I hope you are all safe and well. I have been discussing covid-19 maps with
fellow geographers around the state, and we believe we've identified an
important problem. Nearly all of the maps we have seen show only the number
of confirmed covid-19 cases. In spite of the fact that public health
officials consistently say that these numbers represent only some of the
cases and that the virus has likely already made its way into every county
in Maine, we have heard many people, one-on-one and on social media, say
that the virus is "not in my county" as an excuse for not practicing social
distancing. Maps showing confirmed cases are probably part of the problem.
The folly of the "not-in-my-county" excuse was driven home for me over the
last couple of weeks when my own 23 year old kid and their roommate came
down with apparent cases of covid-19 in Portland. They were diagnosed by
their doctors via telemedicine and never tested because they lacked other
risk factors. Since this is currently the practice, clearly the number of
actual cases is much, much larger than the number of confirmed cases, and
the potential for spread across the state is much greater than confirmed
case numbers would indicate. Both are recovering and are in quarantine at
home, thank goodness.
From past studies on how people use and derive meaning from maps, we know
that people often skip written information and derive a simplified message
from a map or other such easily digested visualization. The maps of
confirmed cases that are so common in the press and social media are likely
no exception, so we believe many people are glancing at these maps and
drawing erroneous conclusions. *The geographers I have spoken with have
agreed to begin including high-profile disclaimers in their maps to
indicate that the number of actual cases is likely much larger and the
virus is likely much more widespread than the number of confirmed cases
would indicate. I'm writing to urge anyone creating such maps to do the
Currently, the state's official case count page
includes the following disclaimer, however, it is in plain text and
separate from the map: "This is likely an underrepresentation of the true
number of cases in Maine since not all individuals are being tested. For
individuals not considered to be at high risk, medical providers are
currently advised to diagnose COVID-19 based on symptoms." So, it is likely
that many people go to that page and glance at the map without reading the
disclaimer. I have written to the CDC to recommend that they raise the
profile of the disclaimer and place it on the map itself.
I gather from what I have read that there is no way without more widespread
and targeted testing to estimate the actual number of cases around the
state (or anywhere else in the country). So, I understand that the number
of confirmed cases is the only quantitative information available to
report. Perhaps we can all work on improving the way this information is
transmitted to the public with more careful map design.
I hope you find this information helpful.
Tora Johnson, PhD (she/ her)
Chair, Division of Environmental & Biological Sciences, Science Hall 107a
Director of GIS/ Associate Professor, GIS Lab & Service Center, Torrey Hall
University of Maine at Machias
[log in to unmask] ~ (207) 255-1214 ~ Twitter: @toradignity
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