Historical Thematic Map - Cholera Epidemic in the State of Ceará, Brazil, in 1862.

Barão de Studart

Estação Ferroviária de Maranguape - Século XIX

In 1904, Dr. Guilherme de Studart, also known as Baron of Studart, a medical doctor and scholar in the State of Ceará, Brazil, presented to the 4th Latin American Medical Conference, held in Rio de Janeiro, a report on the climatology, epidemics, and endemics in the 19th century in his State. Later, in 1909, Dr. Studart’s report was published in the city of Fortaleza (Capital of the State of Ceará) as a book entitled Climatologia, Epidemias e Endemias do Ceará (Climatology, Epidemics and Endemics of Ceará).

We can use the table that Dr. Studart presented in his book, on page 57, with the number of people, a total of 11,000, who died during the cholera epidemic of 1862 in each township in the State of Ceará, to construct a historical thematic map. The geographic units to construct a thematic map, using Dr. Studart’s table, would be the townships and the base map would be the State of Ceará. We can construct a graduated symbol map to show the number of deaths for each township. Graduated symbol maps use symbols of varying sizes placed within a region (in this case the townships of Ceará) to denote the value ascribed to it. We would use a circle to symbolize the number of deaths, not a skull, even though a symbol that relates to the theme of the map is often complementary and adds to its effectiveness. If Dr. Studart had provided the number of inhabitants for each township in the year 1862, we would be able to make a choropleth map showing the mortality rate by a specific number of inhabitants.

Even though the data cannot answer any question concerning the location most affected by the disease because we do not have available the number of inhabitants per township, a graduated symbol map of the number of deaths can tell more than just a simple table like the one Dr. Studart presented in his book in 1909. A map, like any other picture, can, in many cases, be more effective than a table of data. Even though this map would not answer many historical questions, a thematic map of the number of people who died of cholera in each township of Ceará during the 1862 epidemic can actually raise questions for further research. One can ask, for instance, why so many people died in the township of Maranguape, and then try to find out if the mortality rate there was really higher than in the other townships. If, indeed, the mortality rate in Maranguape was much higher than in the other townships, one can then ask why. Also, it is known in the folk culture of Maranguape that Saint Sebastian intervened in ending Cholera there in 1862. Once we know the mortality rate there, we will be better able to understand, for instance, why the people of Maranguape had to resort to San Sebastian’s intervention to end the epidemic.

Neda Bezerra