Varicella Zoster Virus (VZV/HHV-3) is an acute infection that leads to varicella, or “chicken pox.” It’s contagious through direct contact with a skin lesion or through airborne spread from respiratory droplets. Over 90% of today’s adults acquired the virus during childhood and lifelong immunity is boosted every time there is contact with an active case of wild chickenpox, but as fewer children are getting the acute illness, more adults are getting shingles which is a more serious form of the VZ virus.
Epstein-Barr virus (EBV/HHV-4) is also surprisingly common and widespread amongst human populations. It infects human B-lymphocytes and epithelial cells. HHV-4 typically spreads through bodily fluids, particularly saliva through kissing, sharing utensils, toothbrushes, etc., but it can also be spread through blood and semen during sexual contact, blood transfusions, and organ transplants. Most people contract EBV at some point in their lives, often during childhood. EBV is responsible for infectious mononucleosis as well as other illnesses.
Cytomegalovirus (CMV/HHV-5) is another member of the herpes family. 50%-70% of all adults are infected as well as 50% of all children. The most common manifestation is gastrointestinal upsets. Typically, most infected people will go through life never knowing they were ever infected.
Human Herpesvirus type 6 (HBLV/HHV-6) is most commonly associated with Roseola infantum or ‘sixth disease’. Onset is abrupt with a high fever lasting 3-5 days and is followed by a rash on the torso and spreading to the limbs and face as temperature subsides.
Human Herpesvirus type 7 (HHV-7) infects nearly all children by the age of 3 and is transmitted mainly through saliva. It is very similar to HHV-6 and has been found to be the cause of some cases of roseola. There is no childhood disease or definable syndrome that is associated with an acute HHV-7 infection. It is believed, however, that HHV-7 can contribute to the development of other conditions, or can reactive HHV-4, the Epstein – Barr virus (EBV).
Human Herpesvirus type 8 (KSHV/HHV-8) also known as Kaposi’s sarcoma, manifests as a connective tissue cancer. HHV-8 produces a malignant lesion characterized by neoplastic cells and abnormally growing blood vessels. KSHV/HHV-8 is highest in central Africa and has been found in the saliva of many AIDS patients. The infection rate is low in the USA and Western Europe with intermediate rates in Mediterranean countries.
Complications from HHV 1, 2, 3, 4, 5, 6, 7, 8, are predominately seen if the immune system is compromised as a result of drug treatment, or suppression. Recent studies have revealed that contracting HHV in the form of chickenpox is in fact very beneficial to the developing immune system.