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Cholera Vaccine and International Travel
1369
THE
LANCET
vaccine gave some 70% protection for a similar period. But the incidence of cholera in villages provided with simple sanitary facilities was reduced by about 70% in 3 years and cost-benefit analysis has
confirmed that this is
Cholera Vaccine and International Travel IN 1971, cholera became once again a dominant
global public-health problem. A major epidemic occurred in India among the refugees from Bangladesh, and outbreaks of cholera were reported from forty-two countries. Fourteen countries in East and West Africa, in North Africa, in the Arabian peninsula, and in Europe experienced the disease for the first time. There were some 150,000 reported cases of the disease-three times as many as in 1970.1 Emergency assistance was provided through the World Health Organisation by a score of contributing countries. Supplies of rehydration fluid, antibiotics,
bacteriological media, diagnostic antisera, vaccine, and vaccination equipment were promptly dispatched to the centres of distribution. Many lives were saved and in some areas the epidemics soon abated. The number of reported cases of cholera increased in 1972 to some 170,000, but this reflects improved epidemiological surveillance of the disease; about 100,000 cases were notified in fourteen countries of Asia, and 70,000 cases in twenty-two countries of Africa, and 121 cases of imported infection were recorded in several European countries.22 However, while the geographical spread of cholera is still very wide, the size and severity of outbreaks has certainly decreased. The spread of this, the seventh, pandemic of cholera was largely due to the El Tor biotype of Vibrio cholerae, which causes many mild or symptomless infections.33 Greatly increased population mobility by air, sea, rivers, and land, together with poor sanitary conditions in congested areas in developing countries, are responsible for the new situation.4 Since improvement of environmental conditions such as proper sewage disposal and provision of safe water-supplies demands time and is expensive, much reliance has been placed on vaccination against cholera, which was first introduced in 1884 by FERRAN (a pupil of PASTEUR) and used with some success by HAFFKINE in 1892 in India. Belief in the efficacy of vaccine to deal with any large-scale outbreak of cholera has been dispelled by two controlled field trials.5,6 In the Philippines,5 monovalent Inaba and Ogawa parenteral vaccines were given in an area where the causal organism is the Ogawa serotype. The Inaba vaccine gave about 60% protection for 6 months, while the Ogawa 1. The Work of
W.H.O., 1971. Off. Rec. no. 197. World Health Organisation, Geneva. 2. Wkly epidem. Rec. 1972, no. 30. 3. Cvjetanovic, B., Barua, D. Nature, 1972, 239, 137. 4. Lapeyssonnie, L. Thesis. University of Montpellier, 1972. 5. Azurin, J. C., et al. Bull. Wld Hlth Org. 1967, 37, 703. 6. Mosley, W. H., Bart, K. J., Sommer, A. Int. J. Epidem. 1972, 1, 5.
more
permanent and than
econ-
vaccination.
advantageous omically Lately, two investigations7,8 in Bangladesh, carried out by the Cholera Research Laboratory at Dacca, indicated that there was no appreciable difference in more
mass
the incidence of infection in two groups of contacts of cholera patients-one group being given a monovalent Inaba vaccine and the other a placebo. Massvaccination programmes are of little value as a public-health measure because the short duration of protection and the high cost of vaccination force the authorities to postpone the campaign until clinical cases become apparent; by then, intervention is too late to stem the outbreak. In these circumstances, tetracycline is a more effective prophylactic agent. Control of cholera depends on the establishment and maintenance of a level of sanitation that will 3 prevent faecal/oral transmission of the pathogen.3 A safe piped water-supply, good methods of sewage disposal, improved housing conditions-all these are better long-term investments in health than any largescale immunisation programmes with the existing, not very satisfactory, vaccines. Nevertheless, immunisation reduces quite substantially the risk to individuals and should be made available to those particularly exposed to the infection. Medical personnel and travellers proceeding to countries where cholera is prevalent should be protected by vaccination. The vaccine, while offering partial protection, does not prevent people from becoming carriers of the disease. Surveillance and treatment are sufficient to contain the infection if it is introduced. Many countries, including the U.K., require travellers coming from certain countries to produce valid international certificates of vaccination against cholera. The U.S. Public Health Service,9 having recognised the limited value of vaccination against
cholera,
no
longer requires
a
certificate of travellers
the U.S.A. from cholera-infected areas. This stand has now been endorsed by the 26th World Health Assembly, which introduced a change in the International Health Regulation so that henceforth vaccination against cholera shall not be required as a condition of admission of any individual traveller The question of removing cholera to a country from the list of diseases covered by the International Health Regulations was discussed, but the 1973 World Health Assembly wisely decided that this would be inappropriate, since it might imply that cholera is no longer a serious public-health problem. This is certainly not so, and the continuing menace
coming
to
Sommer, A., Khan, M., Mosley, W. H. Lancet, June 2, 1973, p. 1230. 8. Sommer, A., Mosley, W. H. ibid. p. 1232. 9. Communicable Disease Center. Morbidity and Mortality. ACIP Recommendations, 1972, no. 21. 10. World Health Organisation. Press release WHA/18, May 23, 1973. 7.
