Mumps viruses belong to the Paramyxoviridae family. They are enveloped, single-stranded negative-stranded RNA viruses. Currently only one human-pathogenic serotype of the virus is known. However, the World Health Organization (WHO) has divided the mumps virus into genotypes from A to N, which differ in their biological characteristics.
The differences between the genotypes can be, for example, neurovirulence or the ability to cross-react. The different genotypes are also often found geologically in other regions. Genotypes A, C, D, G and H are mainly found in North and South America. However, an increasing number of mumps diseases are caused by genotype G in Germany. Genotypes B, F, I, J/K and L are frequently found in the Asian and Pacific regions. A mumps disease (parotitis epidemica) can occur at any age, but it leads to lifelong immunity after initial infection.
Mumps viruses are mainly transmitted via the air by droplet infection. Although the transmission rarely occurs through contact with saliva-contaminated objects, it also happens through direct saliva contact.
A mumps disease usually shows itself in an inflammatory and painful swelling of the parotid gland (parotitis). This is one-sided in 20 to 30 percent of cases, i.e. only in one ear, and double-sided in the other cases. Prior to this, patients suffer from early symptoms such as fever, headache, discomfort, muscle pain and loss of appetite. In rare cases, a disease of the parotid gland can cause temporary (in 4 percent of cases) or permanent unilateral (persistent unilateral) deafness. However, this is only permanent in 1 out of 20,000 cases.
In the case of inpatients with an infection, it is recommended that they be accommodated in an isolation room using the following hygiene measures: hand disinfection, surface disinfection, disposable gloves, disposable gowns and mouth and nose protection.
According to Germany’s Infection Protection Act (§ 34 IfSG), for example, persons suffering from mumps or suspected of suffering from them are not allowed to carry out any teaching, educational, nursing, supervisory or other activities in communal facilities where they have contact with those cared for there. These people may only resume their employment after a doctor has ruled that they are no longer likely to spread the disease. Similarly, persons cared for in communal facilities with mumps infections may not enter the rooms serving the operation of the facility, use the facilities of the communal facility or participate in events of the communal facility. In Germany, mumps must be registered with doctors and laboratories throughout the country.
The required spectrum of action against mumps viruses is: limited virucidal