HEALTH NOTES

Evening Post, Volume CIV, Issue 74, 24 September 1927, Page 17

HEALTH NOTES

VACCINATION

PREVENTION OF SMALLPOX

(Contributed X>y the Department or Health.)

Ko disease has pursued the human race with such persistence and malignancy as smallpox. The disease was brought to .Western peoples from the East at the beginning of the Middle Ages. It had been indigenous in India from very ancient times, a special divinity being recognised- for the disease. Long before the beginning of our history China repeatedly had extensive epidemics and practised, as a protective measure, inoculation from the pock of a case, sometimes applied dry to the nose as a snuff. Up to Jcnner's time smallpox was the most common and most deadly of all epidemic diseases. No remedy was of use against it.

About 150 years ago the comeliness of English milkmaids was a striking feature. Practically they alone were free from the blemishes of smallpox. Cowpox (or vaccinia) was at that time very prevalent among cows. Scratches on the hands of the milkers became infected from the pustules on the udders and teats. The hands developed similar lesions, aecompnaied by some fever and enlarged glands in the armpit. People so inoculated were protected from smallpox; hence the comeliness of milkmaids among a population where only five persons out of a hundred escaped the disease.

Edward Jenner in 1796 turned these facts to practical use, transferring to a boy's arm cowpox matter from the hand of a dairymaid. She had, scratched her hand and become infected from her master's cows. A typical vaccination take occurred. In the months that followed, the boy was twice inoculated with smallpox matter taken from a pustule, but no disease followed. By this and further experiments cowpox was seen to be a local and mild disease in man, easily transferred from man to man giving protection against smallpox.

Nowadays it has been practically settled by animal experiment that cowpox and smallpox are one and the same disease, smallpox virus beng so altered and modified, by its transmission through the cow that it has lost its virulence for man. This altered bovine form (vaccinia or cowpox) on inoculation £nto man results in the few pustules which we know as "vaccination," but also affords a high degree of protection against subsequent attacks of smallpox. Cowpox is smallpox modified by transmission through cows or calves, losing its infective but retaining its immunising power aganist smallpox. It protects against both severe smallpox or the mild form known as alastrim.

USE OF LYMPH.

Jenner's arm to arm method of vaccination is no longer practised, but vaccine lymph is prepared by the inoculation of healthy calves. The pustule contents are collected and "purified with glycerine, the lymph thus prepared being stored in. glass tubes till used. This bovino lymph eliminates the danger of person to person. All lymph used in New Zealand is supplied by the Government, and taken from a healthy heifer. The method of vaccination is a simple one, a scratch being made through a drop of vaccine lymph placed on the previously sterilised skin. Care has to be taken to do this in an aseptic manner. About the fourth day inflamed spots appear at the inoculation site, becoming pustules by the eighth day. About the twelfth day these dry, leaving a scab which finally drops off about the twentieth day. Slight constitutional disturbance accompanies the development of the vesicles. There may be three days' fever and enlarged glands in some cases. If desired, vaccination can be as readily performed on the leg as on the arm. Wherever carried out it prevents all forms of smallpox, it produces but slight discomfort, while its risks are negligible. DURATION OF IMMUNITY. Vaccination of infants is attended with less general reaction and fewer complications than vaccination of older children. It is best done as soon after birth as practicable, preferably before teething. The "take" is mild usually, and the scar fades more completely than sears of primary vaccinations performed later. The protection afforded is lost by different individuals at different rates. Some need to be vaccinated more often than once in five years to maintain full protection; others may be vaccinated less frequently than once in twenty years, and still maintain high immunity. A primary vaccination-in infancy, followed by a successful re-vaccina-tion at the tenth year or sooner, will as a rule protect throughout life from mild smallpox. Should there be any danger of severe smallpox, all persons who have not been successfully vaccinated within one year should be vaccinated again. SUCCESS OF VACCINATION. Since the discovery of vaccination, the ravages of smallpox, the historic scourge of man for centuries, have been curtailed to a remarkable degree. It could be practically eliminated if vaccination were universal. In communities where vaccination in infancy, revaccination at school age, and perhaps again in adult life", is practised there is little smallpox. In Germany, where 60,000,000 people are surrounded on three sides by badly vaccinated countries, smallpox has been almost stamped out. Smallpox was formerly a disease of children, but since vaccination protects the child, adults are being more and more, affected. This is due to neglect of re-vaccination. Where vacciha-' tion is not practised, children still suffer most, the disease being very fatal in the first two years of life. The vaccinated children are passed by, but the unvaccinated living in the same house are attacked, when epidemics appear. Unvaceinated children have over j twenty times more chances of a fatal i result than their playmates who can boast the protective sear.VACCINATION IN NEW ZEALAND. Year by year vaccination is being neglected in our' country. A baby weighed recently was seen to have a vaccination pustule. "O! Why did you have that done," remarks a mother, "Nobody bothers these days." This is just the trouble; people are not "bothering." Slowly, but surety, a large unprotected population is gathering. Experience shows that smallpox may occur any time where the majority of people are unvaceinated. Sooner or later an epidemic will appear, in spite of careful quarantine precautions. For many years now England has been neglecting to enforce vaccination, and allowing vast numbers to avoid complying with her law of compulsion. The majority of English people are now unvaecinated, and the country is suffering for its indifference. In England there has been an increasing incidence, of the disease, mostly mild in character, sometimes severe, and occasionally fatal, but always inflictingpain, suffering, and loss which is preventable, and ought to be prevented. As the unvaecinated population has grown, so has the prevalence of the disease increased, as the following figures show:—lo22, 973 cases; 1923, 2-500 cases; 1924, 3800 cases; 1925. 5300 cases; 1926, 10,100 cases. Almost'without ex-