Novel betaherpesviruses and gammaherpesviruses in bats from central China.

Herpesviruses are large double-stranded DNA viruses that cause infections in animals and humans with a characteristic of latent infectious within specific tissues. Bats are natural hosts of variety human-infecting viruses and recently have been described as hosts for herpesviruses in several countries around the world. In this study we collected 140 insectivorous bats in the neighboring urban areas of Wuhan City, Hubei Province in the central China between 2020 and 2021. Nested PCR targeting the dpol gene sequence indicated that a total of 22 individuals (15.7% of the sample) tested positive for herpesvirus with 4 strains belonging to the genus Betaherpesvirus and the remaining 18 strains classified as Gammahersvirus. Furthermore, the herpesvirus prevalence in Rhinolophus pusillus was higher at 26.3%, compared to 8.4% in Myotis davidii. The RP701 strain from R. pusillus was the predominant gammaherpesvirus strain detected in bats, accounting for 94.4% (17/18) of all strains. The variations in γ-herpesviruses genomic sequences was evident in phylogenetic tree, where RP701 strain was clustered together with ruminant γ-herpesviruses, while MD704 strain formed a distinct clade with a hedgehog γ-herpesvirus. Four betaherpesviruses exclusively identified from M. davidii, with nucleotide identities ranging from 79.7 to 82.6% compared to known betaherpesviruses. Our study provided evidence that M. davidii can sever as natural host for ß-herpesviruses, which extended the host species range. In conclusion, we found that bats from central China harbored novel ß-herpesviruses and γ-herpesviruses which were phylogenetically related to ruminant γ-herpesvirus and hedgehog γ-herpesvirus. Our study indicates that bats are natural hosts of ß- and γ-herpesviruses and further studies are needed to determine whether there is cross-species transmission of herpesviruses between bats and other animals, or humans.

Diverse Beta- and Gammaherpesviruses in Neotropical Rodents from Costa Rica.

Neotropical wild rodents from Costa Rica were analyzed for the presence of herpesviruses (order Herpesvirales, family Herpesviridae). Using a broadly generic PCR, herpesvirus sequences were detected in 5% (8/160) of liver and heart samples: seven putative gammaherpesviruses in samples from Talamancan oryzomys (Nephelomys devius), sprightly colilargo (Oligoryzomys vegetus), Mexican deer mouse (Peromyscus nudipes), and Chiriqui harvest mouse (Reithrodontomys creper) and one putative betaherpesvirus in long-tailed singing mouse (Scotinomys xerampelinus). Results from this study could guide ecological investigations targeting the prevalence and host associations of herpesviruses in wild rodents from Costa Rica.

Clinical cystoisosporosis associated to porcine cytomegalovirus (PCMV, Suid herpesvirus 2) infection in fattening pigs.

Cystoisospora (syn. Isospora) suis is the causative agent of neonatal porcine coccidiosis and one of the main causes of diarrhoea in suckling piglets worldwide. Infection with porcine cytomegalovirus (PCMV, Suid herpesvirus 2) causes inclusion body rhinitis in pigs. In a Swiss pig herd (n=2 boars, 7 sows, 2 gilts, 18 finishing pigs, 30 fattening pigs, 54 suckling piglets), an outbreak of PCMV infection with high morbidity in all age categories, characterized by fever, anorexia, reduced general condition, respiratory signs and increased piglet mortality, was diagnosed by histopathology and molecular methods. Five fattening pigs (age~17weeks) additionally showed diarrhoea, not typical for PCMV infections, and one fattener had to be euthanized due to poor condition. Histopathologically, severe fibrinopurulent jejunoileitis with extensive atrophy and fusion of intestinal villi, loss of goblet cells and crypt abscesses associated to C. suis infection were present. In the liver, herpesvirus intranuclear inclusion bodies were observed and PCMV was confirmed by PCR/sequencing. No further infectious causes of diarrhoea (i.e. Rotavirus A; TGEV; PEDV; PCV-2; enterotoxigenic Escherichia coli or Lawsonia intracellularis) were detected in the euthanized fattener. Coproscopically, C. suis oocysts were identified in the faeces from further fatteners with diarrhoea. While C. suis usually produces disease only in suckling piglets, its association with severe intestinal lesions and diarrhoea in ~17-week-old fatteners was surprising. It is supposed that the underlying PCMV infection might have contributed to the presentation of clinical cystoisosporosis in fattening pigs. The interaction mechanisms between these two pathogens are unknown.

Discovery of herpesviruses in Canadian wildlife.

