Both HHV-6B and HHV-7, as well as other viruses, can cause a skin condition in infants known as exanthema subitum, although HHV-7 causes the disease less frequently than HHV-6B. HHV-7 infection also leads to or is associated with a number of other symptoms, including acute febrile respiratory disease, fever, rash, vomiting, diarrhea, low lymphocyte counts, 5 and febrile seizures, 6 though most often no symptoms present at all. Neuroinvasion by human herpesvirus type 7 in a case of exanthem subitum with severe neurologic manifestations. There are eight currently identified members of the human herpes virus family. Latency can be maintained in the white cells of the blood, kidneys, secretory glands and other tissues. EBV has also been associated with other diseases, including:. Human herpesvirus 6 (HHV-6) was the sixth herpesvirus discovered. HHV-6B causes the childhood illness roseola infantum, whereas HHV-6A has been isolated mainly in immunocompromised hosts. Acute HHV-6 infection is rare in immunocompetent adults but may manifest as a mononucleosislike illness characterized by fever, lymphadenopathy, and hepatitis or encephalitis, with negative test results for CMV or Epstein-Barr virus (EBV).
Roseola is a disease caused by human herpes virus type 6B (HHV-6B) and possibly type 7 (HHV-7). These herpes viruses have only been identified in recent years and we are still learning about the full range of diseases caused by them. Both HHV-6B and HHV-7, as well as other viruses, can cause a rash roseola infantum in infants, but HHV-6B more than HHV-7. Even though there are usually no symptoms present with HHV-7, the infection is also associated with symptoms including acute febrile respiratory disease, fever, rash, vomiting, diarrhea, low lymphocyte counts, and febrile seizures. However, HHV-6 can also cause fever without rash or rash without fever. Human herpes virus 7 may be responsible for second or recurrent cases of roseola that were originally caused by HHV-6.
HHV1 can also lead to infection in the genital area causing genital herpes usually through oral-genital contact, such as during oral sex. Human herpes virus 7 (HHV7) is even more recently observed and is closely related to HHV6. Although both human herpesvirus (HHV) 6 and HHV-7 infections are ubiquitous during childhood, few acute HHV-7 infections are identified. These findings, previously unrecognized in otherwise healthy children, suggest that HHV-7 viremia could represent primary or reactivated infection and may be affected by the interaction between HHV-6 and HHV-7. Both HHV-7 and HHV-6 appear to cause ubiquitous infections in early childhood, yet primary HHV-7 infections are rarely recognized. The role and frequency of human herpesviruses (HHV)-6 and -7 in central nervous system (CNS) diseases of children are unclear. HHV-6 may occasionally cause meningitis in young infants. Pohl-Koppe A, Blay M, Jager G, Weiss M. Human herpes virus type 7 DNA in the cerebrospinal fluid of children with central nervous system diseases.
Roseola (human Herpes Virus Type 6, HHV-6). Dermnet Nz
In addition, HHV-6 (but not HHV-7) carries a homolog of the adenoassociated type 2 parvovirus rep gene (24), which is transcribed in latently infected cells (25). Occasionally, HHV-7 may also cause fever with or without rash. Herpes simplex virus type 1 (HSV-1, herpes labialis): Everyone is at risk for HSV-1 (herpes labialis or oral herpes). The virus can also be spread to the genital area of another individual by having oral sex. It should be noted that HSV-1 is becoming a major cause of genital herpes as well, and in some studies, it is now a more important cause of genital herpes than HHV-2. This period lasts about 5-7 days. Also known as exanthem subitum (eg-ZAN-thum SU-bih-tum), roseola infantum is an acute viral infection that mainly affects children between the ages of 6 months and 3 years and is characterized by high fever followed by a rash. (her-peez-VY-rus) type 6 (HHV 6) or human herpesvirus type 7 (HHV 7). HHV 6 and HHV 7 affect almost all children who are between 6 months and 3 years of age, but not all of these infections produce the illness recognized as roseola infantum. 1 and 2 (HSV-1 and HSV-2, respectively), human herpesvirus type 3 (HHV-3, or the varicella-zoster virus), human herpesvirus type 4 (HHV-4, including Epstein-Barr virus and lymphocryptovirus), human herpesvirus type 5 (HHV-5, or cytomegalovirus), human herpesvirus type 6 (HHV-6, including. Herpes simplex virus type 1 (HSV-1) is also known as a cold sore or fever blister. The lesions of herpes labialis usually last for 7-10 days, then begin to resolve. Moreover, HSV-1 can cause genital herpes, resulting in similar symptoms as infections caused by HSV-2. It can also be called Varicella-Zoster or Human Herpes Virus-3. With the exception of HHV-8, which causes Kaposi’s sarcoma in patients with AIDS, reactivation of HHVs can produce one or more of the following complications: meningitis, encephalitis, myelitis, vasculopathy, ganglioneuritis, retinal necrosis and optic neuritis. Although HSV neuropathy is now well documented, the exact type of HSV responsible for each form of neuropathy is still unknown. After herpes zoster, VZV can also spread to blood vessels of the brain, producing a unifocal or multifocal vasculopathy, particularly in immunocompromised individuals.
Herpes Virus: 8 Types
It also can cause symptoms such as fever and muscle aches. Human herpes virus type 6 (HHV-6) and 7 (HHV-7) are suspected of triggering autoimmune disorders, including multiple sclerosis, and roseola, a common illness of early childhood. Human herpes virus 6 (HHV6) and human herpes virus 7 (HHV7): Roseola is usually caused by HHV6, but it can also be caused by HHV7. In the past 2 years, a new virus HHV-7 was discovered which was similar to HHV-6. The predominant susceptible cell type is immature T cells which express OKT4. There are reports that the virus can cause encephalitic symptoms, possibly due to prolonged seizure. It is now also associated with a glandular fever like illness. Herpes viruses are a leading cause of human viral disease, second only to influenza and cold viruses. Both types of HSV can also persistently infect macrophages and lymphocytes.