A family of novel endotheliotropic herpesviruses (EEHVs) assigned to the genus Proboscivirus have been identified as the cause of fatal hemorrhagic disease in 70 young Asian elephants worldwide. Although EEHV cannot be grown in cell culture, we have determined a total of 378 kb of viral genomic DNA sequence directly from clinical tissue samples from six lethal cases and two survivors. Overall, the data obtained encompass 57 genes, including orthologues of 32 core genes common to all herpesviruses, 14 genes found in some other herpesviruses, plus 10 novel genes, including a single large putative transcriptional regulatory protein (ORF-L). On the basis of differences in gene content and organization plus phylogenetic analyses of conserved core proteins that have just 20% to 50% or less identity to orthologues in other herpesviruses, we propose that EEHV1A, EEHV1B, and EEHV2 could be considered a new Deltaherpesvirinae subfamily of mammalian herpesviruses that evolved as an intermediate branch between the Betaherpesvirinae and Gammaherpesvirinae. Unlike cytomegaloviruses, EEHV genomes encode ribonucleotide kinase B subunit (RRB), thymidine kinase (TK), and UL9-like origin binding protein (OBP) proteins and have an alphaherpesvirus-like dyad symmetry Ori-Lyt domain. They also differ from all known betaherpesviruses by having a 40-kb large-scale inversion of core gene blocks I, II, and III. EEHV1 and EEHV2 DNA differ uniformly by more than 25%, but EEHV1 clusters into two major subgroups designated EEHV1A and EEHV1B with ancient partially chimeric features. Whereas large segments are nearly identical, three nonadjacent loci totaling 15 kb diverge by between 21 and 37%. One strain of EEHV1B analyzed is interpreted to be a modern partial recombinant with EEHV1A. IMPORTANCEAsian elephants are an endangered species whose survival is under extreme pressure in wild range countries and whose captive breeding populations in zoos are not self-sustaining. In 1999, a novel class of herpesviruses called EEHVs was discovered. These viruses have caused a rapidly lethal hemorrhagic disease in 20% of all captive Asian elephant calves born in zoos in the United States and Europe since 1980. The disease is increasingly being recognized in Asian range countries as well. These viruses cannot be grown in cell culture, but by direct PCR DNA sequence analysis from segments totaling 15 to 30% of the genomes from blood or necropsy tissue from eight different cases, we have determined that they fall into multiple types and chimeric subtypes of a novel Proboscivirus genus, and we propose that they should also be classified as the first examples of a new mammalian herpesvirus subfamily named the Deltaherpesvirinae.
Ectoparasites frequently vector pathogens from often unknown pathogen reservoirs to both human and animal populations. Simultaneous identification of the ectoparasite species, the wildlife host that provided their most recent blood meal(s), and their pathogen load would greatly facilitate the understanding of the complex transmission dynamics of vector-borne diseases. Currently, these identifications are principally performed using multiple polymerase chain reaction (PCR) assays. We developed an assay (EctoBaits) based on in-solution capture paired with high-throughput sequencing to simultaneously identify ectoparasites, host blood meals and pathogens. We validated our in-solution capture results using double-blind PCR assays, morphology and collection data. The EctoBaits assay effectively and efficiently identifies ectoparasites, blood meals, and pathogens in a single capture experiment, allowing for high-resolution taxonomic identification while preserving the DNA sample for future analyses.
Summary Vegetation change in Queen Elizabeth National Park, W. Uganda between 1970 and 1988 was studied, mainly by comparison of photographs. Regeneration of Acacia spp. is widespread. Thickets dominated by Capparis tomentosa and Dichrostachys cinerea have spread, and their associated herbs are more diverse. Dry scrub forests have continued to decline. Fringes of Vossia cuspidata with shrubs such as Aeschynomene have developed at lake shores. Most of these changes can be attributed to the decline in elephant numbers, but a general reduction in large herbivore biomass may also be important. The possible consequences for tourism are discussed, and the importance of careful experimental design and site marking for long‐term Vegetation monitoring emphasized. Résumé On a étudié le changement de Végétation au Parc National Queen Elizabeth, à l'ouest de l'Uganda, principalement en comparant des photographies. La régénération d'Acacia spp. est très étendue. Les buissons où dominent Capparis tomentosa et Dichrostrachys cinerea se sont répandus et les herbes qui y sont associées se sont diversifiées. Les foréts de broussailles sèches ont continuéà décliner. Des franges de Vossia cuspidata avec des arbustes tels que Aeschynomene se sont développées au bord du lac. On peut attribuer la plupart de ces changements à la diminution du nombre des éléphants mais la baisse générale de la biomasse des herbivores est aussi importante. On discute des conséquences possibles sur le tourisme et on insiste sur l'importance d'un programme expérimental judicieux et du marquage de sites pour une surveillance continue à long terme de la Végétation.
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