The document discusses various infectious diseases including meningitis, typhoid fever, leprosy, tuberculosis, urinary tract infections, AIDS, syphilis, gonorrhoea and their causes, symptoms, transmission and treatment. Meningitis can be caused by bacteria, viruses or fungi and symptoms include fever and inflammation of the membranes surrounding the brain and spinal cord. Typhoid fever is caused by Salmonella typhi bacteria and spreads through contaminated food or water. Leprosy is caused by Mycobacterium leprae and results in skin lesions and nerve damage.

1. UNIT - V
Prepared by
Padmaja V
Asst. Prof.
FCP, SBMCH.

2. INFECTIOUS DISEASE
 MENINGITIS
 It is an inflammation of brain and spinal cord membranes
(meninges).
 Meningitis can occur when fluid surrounding the meninges
becomes infected.
 The most common causes of meningitis are viral and bacterial
infections, but can also be cancer, chemical irritation, fungi
and drug allergies.
 They can be transmitted by coughing, sneezing or close
contact.

3. VIRAL MENINGITIS
 Eg- coxsackievirus A
 Coxsackievirus B
 Echoviruses
 Westnile virus
 Influenza
 Mumps
 HIV
 Measles
 Herpes viruses
 coltivirus

4. BACTERIAL MENINGITIS
 Streptococcus pneumoniae – pneumococcal meningitis
 Neisseria meningitides – meningococcal meningitis
 Haemophilus influenza
 Listeria monocytogenes

5. PATHOPHYSIOLOGY

8. TREATMENT
 Antibiotics
 Corticosteroids to reduce fever
 Oxygen therapy for patients having breathing
trouble.

9. TYPHOID FEVER
 It is also called as enteric fever.
 It is an acute infectious illness associated with fever that
is most often called as Salmonella typhi bacteria.
 The bacteria are deposited through fecal contamination in
water or food by a human carrier and are then spread to
other people in the area.

11. PATHOPHYSIOLOGY

15. LEPROSY
 It is also known as Hansen’s disease.
 It is an infection caused by slow-growing bacteria called
Mycobacterium leprae or M.lepromatosis.
 It is slowly developing from 6 months to 40 years,
progressive disease that damages the skin and nervous
system.
 It results in skin lesions and deformities.

17. PATHOGENESIS
 It affects nerves, skin and eyes. It may also affect the
mucosa (mouth, nose and pharynx), testes, kidney,
voluntary smooth muscles, RES and vascular
endothelium.
 Bacilli enter the body usually through respiratory system.
 It migrate towards the neural tissue and enter the
schwann cells.
 It can also found in macrophages, muscle cells and
endothelial cells of blood vessels.

22. TREATMENT

23. TUBERCULOSIS
 There are many subgroups in the genus mycobacterium
such as M.aviumintracellulare, M.kansasii, M.bovis but
M.tuberculosis alone is pathogenic in human.
 M.tuberculosis most commonly affects the lungs.
 It is transmitted from person to person via droplets from
the throat and lungs of people with the active respiratory
disease.
 Most commonly, tuberculosis is caused by air-borne
infection.

24. ETIOLOGY
 It is caused by Mycobacterium tuberculosis, which
spread from person to person through microscopic
droplets released in to air.
 This can happen when someone with the untreated active
form of tuberculosis, coughs, speaks, sneezes, spits,
laugh or sings.

30. URINARY TRACT INFECTION
 UTI is a bacterial infection involving the kidneys, ureters,
bladder or urethra.
 An infection affects the lower urinary tract (urethra or
bladder) it may be called as urethritis or cystitis, if it only
affects the bladder.
 If it migrates to and affects the upper urinary tract
(ureters or kidney) it is called ureteritis and if it affects
just the kidneys, it is called pyelonephritis.

31. ETIOLOGY

32. PATHOPHYSIOLOGY

34. SIGNS AND SYMPTOMS

36. AIDS
 Acquired Immunodeficiency Syndrome – is a chronic
potentially life threatening condition caused by the human
immunodeficiency virus (HIV).
 By damaging immune system, HIV interferes with body’s
ability to fight against the organisms that cause disease.
 AIDS – CD4+ T cells count below 22 cells per micro liter
or the occurrence of specific disease in association with
an HIV infection.

37.  Virus can be isolated from body fluids, blood, semen,
vaginal secretion, saliva, breast milk, tears, urine, CSF,
peritoneal fluid.
 Important cause of infection is unsafe sexual intercourse,
sharing unsterilized needles, blood and blood products.

38. HIV STRUCTURE

39. PATHOPHYSIOLOGY

46. SYPHILIS
 It is STI (sexually transmitted infection) caused by the
spirochete bacterium Treponema pallidum.
 This disease can be passed to another person through
close physical contact.
 The infected person is often unaware of the disease and
unknowingly passes it on to his or her sexual partner

47. STAGES OF SYPHILIS
 Primary syphilis (stage 1) – symptoms begins with
painless but highly infectious sore on the genitals
(penis, vagina, anus, rectum, tongue or lips) or
sometimes around the mouth.
 Symptoms appear any time from 10 days to three months
after exposed to infection.
 It lasts for two to six weeks before disappearing.

48.  Secondary syphilis (stage 2) – skin rashes and sore
throat develop.
 These symptoms may disappear within a few weeks,
after which person may experience latent (hidden) phase
with no symptoms, which can last for years.

49.  Tertiary syphilis (stage 3) – people who are not
treated for syphilis will develop tertiary syphilis.
 It causes serious damage to the body.
 Symptoms can begin years or even decades after
initial infection.
 ETIOLOGY
 caused by the spirochete bacterium Treponema pallidum.
 Bacteria can enter one’s body if he/she have close contact
with an infected sore, normally during vaginal, anal or
oral sex or by sharing sex toys.

51. PATHOPHYSIOLOGY
 It initiates infection when it gains access to
subcutaneous tissues via microscopic abrasions
that occur during sexual intercourse.
 It initiates ulcerative lesion, the chancre.
 It elicits innate and adaptive cellular immune
responses.
 Humoral immune responses are generated, leading
to the development of a variety of antibodies.

56. GONORRHOEA
 It is a STI caused by bacteria known as Neisseria gonorrhoeae
(gonococcus).
 It usually affects the genital area, although throat or anus may
also be affected.
 It affects both men and women and is easily transmitted
during vaginal intercourse.
 It is transmitted from any kind of sexual contact including –
 Vaginal intercourse
 Anal intercourse
 Oral intercourse

57. PATHOPHYSIOLOGY
 Gonococci are readily seen in smears (urethral, endcervical or
conjunctival exudates) and cultures, and appear as bean
shaped pairs.
 The organisms are cultured from tampons, urethral swabs,
urine, specimens from endocervix, vagina, anus and pharynx.
 It begins as a surface infection of the mucous membranes, that
is catarrh.
 The bacteria attach to and spread along the cells of the surface
mucous membranes, after which they invade superficially and
provoke acute inflammation.

58.  Gonococci attached to the columnar and transitional
epithelium of the urogenital tract.
 After an incubation period of 3 to 5 days, men usually
have purulent urethral discharge and dysuria.
 The first manifestation of infection in women is usually
endocervicitis, with vaginal discharge or bleeding.
 The infection may extends to the fallopian tubes, where
it produces acute and chronic salpingitis and pelvic
inflammatory disease.