Vanessa Olivia Ezenwa | |
---|---|
Alma mater | Princeton University Rice University |
Scientific career | |
Institutions | United States Geological Survey Odum School of Ecology Yale University |
Thesis | Behavioral and nutritional ecology of gastrointestinal parasitism in African bovids (2002) |
Vanessa Olivia Ezenwa is an American ecologist, and is a professor of ecology and evolutionary biology at Yale University. Her research considers the ecology of infectious diseases amongst animal populations. In 2020, she was selected by The Community of Scholars as one of the most Inspiring Black scientists in the United States.
As a high school student, Ezenwa became interested in infectious diseases and ecology. [1] Ezenwa earned her bachelor's degree at Rice University. She was a graduate student at Princeton University, where she majored in behavioral ecology. [2] [3] Her doctoral research considered eleven different species of African ungulate in Kenya. [1] Some of these ungulates lived in pairs, whilst some lived in groups of one hundred. [1] After completing her doctorate, Ezenwa joined the United States Geological Survey as a postdoctoral fellow. [4]
In 2005, Ezenwa joined the faculty at the University of Montana.[ citation needed ] She moved to the University of Georgia in 2010.[ citation needed ] Her research considers infectious diseases in animal populations, with a particular focus on identifying effective intervention strategies. She has studied how gastrointestinal worm infections impact the susceptibility of African buffalo to contract bovine tuberculosis, and how severe their diseases are once they have become infected. She concentrated her studies on the free ranging buffalo of Kruger National Park, but the buffalo are a major reservoir of bovine tuberculosis infections in South Africa. The prevalence of the disease in Africa can impact other wildlife. Ezenwa demonstrated that it was possible to treat the worms, diminishing the severity of tuberculosis and increasing the likelihood infected animals survive. Unfortunately, because infected animals survive better, they are more likely to spread the disease. [5] Ezenwa has investigated non-pharmaceutical approaches to managing infectious diseases amongst animals, such as test and cull programmes. [5] Beyond African buffalo, Ezenwa studied Grant's gazelle and spiny mice. [6] Ezenwa has investigated the influence of climate change and changing weather on infectious diseases amongst livestock. [7]
Ezenwa serves on the editorial advisory board of Science . [8] In 2020, Ezenwa was selected by The Community of Scholars as one of the most inspiring Black scientists in the United States. [9]
A human pathogen is a pathogen that causes disease in humans.
Tuberculosis (TB), also known colloquially as the "white death", or historically as consumption, is an infectious disease usually caused by Mycobacterium tuberculosis (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in which case it is known as latent tuberculosis. Around 10% of latent infections progress to active disease which, if left untreated, kill about half of those affected. Typical symptoms of active TB are chronic cough with blood-containing mucus, fever, night sweats, and weight loss. Infection of other organs can cause a wide range of symptoms.
The African buffalo is a large sub-Saharan African bovine. There are five subspecies that are recognized as being valid. Syncerus caffer caffer, the Cape buffalo, is the nominotypical subspecies, and the largest one, found in Southern Africa and East Africa. S. c. nanus is the smallest subspecies, common in forest areas of Central Africa and West Africa, while S. c. brachyceros is in West Africa and S. c. aequinoctialis is in the savannas of East Africa. The adult African buffalo's horns are its characteristic feature: they have fused bases, forming a continuous bone shield across the top of the head, referred to as a "boss".
An asymptomatic carrier is a person or other organism that has become infected with a pathogen, but shows no signs or symptoms.
Mycobacterium bovis is a slow-growing aerobic bacterium and the causative agent of tuberculosis in cattle. It is related to Mycobacterium tuberculosis, the bacterium which causes tuberculosis in humans. M. bovis can jump the species barrier and cause tuberculosis-like infection in humans and other mammals.
Paratuberculosis is a contagious, chronic and sometimes fatal infection that primarily affects the small intestine of ruminants. It is caused by the bacterium Mycobacterium avium subspecies paratuberculosis. Infections normally affect ruminants, but have also been seen in a variety of nonruminant species, including rabbits, foxes, and birds. Horses, dogs, and nonhuman primates have been infected experimentally. Paratuberculosis is found worldwide, with some states in Australia being the only areas proven to be free of the disease. At least in Canada, the signs of BJD usually start when cattle are four to seven years of age, and then usually only are diagnosed in one animal at a time. Cattle "with signs of Johne’s disease shed billions of bacteria through their manure and serve as a major source of infection for future calves."
Bovine alphaherpesvirus 1 (BoHV-1) is a virus of the family Herpesviridae and the subfamily Alphaherpesvirinae, known to cause several diseases worldwide in cattle, including rhinotracheitis, vaginitis, balanoposthitis, abortion, conjunctivitis, and enteritis. BoHV-1 is also a contributing factor in shipping fever, also known as bovine respiratory disease (BRD). It is spread horizontally through sexual contact, artificial insemination, and aerosol transmission and it may also be transmitted vertically across the placenta. BoHV-1 can cause both clinical and subclinical infections, depending on the virulence of the strain. Although these symptoms are mainly non-life-threatening it is an economically important disease as infection may cause a drop in production and affect trade restrictions. Like other herpesviruses, BoHV-1 causes a lifelong latent infection and sporadic shedding of the virus. The sciatic nerve and trigeminal nerve are the sites of latency. A reactivated latent carrier is normally the source of infection in a herd. The clinical signs displayed are dependent on the virulence of the strain. There is a vaccine available which reduces the severity and incidence of disease. Some countries in Europe have successfully eradicated the disease by applying a strict culling policy.