Herpesviruses (HVs) have a wide range of hosts in the animal kingdom. The result of infection with HVs can vary from asymptomatic to fatal diseases depending on subtype, strain, and host. To date, little is known about HVs naturally circulating in wildlife species and the impact of these viruses on other species. In our study, we used genetic and comparative approaches to increase our understanding of circulating HVs in Canadian wildlife. Using nested polymerase chain reaction targeting a conserved region of the HV DNA polymerase gene, we analyzed material derived from wildlife of western and northern Canada collected between February 2009 and Sept 2014. For classification of new virus sequences, we compared our viral sequences with published sequences in GenBank to identify conserved residues and motifs that are unique to each subfamily, alongside phylogenetic analysis. All alphaherpesviruses shared a conserved tryptophan (W856) and tyrosine (Y880), betaherpesviruses all shared a serine (S836), and gammaherpesviruses had a conserved glutamic acid (E835). Most of our wildlife HV sequences grouped together with HVs from taxonomically related host species. From Martes americana, we detected previously uncharacterized alpha- and beta-herpesviruses.

Identification of Novel Betaherpesviruses in Iberian Bats Reveals Parallel Evolution.

A thorough search for bat herpesviruses was carried out in oropharyngeal samples taken from most of the bat species present in the Iberian Peninsula from the Vespertilionidae, Miniopteridae, Molossidae and Rhinolophidae families, in addition to a colony of captive fruit bats from the Pteropodidae family. By using two degenerate consensus PCR methods targeting two conserved genes, distinct and previously unrecognized bat-hosted herpesviruses were identified for the most of the tested species. All together a total of 42 potentially novel bat herpesviruses were partially characterized. Thirty-two of them were tentatively assigned to the Betaherpesvirinae subfamily while the remaining 10 were allocated into the Gammaherpesvirinae subfamily. Significant diversity was observed among the novel sequences when compared with type herpesvirus species of the ICTV-approved genera. The inferred phylogenetic relationships showed that most of the betaherpesviruses sequences fell into a well-supported unique monophyletic clade and support the recognition of a new betaherpesvirus genus. This clade is subdivided into three major clades, corresponding to the families of bats studied. This supports the hypothesis of a species-specific parallel evolution process between the potentially new betaherpesviruses and their bat hosts. Interestingly, two of the betaherpesviruses' sequences detected in rhinolophid bats clustered together apart from the rest, closely related to viruses that belong to the Roseolovirus genus. This suggests a putative third roseolo lineage. On the contrary, no phylogenetic structure was detected among several potentially novel bat-hosted gammaherpesviruses found in the study. Remarkably, all of the possible novel bat herpesviruses described in this study are linked to a unique bat species.

Detection and evaluation of novel herpesviruses in routine and pathological samples from Asian and African elephants: identification of two new probosciviruses (EEHV5 and EEHV6) and two new gammaherpesviruses (EGHV3B and EGHV5).

Systemic infections with elephant endotheliotropic herpesviruses (EEHV) cause a rapid onset acute hemorrhagic disease with an 85% mortality rate. More than 60 cases have been confirmed worldwide occurring predominantly in juvenile Asian elephants. Originally, three virus types EEHV1A, EEHV1B and EEHV2 were identified, all members of the Proboscivirus genus within the Betaherpesvirinae. However, four elephant gammaherpesviruses (EGHV) have also been found by DNA PCR approaches in eye and genital secretions of asymptomatic animals, and two more versions of the probosciviruses, EEHV3 and EEHV4, were recently detected in acute hemorrhagic disease cases. To ask whether even more species of elephant herpesviruses may exist, we have developed several new diagnostic DNA PCR assays using multiple round primers in the DNA POL region. These have been used routinely for nearly three years to screen samples submitted to the Elephant Herpesvirus Laboratory for diagnosis of possible cases of EEHV disease in blood and necropsy tissue, as well as in biopsies of other suspicious lesions or growths. Several more cases of EEHV1-associated hemorrhagic disease were confirmed, but in addition, we describe here eleven examples of other known and novel herpesviruses detected and evaluated with these reagents. They include the prototypes of four new elephant herpesviruses, two more within the proboscivirus group EEHV5 and EEHV6, plus two more gammaherpesviruses EGHV3B and EGHV5. We also report initial semi-quantitative PCR assays demonstrating very high viral loads in the blood of the EEHV3 and EEHV4-associated hemorrhagic disease cases.

Identification of a novel betaherpesvirus in Mus musculus.

