENS OF BACTERIUM RATHER THAN
CELLS ARE USED FOR THIS TEST

16. CHOLERA
•These is severe dysentery , vomiting and violent cramps with
much Loss of fluid
•Eyes become shrouded in grey and sink in to orbits skin
become dry ,wrinkled and cold and muscular cramps occur in
the arms and legs .
•There is continuous thirst but patient is unable to hold fluid
•The blood is thickened and urine production stops
•Without urine metabolic wastes accumulate and tissue suffer
toxic damage
•The sluggish blood flow to the brain stops oxygen to this vital
organ and person enters into coma and soon dies
Vibrio cholerae

17. •The causal organism ,vibrio cholerae .
•A gram negative rod was first cultivated by robert koch in
1883 the bacterium has two recognised biotypes
1.Classical V.Cholerae
2.EI. Tor biotype
•EI Tor type produces a haemolysin that disrupt sheep red
blood cells, but classical biotype does not .
•The EI tor also exists in carriers, not found in classical forms
• Bacteria enter gastrointestinal system in large number since
Stomach acid kills most of the bacteria
• The surviving organisms enter the intestine and move about
through
the mucous coating, adhere strongly in tissues and produce
powerful toxins

18. •The toxins consist of 3 chains of protein that stimulate the production
of the enzyme, adenyl cyclase
•This enzyme increase the level of adenosine monophosphate (AMP)
which lead to abundant secretion of fluid by the intestine.
•The presence of infection also retards water absorption through the wall
•The critical treatment is to restore water balance in the body
•Intravenous injection of tetracyclin are useful to control bacteria
•Immunization with preparation of dead bacteria provides protection for
about six months.
•Prevention method include sanitation, personal hyegine, and care in
food preparation

19. TETANUS
•It is a soil borne disease ,most dangerous of human disease
•The bacterium clostridium tetani exist in air ,water, animal and human
Intestine and especially the soil
•The bacteria enter a wound in very small numbers and produce second
Most powerful toxin to science
•The toxins provoke sustained and uncontrolled contraction of the muscle
and spasms occur throughout the body
•The patients experiences a violent death
•The bacterium exist as spores in the intestine of many animals and man
•The organism is excreted in the feces to the soil , from where spores are
Introduced to the anaerobic environment of dead necrotic tissue in
deep puncture.

20. Clostridium tetani

21. •The symptoms develop rapidly ,with in hours of entry ,
the spores revert to vegetative cells which produce several
Toxins including Tetanospansmin
•Tetanospansmin is a high molecular weight protein
•It spread through the blood stream and along the axons of
the nerve cells to the nerve endings where it inhibits the
removal of acetocholine in synapse
•Muscle contraction occur -------- muscle stiffness ----- back
Arches -----jaws clench----- and a fixed smile on face ----
this disease is called lock jaw
•Immunisation to tetanus may be achieved by injecting toxoid
Consisting of formaldehyde treated toxin that is
Precipitated with alum

22. LEPROSY ( HANSEN’S DISEASE )
•This is a contact disease
•It degenerate the tissues and deforming the body
•There is a long incubation period of 3 to 6 years during which victims
are not easily identified
•The causal organism is mycobacterium leprae ,a heat sensitive
Organism which prefer nerves and cutaneous tissues
•Never effect internal oragn
•Mainly 2 type
•1.Lepromatous leprosy :1. Tumour like growths called lepromas on
Skin and along respiratory tract.
2. Patches of infection occur on hands
And feet
3. Skin lose pigmentation

23. •2. Tuberculoid leprosy : 1. Involves superficial nerves
2. Undergoes muscle atrophy
3. Disfiguring of skin and bones, twisting of limbs’
Curling of fingers to form a characteristic claw
hand
4. Nasal cartilage and outer ear tissue degenerate
•Mycobacterium leprae first observed in 1874 by Gerhard Hansen that's why
This organism also known as Hansen's bacillus and the disease
Hansen's disease
•The BCG used for immunisation
•Antibiotic as rifampin ,clofazimine, and some sulfone drugs dapsone is also
used
•There is a rapid screening test called the lepromin test or mitsuda reaction
•Extract from lepromatous tissue is taken and test performed according to it

24. Mycobacterium leprae
Gerhard Hansen

25. TUBERCULOSIS
•The causal organism is a small rod that enter respiratory tract and
grow on lung tissue
•Symptoms are chronic cough ,chest pain, high fever, and flow of thick
expectorated matter called sputum
•Latter sputum may be rust coloured if the blood has enter the lung
cavity
•The incubation period 2-10 weeks for the primary infection.
•In the infected lungs cells of macrophages ,leukocytes, and t lymphocyte
Surrounds the parasite ,and due to deposition of calcium salts and
Fibrous materials, a hard nodule tubercle is formed
•Tubercles may be visible in the patients chest x –ray

26. Tubercles may break apart and spread
bacteria to liver , bone , and kidneys
This disease then called
military tuberculosis

27. BOVINE TUBERCULOSIS
Causal organism mycobacterium bovis
The organism transmitted through milk
•BACILLE CALMETTE GUERIN (BCG) is a preparation of attenuated
strain of M.Bovis is used in immunisation programmes through out
the world
•It is named for Albert calmette and Camille Guerin who developed it
in the 1920s

28. PNEUMOCOCCAL PNEUMONIA
•The word pneumonia in abroad sense includes a number
of microbial diseases of the bronchial tubes and lung
Tissues
•About 90% bacterial cases are caused by gram positive
diplococcus
•Diplococcus having a capsule and a lancet like pointed
ends
•This organism is commonly known as pneumococcus ,
it is described as Streptococcus pneumoniae

30. •The destruction of alveolar walls ,blood seep in to lung
Spaces and rust coloured sputum expelled ,if entire lobe of
Lung is involved it is called lobar pneumonia
•If both sides are infected ,it is called double pneumonia
•Scattered patches of infection in bronchial tree yield
Bronchoneumonia
•The bacterium produces several virulence factor
Hemolysin , leukocidin and hyaluronidase
•Due to the presence of capsule it resist phagocytosis

31. COMMON DRUGS AVAILABLE