Conditions are similar in most countries of Europe, where, of course, the number of infected pigs is considerably smaller, but the disease depends less on this than on the way in which the pork is prepared.
Cases of trichinosis have been known to occur in nearly all the countries of Europe; further, in Egypt, Algeria, East Africa, Syria, India, Australia, and America. North Germany, more especially the Saxe-Thüringian states, is the classical land for epidemics of trichinosis; the mortality varies, but it may be very high.[306]
Prophylaxis.—The grave nature of the disease and the comparatively high mortality relating to trichinosis led the authorities to adopt certain preventive measures, which are the more necessary as national customs cannot be altered in a short time. As the usual process of pickling and smoking, even when long continued, does not certainly ensure the death of the Trichinellæ contained in the meat, and also because in roasting and boiling large pieces of pork a considerable time is necessary to permit the temperature required to kill off the parasites (62° to 70° C.) to penetrate to the middle of the joint, it appeared to be most practical to have all pigs microscopically examined for Trichinellæ before they, or parts of them, were placed on the market, and all infected meat condemned, no matter whether the Trichinellæ were present in large or small numbers, still undeveloped or calcified. Since 1877 obligatory examination of pork has been introduced in Prussia, though as yet it is not thoroughly carried out; other states of North Germany as well as the larger towns of South Germany soon followed; a complete army of trichina inspectors, officially examined and periodically controlled by experts, and whose number in Prussia amounted to 27,602 in 1896, this being even increased to 28,224 in 1899, have the charge of examining pork on certain lines laid down. These are at the present time uniformly administered. The proceeding is usually that the trichina inspector himself goes to the slaughterhouses, or special samplers take pieces of the muscles that are known to be the favourite seats of the parasite (pillars of the diaphragm, the costal part of the diaphragm, muscles of the tongue and larynx, intercostal and abdominal muscles); six small portions are separated from each piece, pressed between slides or special compressors, and carefully gone through by examining them with a low power of the microscope. The pigs free from Trichinellæ are passed for commerce; trichinous pigs, on the other hand, in Prussia, are only allowed to be used for industrial purposes, i.e., the hide and bristles are used, the fat is allowed to be melted down, or certain parts are used for the manufacture of soap or glue. In Saxony, however, it is still permitted to place trichinous flesh on the market, fully declaring its nature, and after having been heated to its deepest strata at a temperature of 100° C. in a suitable apparatus, and under the supervision of a veterinary surgeon.
As to the proportion of trichinous pigs to healthy ones, the following tables give the figures for Prussia:—
| Year | Number of pigs examined | Number of trichinous pigs | Proportion |
| 1878 | 2,524,105 | 1,222 | 1 : 2,065 |
| 1879 | 3,164,656 | 1,938 | 1 : 1,632 |
| 1881 | 3,118,780 | 1,695 | 1 : 1,839 |
| 1882 | 3,808,142 | 1,852 | 1 : 2,056 |
| 1883 | 4,248,767 | 2,199 | 1 : 1,932 |
| 1884 | 4,611,689 | 2,624 | 1 : 1,741 |
| 1885 | 4,421,208 | 2,387 | 1 : 1,852 |
| 1886 | 4,834,898 | 2,114 | 1 : 2,287 |
| 1887 | 5,486,416 | 2,776 | 1 : 1,988 |
| 1888 | 6,051,249 | 3,111 | 1 : 1,945 |
| 1889 | 5,500,678 | 3,026 | 1 : 1,818 |
| 1890 | 5,590,510 | 1,756 | 1 : 3,183 |
| 1891 | 6,550,182 | 2,187 | 1 : 2,996 |
| 1892 | 6,234,559 | 2,085 | 1 : 2,992 |
| 1896 | 8,759,490 | 1,877 | 1 : 4,666 |
| 1899 | 9,230,353 | 1,021 | 1 : 9,040 |
| 1902 | 9,093,210 | 725 | 1 : 12,397 |
The proportion, however, is not only subject to variation in separate years, but differs according to the district; thus, in 1884, in the state district of Minden there was one trichinous pig to 30,146 healthy animals, in Erfurt 1 to 14,563, in the district of Gnesen 1 to 101, in Schrimm 1 to 86, and in Schroda 1 to 68.
In Germany Trichinella is becoming LESS COMMON in pigs (Ostertag):—
(a) Prussia. | |||||
Year | Pigs found | ||||
| 1878–1885 | 0· | 061– | 0·048 | per cent. | |
| 1886–1892 | 0· | 033– | 0·043 | " | |
| 1896 | 0·021 | " | |||
| 1899 | 0·014 | " | |||
| 1902 | 0·011 | " | |||
(b) Saxony. | |||||
Year | Number of pigs | ||||
| 1891 | 0· | 014 | per cent. | ||
| 1892 | 0· | 011 | " | ||
| 1893 | 0· | 008 | " | ||
| 1894 | 0· | 007 | " | ||
| 1895 | 0· | 012 | " | ||
| 1896 | 0· | 0102 | " | ||
| 1899 | 0· | 004 | " | ||
| 1902 | 0· | 0056 | " | ||
(c) City of Berlin. | |||||
Year | Number of pigs | ||||
| 1883–1893 | 0· | 035– | 0·064 | per cent. | |
| 1893–1897 | 0· | 022– | 0·015 | " | |
| 1902 | 0· | 006 | " | ||
There is no doubt that the excellent preventive measure of official inspection for Trichinella has led to the avoidance of grave disasters; its introduction has not yet caused an entire cessation of trichinosis in man, because inspection of pork is not obligatory everywhere, so that human beings may become infected by unexamined trichinous pigs from their own country or from abroad, and also because an infection may occasionally escape notice. For these reasons the meat imported into Berlin from abroad as free from Trichinæ is examined again and not always in vain; finally, also, gross negligence may at times occur, or fatal errors may be made.