Children with primary HHV-7 infection (n = 8) were identified and compared with children with primary HHV-6 infection (n = 29) detected during the same time period. HHV-7 was detected with similar frequency in salivas from donors with common cold or RAU. HHV-6 DNA, variant type, and viral loads were determined on samples (cord blood, peripheral blood, saliva, urine, hair) from 6 infants with TP-HHV-6 and on their parents’ hair. Since HHV-6 and HHV-7 persist in the host following primary infection, PCR methods which can identify clinically relevant viral replication are required. Maternal antibody may confound interpretation of serology in patients under 3 months of age. A total of 20 samples were positive for HHV-6 by culture and DNA PCR, of which 19 were positive by RT-PCR (sensitivity, 95%). Of these, 23 (13.2%) met the study criteria.

Although HHV-7 DNA was detected in the genital tract of two (2.7%) and seven (9.6%) pregnant women of a total of 73 during the first and third trimesters respectively, there was no statistical difference in the detection rate of the viral DNA between the trimesters. All NIH extramural grants given to study HHV-6 & 7 between 2000-2012 have been provided below. To determine whether herpes simplex virus (HSV)-1 and -2, varicella-zoster virus (VZV), HHV-6A, -6B, and -7, Epstein–Barr virus (EBV), and cytomegalovirus (CMV) DNA could be found in CSF of FP patients or controls. Another Japanese study of 105 CSF specimens from children with encephalopathy/encephalitis found 9.5% to be positive for HHV-6 and 1.9% for HHV-7 (Wada 2009). The complete genomic sequence of HHV-6 (variants A and B) and HHV-7 are now available [3–5]. In the 17 patients (179 specimens) in whom viral DNA in plasma was studied (in addition to PBL), a positive result was found only in 3. CMV-DNA was detected in two out of ten FUO-patients in all samples drawn during fever.


Recently, we reported that 1% of newborns have congenital human herpesvirus 6 (HHV-6) infection and that most of these congenital infections (86%) resulted from chromosomally integrated HHV-6 (CI-HHV-6) [1, 2]. Coinfection among these three β-herpesviruses in clinical syndromes that were classically ascribed to be solely caused by CMV has been shown and has raised substantial interest in the potential role of HHV-6 and HHV-7 as copathogens in the direct and indirect illnesses caused by CMV. Twenty-eight children (53.8%) were infected by HHV-6 earlier than HHV-7. HHV-6 commonly reactivates in transplant recipients. Finally, it is postulated that the suboptimal expression of native U51 may reflect a regulatory mechanism that controls viral gene expression. To provide better homogeneity between the results from the different laboratories working on HHV-6, we propose that investigators interested in quantifying HHV-6 in clinical samples adopt one of these assays. In contrast to studies of HHV-6 infection in organ-transplant recipients, the number of studies examining HHV-7 infection in these patients is limited.

According to our knowledge this well-documented case is probably the first report from Poland. All 7 normal tissues tested were negative for HHV-6. HHV-6A DNA (4,950 copies per ml) was detected in vitreous fluid from one patient with CMV retinitis, HHV-6B DNA (10,140 copies per ml) was detected in vitreous fluid from one patient with idiopathic ocular inflammation in the absence of CMV DNA, and HHV-7 was not detected any of the vitreous samples. Two subjects had HHV-6/HHV-7 primary coinfection at baseline. These findings suggested that the product of U12 may play an important role in the pathogenesis of HHV- 6 through transmembrane signaling by binding with β-chemokines. HHV-6B-infected HPDA showed no morphological changes, intracellular viral particles, and decreasing intra- and extracellular viral DNA over time. There is growing evidence for interactions among the β-herpesviruses (cytomegalovirus, HHV-6 and HHV-7), resulting in an increased risk of cytomegalovirus disease and opportunistic infections.

However, the majority of HHV-6 infections are asymptomatic. (4) Investigate the frequency and a possible role of the other novel lymphotropic herpesviruses, HHV-7 and HHV-8, in patients with multiple sclerosis. HHV-7 viremia at baseline was observed in 12 children (7.1%), including eight with primary infection and four with reactivated infection. Most adults (80%-90%) have been infected with this virus. (iii) A small number of T-cell clones (9 of 232) showed cross-reactivity against HHV-6 and HCMV, and 2 of the 232 clones were reactive with HCMV as well as with HHV-6 and HHV-7. T cells recognizing the recombinant 101-kDa protein (101K) corresponding to the major immunoreactive region unique to HHV-6 occurred at significantly lower precursor frequency in MS patients than in control subjects. 50 gener.

Currently clinicians rely mainly on blood lymphocyte culture and serological tests to diagnose HHV-6 infection. HHV-6 is a beta herpes virus that establishes latency after primary infection with most infections occurring in the childhood. PATIENTS: Neonates with fever with no other symptoms and neonates with fever with cerebrospinal fluid (CSF) pleocytosis.