Does urbanization make emergence of zoonosis more likely? Evidence, myths and gaps

Abstract

Rapid urbanization in the global South is adding epidemiological and nutritional challenges and increasing disease and health burdens for citizens. Greater movement of people, animals, food and trade often provides favourable grounds for the emergence of infectious diseases, including zoonoses. We conduct a rapid evidence scan to explore what is known and hypothesized about the links between urbanization and zoonosis emergence. This points to rapid demographic growth, migration and density, increased movement of people and animals, and changes in land uses as the main processes linked to the prevalence of zoonosis in the urban global South. We argue that this emerging global health challenge is also deeply connected with the urbanization of poverty and inequalities within cities. Tackling the micro-level causal relationships between urbanization and zoonosis requires urgent attention to living conditions, as well as the wider socioenvironmental transitions and structural drivers that produce and reproduce risk accumulation in urban settings.

Molecular detection of Rickettsia in fleas from micromammals in Chile

“…[30,31]. Rickettsia-positive eas parasitizing R. rattus in these three areas indicate that this species could play a key role in spreading the disease from wild to urban environments [16,32]. Conversely, we also observed that wild species enter human-occupied environments since they provide shelter and food.…”

“…This species has been described to have a "random walk" type of dispersal behavior, so it can easily go from wild to domestic environments [33]. These ndings are important because these rodent species could act as "bridge hosts" and aid in the spread of the disease [32,34]. On the other hand, in natural areas, the rodent species most frequently captured was A. hirta; this, like A. olivacea, had a high prevalence of Rickettsia-positive eas.…”

Molecular detection of Rickettsia in fleas from micromammals in Chile

“…This rodent was mainly captured in urban areas; however, we also found it in rural and natural areas, this occurs mainly because these rodents have an omnivore diet and plasticity in their behavior, characteristics that allow them to inhabit a great diversity of environments, adapting successfully to urban, rural and wild environments [30,31]. Rickettsia-positive eas parasitizing R. rattus in these three areas indicate that this species could play a key role in spreading the disease from wild to urban environments [16,32]. Conversely, we also observed that wild species enter humanoccupied environments since they provide shelter and food.…”

“…This species has been described to have a "random walk" type of dispersal behavior, so it can easily go from wild to domestic environments [33]. These ndings are important because these rodent species could act as "bridge hosts" and aid in the spread of the disease [32,34]. On the other hand, in natural areas, the rodent species most frequently captured was A. hirta; this species, like A. olivacea, had a high prevalence of Rickettsia-positive eas.…”

Molecular detection of Rickettsia in fleas from micromammals in Chile

“…This species has been described to have a "random walk" type of dispersal behavior, so it can easily go from wild to domestic environments [33]. These ndings are important because these rodent species could act as "bridge hosts" and aid in the spread of the disease [32,34]. On the other hand, in natural areas, the rodent species most frequently captured was A. hirta; this, like A. olivacea, had a high prevalence of Rickettsia-positive eas.…”