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FUTURE OF PREVENTIVE INOCULATIONS
758 to 49 years and decreases rapidly until 70. Accordingly the mortality in women is 143% of the estimated mortality, and in men 288%, or more than double the normal. Bechgaard postulates a sex difference which causes the circulatory system to be more resistant to raised blood-pressure in women. The prognosis becomes worse with increasing age owing to associated myocardial degeneration, and it is bad in malignant hypertension. Although Bechgaard’s material consists of patients who had a blood-pressure of 160/100 mm. Hg, or a systolic blood-pressure of 180 mm. Hg at the first examination, he defines the upper limits of normal blood-pressure as 140/90 mm. " in agreement with most of the recent investigations." Accordingly, he regards people who have a blood-pressure of more than 140/90 mm. as hypertonics, even if they are over 40 years of age. He adds, correctly, that " with this limit a very large number of older people (in case of the oldest more than 50%) are regarded as hypertonics." This would not be accepted by British and American observers, who regard as abnormal in people over 50 a blood-pressure of 170/105 mm. Hg taken under proper precautions on at least three occasions.8 DETERMINING THE TIME
OF
OVULATION
of cases of infertility it is often The ascertain the time of ovulation. methods used for this purpose include examination of the vaginal smear and the cervical mucous plug, biopsy of the endometrium, and, more recently, charting of the should show a slight temperature, which theoretically fall at the time of ovulation.99 Unfortunately this last method, which has the attraction of simplicity, does not seem to be proving as accurate as was hoped. Farris of Philadelphia, proposes another way of establishing the time of ovulation. He finds that if the patient’s urine is injected into an immature white rat, the rat’s ovaries become hypersemic if ovulation is taking place, but not otherwise. The first morning specimen of urine is used, and 2 ml. is injected subcutaneously into each of two animals. The animals are coal-gassed after two hours and the abdomens opened. The degree of redness of the ovaries is compared with a standard colour chart. Farris attributes the hyperaemia to the action of pituitary gonadotrophin, which shows a peak rise at the time of ovulation. This new test is certainly of scientific interest, and should prove valuable in laboratories equipped to perform it. The reading of the reaction, however, is by no means easy, and Farris admits that abnormal reactions are fairly common. We still await the simple, cheap, . reliable, easily interpreted test for ovulation which gynaecologists would find so useful. IN the
important
investigation to
FUTURE OF PREVENTIVE
INOCULATIONS
THE list of diseases for which satisfactory preventive inoculations have been discovered is ever lengthening. Dr. H. J. Parish, in his presidential address to the epidemiological section of the Royal Society of Medicine on May 23, reviewed current immunological procedures for each disease in turn. In the prophylaxis of diphtheria and tetanus, typhoid and typhus, smallpox and rabies, yellow fever and cholera, the use of an appropriate vaccine or toxoid is universally practised. Evidence of the value of pertussis vaccine is still somewhat contradictory, and the short-lived immunity obtained from influenza vaccine at present limits its application. Promising preliminary reports are appearing on the use of an attenuated mumps virus, and an effective attenuated 8. Evans, W. Lecture to the Association of Industrial Medical Officers in London on June 19, 1946. Barton, M., Wiesner, B. P. Lancet, 1945, ii, 663; Halbrecht, I. Ibid, p. 668 ; Nieburgs, H. E. Ibid, 1946, i, 627. 10. Farris, E. J. Amer. J. Obstet. Gynec. 1947, 52, 14. 9.
