2. HISTORY - RUBELLA
Discovered in 18th century -
thought to be variant of measles
The Teratogenic property of the
infection was documented by an
Australian ophthalmologist
Norman McAlister Gregg, in 1941
The virus was isolated in 1962
2 04/04/2015
3. Introduction
From Latin meaning "little red"
An attenuated vaccine was
developed in 1967
First described as distinct
clinical entity in German
literature
3 04/04/2015
4. EPIDEMIOLOGY
17 04/04/2015
Occurs worldwide
The virus tends to peak in countries with temperate climates
Common in children ages 5-10 years old
Human are only known reservoir.
Host -3-10 yrs
Source of infection – Respiratory secretion
Infants with CRS may shed virus for a year or more
Immunity –life long
Occurs round the year, peak in late winter and spring season
Transmission – droplet, vertical transmission
I.P – 2-3 weeks average 18 days
Rubella is world wide in distribution
Epidemics occur every 4-9 years.
5. Rubella Virus
Togavirus
RNA virus
One antigenic type
Rapidly inactivated by chemical agents, low pH,
heat and ultraviolet light
4 04/04/2015
6. AGENT FACTORS
A- Agent
Causative agent: Rubella virus
ssRNA Virus of the
Togaviridae Family
genus Rubivirus
One antigenic type
Diameter 50 – 70 nm
Enveloped Spherical
Virus carry hemagglutinin
Virus multiply in the cytoplasm of infected cell.
Highly sensitive to heat, extremes of pH & uv light.
At 4°C, virus is relatively stable for 24 hours.6 04/04/2015
7. AGENT FACTORS cont.
7 04/04/2015
B- Source of infection
CASES
Subclinical
Clinical
Congenital from infected
pregnant women to fetus.
There is no known carrier
state.
C- Period of
communicability
It probably extends from
a week before symptoms
to about a week after
rash appears.
Infectivity is greatest
when the rash is
erupting.
8. HOST FACTORS
A- Age
Disease of childhood
3-10 yrs age group.
Following widespread
immunization
campaigns persons
older than 15 yrs
account for 70% cases
in developed
countries.
B- Immunity
One attack results in
life long immunity.
Infants of immune
mothers are protected
for 4-6 months.
In India, about 40% of
child bearing age
group women are
susceptible to rubella.
8 04/04/2015
9. Immunity - Rubella
Antibodies appear in
serum as rash fades and
antibody titres raise
Rapid raise in 1 – 3 weeks
Rash in association with
detection of IgM indicates
recent infection.
IgG antibodies persist for
life
9 04/04/2015
11. Mode of Transmission
Person to person- via
respiratory route:-
Droplet from nose & throat
Droplet nuclei (aerosols)
Maintain in human
population by chain
transmission.
Acquired during pregnancy- vertical
transmission:-
Virus can enter via the Placenta & infect the
foetus in utero (Congenital Rubella Syndrome).
11 04/04/2015
13. Pathogenesis Continued……
Respiratory
Tract Skin
Lymph
Nodes Joints
Placenta or
Fetus
• Cough
• Minor
sore
throat
• Rashes
• Lesions
• Mild
arthralgia
• arthritis
• Placentitis
• Fetal
Damage
• Lymphadenopathy
14 04/04/2015
Rubella Virus Developed in the nasopharynx
14. Rubella Clinical Features
Incubation period 14 days (range 12-23 days)
Low grade fever
Lymphadenopathy in
second week
Maculopapular rash 14-
17 days after exposure
18 04/04/2015
15. SIGNS AND SYMPTOMS
RASH-
After an incubation period of 14-21
days, the primary symptom of
rubella virus infection is
the appearance of a rash (exanthema)
on the face
which spreads to the trunk and limbs
and
usually fades after three days with no
staining or peeling of the skin.
The skin manifestations are called
"BLUEBERRY MUFFIN
LESIONS."19 04/04/2015
16. SIGNS AND SYMPTOMS
continued….
LYMPH NODE-
Tender lymphadenopathy
(particularly posterior
auricular and suboccipital
lymph nodes)
persist for up to a week.
20 04/04/2015
17. SIGNS AND SYMPTOMS
TEMPERATURE-Fever rarely rises above 38o C (100.4 o F)
21 04/04/2015
18. Other manifestations &
complications
May produce transient
Arthritis, particular in
women.
