Rubella virus

The sample for the TORCH profile

1. Venous blood is collected to prepare the serum.
2. The other sample used is urine and spinal fluid for evidence of the infections for TORCH.
3. Diagnosis can be confirmed by the culture of one of the specific pathogens or by increased levels of IgM against the specific pathogen.

Purpose of the test (Indications) for Rubella virus

1. TORCH profile is done to find the cause of premature birth or abortion.
2. TORCH profile is used to screen infants for infections such as toxoplasmosis, cytomegalovirus, herpes simplex, rubella, and syphilis.

Definition of TORCH profile

1. TORCH profile includes the following tests:
   1. Toxoplasmosis antibody.
   2. Rubella antibody.
   3. Herpes Simplex.
   4. Cytomegalovirus
   5. Some people include syphilis as well.
2. These infections may lead to birth defects, growth delay, and brain and nervous system problems in the baby.
3. If TORCH screening on infants is positive, more testing will be needed to confirm the diagnosis. The mother will also need to be checked.
4. The test is ordered when a pregnant woman is suspected of having any of the TORCH infections.
5. These infections can be serious during pregnancy because they can cross the placenta from the mother to the developing fetus and cause congenital defects in the newborn.

Complications of TORCH infection:

1. The TORCH infections cause a syndrome characterized by:
   1. Microcephaly.
   2. Sensorineural deafness.
   3. Chorioretinitis.
   4. Hepatosplenomegaly.
   5. Thrombocytopenia.

TORCH infection signs/symptoms are:

1. Fever and poor feeding.
2. The newborn is often small for gestational age.
3. A petechial rash on the skin may be present, with small reddish or purplish spots due to bleeding from capillaries under the skin.
4. An enlarged liver and spleen (hepatosplenomegaly) are common, such as jaundice.
5. Hearing impairment, eye problems, mental retardation, autism, and death can be caused by TORCH infections.
6. The mother often has a mild infection with few or no symptoms.
7. The examiner may test blood, urine, and spinal fluid for evidence of the infections for TORCH.
8. Diagnosis can be confirmed by the culture of one of the specific pathogens or by increased levels of IgM against the pathogen.

Rubella  Virus

Sample of Rubella virus

• The virus may be isolated from CSF, urine, amniotic fluid, and other sites.

Definition of Rubella virus

1. This is a single-stranded RNA virus.
2. It is quite a common infection in childhood.
3. It is important due to its infection in the first trimester of pregnancy and fetus abnormalities.

Rubella virus structure

1. It is a single-stranded RNA virus.

Rubella virus interpretations:

1. Rubella is not a serious disease and is also called German measles.
2. This is also called 3-days measles.
3. The incubation period is around 14 days.
   1. These patients are contagious for about two weeks, ranging from 12 to 21 days.
4. There are fever and transient rashes in children and adults.
5. The illness may be subclinical in about 25% of the cases. This stage is also infective.
6. Infection during the first 16 weeks of pregnancy presents major risks for the unborn baby.
   1. When a pregnant woman has a rash and other symptoms of rubella, laboratory tests are required to make the diagnosis.
   2. This is effective in the first trimester of pregnancy.

Signs and Symptoms of Rubella virus infection:

1. There is exposure to the patient with Rubella 14 to 21 days before the onset.
2. There are lymphadenopathy and postauricular and cervical lymph nodes before the rash appears.
3. Post-natal Rubella:
4. It is usually asymptomatic in 50% of the cases.
5. The post-natal infection has a fever and malaise.
6. There is suboccipital adenitis.
7. Polyarthritis is seen in 25% of the cases. It usually subsides in one week but may persist for weeks. Rarely chronic arthritis develops.
8. A fine, pink maculopapular rash appears on the face, trunk, and extremities. It fades quickly and may be lost in one day in each area.

Complications of Rubella virus infection:

1. Affected infants show various pathologies like cataracts, microcephaly,  deafness, and heart defects.
2. There is a chance of spontaneous abortion and stillbirth.

Congenital Rubella virus infection (Rubella syndrome):

Signs and symptoms:

1. The infant may be asymptomatic at birth.
2. Later on, these babies may have cataracts and glaucoma.
3. There may have microphthalmia.
4. There is a hearing defect.
5. There is psychomotor retardation.
6.  There may be heart anomalies like patent ductus arteriosus.
7. The patient may have organomegaly.
8. There are maculopapular rashes.
9. The earlier newborn gets an infection, the more severe will be signs and symptoms.
10. Deafness is seen when a fetus gets an infection in the second trimester.
11. There may be cerebral damage.
12. There may be abortion or stillbirth.

Diagnosis of congenital infection:

1. Infants with congenital rubella infection can produce both IgM and IgG antibodies before birth.
2. These antibodies appear in the second trimester of fetal life.
3. In addition, fetuses get passive maternal IgG antibodies.
4. When infants get to the age of 6 to 8 months, maternal antibodies disappear. The presence of antibodies IgM or IgG indicates congenital or neonatal infection.
5. The presence of IgM antibodies is diagnostic of intrauterine life infection.

Diagnosis of Rubella virus infection:

1. This virus can be cultured from the nasopharynx; the best place is the posterior end of the nose.
2. After the onset of the rash, no need for culture. Now, serological tests are enough.
3. Commercial antigen kits are not available.
4. Antibodies kits are available as:
   1. Hemagglutination inhibition.
   2. Indirect hemagglutination.
   3. ELISA. This test is more reliable.
   4. Most IgG kits are available. Few companies are making for IgM.
   5. Few kits detect both IgG and IgM.
5. IgM antibody is diagnostic in the newborn.
   1. Congenital rubella in the first trimester is associated with congenital fetal abnormalities, like heart defects, brain damage, and deafness.
   2. Evidence of active infection in the mother.

6. If a woman’s titer is greater than 1:10 to 1:20, she is not susceptible to rubella infection.
7. If the titer is <1:8, it indicates she has no immunity to the rubella virus.
8. A fourfold rise in the titer in a period of 2 weeks indicates acute infection.
9. A negative rubella antibodies test indicates susceptibility to rubella infection.

Various antibodies in Rubella virus infection:

Summary of the Rubella virus infection:

1. Single IgG antibodies that test positive indicate immune status.
2. Advise IgM antibody for acute infection.
   1. If negative, repeat after 2 weeks.
3. For the diagnosis of congenital rubella virus infection, advise Igm antibodies on the fetus and mother.
4. For reinfection, advise IgG antibodies.
5. If a person develops a rash and there is doubt about rubella infection, then get one immediate blood sample for the test. Get another sample after two weeks of the rash.
6. Or advise IgM antibodies test for rubella after one week of the rash.

Vaccination of rubella virus infection:

1. Vaccination produces an immune response by producing antibodies (IgM + IgG) in around 95% of the cases.
2. Antibodies appear after 10 to 28 days of the vaccination.
3. Few people may take up to 8 weeks to show adequate antibodies.
4. In the case of non-responders, revaccination can produce an immune response.
5. IgG antibodies decline over time and may not be detectable after ten years of time.

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