The ecological context
Loretta A. Cormier, Pauline E. Jolly in The Primate Zoonoses, 2017
The World Health Organization (WHO) defines a zoonosis as any disease or infection that is naturally transmissible from vertebrate animals to humans (WHO 2016a). The phrase “naturally transmitted” excludes infections that are intentionally induced in laboratory settings. In the past, humans have also been the subject of experimental infection with animal pathogens. One example involves studies in the 1960s when over 200 prisoners were inoculated with various strains of wild primate malarias to determine if infections could be established in humans (Coatney 1968; Cormier 2011). Many species of wild primates have been used as models in the study of human diseases, particularly Rhesus macaques, chimpanzees, owl monkeys, and squirrel monkeys. However, acquisition under experimental conditions should not technically be considered cases of zoonotic or anthroponotic disease, although such studies can provide information about potential susceptibility.
Inflection points
J. Michael Ryan in COVID-19, 2020
Zoonosis occurs when a virus leaps from a nonhuman animal to a human, successfully establishing itself as an infectious presence that can cause mild or severe symptoms, or even death. Outside the worlds of virologists, veterinarians, ecologists, and public health officials, zoonosis is largely an unfamiliar word. Bubonic plague is a zoonosis, so too were the 1918 influenza pandemic, all influenzas, the swine flu, HIV, Ebola, SARS, MERS, Lyme disease, Marburg, and rabies (Quammen 2012; CDC 2020a; NIAID 2020). Different from predators that eat their prey from the outside, viruses are small and eat their prey from within. Under ordinary conditions, it is a natural occurrence. But, as Quammen (2012) pointed out, conditions are not always ordinary. Aberrations occur, circumstances change, and with them, the needs and opportunities for pathogens change, too.
Shellfish on the table not to blame for chronic cough in CÔte d'ivoire
Kristina Roesel, Delia Grace in Food Safety and Informal Markets, 2014
Zoonotic diseases are often under-diagnosed. One reason is that the symptoms are often similar to those of more common diseases and laboratory tests that would allow differential diagnosis are often not available or too expensive. Brucellosis is a good example; it is so often wrongly diagnosed as malaria that suspected cases of brucellosis are identified by medical history of ‘malaria that does not respond to anti-malarial treatment’. Twenty-one million people live in Côte d’Ivoire, 31,000 of whom are said to be infected with active tuberculosis.1 Chronic cough is one of the symptoms of tuberculosis, although it may be caused by other types of infection, for instance lung fluke infection. What if the chronic cough of these patients is due not to the bacterium that causes tuberculosis but to something else? The present study investigated the presence of lung flukes in shellfish sold in markets in and around Abidjan and the possible link between shellfish consumption and chronic cough in patients at tuberculosis centres.
Variant influenza: connecting the missing dots
Published in Expert Review of Anti-infective Therapy, 2022
Vivek Chavda, Rajashri Bezbaruah, Tutumoni Kalita, Anupam Sarma, Juti Rani Devi, Ratnali Bania, Vasso Apostolopoulos
The World Health Organization (WHO) recognized zoonosis as any infection or illness that could spontaneously be transmitted either from non-human vertebrates to humans or from the human population to animal species [1-3]. The word ‘zoonoses’ was derived using the Greek words ‘zoon,’ which denotes animal, and ‘nosos,’ which implies disease. Approximately 61% of the human pathogens are zoonotic [4,5]. Since all living beings, including both animals and humans as well as the environment, contribute to the pathogenesis and prevalence of the disease, it was reported that a significant percentage of infectious diseases that impact people are caused by animals [6]. In recent decades, human diseases of animal origin have evolved, and these diseases have been linked to animal origin diets. Some diseases, such as HIV infection, start out as zoonosis, but later the strains mutate and affect only humans. Zoonoses are a notable health concern as well as a direct human health risk that can cause death [7]. Additionally, the 13 most frequent zoonoses have had the greatest impact on poor livestock workers in economically developing countries, causing an estimated 2.4 billion infected cases of the disease and 2.7 million human deaths per year [8]. The majority of these diseases have a negative influence on animal health and reduce animal productivity considerably [4].
Current status of human rabies prevention: remaining barriers to global biologics accessibility and disease elimination
Published in Expert Review of Vaccines, 2019
Charles E. Rupprecht, Naseem Salahuddin
Rabies is an ancient, acute, progressive, fatal viral encephalitis. Annually, rabies continues to kill tens of thousands of people and exposes tens of millions of others. Many of these cases occur among children in lesser developed countries (LDCs) of Asia, Africa, and Latin America. Dogs are the primary reservoir, as well as wild mammalian carnivores and bats. Inexcusably, most people continue to die of rabies because they are exposed to unvaccinated rabid dogs and these bitten patients do not have easy access to modern, life-saving biologics. Although not a candidate for true eradication, this zoonosis can be prevented and controlled. Rapid, sensitive diagnostic tests and highly efficacious biologics do exist for human and veterinary applications. The basic root causes for current failures in laboratory-based surveillance and prophylaxis are nearly identical to other tropical diseases, such as basic neglect, poverty, regional strife and an overall lack of political will. The ‘Zero by Thirty’ is a renewed FAO, OIE, and WHO program focused upon the global elimination of human rabies mediated by dogs (GEHRD) through mass canine vaccination, pre-exposure rabies vaccination to populations at heightened risk and prompt, effective wound care, delivery of rabies immune globulin (RIG) and vaccine to exposed persons via an integrated animal bite management system of risk analysis.
SARS, MERS and SARS-CoV-2 (COVID-19) treatment: a patent review
Published in Expert Opinion on Therapeutic Patents, 2020
José Adão Carvalho Nascimento Junior, Anamaria Mendonça Santos, Lucindo José Quintans-Júnior, Cristiani Isabel Banderó Walker, Lysandro Pinto Borges, Mairim Russo Serafini
Ebola [73], severe acute respiratory syndrome (SARS) [74] and the coronavirus that emerged in China are all zoonotic viruses, being transmitted to humans by animals. SARS-CoV-2 [75] appears to have originated in a market in Wuhan, and preliminary information indicates its appearance in bats or pangolins [76]. Currently, about three out of four new diseases are zoonotic. Our demand for meat is increasing worldwide, and animal production is expanding as the economies in different parts of the world develop and produce increased demand for a meat-rich diet. Coronavirus is transmitted from wild animals to humans [76–78]. In China, meat and live animal markets are common in densely populated areas. This could explain why two of the most recent epidemics originated there [79]. In addition, as cities expand, we are pushed into rural areas where humans come into contact with wild animals. Lassa fever is a virus that spreads like this, when people clear forests to use the land for agriculture. To contain disease outbreaks, we depend on the government of the country where it originated. If the outbreak is neglected or not detected for 30 days, we run the risk of not containing its spread [80].