The Influence of Meteorological Conditions on the Yellow Fever Epidemic in Cádiz (Southern Spain) in 1800: A Historical Scientific Controversy

Abstract

A yellow fever epidemic occurred in Cádiz and other areas of southern Spain during the last months of 1800. An anonymous author attributed this disease to the contrast between the cold and rainy winter and spring, and the subsequent very hot summer. However, the physician J.M. Aréjula published a report in 1806 where he refuted this conclusion after a detailed analysis of the meteorological conditions in the area. This controversy is a good example of the discussion about the relationships between meteorological conditions and public health. In this work, this “scientific” controversy is studied. Although the arguments of both authors were inspired by the neo-Hippocratic medical paradigm, the anonymous author put forth a simple cause–effect hypothesis, while Aréjula recognized the complexity of the problem, introducing the concept of “concause” to explain the confluence of environmental and contagious effects.

Climate Change, Aquatic Ecosystems and Human Infectious Diseases in a Globalised World

“…In this Special Issue, our aim is to update the information related to the impact of climate change on human infectious diseases, especially those in which the vectors or parasites are related to aquatic ecosystems. This Special Issue, entitled "Impacts of Climate Change on Human Infectious Diseases related to Water Ecosystems", includes studies about infectious diseases such as vibriosis and water contamination by coliforms [1,2], yellow fever [3], malaria [4] and cholera [5]. These studies, which are related to different diseases caused by viruses [3], bacteria [1,2,5] and protozoa [4], are all focused on the aquatic environment.…”

“…This Special Issue, entitled "Impacts of Climate Change on Human Infectious Diseases related to Water Ecosystems", includes studies about infectious diseases such as vibriosis and water contamination by coliforms [1,2], yellow fever [3], malaria [4] and cholera [5]. These studies, which are related to different diseases caused by viruses [3], bacteria [1,2,5] and protozoa [4], are all focused on the aquatic environment. Many aquatic ecosystems play a role in the distribution of pathogens through rivers and sea currents [1,2,5], and eventually affect drinking water sources.…”

“…Furthermore, the rise in sea level, as well as extreme events-such as storms and hurricanes-can facilitate the contamination of drinking water in coastal areas [1] or near great lakes, favoring the proliferation of pathogens associated with water. The studies grouped in this Special Issue, although they were carried out in America [1], Asia [2] and Europe [3,4], provide, as a whole, a global perspective [5], as they provide worldwide representative case studies. Moreover, some of the diseases addressed in these studies are transmitted by vectors [3,4], while others are not [1,2,5].…”

“…Thus, Table 1 presents a synthesis of the main infectious diseases related to the aquatic environment that repeatedly appear in expert panels about climate change, highlighting the main climatic variables involved. The data were gathered from the studies included in this Special Issue [1][2][3][4][5] and from some reviews [9][10][11][12][13]. Table 1 is not a thorough compilation of these infectious diseases related to aquatic ecosystems; it rather provides a general view of those which are gathered in different reports and expert panels.…”

“…This would be the case of Aedes aegypti and Anopheles atroparvus, as vectors that transmit yellow fever and malaria, respectively. In this sense, [3] analyzed the controversy around the climate causes of a yellow fever epidemic in the early 19th century in Southern Spain. This study shows that the climate conditions of Southern Spain in the year 1800 (humid winter and spring, warm summer) were adequate for the mosquito species Aedes aegypti and the epidemic outbreak.…”