Michael Smith, Intern 2016-2017
Silence is golden, right? For many, peace and quiet at the end of a long day is a much cherished commodity. As a city dweller, I’m always shocked by how quiet it is at my parents home in upstate New York. I awake to birds chirping, deer pleasantly munching in the yard—and the comfort knowing I will probably not hear a cacophony of sirens, car horns, and bus engines outside. Despite the noise, however, there are many advantages to city life - access to expansive public transportation infrastructure, myriad cultural centers and institutions, a continuous exchange of ideas between people - it is no wonder why city and urban living is on the rise. Ensuring that these urban centers are safe and secure places to live, however, requires more than just a robust police force, it requires officials to view public health in a new way.
The rise of cities
More people are living in cities than ever. For the first time, more than 50 percent of the human population lives in cities - that’s over four billion people - and further growth is expected. The world’s urban population is projected to surpass six billion people by 2045. More than two-thirds of all humans will be living in urban environs - leading to an inevitable increase of human exposure to pollution and contagion.
The United Nations has documented the recent rise of so-called “mega-cities” (metropolises of ten million inhabitants or more) like Mexico City, Mumbai, Osaka, Beijing and Cairo. In 1990 there were only ten mega-cities globally - now, there are 28. As the prevalence of mega-cities grows, so does our collective concern about the rise of epidemics in dense, highly-populated urban centers, where contagion can spread fast and far, threatening urban security as we know it.
But, rising global populations aren’t the only concern - other, more recent pressures, like human migration and climate change, combine to create a milieu of novel health concerns that affect the entire globe.
Summary of pressures
We can summarise these issues into the convergence of two main crises: ecology and medicine. In one camp, we see ecological perturbations - population growth, increasing global temperatures encroaching into new and more rural environments, and global travel. In the medical camp, we see increasing anti-vaccination sentiment, decreasing rates of vaccination and immunization coverage, as well as the lack of proper medical and health infrastructure in the communities and regions that need it most.
Ideally, larger, wealthier cities should be better suited to cope with infectious disease. Cities and urban settings should be more secure than rural areas when it comes to understanding and containing disease. Wealthy urban centers are better positioned to provide health security: a more robust health infrastructure coupled with more money, better facilities and reliable services (think: electricity, waste-water management, sanitation, refrigeration, better hygiene).
Not surprisingly, when low-resource countries and regions with weak health care systems also have large urban populations, viruses like Ebola and Zika can devastate and decimate with little warning, and quickly. A virus like Ebola, by epidemiological standards, is actually rather difficult to spread - the virus can only be spread when in direct contact with bodily fluids. It cannot be spread by air, water or through food - but in a dense population with little to no infrastructure, it spreads like wildfire.
Lack of medical professionals
Often, there is a dearth of qualified medical experts in key outbreak regions resulting in understaffed and underfunded medical centers. The World Health Organization has estimated that there will be a shortage of over twelve million health workers in the year 2035. Another legitimate issue that needs to be addressed is health worker migration (when a health professional moves out of the country to practice) - especially if accurate and timely action is needed to identify and contain an outbreak.
What’s more, weak and ineffective health systems are further crippled by increasing population density—and this means we cannot prevent or control outbreaks as easily. The reality is that outbreaks will always happen,and often, there is little we can do to stop them. However, pandemics should be optional.We have the ability to halt the global spread of disease. In order to limit that spread, we need to have a closer look at what we are doing as a species that is contributing to the likelihood that a major outbreak of disease will occur.
More extreme interaction with the environment
As an example, in Africa, the number of people is expected to double by the year 2050 - desertification is expected to drive and displace an additional 60 million people towards urban center by 2020. African cities like Lagos, which already is one of the largest cities in the world, will continue to grow as pressure from land degradation, conflict, famine, rising sea levels will inevitably create a more competitive space for land use.
Environmental changes lead to spillover
These population-based forces and environmental shifts are forcing people to move into new habitats and encroach into new territories. Humans are interacting with more animals than ever - we are driving animals away from their natural habitats by expanding our cities, and through the destruction of forests, shrinking the space between humans and animals. As our interaction and admixture increases, more and more contact creates an increased likelihood for zoonotic spillover - when a disease passes from one animal species to humans (think: Ebola from bats, HIV from chimpanzees, Zika from mosquitos, Lyme disease from deer). The truth is that these disease do not just happen to us as out of nowhere. We as a species are doing things that make these conditions rife and fertile for outbreak and spread. And like these diseases, humans as a species, like to move around, too.
Contributions from travel
The transmission and movement of peoples is also greater now than ever before - global travel is at an all-time high; according to the United Nations World Tourism Organization, nearly 1.3 billion people travelled internationally in 2015. Geographical and political boundaries mean little when human movement is so frequent and vast - and when over seven billion are travelling or being visited by friends, family and colleagues - contagion and the spread of pathogens occurs more easily and more widely than ever before.
Summary of issues
As humans continue to encroach into the natural habitats of animals and extend our reach around the globe through air travel, these issues will come together into a highly volatile situation. More people inhabiting less space, which places further strain on already limited sanitation infrastructure, all while displacing native animals and degrading green space fosters a climate that encourages the spread of disease through a myriad of vectors.
Sprinkle in anti-vaccination sentiment and veracious public campaigns that doubt the efficacy of vaccinations and immunizations (see Romania and Italy, the only two countries in Europe where cases of Measles are on the rise) and we have a scenario where the full risks and devastation from an outbreak will only be understood when it is too late.
As our cities get bigger, denser, and more common, so too will our risk of outbreaks - as well as the scale and scope. We need to be more critical in our understanding of how diseases spread - knowing that an ever-increasing demand for global travel will exacerbate the spread of contagion. We also need to understand that not every vaccine can be created and scaled as quickly as disease can spread. The importance of herd immunity - the epidemiological concept that the spread of disease is less likely when a sufficient proportion have been vaccinated or immunized - must be stressed and championed by global health and medical experts.
Exposing weaknesses in urban security
These urban blind spots represent real and tangible gaps in our global health security framework. As was the case with Zika virus, only a smattering of specialized experts were familiar with the virus and it only affected individuals in rural areas on a scant basis - but the virus spread to cities and made its way to other countries, as all viruses can do. As medical wards filled with thousands of infected patients and babies, the full risks and damage of the virus had been elucidated - and by then, it was too late.
There needs to be a great focus as a global community on reducing social exclusion and economic inequalities. Surveillance, monitoring and reporting of global diseases needs to be more efficient and streamlined. Involvement from additional stakeholders like private industry is essential. Technology and digital infrastructure need to fill the gaps that exist in our global health network - if we can stop the spread of disease, we must be able to at least limit it or slow it. Real-time data of outbreaks or sharp increases of diseases needs to be reported to national and international disease monitoring centers. We must stop seeing health through geopolitical a lens - poor health in other countries means that as a global community, we are failing - instead of the their problem, it is should be our problem.
As the global health community continues to grow, change and expand, so to do our approaches to urban security. These problems are immediate and are not going away - if we neglect to see urban security through the lens of health security, the next human pandemic will not be far away.