ERUPTIVE FEVERS - This class includes in our table of diseases four distinct forms: 1, measles ; 2, scarlatina ; 3, varioloid eruptions ; 4, erysipelas.
There may be much difficulty in deciding whether a case pre senting itself with the general characters of fever, may not termi nate in some cutaneous eruption.
The probability is to be learned from the chances of exposure to infection, and also, in some measure, from the suddenness of the attack. "The appearance of the eruption soon determines the point, and often has shown itself ,before the amount of febrile dis turbance has been such as to call for medical aid. It is of im portance to avoid mistakes in such matters, because an early isola tion of the sufferer may prevent the spread of the malady to other members of the family, and blame, greatly disproportioned to the extent of the oversight, is always awarded to the attendant who has not foreseen the possibility of the occurrence.
In case of a sudden attack, the age of the patient has some bearing on the possibility of eruptive fever, because so large a proportion of these cases occur in early life. Inquiry ought to be made whether the patient has previously suffered from measles or scarlatina, or is protected from smallpox by vaccination.
Children suffer more frequently from most of these fevers than adults. An attack of measles is rare after puberty, because so few persons pass through the period of childhood without suffering from this disorder, and its recurrence is not a common event. The liability to scarlatina seems to be very greatly diminished in adult age. Unvaccinated children are especially liable to small pox, if at all exposed to its contagion ; after vaccination, the liability spin increases as age advances, from twelve or fifteen up to twenty-five or thirty. Both in the modified and unmodified forms, a first attack of smallpox may occur at any period of life, but is very much less common after the age of thirty. Second attacks of all these diseases are unusual, but exceptions are sometimes met with. Erysipelas, on the other band, is not a disease of child
hood, and does not in any way guard the system against a second attack.
The period of the illness, when the case is first seen, greatly aids in determining whether it may be one of eruptive fever or not ; for, after three or four days, the chances of scarlatina or smallpox are almost gone—the eruption of measles is sometimes deferred to the sixth day of the fever ; but these are the extremes, as the eruption is generally seen earlier. Definite rules are laid down in books ; but these will be found in practice to be very frequently deviated from, if the history given by the friends or the patient himself be true.
In the preliminary stage, the general symptoms are such as indicate a more s.ctive or sthenic type of fever than those which are not attended with cutaneous eruption : the skin is hot, and the pulse firm, and there is less of lassitude and depression. Cases of simple continued fever sometimes present similar symptoms in the early stage, and this may be accompanied by some general redness of the skin which is then apt to be regarded as the pre cursor of eruptive fever ; it is, so far as we know, only accidental, and the progress of the c,ase can alone determine,its nature. On the other hand, in some of the very worst forms of sc,arlet fever, the general symptoms put on a typhoid type ; and then the cuta neous eruption is scanty, or may be even altogether absent ; the depression is great, and the whole system seems overpowered by the poison. Less frequently, an analogous condition is met with in smallpox, with this difference, that the cutaneous eruption is excessive in the early stage, but the constitution of the patient has not power fully to develop it ; when antecedent blood-disease leads in such c,ases to the formation of petechim, the diagnosis is very' obscure. Suppression of measles seems to have more to do with the coexistence of internal inflammation than with the power of the miasmatic poison.