measles virus may in time be produced. Dr. Parish believes that advances depend on close cooperation between the immunologist, the bacteriologist, and the chemist. Many unsolved problems remain to be tackled. Knowledge of the basis of racial and species immunity
(inherent non-susceptibility) is entirely lacking. There is explanation of the immunity of man to avian tuberculosis or of dogs and goats to tetanus. Again, we know that immunisation of the pregnant mother with diphtheria prophylactic raises the circulating antibody titre of the child, but although passive immunity can be conferred on the mother by injection of diphtheria no
antitoxin in horse serum, these immune bodies do not Most exotoxins can be pass the placental barrier. measured quantitatively and qualitatively, and they are relatively stable substances ; but endotoxins are in a different category and our present understanding of their action is much less complete. Dr. Parish suggested that in the near future much effort will be expended on elucidating the antigenic structure of organisms and preparing pure stable antigens capable of exact measurement and less likely to produce allergic manifestations. Other paths of research are the use of new mineral salts to combine with antigens-such as the aluminiumphosphate diphtheria toxoid of Holt-and careful assessment of the antigenic potency of strains used in the preparation of vaccines and toxoids. The work of Barr and Glenny,l showing that higher antibody titres can be obtained with two doses of A.P.T. at a threemonthly interval (instead of the usual one month) reminds one that we do not yet know the optimum spacing or dosage of diphtheria toxoid. There is little hope, in Dr. Parish’s view, that artificial immunity will be obtained without recourse to parenteral injections, and the ideal of all antigens being administered in one single inoculation is far in the future. The growing practice, however, of combining certain antigens (e.g., diphtheria and tetanus toxoids with pertussis vaccine) should, he thought, become more common, for it reduces the number of injections without apparently reducing the immunising value of each antigen. OUT OF POCKET ENGLISH local government has a fine record of unpaid service. Those taking part have given generously of their leisure and energy, and in the past they have not grudged the expenses that went with their duties, for they were usually in a position to afford them. Today, however, with altered social and economic conditions many of those best fitted to serve on local councils can only do so at a sacrifice which we are beginning to feel it is unfair to ask them to undertake. The interdepartmental committee which have just reported2 to the Ministry of Health and the Scottish Home Department on the expenses of members of local authorities confirm these uneasy fears. From the evidence they received they gained the impression that some members were suffering undue hardship, and that suitable candidates were being deterred from standing for election by fear of expense and loss of time. They have therefore recommended that local authorities should have power to pay allowances to councillors who lose remunerative time in attending meetings and carrying out their public duties, and that councillors should be entitled to be paid travelling expenses and subsistence allowances. The principle involved is of importance to the new health service, which will depend so much on the wisdom and generosity of those who sit on its committees and boards. If we are to have practical members chosen from among working people-whatever their work _may be—it is important that no-one should be hindered from accepting office from fear of out-of-pocket expenses. J. Hyg. Comb. 1945, 44, 135. 1. Barr, M., Glenny, A. T. H.M. Stationery Office. Pp. 51. 1s. 2. Cmd. 7126.
OF
OVULATION
of cases of infertility it is often The ascertain the time of ovulation. methods used for this purpose include examination of the vaginal smear and the cervical mucous plug, biopsy of the endometrium, and, more recently, charting of the should show a slight temperature, which theoretically fall at the time of ovulation.99 Unfortunately this last method, which has the attraction of simplicity, does not seem to be proving as accurate as was hoped. Farris of Philadelphia, proposes another way of establishing the time of ovulation. He finds that if the patient’s urine is injected into an immature white rat, the rat’s ovaries become hypersemic if ovulation is taking place, but not otherwise. The first morning specimen of urine is used, and 2 ml. is injected subcutaneously into each of two animals. The animals are coal-gassed after two hours and the abdomens opened. The degree of redness of the ovaries is compared with a standard colour chart. Farris attributes the hyperaemia to the action of pituitary gonadotrophin, which shows a peak rise at the time of ovulation. This new test is certainly of scientific interest, and should prove valuable in laboratories equipped to perform it. The reading of the reaction, however, is by no means easy, and Farris admits that abnormal reactions are fairly common. We still await the simple, cheap, . reliable, easily interpreted test for ovulation which gynaecologists would find so useful. IN the
important
investigation to
FUTURE OF PREVENTIVE
INOCULATIONS
THE list of diseases for which satisfactory preventive inoculations have been discovered is ever lengthening. Dr. H. J. Parish, in his presidential address to the epidemiological section of the Royal Society of Medicine on May 23, reviewed current immunological procedures for each disease in turn. In the prophylaxis of diphtheria and tetanus, typhoid and typhus, smallpox and rabies, yellow fever and cholera, the use of an appropriate vaccine or toxoid is universally practised. Evidence of the value of pertussis vaccine is still somewhat contradictory, and the short-lived immunity obtained from influenza vaccine at present limits its application. Promising preliminary reports are appearing on the use of an attenuated mumps virus, and an effective attenuated 8. Evans, W. Lecture to the Association of Industrial Medical Officers in London on June 19, 1946. Barton, M., Wiesner, B. P. Lancet, 1945, ii, 663; Halbrecht, I. Ibid, p. 668 ; Nieburgs, H. E. Ibid, 1946, i, 627. 10. Farris, E. J. Amer. J. Obstet. Gynec. 1947, 52, 14. 9.
