According to Benjafield, the pandemic first commenced in the Egyptian Expeditionary Force in May, 1918, but the maximum incidence was not reached until September and October. The cases during the earlier period of the epidemic were on the whole mild in type and of short duration, only a very small proportion being complicated by bronchopneumonia. The epidemic continued from November, through February, 1919, but the number of cases showed a marked decrease during the last two months.
The month of June saw the spread into England which we have already described, and the continuation from the German West front back into the enemy territory.
Rose reports that on the 3d of June, 1918, in Strasbourg the first cases of influenza were reported in his hospital and that by the 15th of the month the disease was practically epidemic. Wachter in reporting cases from Frankfurt a. M. says that the cases of influenza in that city appeared from the beginning of June, 1918. Schmorl remarks that influenza became epidemic in Dresden in the beginning of July, 1918. According to Koepchen, the disease was epidemic in Bonn the 25th of June.
An editorial comment in the Deutsche medizinische Wochenschrift, July 4, 1918, remarks that the influenza pandemic “which probably has spread from Spain in the last few days” has appeared in several places in Germany in the South and the North, and in Berlin. According to the information received up to that time the disease was of short duration and without severe complications. The issue of July 11th reports that the influenza epidemic appears to have already passed its peak in Berlin and that in Süddeutschland the spread of the epidemic has become very wide.
The Office International d’Hygiène Publique records that the pandemic spread throughout Switzerland towards the end of June, 1918, after having invaded a certain number of European states, coming from various army fronts. It was at first of mild severity.
Böhm states that the deaths from pneumonia and influenza in Vienna began to show an increase in the week ending July 30th. In August they returned to the normal rate. The second wave occurred in Vienna in the middle of September.
From the information at our disposal we are unable to determine from what direction the pandemic entered either Switzerland or Austria. The point of entry into Switzerland is of relatively little importance in tracing the spread on the continent of Europe. Presumably it entered from the north or northwest. The disease appeared in Berne in June, reaching its height in that canton in the middle of July and dying out in August (Sobernheim and Novkaovie).
Information of the place of entrance into Spain is also rather indefinite. We are told that Barcelona was one of the cities attacked early. Barcelona is situated on the Mediterranean near the French border and is quite directly connected by commerce with Marseilles and other French ports on the Mediterranean.
In June the disease had also spread to Norway and outside of Europe to the West Indies, South America, India and China. A short notice in the Public Health Reports tells us that epidemic influenza with an estimated number of 1,500 cases began in Christiania, Norway, about June 15th.
Atiles relates that influenza appeared in Porto Rico in June, soon after the arrival of a ship from Spain. It spread rapidly, and it is estimated that at one time fully eight per cent. of the entire population had the disease simultaneously, and that forty per cent. of the population were affected during the epidemic.