Alverston Bailey | Prevent future zoonotic pandemics
The world is now grappling with a global pandemic, severe acute respiratory syndrome coronavirus-2 (SARS CoV-2), and we must admit that we are now facing a crisis of biblical proportions; however, Paul Romer, a Stanford economist, in 2004 reminded us that “a crisis is a terrible thing to waste “.
Emerging diseases pose a global challenge, with some becoming epidemics (affecting a large number of people within a region), others becoming pandemics (spread over several countries and continents and affecting large numbers of people across the globe).
As we grapple with this pandemic, it behoves us to reflect on the musings of former National Security Adviser Donald Rumsfeld. He is quoted as saying “Reports that say that something hasn’t happened are always interesting to me, because as we know, there are known knowns; we also know there are known unknowns; but there are also unknown unknowns.” This quote elegantly describes the challenges posed by this pandemic, in that there are things we know that we know, there are some things we do not know, and there are ones we don’t know, we just don’t know.
The epidemiology of SARS CoV- 2 epitomises this dilemma of the knowns and unknowns, but I will use this medium to address the knowns.
Since December 31, 2019, and as of October 19, 2020, over 40 million people have been infected and over 1.1 million have died due to COVID-19 (in accordance with the applied case definitions and testing strategies in the affected countries) have been reported.
Pandemics are essentially man-made and is as a result of how we trade animals, source food, and destroy the environment.
In order to address this challenge, we must gain a deeper understanding of zoonoses.
A zoonosis (plural zoonoses, or zoonotic diseases) is an infectious disease caused by a pathogen (an infectious agent, such as a bacterium, virus, parasite or prion) that has jumped from a non-human animal (usually a vertebrate) to a human. The present data reveal that over 60 per cent of human infections have an animal origin and is the cause of about 75 per cent of all new and emerging human infections.
Some of the most severe zoonotic infections of the last century are:
Human immunodeficiency virus (HIV) infection; Avian infectious bronchitis; West Nile fever; Zika virus disease; Ebola virus disease; porcine epidemic diarrhoea; bovine spongiform encephalopathy, or mad cow disease; Hendra virus infection; highly pathogenic avian influenza (HPAI), or bird flu; Nipah virus infection, severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS); swine acute diarrhoea syndrome (SADS); coronavirus disease 2019 (COVID-19). These diseases were caused by: chimpanzees for HIV type 1, and Sooty Mangabey for HIV type 2; chickens, birds, primates, including humans, African fruit bats, pigs, cattle, flying foxes, wild waterfowls, horseshoe bats, masked civet cats, and dromedary camels.
There are many other zoonoses affecting humanity called the so-called ‘neglected zoonoses’. These are seen in many (mainly impoverished) populations, but receive much less international attention and funding than emerging zoonotic diseases. Here is a list of some neglected zoonoses: anthrax, bovine tuberculosis, brucellosis, rabies, cysticercosis (pig tapeworm), echinococcosis (hydatid disease), Japanese encephalitis, leptospirosis, Q fever, Lassa fever virus and trypanosomiasis (sleeping sickness). Most of these are spread by domestic animals, but several have a close association with wildlife.
Many studies on zoonotic disease emergence implicate the following seven main drivers:
1. Increasing demand for animal protein;
2. Unsustainable agricultural intensification;
3. Increased use and exploitation of wildlife;
4. Unsustainable utilisation of natural resources accelerated by urbanisation, land use change, and extractive industries;
5. Travel and transportation;
6. Changes in food supply chains; and
7. Climate change.
The Government of Jamaica should, therefore, implement, as a matter of urgency, these 10 policy recommendations as proposed by the United Nations Environment Programme:
Raise awareness and increase understanding of zoonotic and emerging disease risks and prevention. Increase investments in interdisciplinary approaches, recognising the interconnection between people, animals, plants, and their shared environment.
Expand scientific enquiry into the complex social, economic and ecological dimensions of emerging diseases, including zoonoses. Ensure ongoing and well-resourced preparedness and response mechanisms. Develop effective means of monitoring and regulating practices associated with zoonotic disease. Develop alternatives for food security and livelihoods that do not rely on the destruction and unsustainable exploitation of habitats and biodiversity. Identify key drivers of emerging diseases in animal husbandry. Reduce further destruction and fragmentation of wildlife habitat, and strengthen existing and build new capacities among health stakeholders.
Dr Alverston Bailey is associate professor in occupational health and safety at the School of Public Health and Health Technology, University of Technology, Jamaica. Send feedback to firstname.lastname@example.org.