Scientists say the expansion of garbage dumps in low-income countries concentrates people, waste and animals in the same areas and dumps could be dangerous reservoirs for diseases such as Covid 19.
James Cook University Professor Bruce Gummow is a specialist in Veterinary Preventative Medicine (Epidemiology).
He is the co-author of a new study with Mahidol University in Thailand, of the interaction between waste, animals and the millions of people who make their living as garbage pickers – scouring rubbish dumps for material to resell or reuse.
He said an increasing trend in epidemics from zoonotic diseases, which jump from animals to humans, and emerging infectious diseases (EIDs) has been observed worldwide.
“Most EID outbreaks originate from wildlife, and these outbreaks often involve pathogen–host–environment interaction. Garbage dumps act as an interface between humans, animals, and the environment, from which EIDs could arise,” said Professor Gummow.
He said the team analysed nearly 350 scientific articles examining aspects of the situation.
“Compared to the natural environments, garbage dumps provide food for animals all year round. A high population density of multiple species at a dump site increases the rate of contact within and between species, allowing for the rapid transfer of pathogens and an increased chance of new pathogen strains emerging,” said Professor Gummow.
He said animals that visit garbage dumps were found to have a high prevalence of infectious diseases and many people who worked as garbage pickers did so in unhygienic, unhealthy conditions and are also generally in poor health.
“Most waste pickers in developing countries were informal workers who were unable to access proper healthcare and, as a result, could potentially carry diseases without being aware of it or able to do something about it if they were. They are at high risk while also being more likely to be exposed to different zoonotic pathogens,” said Professor Gummow.
He said garbage dumps may also facilitate the exchange of genetic material among bacteria, leading to the emergence of new, drug-resistant strains.
“By 2050, it’s estimated that cities will generate more than six million tons of solid waste per day. The percentage of organic matter in waste composition is high in low-income countries, with uncontrolled disposal, such as open dumps with open burning, a common practice,” said Professor Gummow.
He said a comprehensive examination of the disease ecology within garbage dumps is needed, coupled with sustainable waste management that reduces waste generation, and improves waste collection and disposal.
“We need to urgently reduce interaction between humans, animals, vectors, and pathogens in garbage dumps if our aim is to reduce the emergence of new diseases which can rapidly turn into global pandemics,” said Professor Gummow.
Link to paper here.