1370
of cholera should serve as a reminder that the improvement of environmental health in this shrinking world is more important than every
HERNIOGRAPHY
INGUINAL hernia is one of the commonest reasons for admission of a child to hospital for surgical treatment, yet accurate diagnosis of this simple anomaly appears still to be extremely difficult. Gilbert and Clatworthy,12 in 164 patients who were each examined more than once by an experienced pxdiatric surgeon, found the diagnosis was wrong in 400,’,. White, Haller, and Dorst 13 likewise found an error of 40% in the clinical diagnosis, even though each patient was examined by three surgeons. What is worse, diagnosis was equally fallible in children over the age of two years. Opinion is divided on how often a hernia which does not give rise to symptoms or physical signs will be present on the other side. Roew et aI. 14 came to the conclusion that 40% of 1900 patients they examined had an open hernial sac on the opposite side and that half of these subsequently had symptoms of herniation. It is not surprising, therefore, that a number of surgeons have recommended exploration of the opposite side even when symptoms are confined to one hernia, on the ground that this avoids readmission of the child to hospital and a second anxsthetic and operation. Obviously, half the operations will be unnecessary; they are also more likely to be associated with damage to the testicular artery, veins, or vas, since absence of a hernia leads to more intensive dissection in the search for the hernial sac. Various methods have been proposed to make preoperative diagnosis of hernia more exact. One is to try to pass a sound or bougie through the hernial sac on the side which is giving rise to symptoms into the hernia on the opposite side; another is injection of radio-opaque medium into the peritoneal cavity, followed by X-ray examination of the patient in the The report of upright position (herniography). Ducharme et al.,15 in which radiological diagnosis was wrong only 3 times in 60 patients, has been followed by a number of others.13.ic-is Blau et al.l8 recommend insertion under local analgesia of an 18-gauge arterial catheter into the peritoneal cavity through a small incision just below the umbilicus. They then inject up to 30 ml. of meglumine iothalamate in a 60% solution (which they believe causes less discomfort than other solutions). Care is taken to reduce any known hernia and the patient is exercised for five minutes, infants being gently shaken in the upright position. X-rays are then taken 5 minutes and 15 11. Department of Health and Social Security. Communicable Diseases Contracted Outside Great Britain. London, 1972. 12. Gilbert, M., Clatworthy, H. W. Am. J. Surg. 1959, 97, 255. 13. White, J. J., Haller, J. A., Dorst, J. P. Surg. Clins N. Am. 1970 50, 823. 14. Rowe, M. I., Copelson, L. W., Clatworthy, H. W. J. pediat. Surg 1969, 4, 102. 15. Ducharme, J. C., Bertrand, R., Chacar, R. J. Can. Ass. Radiol 1967, 18, 448. 16. White, J. J., Parks, L. C., Haller, J. A. Surgery, St. Louis, 1968 17. 18.
