A Review of Emerging and Re- Emerging Zoonotic Viruses of the 21st Century Ryan F. Relich, PhD, D(ABMM), MLS(ASCP)SM Assistant Professor, Clinical Pathology and Laboratory Medicine Indiana University School of Medicine Section Director, Clinical Microbiology and Serology (Eskenazi Health) Section Director, Clinical Virology Laboratory (IU Health) Medical Director, Special Pathogens Unit Laboratory (IU Health) Associate Medical Director, Division of Clinical Microbiology (IU Health) Associate Medical Director, Division of Molecular Pathology (IU Health) Indianapolis, IN USA Disclosures and disclaimers • Research funding/support • Abbott, BD Diagnostics, Beckman Coulter, Cepheid, Luminex Corporation, Roche, Sekisui, STAT-Diagnostica • Travel support by First Coast ID/CM Symposium • PASCV sponsorship Objectives • At the end of this presentation, audience members will be able to: • Describe the basic biology, ecology, and epidemiology of the viruses discussed; • Identify factors associated with the emergence or re- emergence of zoonotic viruses; and, • List clinical features of diseases caused by several zoonotic viruses, as well as their detection, treatment, and prevention. Outline • What are emerging zoonotic viruses and where do they come from? • Overview / introduction to selected viruses • Role of applied and basic research in detecting and controlling these agents • Summary What are emerging pathogens? • “Infectious diseases whose incidence has increased in the past 20 years and could increase in the future.” • Caused by • Newly recognized pathogens • Old foes recurring in known endemic areas and/or new endemic areas Where do they come from? • The majority spill over from animals • Zoonotic infections 6 Where do they come from? • Many are transmitted directly from animal reservoirs to humans or to humans through one or more other animals (e.g., pigs, dogs, camels, ticks, etc.) • Others are maintained by arthropod-human-arthropod transmission 7 Why do they spill over? • Anthropogenic drivers • Encroachment into natural habitats • Introduction of viruses (and other microorganisms) into new geographic locations • Agricultural practices • Anthropogenic climate change 8 Why do they spill over? • Non-anthropogenic drivers • Movement of infected reservoirs and vectors into new areas • People can have a hand in this, too! • Adaptation of viruses to new vectors and other hosts 9 Arthropod-borne viruses • Arboviruses • These viruses persist in nature by • Cycling between competent arthropod vectors and other animals (e.g., NHPs, sloths, rodents, etc.) • Transovarial transmission (from dams to offspring) • After introduction into human populations, some establish vector-human-vector cycles 10 Arthropod-borne viruses • Mosquito-borne viruses • Dengue virus • Genus, Flavivirus; family, Flaviviridae • Non-segmented, (+)ssRNA • Enveloped particles • 5 serotypes • Dengue 1 – 5 ViralZone 11 Arthropod-borne viruses • Mosquito-borne viruses • Dengue virus • Causes dengue fever or “breakbone fever” • Febrile illness that can sometimes lead to severe disease and death • Dengue shock syndrome and hemorrhagic fever • Infection with one serotype does NOT protect you against infection with others 12 Arthropod-borne viruses • Mosquito-borne viruses • Dengue virus • Perhaps the most widely distributed arbovirus on the planet; several thousand deaths per year CDC Arthropod-borne viruses • Mosquito-borne viruses • Dengue virus • Vector: Aedes spp. (e.g., A. aegypti [L] and A. albopictus [R]) CDC CDC Arthropod-borne viruses • Mosquito-borne viruses • Chikungunya virus • Genus, Alphavirus; family, Togaviridae • Non-segmented, (+)ssRNA • Enveloped particles ViralZone Arthropod-borne viruses • Mosquito-borne viruses • Chikungunya virus • Found in both Eastern Hemisphere and Western Hemisphere • Arrived to Western Hemisphere in 2013 • Disease process • ~80% of those infected become symptomatic • Fever, joint pain, myalgia, rash • Post-infectious arthralgia can last for MONTHS Arthropod-borne viruses • Mosquito-borne viruses • Chikungunya virus • Same as for dengue virus CDC Arthropod-borne viruses • Tick-borne viruses • Bourbon virus • Genus, Thogotovirus; family, Orthomyxoviridae • Segmented, (-)ssRNA • Enveloped particles ViralZone Arthropod-borne viruses • Tick-borne viruses • Bourbon virus • To date, only a handful of reported human disease cases • Disease process • Unknown incubation period • Fever, malaise, maculopapular rash, polymyalgia, nausea, vomiting, diarrhea, ARDS, death • Leukopenia, thrombocytopenia, elevated liver enzymes Arthropod-borne viruses • Tick-borne viruses • Bourbon virus • Vector: likely Amblyomma americanum (lone star tick) http://heartspring.net/deer_tick_identification.html http://www.cdc.gov/ticks/maps/lone_star_tick.html