Symptoms of roseola infantum

For young children, mothers need to take good care of them. Because young children have relatively weak disease resistance, it is very common for them to experience roseola infantum, which refers to high fever, rash, and extremely unstable emotions, anorexia, and crying. You can choose physical adjustment, such as wiping the skin with alcohol, or you can use medication. Let's take a look at what the symptoms of roseola infantum are.

2. HHV-6 has the typical morphological characteristics of the herpesvirus family. The virus particles are round, composed of 162 capsomeres forming an icosahedral symmetrical nucleocapsid with a diameter of 90 to 110 nm; the outside is composed of cortical particles forming a cortical layer, 20 to 40 nm thick; the outermost layer is covered with a lipid membrane, and there are irregular glycoprotein protrusions on the surface. The core is a linear double-stranded DNA wrapped around a core protein to form an axial filament; the mature and released virus particles have a diameter of 180 to 200 nm.

On the first 1-2 days after the onset of the disease, the white blood cell count may increase, but it will decrease significantly after the rash occurs, while the lymphocyte count will increase, reaching a maximum of over 90%.

2. Virus Isolation

Virus isolation is the diagnostic method for HHV-6 and 7 infections. HHV-6 and 7 can proliferate in fresh cord blood mononuclear cells or adult peripheral blood mononuclear cells. However, substances such as phytohemagglutinin (PHA), IL-2, and dexamethasone need to be added to the culture medium. The infected cells show pathological changes in about 7 days, and the cells are pleomorphic, with karyopyknosis and multinucleated cells. Infected cells can continue to survive for 7 days after developing pathological changes, while uninfected cells die within 7 days of culture. Since virus isolation and culture is time-consuming and not suitable for early diagnosis, it is generally only used in laboratory research.

Viral antigen testing is suitable for early diagnosis, but viremia lasts for a short time, making it difficult to collect specimens in a timely manner. Immunohistochemistry is currently widely used to detect viral antigens in cells and tissues. A positive antigen result can be used as a basis for diagnosis.