May 1, 1888.] 



♦ KNOAATLEDGE ♦ 



155 



The evidence is not quite so clear in tbe case of vaccinia 

 and small-pox ; since it has not yet been demonstrated that 

 protection against a particular disease can only be given by 

 passing through a disease actually akin to it. It might be 

 argued that as the particuhxr effects of quinine which give 

 protection ;if:ainst malaria argue no kinship between malaria 

 and the action of quinine, so the protective influence of 

 vaccine inoculation does not necessaiily prove that the 

 germs which produce vaccinia (the disease, if so it can be 

 called, following vaccination), are the same in species as 

 those which produce small-pox. 



Still, in the light of recent evidence respecting zymotic 

 diseases and germ diseases generally, it m.ay be regarded as 

 practically certain that tlie disease germs of vaccinia are the 

 direct descendants of small-pox germs, which, during their 

 residence in the heifer have undergone a certain modification 

 rendering them innocuous ; while, nevertlieless, introduced 

 into the blood of the human body, they produce that par- 

 ticular change which results in what we call " protection " 

 against small-pox. This heing so, it may be regarded as 

 probable that in the case of any other disease known to be 

 produced by germs, methods of cultivation may be discovered 

 by which the disease germs may be so cultivated as to lose 

 their fatal power, while generating a disease sufficiently 

 akin to the more dangerous illness to render the patient 

 safe thereafter or for a while against its influence. So that, 

 as I pointed out several years since, when as yet such 

 expectations were regai-ded as fanciful, typhus, scarlet fever, 

 diphtheria, and a host of other ailments, which are known 

 to be due to the presence of living organisms in the blood or 

 tissues, may be treated as we now ti'eat small-pox. 



I may touch here on tlie ideas of that troublesome and foolLsh 

 class of per.sons who eill themselve.s " an ti- vaccinationists." 

 The strict action of the vaccination laws in England — a 

 country whose people have by no means been disciplined into 

 such strict obedience to Government control as continental 

 nations — has excited opposition, not only from persons who 

 recogni.se the mischief of undue interference with the people, 

 but also from those who are too ignorant to be aipable of 

 appreciating the evidence respecting the protective influence 

 of vaccination. A Herbert Spencer may reasonably object 

 to laws forcing the unwiser and emphatically least valu- 

 able portion of the population to protect themselves against 

 disease and death. But such objections to compulsory 

 vaccination are not to be confounded with the idiocies of 

 the Anti- Vaccination TiCague. Those who object to com- 

 pulsory vaccination qud compulsory, are among those who 

 recogni.se most clearly the protective influence of vaccination. 

 But inasmuch as this protection is open to all, and will 

 be taken advantage of by the most sensible, while the 

 spread of small-pox from the foolish sort who will not seek 

 this protection, can always be prevented by renewed vaccina- 

 tion among the rest, it is evident that compulsory vaccina- 

 tion tends to preserve the unwise opponents of vaccination — 

 a decidedly mi.schievous result considered in itself. The 

 very fulness of a man's appreciation of the value of vaccina- 

 tion as a protective against small-pox, may conceivably 

 lead to his objection to compul.sory vaccination. It by no 

 means follows that a man does not approve of a good thing 

 because he is unwilling that every one should be compelled 

 to partake of it ; often quite the contrary, in fact. 



It ought to be unnfce,<sary to cite evidence of the pro- 

 tective influence of vaccination, but I may here note two 

 cases which seem to me singularly striking : — 



1. Zurich Canton. Thelawof compulsory vaccination was 

 repealed in 188.3. Official returns recently published by 

 Professor Dunant, enable us to judge how many of the 

 more foolish sort (unfortunately, theii' babes for the most 

 part, but in such questions we must consider the class not 



the individuals) would have been preserved had the law 

 been left unchanged. The death rates from small-pox 

 between 1881 and April 1886, were as follows : — ■ 



Date. Deaths. 



1S81 7 



1882 



1883 . . 



1884 11 



1885 73 



First quarter of 1886 85 



2. In Germany vaccination is compulsory ; in France it 

 is not. Now, Dr. Ja,ssen points out among many other 

 striking examples of the efficacy of vaccination that during 

 the year 1885, in twenty-one towns in Germany, having an 

 aggregate population of 4,000,000, the deaths from small- 

 pox numbered twentj'-seven ; in fifteen French towns, 

 having the same aggregate population, the deaths from 

 small-pox amounted to 866. 



The significance of such results, which might be almost 

 indefinitely multiplied, will be recognised still more clearly 

 when we remember that deaths from small-pox are far from 

 being the worst results of an epidemic of the disease. 



It is noteworthy that men who seem careless about 

 applying the protective influence of vaccination to their own 

 families show a marked zeal in seizing at any protection for 

 tlieir cattle which kindred methods may provide. Tiius, 

 though Pasteur's researches into the terribly destructive 

 disease known as splenic fever (sometimes called anthrax or 

 charbon), were at first ridiculed and his conclusions opposed, 

 the proprietors of flocks and herds agreed with admirable 

 unanimity in accepting his means of protection as soon as 

 the validity of his system had been demonstrated. The 

 history of anthrax is instructive. The disea,se resembles the 

 black plague in its action and in the rapidity with which its 

 effects are developed. In bad cases death occurs in twenty- 

 four hours. Where the disease is very prevalent proprietors 

 have been ruined by the entire destruction of their flocks 

 and herds. Between the years 1867 and 1870 no less than 

 50,000 deaths occurred among horees, cattle, and sheep in 

 the district of Novgorod, in Russia, while 568 human beings 

 perished to whom the disease had been in various ways 

 communicated. 



Pasteur's inquiries into the development of anthrax were 

 characterised by the same combined patience, ingenuity, and 

 keenness which he had shown in his researches into pebrine, 

 the silkworm disease. So soon as he had recognised the 

 true nature of the anthrax bacillus he studied methods for 

 cultivating it so as to mitigate its poisonous effects. His 

 method consisted (or rather consists) in cultivating the 

 bacillus in meat-juice or chicken-broth, to which air has 

 access but not dust. A certain time is allowed to elapse 

 before it is employed for inoculation. If this period does 

 not exceed two months the virulence of the bacillus is little 

 diminished ; but if it is extended to three or four months, 

 the disease produced by inoculation is less severe and a 

 considerable proportion recover ; if the time is prolonged to 

 eight months the disease produced by the bacillus is so mild 

 that none of the inoculated animals perish, all quickly 

 regaining full health and vigour, while all are safe, for at 

 least a considerable period, from the deadly attacks of the 

 veritable anthi-ax. 



It was not until a crucial series of experiments (such as 

 cannot be made when human beings are in question) had 

 been carried out, that Piisteur's system of treatment was 

 adopted. A flock of fifty sheep was at his disposal. He 

 vaccinated (to use a convenient if not quite correct ex- 

 pression'! twenty-five of these with the cultivated anthrax 

 poison, repeating the operation a fortnight later. All the 

 animals thus treated passed through a slight illness, but at 

 the end of the month were as well as the remaining twenty- 



