Rubella
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[edit] Rubella
This viral infection, also known as "German measles", is one of the six childhood rashes and is caused by an RNA virus, the rubella virus. Overall this is a very benign infection compared to measles. But it is feared mostly because it can lead to miscarriages (=spontaneous abortions), to death of a fetus and to congenital defects in the affected fetus. The risk for this is highest during an early pregnancy. This is why the vaccination program with MMR vaccines in girls has been emphasized. Otherwise there is a higher probability for a high risk pregnancy. In the US rubella is presently on an all time low after a general immunization program had been introduced in the early 1970's. The immunization effect lasts for about 15 years and a simple blood test can determine the antibody titer , which tells the physician whether or not the person would need re-immunization. About 10 to 15% of young adults are not protected against rubella (negative rubella titer). It is the females among them that should be vaccinated to avoid deafness, heart diesase and intrauterine death in their future pregnancies.
Signs and Symptoms:
The signs and symptoms of rubella are very fleeting with a 2 to 4 day prodromal stage where there is a mild fever, the patients feels unwell and there is mild lymph gland swelling (lymphadenopathy), particularly behind the ears and in the lower back part of the neck. Children may not even have these symptoms as much as adults who are more affected by this. In adults there may also be joint pains, headaches and a rhinitis (runny nose). In adults there can occasionally be a more severe form where the brain is affected by the rubella virus(viral encephalitis). The typical rubella rash occurs after an asymptomatic 2 to 3 week incubation period and at about day 4 or 5 of the prodromal stage with cold like symptoms. The rash is much more subtle than measles and starts (similar to measles) in the face, but travels fairly quickly along the neck into the trunk and the extremities. On the second day of the rash the fever, if this was present, will disappear. The rash also becomes more of a spotty appearance and there are also spots that appear on the palate. These are called Forschheimer's spots (petechial spots on the palate) and help the physician to delineate it from the other rashes (e.g. there are NO Koplik spots with rubella as it would be with measles). The rash disappears after 4 to 5 days at the most. In large military outbreaks there has been the occasional encephalitis, but in most cases this recovers spontaneously. Only in rare cases is this fatal.
Diagnosis:
The diagnosis is made clinically. It is based on the combination of the typical skin rash, the presence of the lymphadenopathy (swollen lymph glands behind the ears)and the absence of Koplik spots. Only in pregnant patients is it important to do a comparison between the acute and the recovery serum (more than 4-fold rise of specific anti-rubella titer between initial serum and the 4 to 8 week recovery serum). Cases with encephalitis weould also require this blood test.
Treatnment:
Treatment is only symptomatic. There are no antibiotics that are needed. The body produces antibodies in the days and weeks following the infection, which often provides a life long protection from rubella in the future. Occasionally a middle ear infection develops, which is due to a bacterial superinfection and antibiotics are effective for this.
Prevention:
As already indicated the medical landscape has changed tremendously for the better since the introduction of mass immunization in the early 1970's. Physicians no longer see the devastating effect of a relatively minor childhood rash on mothers and unborn children with the end result of deafness, blindness, learning problems, if the fetus even survives. Vaccination to prevent these disasters is given to children and all boys and girls postpuberty. Female college students should have a rubella titer checked to ensure that the effect of the childhood vaccine is not wearing off (it only lasts about 15 years). When a booster vaccination is given in a female, conception needs to be avoided for 28 days as this is a live vaccine with an attenuated vaccine virus and if a woman should get pregnant right after vaccination, the risk of damage to the fetus is about 3 to 4%. For the same reason vaccination during pregnancy is not permissible. There have been heated discussions in the literature and popular press regarding possible side effects of the vaccine. Joint aches and pains, a mild fever, also a mild skin rash can occur following vaccination for a period of 1 to 2 weeks. However, as the position paper from the WHO shows the benefits of the vaccine far outweigh the dangers of not administering it.
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References: 1. David Heymann, MD, editor: Control of Communicable Diseases Manual, American Public Health Association, 2004. 2. The Merck Manual,18th edition. Merck&Co., 2006.
