Biology subjects

Hayward, G. S.

Publications and source records attributed to Hayward, G. S..

3 recordsLinked to original sources

bioRxiv2026

PERSISTENT LOW-LEVEL INFECTIONS OF ELEPHANT ENDOTHELIOTROPIC HERPESVIRUS AND ELEPHANT GAMMAHERPESVIRUSDETECTED IN SKIN NODULES AND SALIVA FROM WILD AND ZOO AFRICAN ELEPHANTS

The goal of this study was to determine which species of Elephant Endotheliotropic Herpesviruses (EEHV) and Elephant Gammaherpesviruses (EGHV) are endemic in wild African elephants, Loxodonta. We collected skin nodule biopsies, saliva and tissues from 43 wild L. africana (African bush elephant) in Botswana, Kenya, South Africa and Zimbabwe; and saliva from 25 wild L. cyclotis (African forest elephant) in Gabon. We also collected saliva over seven years from 7 wild-born L. africana at Six Flags Safari Park, USA, and saliva, blood and tissues from an additional 200 L. africana and Elephas maximus in USA zoos. Conventional polymerase chain reaction and Sanger sequencing of purified DNA from these samples yielded thousands of unambiguous positive genetic matches to known EEHV2, EEHV3A, EEHV3B, EEHV6, EEHV7A, EGHV2, EGHV3B, EGHV4B, EGHV5B, and discovered new species EEHV3C-H, EEHV7B and EGHV1B in African elephants, and EGHV5A in an Asian elephant. Our extensive library of EEHV and EGHV sequences from wild and zoo elephants provide a significant resource to the elephant virologists and conservationists.

molecular biology↗

bioRxiv2024

Quiescent Infections of Elephant Endotheliotropic Herpesviruses and Elephant Gammaherpesviruses in African Elephants in Botswana, Gabon, Kenya, South Africa and USA

This novel study detected persistent low-level infection of Elephant Endotheliotropic Herpesviruses (EEHV), that can cause highly pathogenic Elephant Hemorrhagic Disease (EHD) in Loxodonta and Elephas, and co-infection of presumed less pathogenic Elephant Gammaherpesviruses (EGHV), in skin nodule biopsies, saliva and tissues collected from 43 wild L. africana (savannah elephant) in Botswana, Kenya, South Africa and Zimbabwe; in saliva from 25 wild L. cyclotis (forest elephant) in Gabon and 7 wild-born L.africana at Six Flags Safari Park, USA, over an extended period of seven years; and in saliva, blood and tissues from an additional 200 L. africana and 100 Elephas maximus in USA zoos. DNA from these samples was extracted in our USA laboratories and amplified by conventional polymerase chain reaction using three-round nested primer sets designed specifically to screen for known EEHV and EGHV genes loci and to discover new species and subtypes. Sanger sequencing of purified DNA from nearly all samples yielded unambiguous positive genetic matches to previously known Loxodonta-associated EEHV2, EEHV3A, EEHV3B, EEHV6, EEHV7A, and EGHV1B, EGHV2, EGHV3B, EGHV4B, EGHV5B and discovered novel types EEHV3C-H and EEHV7B and the prototype EGHV1B. Many of the primer sets used could also have detected known Elephas-associated EEHV1A, EEHV1B, EEHV4, and EEHV5 if present, but they did not. This extensive EEHV and EGHV sequence library will be a significant contribution to the elephant virology community.

molecular biology↗

bioRxiv2024

Epidemiological, Serological, and Virological Analysis of an Outbreak of Elephant Hemorrhagic Disease in Switzerland

Elephant hemorrhagic disease (EHD), caused by several Elephant endotheliotropic herpesviruses (EEHV), represents a frequently lethal syndrome, affecting both captive and free-living elephants. In summer 2022, three young Asian elephants (Elephas maximus) succumbed to EHD in a zoo in Switzerland, despite of considerable preventive efforts and early detection of EEHV1A viremia. In this communication, we describe the extent of preventive measures in terms of prior virus detection, active survey of viremia, and antibody status. In the course of the outbreak, the causative virus was concomitantly analyzed and eventually fully sequenced and compared to other EEHV types and strains. The conclusions from these analyses may be summarized in three points: (1) A previously undetected EEHV1A strain had remained unrecognized among these elephants. Probably, the new virus re-emerged after almost 40 years of latency from one of the oldest elephants in the zoo. (2) While two of the three affected animals had prior immune responses against EEHV1, their strain-specific immunity proved insufficient to prevent EHD. (3) There is an urgent need to develop efficient antiviral drugs and protective vaccines. In particular, ways need to be found to circumvent the present unavailability of appropriate cell cultures and animal models.

microbiology↗