Rubella

The etiologic agent responsible for rubella disease is Rubella virus, a single-helix RNA virus. Under an electron microscope it appears spherical in shape, with a diameter of 40 to 80 nm. The genome represented by an RNA molecule with positive polarity and enclosed in an icosahedral capsid.
Two types of glycoproteins, E1 and E2, are arranged on the surface. The E1 glycoprotein acts as a viral antigen that enables virus recognition and is responsible for adhesion to the target cell. The E2 glycoprotein is responsible for ensuring the proper folding of E1.
Rubella virus belongs to the TORCH complex, an acronym for a set of pathogens that are particularly serious if they are contracted during pregnancy.

Rubella virus is transmitted airborne, particularly by droplets, the tiny respiratory droplets emitted by the sick person, by sneezing, coughing or even talking. The disease is also transmissible by direct contact with nasopharyngeal secretions. The contagious period of the disease is usually 7 days before to 7 days after the appearance of the exanthem, but the virus may be present up to 14 days after the exanthem. The disease can be transmitted vertically, from infected mother to the product of conception, and infants can spread the virus for several months and up to a year after birth.

Rubella disease is present throughout the world. Humans represent the only reservoir of the virus, which infects people through the air. With the introduction of vaccination, the incidence of the disease has declined significantly. The region of the Americas was one of the first areas in the world to eliminate rubella virus in 2009. In 2018, according to the latest data published by WHO, 42 of the 53 states in the European Reason achieved the goal of interrupting the chain of transmission of the virus, for at least 12 months. In other countries (including Italy) rubella still remains endemic. A total of 579 cases were reported, in 2018, our country takes the third place for number of cases after Poland and Germany. The incidence of rubella in Italy between 1971 to 1996 was quite high and in an epidemic pattern with peaks every 4-6 years, when 30,000 to 60,000 cases per year were reported. These figures began to decline from the late 1990s, when vaccination was introduced. Integrated health surveillance for measles and rubella was introduced in 2013. There have been 252 cases of rubella reported nationally from 2013 to 2019. with a peak in 2017 (68 cases). Laboratory-confirmed cases, on the other hand, are 50 percent.

After an incubation period ranging from 12 to 23 days (average is 18 days), the first symptoms occur, which are present in 50 percent of cases. The clinical course of the disease can be divided into two categories: acquired rubella and congenital rubella.

Acquired rubella
The term acquire means that the infection occurs in the postnatal period. It generally has a benign course in children and mildly challenging in adults.

In the initial, short-lived phase (about 24-36 hours), there is the appearance of fever, headache, joint pain, pharyngeal inflammatory process, and swelling of lymph nodes located on the sides of the ears and behind the nape of the neck.

Subsequently, slightly raised macules, called maculopapulosis, appear on the face and nape of the neck, which are pinkish or pale red in color, roundish, about 2-5 mm in size, and have no tendency to converge with each other, which is very important for differential diagnosis with measles. The rash evolves cranio-caudally and regresses within 2-3 days. A hot bath or shower accentuates this rash.

A petechial exanthem on the soft palate, called Forscheimer's patches, is seen, especially in children; it is a characteristic but not pathognomonic sign (i.e., not allowing diagnosis).

Rubella infection tends to heal, within a few days, resulting in permanent immunity. Postnatal rubella complications are less frequent than those of measles but not entirely negligible.

However, complications of rubella include acute arthritis and temporary arthralgias, which are especially common in adulthood. The action of the virus can compromise the immune system by causing thrombocytopenia (decreased platelet count) and encephalitis, which is somewhat less frequent but has fatal outcomes.

Congenital rubella
This is a condition that occurs as a result of infection during pregnancy in nonimmune women.

In the first weeks of gestation, infection can result in increased risk of miscarriage or multiple fetuses and cardiac malformations, such as peripheral pulmonary stenosis and ventricular septal defect. It can cause, in addition, eye defects, such as cataracts, glaucoma, and retinitis pigmentata, as well as neurological damage such as microcephaly.

Later, the expanded congenital rubella syndrome, characterized by chronic rash, hepatitis, interstitial pneumonia, and more, can occur. The consequences of rubella in the fetus are multiple and can also result in mental retardation and speech disorders.

Infants with congenital rubella can shed the virus for several months and up to a year. In 2018 (February 2018), our country recorded only one confirmed case of congenital rubella. A peak recorded in 2008 with 30 confirmed cases.

Diagnosis of rubella is based primarily on clinical symptoms, but it can be complicated, as it can be confused with mononucleosis or measles, especially if they are mild forms. Establishing the diagnosis relies on laboratory investigations, which mainly look for the presence of rubella-specific immunoglobulins, which are present during the early stage of the disease. One can isolate the virus by identifying its genome using the retrotranscriptional PCR technique.

The only treatment for rubella is symptomatic. Rest and a proper diet form the basis of treatment.
The doctor may prescribe medication in case of arthritis or antibiotics if bacterial complications are present.

The elimination of rubella has been a key goal of WHO and our country since 2015, with the National Plan for the Elimination of Measles and Congenital Rubella. Vaccination is the only effective method to counter the spread of this virus. It is a combined vaccine with measles and mumps or even varicella. According to the vaccine calendar, immunization against measles, mumps, rubella and varicella (MPRV), starts with the completion of the 12th month of life and by the 15th month for the first dose. A further booster is scheduled around 5-6 years of age. For unvaccinated and nonimmune individuals, they can still get the vaccine with a gap of 4 weeks between the two doses. Vaccination is contraindicated for some people because it is a live attenuated vaccine, such as pregnant women and the immunocompromised. For this reason, it is essential that women who are not immune against rubella get vaccinated, at least one month before conception to prevent congenital rubella.