Tuesday 7 June 2016

What is rubella? |


Causes and Symptoms


Rubella can be either acquired, infecting both children and adults, or congenital, infecting a fetus before birth. Acquired rubella is typically a mild disease with few complications. The incubation period is usually sixteen to eighteen days, but it can last fourteen to twenty-one days. For children, the first symptom is typically a rash that is small, red, and spotty. It starts on the face and behind the ears and spreads downward in the next one or two days. This rash is much milder than the rash of measles. In adults, the rash is preceded by symptoms that include a low-grade fever, headache, loss of appetite, mildly red eyes, a stuffy nose, a sore throat, coughing, and lymph node enlargement in the neck. Typically, this enlargement occurs behind the ears and in the back of the neck.



Complications of rubella are more common in adults, particularly in young women. The most common complications are arthralgia and arthritis. These joint manifestations can occur in any time from when the rash subsides to several weeks later. Rarer complications include effects on the blood, the heart, and the nervous system.


Congenital rubella is associated with multiple birth defects
in the infant. The most common manifestations of congenital rubella affect three areas: growth, the blood, and the central nervous system. The effects on growth include prematurity and intrauterine growth retardation. The effects on the blood include thrombocytopenia (a decrease in platelets), anemia, and an enlarged liver and spleen. The effects on the central nervous system include microcephaly (a small head), deafness, eye damage (including cataracts and retinal damage), mental retardation, and behavioral disorders. Whether these effects of congenital rubella are manifested depends on the timing of the infection during pregnancy and the severity of the infection. Some newborns may appear normal at delivery and develop manifestations during their first five years of life.


The diagnosis of acquired rubella primarily hangs on the clinical symptoms, such as a rash and lymph node enlargement in the back of the neck. The diagnosis of congenital rubella may be confused with other congenital or perinatal infections, such as syphilis, toxoplasmosis, herpes simplex, and Cytomegalovirus (CMV). These congenital infections can all lead to intrauterine growth retardation, deafness, mental retardation, and thrombocytopenia.




Treatment and Therapy

Infants with congenital rubella must be viewed as having a continually evolving disease, since there is no present method to stop or decrease the replication of the rubella virus in the infected newborn. No antiviral medications or antibody preparations have been found to be of therapeutic benefit in children with congenital rubella. Thus, therapy is supportive and requires a multidisciplinary approach. Hearing disabilities require testing, which involves special equipment for infants. If hearing loss is found, support for the child’s language and communication development must take place; specially designed educational programs are available. A full eye examination should be performed by an ophthalmologist.


Acquired rubella infection is fairly benign, and its management usually involves allowing the virus to run its course. Since the greatest damage done by rubella virus is to a developing fetus, the management of rubella should focus on prevention of infection in women of childbearing age. Because acquired rubella infection is commonly asymptomatic or subclinical, the only adequate way to prevent this disease and its effects on the fetus is immunization.


A vaccine
is available and has been shown to produce an excellent immune response. Two doses of rubella vaccine are recommended, given as the combined vaccine known as measles, mumps, and rubella (MMR). The first dose is given to a child at twelve to fifteen months of age. The second dose should be given prior to the child’s entry into school. The vaccine should also be given to adult women who have not received the vaccine previously.


Although it is not recommended that the vaccine be given to pregnant women because of the theoretical risk of inducing congenital rubella, no infants whose mothers were vaccinated during pregnancy have shown congenital defects. Rubella vaccine should not be given after the administration of antibody preparations. The vaccine also should not be given to immunosuppressed patients unless recommended by a doctor. The side effects of the vaccine, occurring in about 10 percent of children, include fever, a rash, and lymph node enlargement. Adult women are prone to developing arthralgia after receiving the rubella vaccine. Other, very rare complications of the vaccine have also occurred.




Perspective and Prospects

Since the introduction of the rubella vaccine in the United States in 1969, rubella and the associated congenital rubella syndrome have been virtually eliminated from the Western Hemisphere, signaling the success of the Unites States’ immunization program. Nearly 58,000 cases of rubella were reported in the United States in 1969; by 1999 that number had fallen to 272; no endemic case of rubella has been reported in the Americas since 2009. However, rubella continues to be a health problem in developing countries in other parts of the world, with the World Health Organization reporting an estimated 110,000 babies born each year with congenital rubella syndrome.




Bibliography


Beers, Mark H., et al., eds. The Merck Manual of Diagnosis and Therapy. 18th ed. Whitehouse Station, N.J.: Merck Research Laboratories, 2006.



Behrman, Richard E., Robert M. Kliegman, and Hal B. Jenson, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia: Saunders/Elsevier, 2011.



Bellenir, Karen, and Peter D. Dresser, eds. Contagious and Noncontagious Infectious Diseases Sourcebook. Detroit, Mich.: Omnigraphics, 1996.



Carson-DeWitt, Rosalyn. "Rubella." Health Library, September 27, 2012.



Martin, Richard J., Avroy A. Fanaroff, and Michele C. Walsh, eds. Fanaroff and Martin’s Neonatal-Perinatal Medicine: Diseases of the Fetus and Infant. 2 vols. 9th ed. Philadelphia: Mosby/Elsevier, 2011.



Middlemiss, Prisca. What’s That Rash? How to Identify and Treat Childhood Rashes. London: Hamlyn, 2002.



"Rubella." World Health Organization, July, 2012.



Shaw, Michael, ed. Everything You Need to Know About Diseases. Springhouse, Pa.: Springhouse Press, 1996.



Woolf, Alan D., et al., eds. The Children’s Hospital Guide to Your Child’s Health and Development. Cambridge, Mass.: Perseus, 2002.

No comments:

Post a Comment

How can a 0.5 molal solution be less concentrated than a 0.5 molar solution?

The answer lies in the units being used. "Molar" refers to molarity, a unit of measurement that describes how many moles of a solu...