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Human Herpes virus type 6 (HHV-6）人類皰疹病毒6型
By:
Joe Hing Kwok Chu
HHV-6 was first discovered in 1986. It was discovered by studying the
patients with lymphatic cell hyperplasia and patients with HIV. The
virus possesses the shape of herpes viruses and like to attach to the
lymph cells. It was called HHV-6 because it was new at the time of
discovery, besides the
other 5 types of viruses
already had been discovered. This virus infects human white blood cells,
specifically T lymphocytes.
Usually children get this HHV-6 infection before 2 years old. Using
immunofluorescence technique, 60 to 80 % of the population show
the HHV-6 antigen in the serum. Most people infected with HHV-6 do not
show symptoms. Symptomatic infections typically induces
exanthema subitum (roseola infantum). More severe primary infections may
include hepatitis, inflammation of the brain and mengis, interstitial
pneumonia, and
mononucleosis like syndrome. In patients using immune system suppressing
drugs, such as
transplant recipients, HHV-6 primary infection or reactivation patients
may induce a rejection of transplanted organs and death.
Diagnosis: fever with lymphadenopathy (chronic
enlargement of lymph nodes), a mononucleosis-like disease with negative
test results for acute CMV and EBV infection. In children under 2
years of age usually show febrile seizures.
Treatments include
using phosphono formic acid (PFA) and phosphono acetic acid ( PAA).
人類皰疹病毒6型
人類皰疹病毒6型（Human Herpes virus type
6,HHV-6）是1986年從淋巴增殖異常患者及愛滋病病人外週血單細胞首先分離到一種具有皰疹病毒形態和嗜淋巴細胞的新病毒，它與已知的5個皰疹病毒
的抗原性和酶切圖譜不同，故名HHV-6。
人類感染HHV-6十分普遍，但多為隱性感染。免疫熒光試驗可在60～80%兒童及成人血清中查到HHV-6抗體。HHV-6是嬰兒急疹（玫瑰疹）的病原，並證實與淋巴增殖性疾病、自身免疫病和免疫缺陷病人感染等有關。隨著器官移植的發展和愛滋病病人的增多，HHV-6感染變得日益重要。
微生物學檢查，可採取早期病人外週血單核細胞與經活化（用PHA、IL2）的臍帶血淋巴細胞共培養，或用活化的T細胞系（為HSB2）感染病人體液（唾液、尿液、血液等）進行病毒分離。亦可用原性雜交和PCR技術檢測感染細胞或組織中病毒DNA。及血清學試驗（IFA，ELISA）檢測抗病毒lgM和lgG，以確定近期感染和流行病學調查。
常用治療藥物是磷乙酸和磷甲酸，兩者均可抑制病毒聚合酶viral
polymerase 的活性，阻斷DNA復制。
磷甲酸和磷乙酸是焦磷酸類似物，當 RNA和 DNA合成時它干擾聚合酶接觸到三磷酸核苷，PFA和 PAA的三鈉鹽抑制病毒聚合酶活力所需濃度遠在封閉宿主細胞的聚合酶活力所需濃度之下，因此它是一個很有用的抗病毒化合物。1979年Nordenfelt等在瑞典証明，PFA在試管內是一個有力的HBV－DNAP抑制劑。
1980年 Hess等在西德証明 PFA是 HBV DNAP的非競爭抑制劑，它似乎是與延長的DNA分子焦磷酸結合位點相互作用。有報道PFA可引起血清DNAP水平的抑制及肝細胞內HBcAg反應性降低。腸道外應用PFA治療慢性乙肝病人的報告尚不多見。
The
5 types of common herpes viruses before the discovery of HHV-6: [1]
- herpes simplex virus, type one: the eruption of fluid-containing
vesicles on the mouth, lips, or face.
-
herpes simplex virus, type two:
recurring viral disease marked by the eruption of
fluid-containing vesicles on the genitals.
- Cytomegalovirus: Any of a group of herpes viruses that attack and
enlarge epithelial cells. Such viruses also cause a disease of infants
characterized by circulatory dysfunction and microcephaly.
- Epstein-Barr virus: causes of infectious mononucleosis. It is also
associated with various types of human cancers.
- Varicella zoster virus (VSV): causes chickenpox and later
re-emerge as shingles.
Mononeuclosis:
symptoms are fever, severe sore throat, swollen glands, and fatigue.
Serious symptoms can include abdominal pain which may suggest inflamed
spleen and/or inflamed liver. Difficulty in breathing may suggest that
the glands in the throat can be swollen. Blood test will show large
number of single nucleus white cells.
[1] answers.com
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