Amazing history of maps and diseases
The idea that diseases have a spatial component and therefore can be mapped can be traced as far as the late 1600s. This period is the starting point for author Tom Koch, a clinical ethicist, gerontologist and professor, who was interested in the relationship between mapping and medical science. The motive behind his research that resulted in this book is that somehow, history seems to emphasize only one single historic example of medical mapping as the basis for its modern-day equivalent, obscuring a far more complicated (and turbulent) relationship between the two when examined in greater detail.
Although plague maps from the late 1600s form the earliest evidence of the relationship between mapping and medical science, the most well-known historical medical maps are those of John Snow, an English physician. His series of cholera maps of London in the mid-19th century showed a way of spatial thinking to help solve a medical problem (cholera outbreak), introducing the idea of a threshold population, a critical community-size above which the agent of a specific disease will thrive, and an epidemic can spread.
Although Snow´s work in the context of his day was insufficient, it led to a broader debate by contemporaries on the spread and origin of cholera, as well as how to improve Snow´s mapping approach. In hindsight, it turned out that the specific Snow case of the local outbreak of cholera in London in the 19th century and its accompanying topographic maps could be used as a model for medical science as a whole, laying a foundation for years to come.
The relationship between mapmaking and medical science since hasn´t always been a strong one. One reason for a divorce between the two is that breakthroughs in medical science such as the germ theory told local health officials where to look for causes for a specific illness, rather than using spatial and environmental analysis. Also, limits of reproduction technologies pervaded medical mapping through the early 20th century.
Interestingly, the maps reproduced in the book show that over time, the geographical scope changed from local to global. The notion that international port cities on international sea trade routes proved to be sources to where diseases “entered” a country, is illustrated by a series of case studies. But it is not until the 20th century that the question could be answered how local circumstances led to the outbreak of a disease. So-called “disease atlases” put disease outbreaks in a regional and global perspective, instead of local. It is during this time that medical geography and medical mapping were reborn as dynamic and probabilistic.
Although computer technology was used in the 1960s for medical mapping purposes, the technology was not there yet. And while “computer cartography” became more popular in the 1970s and the technology caught up with more readable and legible mapping, the users of the technology had to catch up as well, a process that would take two generations to realize. It is in the 1970s that statistics and medical mapping were wholly conjoined, as is illustrated with a few more case studies.
GIS enthusiasts will be happy to know that Koch devotes an entire chapter to GIS and medical mapping, where he states that the move from mainframe to desktop enabled to undertake research programs like those pioneered a decade earlier. Digital store of demographic and spatial data coincided with the evolution of GIS that became more web-centered. This process is ongoing and opens up new opportunities for medical mapping, which is illustrated by two new chapters on Ebola outbreak in 2013.
As the introduction of this book states, this is not just another cartography book. Instead, it focuses on how people over time came to use maps within the discipline of medical science. Koch describes very well how both mapping and medical science evolved over time and how one influenced the other, which makes a great read for everyone interested in mapping, medical science, and history.
A big comeback of location sharing. First Google and now Facebook. Who will be next?
Location-sharing is not a new idea. Remember Foursquare, Gowalla, and Google Latitude among others? Most of these services don’t exist anymore. The value proposition that they offered was clear, but the idea was a little bit ahead of its times and many people were not ready to challenge their privacy comfort zone. In the end, these services were too niche, with too small userbase to be a sustainable business.
In the meantime, our privacy boundaries have been slowly pushed to the next level. It seems that big players have noticed it and they decided to reintroduce location-sharing on a large scale. But this time they’ve learned their lesson, and they focus on making it useful and solving some real-life problems rather than do it for the sake of it.
Two weeks ago, Google announced a new feature that allows you to share your exact location in Google Maps for a given amount of time with your friends.
Last week Facebook revealed that it followed the same path and released a very similar feature on Messenger. Users can now share their real-time whereabouts with friends using ‘Live Location’ icon in the app. Clicking on it will allow users to broadcast their location for 60 seconds.
A similar feature has also been introduced in beta to Facebook-owned WhatsApp.
It is clear that sharing your whereabouts just for the sake of doing so, is not bringing any value to most of the users. But sharing your location in a controlled amount of time and only with people for whom this information is useful, makes a lot of sense. Since the information is not shared with the whole world or all your friends, most of the privacy issues are tackled.
With all these new features from Google, Facebook and others to come, location-sharing is definitely not cool anymore. But it is finally useful.