Rodent betaherpesviruses vary considerably in genomic content, and these variations can result in a distinct pathogenicity. Therefore, the identification of unknown betaherpesviruses in house mice (Mus musculus), the most important rodent host species in basic research, is of importance. During a search for novel herpesviruses in house mice using herpesvirus consensus PCR and attempts to isolate viruses in tissue culture, we identified a previously unknown betaherpesvirus. The primary PCR search in mouse organs revealed the presence of known strains of murine cytomegalovirus (Murid herpesvirus 1) and of Mus musculus rhadinovirus 1 only. However, the novel virus was detected after incubation of organ pieces in fibroblast tissue culture and subsequent PCR analysis of the supernatants. Long-distance PCR amplification including the DNA polymerase and glycoprotein B genes revealed a 3.4 kb sequence that was similar to sequences of rodent cytomegaloviruses. Pairwise sequence comparisons and phylogenetic analyses showed that this newly identified murine virus is most similar to the English isolate of rat cytomegalovirus, thereby raising the possibility that two distinct CMV lineages have evolved in both Mus musculus and Rattus norvegicus.

Beta-herpesviruses in febrile children with cancer.

We conducted a cross-sectional study of beta-herpesviruses in febrile pediatric oncology patients (n = 30), with a reference group of febrile pediatric solid-organ transplant recipients (n = 9). One (3.3%) of 30 cancer patients and 3 (33%) of 9 organ recipients were PCR positive for cytomegalovirus. Four (13%) of 30 cancer patients and 3 (33%) of 9 transplant recipients had human herpesvirus 6B (HHV-6B) DNAemia, which was more common within 6 months of initiation of immune suppression (4 of 16 vs. 0 of 14 cancer patients; p = 0.050). HHV-6A and HHV-7 were not detected. No other cause was identified in children with HHV-6B or cytomegalovirus DNAemia. One HHV-6B-positive cancer patient had febrile disease with concomitant hepatitis. Other HHV-6B-positive children had mild "viral" illnesses, as did a child with primary cytomegalovirus infection. Cytomegalovirus and HHV-6B should be included in the differential diagnosis of febrile disease in children with cancer.

Discovery of herpesviruses in bats.

Seven novel gammaherpesviruses (GHV) and one novel betaherpesvirus were discovered in seven different European bat species (order Chiroptera, family Vespertilionidae) with a pan-herpesvirus PCR assay, targeting the DNA polymerase (DPOL) gene. The sequences of six bat GHV were similarly related to members of the gammaherpesvirus genera Percavirus and Rhadinovirus. The seventh GHV was related to the porcine lymphotropic herpesvirus 1 (genus Macavirus). The betaherpesvirus appeared to be a distant relative of human cytomegalovirus. For three bat GHV a 3.6 kbp locus was amplified and sequenced, spanning part of the glycoprotein B gene and the majority of the DPOL gene. In phylogenetic analysis, the three bat GHV formed a separate clade with similar distance to the Percavirus and Rhadinovirus clades. These novel viruses are the first herpesviruses to be described in bats.

Infliximab and the risk of latent viruses reactivation in active Crohn's disease.

BACKGROUND: Infliximab is used for refractory Crohn's disease but there are concerns regarding long-term safety. Recently, JC-polyomavirus (JCV) was studied after 3 cases of progressive multifocal leukoencephalopathy (PML) were found after treatment with natalizumab. The aim of this study was to investigate the short-term effect of infliximab on reactivation of several harmful latent viruses. METHODS: Sixty consecutive patients scheduled for infliximab induction course were prospectively enrolled. Blood samples were taken before each infliximab infusion at 0, 2, 6, and 14 weeks. Specific polymerase chain reaction (PCR) analyses were performed to detect JCV, Epstein-Barr virus (EBV), human herpes virus-6, (HHV-6), -7, -8, and cytomegalovirus (CMV). RESULTS: Indications to infliximab were luminal and fistulizing disease in 49 and 15 cases, respectively. Clinical improvement and remission were achieved in 54 (90%) and 39 (65%) of patients, respectively, at 6 weeks. No patient was JCV-positive at any timepoint. EBV serology was positive for 59/60 patients (98%); EBV-PCR tests were transiently positive (>40 copies/10(5) Peripheral blood mononuclear cells, PBMC) in 4 (7%) patients after infliximab, but in each case were negative at subsequent timepoints. All patients were negative for HHV-6, -7, and -8 at all timepoints. CMV serology was positive in 42 patients (70%), but no CMV-PCR-positive patient was observed. There was no association between concomitant treatments or clinical characteristics and viral status. CONCLUSIONS: Our results support the safety of short-term infliximab treatment with respect to latent virus reactivation. The long-term effects of infliximab, particularly for the issue of lymphoproliferative disorders, warrants further studies with larger populations, but so far data are reassuring.