Serious complications
are-
Thrombocytopenia
Purpura
Encephalitis
22 04/04/2015
19. Congenital Rubella Syndrome
(crs)
Occurs during the first trimester of
pregnancy.
Affects the development of the fetus.
may lead to several birth defects.
Infection may affect all organs.
May lead to fetal death or premature
delivery.
Severity of damage to fetus depends
gestational age.
Infants: virus is isolated from urine
and feces.
27 04/04/2015
20. Rubella infection – At various
trimesters
28 04/04/2015
Ist trimester infections lead to abnormalities in 85 % of
cases and greater damage to organs
2nd trimester infections lead to defects in 16 %
> 20 weeks of pregnancy fetal defects are uncommon
However Rubella infection can also lead to fetal deaths,
and spontaneous abortion.
The intrauterine infections lead to viral excretion in
various secretion in newborn up to 12-18 months.
21. Rubella infection & Chance of
CRS
29 04/04/2015
0–28 days before conception - 43% chance
0–12 weeks after conception - 51% chance
13–26 weeks after conception - 23% chance
Infants are not generally affected if rubella is
contracted during the third trimester
22. Post natal Rubella
Occurs in Neonates and Childhood
Adult infection occurs through mucosa of the
upper respiratory tract spread to cervical
lymph nodes
Viremia develops after 7 – 9 day
Lasts for 13 – 15 days
Leads to development of antibodies
The appearance of antibodies coincides the
appearance of suggestive immunologic basis
for the rash
In 20 – 50 % cases of primary infections are
subclinical. 04/04/201530
23. Clinical Features
Rash at birth
Deafness
Cataracts
Heart defects
Microcephaly
Mental retardation
Bone alterations
Liver and spleen damage
32 04/04/2015
24. Diagnosis of Rubella in
Adults
36 04/04/2015
Clinical Diagnosis is unreliable
Many viral infections mimic Rubella
Specific diagnosis of infection with-
1 Isolation of virus
2 Evidence of seroconversion
25. Isolation and Identification of
virus
Nasopharyngeal or
throat swabs taken 6
days prior or after
appearance of rash is a
good source of Rubella
virus
Using cell cultured in
shell vial antigens can
be detected by
Immunofluresecent
methods37 04/04/2015
26. Medical Treatment
43 04/04/2015
Rubella is a mild self limited illness.
No specific treatment or Antiviral treatment is indicated.
Isolation and quarantine
Increase fluid intake
Encourage the patient to rest
Good ventilation
Encourage the patient to drink either lemon or orange juice
Provide health teaching about Rubella (cause, immunizations)
27. Treatment for acute maternal
rubella infection
44 04/04/2015
Acetaminophen for symptomatic relief
IgG –
role is controversial, CDC recommends limiting use of
immunoglobulin to women with known rubella exposure who
decline pregnancy termination.
Glucocorticoids, platelet transfusion, and other supportive
measures for complications.
Counseled about maternal-fetal transmission and offered
pregnancy termination, especially prior to 16 weeks
gestation.
After 20 weeks gestation- individualized management.
28. Prevention
Rubella vaccine is given to
children at 15 months of age
as a part of the MMR
(measles-mumps-rubella)
immunization.
The vaccine is live and
attenuated and confers
lifelong immunity.
Given to children 12 and 15
months and again between 3-
6 years of age
45 04/04/2015
29. Vaccination of Women of
Childbearing Age
Ask if pregnant or likely to
become so in next 4 weeks
Exclude those who say "yes
the vaccine has been already
taken"
For others
Explain theoretical risks
Vaccinate
47 04/04/2015
30. MMR Vaccine
The MMR vaccine is a mixture of three live
attenuated viruses, administered via injection
for immunization against measles, mumps
and rubella virus strain RA 27/3 .
It is generally administered to children around
the age of one year, with a second dose before
starting school (i.e. age 4/5).
48 04/04/2015
31. MMR Vaccine
The second dose is not a booster; it is a
dose to produce immunity in the small
number of persons (2-5%) who fail to
develop measles immunity after the first
dose, the vaccine was licensed in 1963
and the second dose was introduced in
the mid 1990s. It is widely used.
Contraindications= immunodeficiency
disorder, history of anaphylaxis to
neomycin, and pregnancy.
Side effects: arthritis, arthralgia, rash,
adinopathy, or fever.
49 04/04/2015