measles virus may in time be produced. Dr. Parish believes that advances depend on close cooperation between the immunologist, the bacteriologist, and the chemist. Many unsolved problems remain to be tackled. Knowledge of the basis of racial and species immunity
(inherent non-susceptibility) is entirely lacking. There is explanation of the immunity of man to avian tuberculosis or of dogs and goats to tetanus. Again, we know that immunisation of the pregnant mother with diphtheria prophylactic raises the circulating antibody titre of the child, but although passive immunity can be conferred on the mother by injection of diphtheria no
antitoxin in horse serum, these immune bodies do not Most exotoxins can be pass the placental barrier. measured quantitatively and qualitatively, and they are relatively stable substances ; but endotoxins are in a different category and our present understanding of their action is much less complete. Dr. Parish suggested that in the near future much effort will be expended on elucidating the antigenic structure of organisms and preparing pure stable antigens capable of exact measurement and less likely to produce allergic manifestations. Other paths of research are the use of new mineral salts to combine with antigens-such as the aluminiumphosphate diphtheria toxoid of Holt-and careful assessment of the antigenic potency of strains used in the preparation of vaccines and toxoids. The work of Barr and Glenny,l showing that higher antibody titres can be obtained with two doses of A.P.T. at a threemonthly interval (instead of the usual one month) reminds one that we do not yet know the optimum spacing or dosage of diphtheria toxoid. There is little hope, in Dr. Parish’s view, that artificial immunity will be obtained without recourse to parenteral injections, and the ideal of all antigens being administered in one single inoculation is far in the future. The growing practice, however, of combining certain antigens (e.g., diphtheria and tetanus toxoids with pertussis vaccine) should, he thought, become more common, for it reduces the number of injections without apparently reducing the immunising value of each antigen. OUT OF POCKET ENGLISH local government has a fine record of unpaid service. Those taking part have given generously of their leisure and energy, and in the past they have not grudged the expenses that went with their duties, for they were usually in a position to afford them. Today, however, with altered social and economic conditions many of those best fitted to serve on local councils can only do so at a sacrifice which we are beginning to feel it is unfair to ask them to undertake. The interdepartmental committee which have just reported2 to the Ministry of Health and the Scottish Home Department on the expenses of members of local authorities confirm these uneasy fears. From the evidence they received they gained the impression that some members were suffering undue hardship, and that suitable candidates were being deterred from standing for election by fear of expense and loss of time. They have therefore recommended that local authorities should have power to pay allowances to councillors who lose remunerative time in attending meetings and carrying out their public duties, and that councillors should be entitled to be paid travelling expenses and subsistence allowances. The principle involved is of importance to the new health service, which will depend so much on the wisdom and generosity of those who sit on its committees and boards. If we are to have practical members chosen from among working people-whatever their work _may be—it is important that no-one should be hindered from accepting office from fear of out-of-pocket expenses. J. Hyg. Comb. 1945, 44, 135. 1. Barr, M., Glenny, A. T. H.M. Stationery Office. Pp. 51. 1s. 2. Cmd. 7126.