Arthropod-borne viruses • Tick-borne viruses • Heartland virus • Genus, Banyangvirus; family, Phenuiviridae • Segmented, (-)ssRNA • Enveloped particles ViralZone Arthropod-borne viruses • Tick-borne viruses • Heartland virus • To date, only a handful of reported human disease cases • Disease process • Fever, fatigue, decreased appetite, headache, nausea, diarrhea, myalgia, and arthralgia • Leukopenia, thrombocytopenia, mildly elevated liver enzymes • A few deaths associated with infection Arthropod-borne viruses • Tick-borne viruses • Heartland virus • Vector: Amblyomma americanum (lone star tick) CDC Bat-borne viruses • Bats comprise the second-largest order of mammals • Over 1,200 species (account for about 20% of known species) • Massiveness of bat diversity means that there’s also a great deal of virus diversity • Some have proven to be dangerous human pathogens • Many “fly” under the radar, as they are nonpathogenic to humans • Many pathogens have yet to make contact contact with people and other susceptible hosts 24 Bat-borne viruses • Bat-borne viruses can either directly or indirectly spill over to humans • Direct: rabies virus and other encephalitogenic lyssaviruses; filoviruses, henipaviruses, etc. • Indirect: rabies virus, filoviruses, henipaviruses, various coronaviruses, etc. 25 Bat-borne viruses • Coronaviruses • Genus, Betacoronavirus; family, Coronaviridae • Enveloped particles • Monopartite (+)ssRNA • Particles have distinct morphology ViralZone Bat-borne viruses • Coronaviruses • Etymology • Corona = Latin noun, “crown” Wikipedia Beth Fischer, NIAID RML Bat-borne viruses • Coronaviruses • Middle East respiratory syndrome coronavirus (MERS-CoV or “Merbecovirus”) • First recognized in 2012 • Isolated from a Saudi Arabian patient’s sputum patient had pneumonia and renal failure • Clusters of cases in other parts of the Middle East (e.g., Jordan, Qatar, UAE, Yemen, etc.) --> sporadic cases outside of Middle East • 2015: large outbreak in South Korea Bat-borne viruses • Coronaviruses • MERS-CoV Virology Down Under 2019 Novel Coronavirus • 2019-nCoV • A ”new” betacoronavirus distantly related to SARS-like CoVs emerged in late 2019 (Wuhan, China) May and Relich. 2020. Unpublished. 2019 Novel Coronavirus • 2019-nCoV • A ”new” betacoronavirus distantly related to SARS-like CoVs emerged in late 2019 (Wuhan, China) May and Relich. 2020. Unpublished. 2019 Novel Coronavirus • 2019-nCoV • Currently, >12,000 cases in China and beyond • As of Jan 31, 2020 - 26 countries reporting cases 2019 Novel Coronavirus CDC (from Jan 31, 2020) 2019 Novel Coronavirus • 2019-nCoV • Currently, >12,000 cases in China and beyond • As of Jan 31, 2020 - 26 countries reporting cases • 7 confirmed cases in the U.S. 2019 Novel Coronavirus CDC (from Jan 31, 2020) 2019 Novel Coronavirus • 2019-nCoV • Currently, ~12,000 cases in China and beyond • As of Jan 31, 2020 - 26 countries reporting cases • 6 confirmed cases in the U.S. • Approximately >250 deaths (China) • Person-to-person transmission is possible Bat-borne viruses • Filoviruses • Currently, 6 recognized genera • Non-segmented (-)ssRNA • Enveloped particles • Filamentous morphology ViralZone 37 Bat-borne viruses • Filoviruses • Cuevavirus (1 species) • Dianlovirus (1 virus) • Ebolavirus (6 species) • Marburgvirus (1 species) • Striavirus (1 virus) • Thamnovirus (1 virus) 38 Bat-borne viruses • Filoviruses • Naturally found in the Eastern Hemisphere • Europe, Africa, China, Philippines, elsewhere? • Reston virus, Ebola virus, and Marburg virus have all been exported to non-native countries • Human-pathogenic filoviruses often cause severe disease • Ebola virus disease (Ebola hemorrhagic fever) • Marburg virus disease Bat-borne viruses • Filoviruses • Some (potential) reservoirs • Schreiber’s long-fingered bat (Miniopterus schreiberi) – LIoviu cuevavirus • Egyptian fruit bat (Rousettus egyptiacus) – Marburg virus • African and Asian fruit bats – a variety of ebolaviruses and Měnglà viruses Bat-borne viruses • Filoviruses Bat-borne viruses • Henipaviruses • Genus, Henipavirus; family, Paramyxoviridae • Non-segmented (-)ssRNA • Enveloped particles • So far, there are 5 named henipaviruses ViralZone 42 Bat-borne viruses • Henipaviruses • Cedar henipavirus • Ghanian bat henipavirus • Hendra henipavirus • Mojiang henipavirus • Nipah henipavirus 43 Bat-borne viruses • Henipaviruses • Hendra and Nipah viruses are found in Australia and Asia, respectively, and are reservoired by large fruit bats (flying foxes) • Pteropus spp. Pteropus lyeli (dukelanguage.com) Bat-borne viruses • Henipaviruses CDC Bat-borne viruses • Henipaviruses • Nipah virus • Causes respiratory and CNS disease in pigs and other animals • Humans have become infected by contact with infectious bat excrement