Determination of the six major human herpesviruses in cerebrospinal fluid and blood specimens of children.

AIM: To detect and differentiate six major human herpesviruses in the cerebrospinal fluid (CSF) and blood of children by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). METHODS: We synthesized two pairs of primers in the well-conserved regions of the DNA polymerase gene in human herpesviruses. One pair was designed to amplify cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), and the other pair to amplify varicella-zoster virus (VZV) and human herpesvirus 6 (HHV-6) by PCR. Virus species identification was achieved by restriction enzyme digestion with BamHI and BstUI. Ninety-eight CSF and 75 blood specimens were analysed by this technique. At the same time, all blood specimens were also examined by enzyme-linked immunosorbent assay (ELISA). RESULTS: Thirteen (13.3%) of 98 CSF specimens and 26 (34.7%) of 75 blood specimens were positive for herpesvirus DNA in this PCR assay. Only 10 (13.3%) of the blood specimens were positive in ELISA for virus-IgM antibody. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of PCR in detecting herpesvirus infections compared with ELISA were 100% (10/10), 75.4% (49/65), 38.5% (10/26) and 100% (49/49), respectively. These results indicate that the positive rate of PCR was significantly higher than that of ELISA (p < 0.05). The herpesvirus type of these positive specimens was rapidly detected using restriction enzyme digestion with BamHI and BstUI. CONCLUSIONS: PCR-RFLP is a specific, sensitive and accurate technique for the identification of herpesvirus infections in the CSF and blood of children.

Search for viruses in the CSF of patients with acute neurological disorders: possible involvement of beta-and gamma-herpesviruses.

In the years 1999-2001, 868 samples of cerebrospinal fluid (CSF) from as many patients with acute neurological manifestations of suspected viral origin were analysed for the presence of viruses at the Centre for the Diagnosis of Viral Diseases of the University of Modena and Reggio Emilia. Neurological patients included 788 immunocompetent subjects and 80 patients with impaired immunity due to human immunodeficiency virus (HIV) seropositivity. Of the CSF samples, 125 (15.8%) were positive for one or more viruses among the immunocompetent patients, whereas 33 (41.1%) were positive among the HIV cohort. DNA and RNA viruses were detected in the first group of CSF samples whereas only DNA viruses were found in the second group. In immunocompetent patients the frequency of enteroviruses prevailed over that of other RNA virus families (p = 0.001) and that of herpesviruses over the frequency of other DNA virus families (p = 0.001). Among herpesvirus members, the Epstein-Barr gamma-herpesvirus prevailed on alpha-herpesviruses in each of the two groups of patients (p = 0.05 in the immunocompetent group and p = 0.006 in HIV-positive patients). The clinical relevance both of this virus and of beta-herpesviruses as a cause of neurological disorders is discussed.

Structural organization and analysis of the viral terminase gene locus of Tupaia herpesvirus.

Tupaia herpesvirus (THV) was isolated from spontaneously degenerating tissue cultures of malignant lymphoma, lung, and spleen cell cultures of tree shrews (Tupaia spp.). In order to determine the phylogenetic relatedness of THV the complete nucleotide sequence of the viral terminase (VTER) gene locus (6223 bp) of Tupaia herpesvirus strain 2 (THV-2) was elucidated and analysed. The VTER gene locus, encoding one of the most highly conserved herpes viral proteins is composed of two exons. The intron contains five potential open reading frames (ORFs). The arrangement of these ORFs is colinear with the corresponding regions in the genomes of the mammalian cytomegaloviruses. The precise primary structure of the THV-2 VTER splice junction was determined using RT-PCR and was found to be in agreement with the corresponding splice donor and acceptor sites of the mammalian cytomegaloviruses. The comparison of all six putative THV-2 proteins with the corresponding counterparts in other herpesviruses revealed that THV resides between the Human and the Murine cytomegalovirus (HCMV, MCMV). These results are in agreement with our previous statement, that THV and the known cytomegaloviruses are closely related to each other and should be classified into one taxonomic group. The genetic data presented here and in previous studies are based on the detailed comparison of highly conserved viral genes. Consequently, the classification of the Human and the cytomegaloviruses into the two genera Cyto- and Muromegalovirus, that is mainly based on overall genome structure, should be reconsidered.

