The legal question as to whether revaccination has been successful or not can not accurately be answered, owing to the great variation in revaccines. Thus the statistics of different observers vary greatly. A positive reaction in the sense of a pathological process follows almost. each revaccination. The question should be: Has revaccination afforded a renewed protection? When on the day of inspection no reaction is seen, the vaccination may not have taken at all, or the immunity was still so great that it produced a premature reaction. Renewed protection can only then be expected when revaccination is followed by the forma tion of a distinct vesicle, so that at the time of inspection there is seen a pustule or a scab, surrounded by a reddened or pigmented border.
Fever does not occur with premature reaction. With accelerated reaction, it is usually but slight and transient. Subjective symptoms consist in itching and pain in the wound, which seems greater than among the first vaccinated, because the revaccinated are capable of expressing their discomfort.
In my experience, accessory pocks and general eruption never occurred with revaccination, but swelling of the lymph-glands and pain occur among the revaccinated adults more frequently than among children vaccinated for the first time. Whether this is dependent. on the effect of vaccine or other conditions, is not well understood.
Complications of formation of accessory pocks in the areola and cow-pox exanthem about the tenth to the fourteenth day can not be regarded as complications, but are really a part of the process. Complications are vaccinal infections of the individual from himself or from his surroundings; also secondary infection caused by the lymph or carried into the wound later. By far the most frequent complication is caused by the children wiping off the lymph, which is usually found around the area of vaccination, with their fingers and inoculating other parts of the body. At each of these places, there develops a regular vaccinia, passMg through the same stages of growth as the one on the arm. These auto-inoculations occur frequently in places where there are abrasions, caused by eczema or pruritus from other causes, especially on the vulva, hands and face. We call this form, according to Riether, raccinosis. It differs from the vaccine exanthem in its localization, character and time of appearance. The exanthem appears simultaneously over the entire body, and in places which the hand can not reach, vaccinosis only in places with which the hands can come in contact. The exanthem is mostly papular, pock-like formations
are rare. Vaccinosis forms typical pustules. The exanthem appears in the fourth period, vaccinosis in the second or, at the latest, the third period. The best prophylaxis against vaccinosis consists in watching the children until the wound is dressed, and a few hours after vaccina tion washing the skin carefully.
Auto-vaccination may occur in the second period by carrying the contents of an open vesicle to other parts. The new foci resemble second ary vaccinations, but do not become very large because their develop ment is arrested at the beginning of the fourth period. Because of this auto-vaccination, we do not vaccinate children with eczema and lichen urtieatus. When vaccination becomes necessary because of danger of smallpox, the child's arm must be carefully watched and not left without a sleeve. It may even become necessary to bandage the hands, or by applying a cuff over the elbow, to prevent flexion of the forearm.
A broken vesicle is less dangerous to the child than to his associates. Most cases of severe vaccine infections arise among children of the same family who have not been vaccinated, or among adults who have been vaccinated a long time previously, by playing with a vaccinated child and thus carrying the material to the eyelids, nose, areas of eczema, etc.
Unvaccinated children should therefore be kept separate from the children at the height of vaccinia.
Complications caused by pathogenic bacteria contained in the lymph are extremely rare. In the earlier clays when the arm-to-arm method of vaccination was in vogue it occasionally occurred that syphilis was trans ferred. After the vaccinia there appeared a regular primary syphilitic lesion at the site of vaccination. This danger, as well as that of trans mission of erysipelas, pemphigus, furunculosis, and septic processes, is now avoided by the use of animal lymph. Secondary infection of the pustule by scratching with dirty fingers does, of course, occur, resulting most commonly in suppuration, and causing prolonged duration and a hard infiltration of the sore. Erysipelas may also follow. A diagnosis can only be made when the pustule is broken and after the disappearance of the areola. There reappears a sharply outlined infiltrated redness at the site of vaccination and there is temperature. Many supposed eases of erysipelas are, in reality, only very prominent areolas.