EPIDEMIOLOGY OF RUBELLA

1. EPIDEMIOLOGY OF
RUBELLA (GERMAN
MEASLES)
DR. MAHESWARI JAIKUMAR.
maheswarijaikumar2103@gmail.com

4. RUBELLA VIRUS

5. RUBELLA VIRUS

6. RUBELLA/GERMAN MEASLES
• German measles is an acute
childhood infection, usually mild,
of short duration (3 days).

7. • Rubella is accompanied by low
grade fever, lymphadenopathy
and a maculopapular rash.
• Infection in early pregnancy may
result in serious congenital
defects including death of the
fetus.

10. AGENT
• Rubella is caused by an RNA
virus of the TOGAVIRUS family.
The virus can be propagated in
cell culture.

12. SOURCE OF INFECTION
• Clinical or subclinical case of
cases of rubella. ( A large
number of rubella infections are
subclinical. This is one of the
major differences between
measles and rubella)

13. PERIOD OF
COMMUNICABILITY
• Rubella is much less communicable
than measles (due to absence of
coughing).

14. • The period of communicability
probably extends from a week
before symptoms to about a
week after rash appears.
Infectivity is greatest when the
rash is erupting.

16. AGE
• Mainly a disease of childhood.
• Usually affects children between
3 & 10 Years.

17. IMMUNITY
• One attack results in lifelong
immunity.
• Secondary attacks are rare.

19. • Disease usually occurs in a
seasonal pattern.
• In temperate zones during the
late winter and spring, with
epidemics every 4-9 years.

20. TRANSMISSION
• The virus is transmitted directly
from person to person by
droplets from nose and throat
and droplet nuclei (aerosols)
from one week before the onset
of rashes to one week after it
has faded.

21. • The portal of entry is through
respiratory tract.
• The virus can cross placenta
(vertical transmission).

22. INCUBATION PERIOD
2 To 3 weeks; average 18 days.

23. CLINICAL FEATURES
• A large percentage of infections
are asymptomatic.
• However in a typical case, the
clinical features compromise the
following.

24. PRODROMAL
• The prodromal symptoms are
coryza, sore throat, low-grade
fever mark the of viraemia.

25. LYMPHADENOPATHY
• In susceptible individuals, the
enlargement of the post
auricular and posterior cervical
lymph node appears as early as 7
days before the appearance of
the rash.

26. • The enlarged glands may be found
10-14 days after the rash.

27. RASH
• The rash is often the first indication
of the disease in children.
• It appears first on the face, usually
within 24 hours of the onset of
prodromal symptoms.

28. • It is a minute, discrete, pinkish,
macular rash and not confluent
as the rash of measles.
• Conjunctivitis may occur.

29. • The rash spreads rapidly to the
trunk and extremities, by which
time it is often no longer
apparent on the face.
• The rash spreads much faster
and clears more rapidly than the
rash of measles.

30. • It disappears altogether by the
third day.
• The rash is an inconstant feature
of the disease.
• It is absent in subclinical cases.

31. COMPLICATIONS
• In rare instances arthralgia may
occur in several joints in adults.
• Thrombocytopenic purpura has
also been observed as a
complication.

32. DIAGNOSIS
• Due to its mildness and variability of
symptoms, the disease can go
unrecognized unless it is an epidemic.
• A definitive diagnosis of rubella is
possible only through virus isolation
and serology.

33. • Throat swabs should be cultured
for virus isolation; it takes longer
than serological diagnosis.
• The most widely used serological
test is the heamagglutination
inhibition test (HAI).

35. • Two blood samples are taken ,
the first sample within 5 days
after the onset of illness, and the
second 2 weeks later.
• More sensitive serological test
include the ELISA test and
radioimmunoassay.

36. CONGENITAL RUBELLA
• Congenital Rubella Syndrome
(CRS) refers to infants born with
defects secondary to intrauterine
infection or who manifest
symptoms or signs of
intrauterine infection sometime
after birth.

38. • Rubella infection inhibits cell
division and this is probably the
reason for congenital
malformations and low birth
weight.

39. • The classical triad of congenital
defects are deafness, cardiac
malformations and cataracts.
• Other resulting defects include
glaucoma, retinopathy,
microcephalus cerebral palsy,
IUGR,hepato-splenomegaly, and
mental and motor retardation.

40. • These defects occurring singly or
in combination have become
known as “Congenital rubella
Syndrome”.

42. • The first trimester of pregnancy
is crucial and disastrous for the
foetus as the organogenesis
takes place. Maternal infection
during this time is directly
associated with congenital
abnormalities.

43. PREVENTION
• Active immunization is available.
• RUBELLA VACCINE : RA 27/3
vaccine, produced in human
diploid fibro-blast is
recommended for prevention.

44. • RA 27/3 vaccine is administered
in a single dose of 0.5ml
subcutaneously.
• It may provoke some mild
reactions in some subjects such
as malaise, fever, mild rash and
transient arthralgia, but no
serious disability.

45. • Rubella vaccine is also available
as combined Measles, Mumps
and Rubella (MMR).
• It is equally effective.

48. VACCINATION STRATEGY
• MMR vaccination is given to
infants on completing 9 months
of age. (in the national
immunization schedule in India)

49. • In general the priority being to
protect women of child bearing age
(15-34 or 39 years of age) and then
to interrupt transmission of rubella
by vaccinating all children in the
community aged 1-14 years and
subsequently all children at one
year of age.

50. THANK YOU