CORRESPONDENCE.

Waikato Times, Volume II, Issue 91, 28 November 1872, Page 2

CORRESPONDENCE.

To the Editor of the Waikato Times. Sir. —A letter upon re-vaccination in your issue of the 21st inst., leads to the conclusion that persons who have been once properly vaccinated are as susceptible of revaccination as those who have not been vaccinated at all. Experience has proved that the susceptibility to cowpox (vaccination), and liability to small-pox are identical, holding the closest relation the one to the other ; and as the former is but a modified and milder type of the latter 'disease, it follows, if the vaccinated and the unvaccinated are equally susceptible of the vaccine infection and to the same e::tent, that the former enjoy no advantage over the latter, and derive no special protection from small-pox under the first vaccination. ■Persons and children vaccinated for the first time, take the" infection completely and almost invariably. There are cases of total insusceptibility, but they are rare, and, happily, enjoy a corresponding immanity from small-pox. Those who have once undergone a successful vaccination, however, and are revaccinated under the most favorable circumstances, take the subsequent infection but very partially .indeed, and, in 50 per cent of the cases operated upon, fail to take the least effect beyond the merest irritation caused by the punctures made with the lancet. In about half of the cases submitting to revaccination, I have noted either that the cicatrices or marks of tlio original vaccination are very indistinct from age, or that the operation had been very imperfectly performed ; and, in these, revaccination is successful to a proportionate degree, but not to the extent of a primary vaccination. I have had large experience in this branch of my profession, botk in this colony and at home, having been a vaccinator under the Home Government several years, but I have not found climate in any way influence my experience on these particular points. Those who have been thoroughly vaccinated enjoy a protection from small-pox amounting to an almost absolute security for life; and in these, the vaccination scar or scars ought decidedly to cover not less than half a square inch, and would be, probably, better for reaching to three-quarters of a square inch. Now, the object of revaccination is to bring the infection in the constitution up to this standard of sufficiency where the first vaccination has been but imperfectly performed, or from any other cause only partially successful. Hence its desirability to those persons, and especially to those living in crowded cities, and others likely to travel much. 1 am encroaching upon your valuable space and apologise, but the subject is a very important one, I am, sir, yours, &c., B. C. Beau:, M.R.C.S.E,. L.S.A. Hamilton, 25th Nov., 1872.