1. Diphtheria is caused by Corynebacterium diphtheriae and affects the throat and respiratory system. 2. It is transmitted through respiratory droplets or direct contact and symptoms include sore throat and formation of a membrane in the throat. 3. Treatment involves antitoxin administration and antibiotics while prevention focuses on vaccination, isolation of cases and carriers, and hygiene education.

1. BY
Mrs. SAKTHYPRIYA.S, M. Sc(CHN)
Asst. Professor ,
SMVNC, Puducherry

3. Definition
 Diphtheria is an acute infectious disease caused by
toxigenic strains of Corynebacterium diphtheria

4. Epidemiological triad - Diptheria
 TIME
Agent
Cornynebacterium.
diphtheriae
Host Man
Environment
- all season- winter month
favors its spread

5. Epidemiological triad - Diptheria
Agent factor
Agent:
The causative agent, C. diphtheriae is a gram-positive,
non-motile organism.
It has no invasive power, but produces a powerful
exotoxin.
 Three types of diphtheria bacilli are differentiated -
gravis, mitis, and intermedius, all pathogenic to man.

6. Source of infection:
The source of infection is a case or carrier
Infective Material:
Nasopharyngeal secretions, discharges from skin lesions,
contaminated fomites and possibly infected dust
Period Of Infectivity:
vary from 14 to 28 days from the onset of the disease, but
carriers may remain infective for much longer periods.

7. Host factor
Age: Affects children aged 1 to 5 years.
Sex : Both sexes are affected
Immunity :
 Infants born of immune mothers are relatively
immune during the first few weeks or months of life.

8. Environment factor

Cases of diphtheria occur in all seasons, although
winter months favours its spread

9. Mode of Transmission
Droplet infection
Droplet nuclei
Infected cutaneous lesions.
Transmission by objects
(e.g., cups, thermometers, toys, pencils),
contaminated by the nasopharyngeal secretions of the
patient is possible, but for only short periods.
Incubation period
2 to 6 days.

10. Clinical features
1. Pharyngotonsillar diphtheria:
Sore throat, difficulty in swallowing, low grade fever.
Mild erythema, localized exudate, or a membrane.
 In the early stage a membrane may be whitish and may
wipe off easily. The membrane may extend to become
thick, blue-white to grey-black, and adherent.
 oedema of the submandibular area and the anterior
portion of the neck, along with lymphadenopathy,
giving a characteristic "bullnecked" appearance.

11. 2. Laryngotracheal diphtheria:
 Hoarseness and croupy cough and, if the
infection extends into bronchial tree, is the most
severe form of disease.
3. Nasal diphtheria:
 The mildest form usually is localized to the septum
or turbinate of one side of the nose occasionally may
extend into the pharynx.
4. Cutaneous diphtheria:
 An ulcer surrounded by erythema and covered
with a membrane.
 Conjunctiva and genitals may also be affected.

12. Diagnosis
SCHICK TEST
Schick test is an intradermal skin test.
In forearm intradermally 0.1 to 0.2 ml (1/50 MLD{millions of litre
per day})of Schick test toxin administered, while into the
opposite arm is injected as a "control" the same amount of toxin
which has been inactivated by heat..
The following reactions may be observed.
(a)NEGATIVE REACTION :
- no reaction on either arm.
- In quantitative terms, the test will be negative if the blood
serum contains more than 0.03 units of antitoxin per ml.

13. (b)POSITIVE REACTION:
- In the test arm, a circumscribed red flush if 10-50 mm diameter generally
appears within 24-36 hours reaching its maximum development by the 4th
to 7th day.
- This slowly fades into a brown patch and the skin desquamates.
- The control arm shows no change. The person is susceptible to
diphtheria
(c) PSEUDO-POSITIVE REACTION:
- A red flush develops equally on both the arms, but much less circumscribed
than the true positive reaction.
- The reaction fades very quickly and disappears by the 4th day.
- This is an allergic type of reaction.
- The test is interpreted as Schick-negative.

14. (d) COMBINED REACTION:
-The control arm shows a pseudo-positive reaction and the
test arm a true positive reaction.
- The person is susceptible to diphtheria.

15. Control -1. CASES AND CARRIERS
(a)Early detection
(b) Isolation:
- All cases, carriers should be promptly isolated, 14 days
or until proved free of infection.
- At least 2 consecutive nose and throat swabs, taken 24
hours apart, should be negative before terminating
isolation.

16. Treatment :
(i) CASES : diphtheria antitoxin given, IM or IV, in
doses ranging from 10,000 to 80,000 units or more,
depending upon the severity of the case, after a test
dose of 0.2 ml subcutaneously.
 penicillin (2.5 lakh units every 6 hours)
 erythromycin (250 mg every 6 hrs.) for 5 to 6 days to
clear the throat of C. diphtheriae
(ii)CARRIERS: The carriers should be treated with 10
day course of oral erythromycin,

17. 2. CONTACTS
 throat swabbed and their immunity status determined.
(a) where primary immunization or booster dose was received
within the previous 2 years, no further action would be needed
(b) where primary course or booster dose of diphtheria toxoid was
received more than 2 years before, only a booster dose of
diphtheria toxoid need be given
c) non-immunized close contact should receive prophylactic
penicillin or erythromycin.
 They should be given 1000-2000 units of diphtheria antitoxin
and actively immunized against diphtheria.
 Contacts should be' placed under medical surveillance and
examined daily for evidence of diphtheria for at least a week after
exposure.

18. 3. COMMUNITY
By active immunization with diphtheria toxoid of all
infants as per the Immunization scheduled.
Prevention
Diphtheria Immunization
a. Combined or mixed
vaccines
DPT (diphtheria-pertussis-
tetanus vaccine)
DT (diphtheria-tetanus toxoid)
dT (diphtheria-tetanus, adult
type)
b. Single vaccines
FT (formal-toxoid)
APT (alum-precipitated toxoid)
PTAP (purified toxoid
aluminium phosphate)
PTAH (purified toxoid
aluminium hydroxide)
TAF (toxoid-antitoxin floccule
c. Antisera
Diphtheria anti-toxin

19. Role of Community Health Nurse
 Instruct/advice the mother to Vaccinate the child as
per the Immunization scheduled on time .
 Consult the doctor if any diptheria possible symptoms
occur
 Keep the environment clean
 Maintain the proper hygienic practices
 Educate the family about the prevention and control
measures of diptheria condition