63, 991. Swischuk, L. E., Stacy, R. M. Radiology, 1971, 101, 139. Blau, J. S., Keating, T. M., Stockinger, F. S. Surgery Gynec Obstet. 1973, 136, 401.
minutes after the injection. As well as carrying out this procedure, Blau et al. operated on both sides irrespective of whether or not a hernia had been demonstrated radiologically. Operation confirmed that they had made the diagnosis correctly in every The risk of perforating one of their 40 patients. a distended bladder is reduced by getting the patient to pass urine before the catheter is inserted. Allergic reactions to the contrast medium have not been reported, but care should be taken not to perforate the bowel when the catheter is pushed into the
peritoneal cavity. Herniography appears to be a reliable method of diagnosing symptomless hernias in infants, and so far no serious complications have been reported. The in situations be where the errortechnique may justified rate is high, 12,13but centres with lower rates of diagnostic failure will probably be unwilling to adopt itespecially as a means of excluding bilateral hernia in the four out of five patients who have symptoms on only one side. It is unlikely to be adopted by surgeons who do not feel compelled to explore both sides routinely when history and physical examination suggest hernia on only one side. Herniography is most likely to appeal to surgeons who do not habitually deal with children, in the hope that their occasional foray into this area will be made more productive by more reliable diagnosis. But these are just the circumstances in which the technique is least likely to commend itself to those who prefer to treat children in children’s hospitals. Herniography involves radiological examination of the pelvis and gonads in either undesirable in practice-even pxdiatric radiological departments, where radiation dosage is consistently and conscientiously controlled. In many adult radiological departments, control of the dosage and technique for X-raying children and babies compares poorly with that in paediatric radiological departments, and undesirable exposure to radiation is a distinct hazard. sex, and for this reason alone it seems an
CR
IN part 11 of their inquiry into the riot-control agent CS the Himsworth Committee 19 spelled out a principle relating to any decision to release chemical agents for use in civil disturbances-namely, that medical and scientific research relevant to such a decision should be published. This did not happen with CS. Will it happen with the successor to CS ? The signs are not encouraging. Strictly speaking, the Himsworth is not relevant to CR, for no decision to yet principle use it in Northern Ireland or anywhere else in the United Kingdom has yet been taken. However, the Ministry of Defence now confirms that CR is in production 20 and the U.S. Army may shortly decide to adopt CR as its agent of choice. 21Little enough was known about CS when it caught the attention of newsmen and scientists alike in 1969, but even less is known about CR at a time when it could, on a minister’s say-so, be used tomorrow. Report of the Enquiry into the Medical and Toxicological Aspects of CS: part II. Cmnd. 4775. H.M. Stationery Office, 1971. 20. Times, June 7. 21. Jones, R. New Scientist, May 31, p. 546. 19.
THE
LANCET
vaccine gave some 70% protection for a similar period. But the incidence of cholera in villages provided with simple sanitary facilities was reduced by about 70% in 3 years and cost-benefit analysis has
confirmed that this is
Cholera Vaccine and International Travel IN 1971, cholera became once again a dominant
global public-health problem. A major epidemic occurred in India among the refugees from Bangladesh, and outbreaks of cholera were reported from forty-two countries. Fourteen countries in East and West Africa, in North Africa, in the Arabian peninsula, and in Europe experienced the disease for the first time. There were some 150,000 reported cases of the disease-three times as many as in 1970.1 Emergency assistance was provided through the World Health Organisation by a score of contributing countries. Supplies of rehydration fluid, antibiotics,
bacteriological media, diagnostic antisera, vaccine, and vaccination equipment were promptly dispatched to the centres of distribution. Many lives were saved and in some areas the epidemics soon abated. The number of reported cases of cholera increased in 1972 to some 170,000, but this reflects improved epidemiological surveillance of the disease; about 100,000 cases were notified in fourteen countries of Asia, and 70,000 cases in twenty-two countries of Africa, and 121 cases of imported infection were recorded in several European countries.22 However, while the geographical spread of cholera is still very wide, the size and severity of outbreaks has certainly decreased. The spread of this, the seventh, pandemic of cholera was largely due to the El Tor biotype of Vibrio cholerae, which causes many mild or symptomless infections.33 Greatly increased population mobility by air, sea, rivers, and land, together with poor sanitary conditions in congested areas in developing countries, are responsible for the new situation.4 Since improvement of environmental conditions such as proper sewage disposal and provision of safe water-supplies demands time and is expensive, much reliance has been placed on vaccination against cholera, which was first introduced in 1884 by FERRAN (a pupil of PASTEUR) and used with some success by HAFFKINE in 1892 in India. Belief in the efficacy of vaccine to deal with any large-scale outbreak of cholera has been dispelled by two controlled field trials.5,6 In the Philippines,5 monovalent Inaba and Ogawa parenteral vaccines were given in an area where the causal organism is the Ogawa serotype. The Inaba vaccine gave about 60% protection for 6 months, while the Ogawa 1. The Work of
W.H.O., 1971. Off. Rec. no. 197. World Health Organisation, Geneva. 2. Wkly epidem. Rec. 1972, no. 30. 3. Cvjetanovic, B., Barua, D. Nature, 1972, 239, 137. 4. Lapeyssonnie, L. Thesis. University of Montpellier, 1972. 5. Azurin, J. C., et al. Bull. Wld Hlth Org. 1967, 37, 703. 6. Mosley, W. H., Bart, K. J., Sommer, A. Int. J. Epidem. 1972, 1, 5.