Simian homologues of human gamma-2 and betaherpesviruses in mandrill and drill monkeys.

Recent serological and molecular surveys of different primate species allowed the characterization of several Kaposi's sarcoma-associated herpesvirus (KSHV) homologues in macaques, African green monkeys, chimpanzees, and gorillas. Identification of these new primate rhadinoviruses revealed the existence of two distinct genogroups, called RV1 and RV2. Using a degenerate consensus primer PCR method for the herpesvirus DNA polymerase gene, the presence of KSHV homologues has been investigated in two semi-free-ranging colonies of eight drill (Mandrillus leucophaeus), five mandrill (Mandrillus sphinx), and two hybrid (Mandrillus leucophaeus-Mandrillus sphinx) monkeys, living in Cameroon and Gabon, Central Africa. This search revealed the existence of not only two distinct KSHV homologues, each one belonging to one of the two rhadinovirus genogroups, but also of two new betaherpesvirus sequences, one being close to cytomegaloviruses and the other being related to human herpesviruses 6 and 7 (HHV-6 and -7). The latter viruses are the first simian HHV-6 and -7 homologues identified to date. These data show that mandrill and drill monkeys are the hosts of at least four novel distinct herpesviruses. Moreover, mandrills, like macaques and African green monkeys, harbor also two distinct gamma-2 herpesviruses, thus strongly suggesting that a second gamma-2 herpesvirus, belonging to the RV2 genogroup, may exist in humans.

Presence of human beta- and gamma-herpes virus DNA in Hodgkin's disease.

Herpes viruses have been implicated in the etiology of Hodgkin's disease (HD). We studied the prevalence of human cytomegalovirus (CMV), human herpes viruses type-6 (HHV-6), type-7 (HHV-7) and type 8 (HHV-8) DNA in up to 88 Hodgkin's disease biopsies in comparison to Epstein-Barr virus (EBV) DNA by polymerase chain reaction (PCR). Non-Hodgkin lymphomas (NHL) and reactive lesions served as controls. CMV and HHV-6 were found in 8/86 (9%) and 11/88 (13%) HD cases, respectively, by nested primer PCR. Except for three cases harbouring HHV-6 type-B, only HHV-6 type-A was detected in HD. HHV-7 was observed by nested PCR in 33/88 (38%) HD cases and was already detectable in 15/88 (17%) HD cases by a single-round PCR indicating elevated virus copy numbers. Seven of these cases showed co-infection with HHV-6, and 11 cases were found to contain EBV DNA. 7/8 CMV-positive HD cases also harboured EBV DNA. HHV-8 DNA was not detected by single round or nested PCR in any HD case investigated. Thus, CMV, HHV-6, and HHV-7 were present in small proportions of HD cases, with frequent co-infection of HHV-6 and HHV-7, and frequent association with EBV. In contrast to EBV, beta-herpes viruses are therefore unlikely to have a role in the aetiology of HD. Rather, the presence of these viruses seems to reflect impaired immunological surveillance.

Infección congénita por citomegalovirus

El citomegalovirus (CMV) se encuentra ampliamente distribuido en la población, es el responsable de graves infecciones especialmente congénitas y es considerado como un problema médico-biológico debido al poco conocimiento de la epidemiología de la infección latente (1-5). El CMV es un ADN virus miembro de la subfamilia Betaherpesvirinae, con una gran capacidad para adaptarse y permanecer latente y presentar reactivaciones en situaciones en que esté alterada la respuesta inmune, por lo que se ha considerado como un verdadero marcador de inmunodeficiencia (6-9). Su incidencia es variable, oscila entre 1 y 5 por ciento. La enfermedad por citomegalovirus es subclínica en un 90 por ciento de los casos y de éstos el 10 por ciento tienen secuelas neurológicas. El CMV ataca la matriz germinal ependimaria y la sustancia blanca produciendo lesiones de necrosis, calcificación, disgenesia cerebral, microcefalia, micropoligiria que se traduce en retardo mental, convulsiones, displejía espástica (5, 10-12). El diagnóstico no sólo es clínico, sino virológico inmunológico, histológico y escanográfico. El tratamiento es multidisciplinario y el pronóstico depende del compromiso neurológico (9, 13-15). Con el objeto de resaltar las manifestaciones neurológicas en los pacientes pediátricos infectado por el CMV, presentamos estas cuatro casos clínicos que consultaron el servicio de neurología infantil del Hospital Universitario de Cartagena.