Bovine malignant catarrhal fever (BMCF) is a fatal lymphoproliferative disease caused by a group of ruminant gamma herpes viruses including Alcelaphine gammaherpesvirus 1 (AlHV-1) and Ovine gammaherpesvirus 2 (OvHV-2) These viruses cause unapparent infection in their reservoir hosts, but are usually fatal in cattle and other ungulates such as deer, antelope, and buffalo. In Southern Africa the disease is known as snotsiekte, from the Afrikaans.
Anaplasmosis is a tick-borne disease affecting ruminants, dogs, and horses, and is caused by Anaplasma bacteria. Anaplasmosis is an infectious but not contagious disease. Anaplasmosis can be transmitted through mechanical and biological vector processes. Anaplasmosis can also be referred to as "yellow bag" or "yellow fever" because the infected animal can develop a jaundiced look. Other signs of infection include weight loss, diarrhea, paleness of the skin, aggressive behavior, and high fever.
Bovine leukemia virus (BLV) is a retrovirus which causes enzootic bovine leukosis in cattle. It is closely related to the human T‑lymphotropic virus type 1 (HTLV-I). BLV may integrate into the genomic DNA of B‑lymphocytes as a DNA intermediate, or exist as unintegrated circular or linear forms. Besides structural and enzymatic genes required for virion production, BLV expresses the Tax protein and microRNAs involved in cell proliferation and oncogenesis. In cattle, most infected animals are asymptomatic; leukemia is rare, but lymphoproliferation is more frequent (30%).
A reverse zoonosis, also known as a zooanthroponosis or anthroponosis, is a pathogen reservoired in humans that is capable of being transmitted to non-human animals.
Disease is described as a decrease in performance of normal functions of an individual caused by many factors, which is not limited to infectious agents. Furthermore, wildlife disease is a disease when one of the hosts includes a wildlife species. In many cases, wildlife hosts can act as a reservoir of diseases that spillover into domestic animals, people and other species. Wildlife diseases spread through both direct contact between two individual animals or indirectly through the environment. Additionally, human industry has created the possibility for cross-species transmission through the wildlife trade.Furthermore, there are many relationships that must be considered when discussing wildlife disease, which are represented through the Epidemiological Triad Model. This model describes the relationship between a pathogen, host and the environment. There are many routes to infection of a susceptible host by a pathogen, but when the host becomes infected that host now has the potential to infect other hosts. Whereas, environmental factors affect pathogen persistence and spread through host movement and interactions with other species. An example to apply to the ecological triad is Lyme disease, where changes in environment have changed the distribution of Lyme disease and its vector, the Ixodes tick. The recent increase in wildlife disease occurrences is cause for concern among conservationists, as many vulnerable species do not have the population to recover from devastating disease outbreaks.
Bovine immunodeficiency virus (BIV) is a retrovirus belonging to the genus Lentivirus. It is similar to the human immunodeficiency virus (HIV) and infects cattle. The cells primarily infected are lymphocytes and monocytes/macrophages.
Dame Angela Ruth McLean is professor of mathematical biology in the Department of Biology, University of Oxford, and Chief Scientific Adviser to the UK Government.
In biology, a pathogen, in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ.
Sonia M. Altizer is the Georgia Athletic Association Professor of Ecology in the University of Georgia, Odum School of Ecology.
Lalita Ramakrishnan is an Indian-born American microbiologist who is known for her contributions to the understanding of the biological mechanism of tuberculosis. As of 2019 she serves as a professor of Immunology and Infectious Diseases at the University of Cambridge, where she is also a Wellcome Trust Principal Research Fellow and a practicing physician. Her research is conducted at the MRC Laboratory of Molecular Biology, where she serves as the Head of the Molecular Immunity Unit of the Department of Medicine embedded at the MRC LMB. Working with Stanley Falkow at Stanford, she developed the strategy of using Mycobacterium marinum infection as a model for tuberculosis. Her work has appeared in a number of journals, including Science, Nature, and Cell. In 2018 and 2019 Ramakrishnan coauthored two influential papers in the British Medical Journal (BMJ) arguing that the widely accepted estimates of the prevalence of latent tuberculosis—estimates used as a basis for allocation of research funds—are far too high. She is married to Mark Troll, a physical chemist.
Katie Jane Ewer is a British immunologist and Professor of Vaccine Immunology at the University of Oxford's Jenner Institute.
Penny M. Heaton is an American physician who is the Global Therapeutics Lead for Vaccines at Johnson & Johnson. She previously worked at Novavax, Novartis and the Bill & Melinda Gates Foundation. She was included by Stat News on their definitive list of leaders in the life sciences in 2022.
Wolves may suffer from various pathogens, both viral and bacterial, and parasite, both external and internal. Parasitic infection in wolves is of particular concern to people. Wolves can spread them to dogs, which in turn can carry the parasites to humans. In areas where wolves inhabit pastoral areas, the parasites can be spread to livestock.