Page:Encyclopædia Britannica, Ninth Edition, v. 15.djvu/338

Rh 318 exposure to malaria-; they occur (not exclusively) in those who have had fever and ague ; they are sometimes accom panied by suggestions of the cold, and hot, and sweating stages of the true paroxysm ; and they often yield to the great anti-malarial remedy, quinine. Such patients have the general ill-health and suffering, as well as the pallor, of the malarial cachexia. The morbid anatomy of malarial fevers is chiefly confined to congestions and enlargements (with textural changes) of the spleen and liver. One of the most salient patho logical facts is the occurrence of black pigment in the blood, and deposits of it in the spleen, liver, and other parts. The malarial process sometimes leads to ulcera- tions and sloughing of the mucous membrane of the great intestine, not distinguishable from those of dysentery. The malarial fever of Rome is often associated with more or less of swelling and, it may be, even ulceration of the lymphatic follicles of the small intestine, as in typhoid fever ; the same anatomical condition was associated with much of the malarial fever of the American Civil War (typho-malaria). Geographical Distribution and Prevalence. Malaria has been estimated to produce one-half of the entire mortality of the human race ; and, inasmuch as it is the most frequent cause of sickness and death in those parts of the globe that are most densely populated, the estimate may be taken as at least rhetorically correct. In the British Islands, sporadic cases of ague may occur anywhere ; but malaria is not now endemic except in a few localities, among which may be mentioned certain parishes on the Essex side of the Thames estuary. In France there are several districts that are still notoriously malarious. In the interior these are chiefly found in the valley of the Loire (Sologne) and of its tributary the Indre (Brenne), and also in the valley of the Rhone, more particularly near the confluence of the Saone (Dombes, Bresse). France has two great coast regions of malaria, the one on the Atlantic seaboard, from the estuary of the Loire to the Pyrenees, with especial intensity in the Charente, and the other on the Mediterranean coast, from the Pyrenees to the Rhone delta. The most con siderable malarious district of Switzerland is in the Rhone valley from Sion to the Lake of Geneva. In Germany, the upper valley of the Rhine and the sources of the Danube have a certain character for malaria ; but it is chiefly on the western seaboard of Schleswig-Holstein and in the moors and marshes of Oldenburg, Hanover, and Westphalia that the disease is endemic. Scarcely any province of Holland can be said to be quite free from it, while Grb ningen, Friesland, and Zealand (with brackish marshes) are the most unhealthy. The .parts of Belgium that are almost or altogether exempt are the high-lying districts of Brabant, Namur, and Li6ge. In Sweden, malaria is endemic in the central depression of the country (especially on the shores of Lake Wener), and it has of late years spread northwards in epidemic outbreaks. For the countries of southern and eastern Europe (Spain and Portugal, Italy, Hungary and other Danubian states, Turkey, Greece, southern Russia), the language used to describe the prevalence of malaria has to be pitched in a somewhat higher key. There are certain pestilential districts of those countries where almost the half of the population suffers from ague, and there are even limited areas which are too malarious to be inhabited. The lower basin of the Danube (from above Vienna to the Black Sea), and the basin of its tributary the Theiss, are in the first rank. Both sides of the Adriatic have malarious localities, the chief being the delta of the Po and the Gulf of Com- accio ; among other unhealthy parts of Italy are the strip of coast from Pisa to Civita Vecchia (Maremma), the Roman Campagna, the Pontine Marshes, the neighbourhood of Capua, and the Neapolitan and Calabrian coasts. Sicily is highly malarious, both in the plains and in the higher districts ; and that is equally the character of Sardinia, Corsica, and the Balearic Isles. Greece, the Ionian Islands, and Crete take a high place among European malarious countries ; there are also numerous unhealthy localities on the shores of the Caspian and Black Seas and in Asia Minor. For countries in both hemispheres situated between 35 N. and 20 S., to describe the prevalence of malaria in detail would be practically to give the whole geography within those lati tudes. The regions of special intensity are the west coast of Africa, the American seaboard (with the West Indies) from the Gulf of Mexico to Pernambuco, parts of India (the Terai, the Doab, the Sunderbunds), parts of Sumatra, of Java, and of Borneo. Gibraltar, Malta, Aden, Singa pore, and Manila enjoy a comparative immunity from fever ; the healthiest islands of the West Indies are Barbados, St Vincent, and Antigua. In England, the fen district of the eastern counties, Romney Marsh in Kent, and the marsh district of Somer set have in great part ceased to be malarious within recent memory; and there has been a proportionate improvement, through drainage, in most parts of Holland, in some of the malarious districts of France and Italy, and in Algiers. Portsmouth in England and Rochefort in France are examples of towns that have entirely lost their evil repute for malaria ; and there are many towns in the United States, as well as in the East, which are much less malarious than they used to be. Wherever malarial fevers have become less frequent, they have also become milder in type. On the other hand, malaria has become intense where it was formerly unimportant or altogether unknown. It is incredible that the Roman Campagna could have been so malarious at the time of the empire as it is now ; places on the coast, such as Ostia and Palo (Alsium), which are now almost uninhabitable in summer, were then the favourite summer resorts of the rich ; while the Campagna, which is now almost entirely given up to pasturage, was not only densely populated, but was even specially com mended as salubrious. In North Africa, Asia Minor, and the East, malaria has taken possession of the ruined sites of ancient cities, and of large tracts of land that must have been at one time highly cultivated, but are now treeless, barren, and sometimes marshy. Of recent years malaria has appeared in Reunion and Mauritius, and it has reappeared in Connecticut ; in the two islands the associated circumstances are somewhat complicated, but they relate to changes in the cultivated area. The re appearance of ague in New England and the recent appearance of a form of masked ague in New York and elsewhere are at present unaccounted for. Earthquakes were said by older writers to have brought malaria to a locality ; a recent and well-authenticated instance is that of Amboyna in the Moluccas, which has become strikingly un healthy since the earthquakes that occurred in it in 1835. Among the numerous military enterprises into whose records malaria enters largely, may be mentioned the expedition against Carthagena (1741), the Walcheren expedition (1810), and the capture of Rangoon (1824). Recent enterprises in which malarial fever has been a great factor are the expedition against Achin by the Dutch (1873), the occupation of Cyprus by the English (1878), and the subjugation of Tunis by the French (1881). Schemes of colonization, such as the Darien scheme (1701), have sometimes been frustrated by malaria. Of historical personages, James I. and Cromwell died in London of malarial fever, the latter of a pernicious tertian. There have been numerous historical epidemics of inter-