more
permanent and than
econ-
vaccination.
advantageous omically Lately, two investigations7,8 in Bangladesh, carried out by the Cholera Research Laboratory at Dacca, indicated that there was no appreciable difference in more
mass
the incidence of infection in two groups of contacts of cholera patients-one group being given a monovalent Inaba vaccine and the other a placebo. Massvaccination programmes are of little value as a public-health measure because the short duration of protection and the high cost of vaccination force the authorities to postpone the campaign until clinical cases become apparent; by then, intervention is too late to stem the outbreak. In these circumstances, tetracycline is a more effective prophylactic agent. Control of cholera depends on the establishment and maintenance of a level of sanitation that will 3 prevent faecal/oral transmission of the pathogen.3 A safe piped water-supply, good methods of sewage disposal, improved housing conditions-all these are better long-term investments in health than any largescale immunisation programmes with the existing, not very satisfactory, vaccines. Nevertheless, immunisation reduces quite substantially the risk to individuals and should be made available to those particularly exposed to the infection. Medical personnel and travellers proceeding to countries where cholera is prevalent should be protected by vaccination. The vaccine, while offering partial protection, does not prevent people from becoming carriers of the disease. Surveillance and treatment are sufficient to contain the infection if it is introduced. Many countries, including the U.K., require travellers coming from certain countries to produce valid international certificates of vaccination against cholera. The U.S. Public Health Service,9 having recognised the limited value of vaccination against
cholera,
no
longer requires
a
certificate of travellers
the U.S.A. from cholera-infected areas. This stand has now been endorsed by the 26th World Health Assembly, which introduced a change in the International Health Regulation so that henceforth vaccination against cholera shall not be required as a condition of admission of any individual traveller The question of removing cholera to a country from the list of diseases covered by the International Health Regulations was discussed, but the 1973 World Health Assembly wisely decided that this would be inappropriate, since it might imply that cholera is no longer a serious public-health problem. This is certainly not so, and the continuing menace
coming
to
Sommer, A., Khan, M., Mosley, W. H. Lancet, June 2, 1973, p. 1230. 8. Sommer, A., Mosley, W. H. ibid. p. 1232. 9. Communicable Disease Center. Morbidity and Mortality. ACIP Recommendations, 1972, no. 21. 10. World Health Organisation. Press release WHA/18, May 23, 1973. 7.
1370
of cholera should serve as a reminder that the improvement of environmental health in this shrinking world is more important than every
HERNIOGRAPHY
INGUINAL hernia is one of the commonest reasons for admission of a child to hospital for surgical treatment, yet accurate diagnosis of this simple anomaly appears still to be extremely difficult. Gilbert and Clatworthy,12 in 164 patients who were each examined more than once by an experienced pxdiatric surgeon, found the diagnosis was wrong in 400,’,. White, Haller, and Dorst 13 likewise found an error of 40% in the clinical diagnosis, even though each patient was examined by three surgeons. What is worse, diagnosis was equally fallible in children over the age of two years. Opinion is divided on how often a hernia which does not give rise to symptoms or physical signs will be present on the other side. Roew et aI. 14 came to the conclusion that 40% of 1900 patients they examined had an open hernial sac on the opposite side and that half of these subsequently had symptoms of herniation. It is not surprising, therefore, that a number of surgeons have recommended exploration of the opposite side even when symptoms are confined to one hernia, on the ground that this avoids readmission of the child to hospital and a second anxsthetic and operation. Obviously, half the operations will be unnecessary; they are also more likely to be associated with damage to the testicular artery, veins, or vas, since absence of a hernia leads to more intensive dissection in the search for the hernial sac. Various methods have been proposed to make preoperative diagnosis of hernia more exact. One is to try to pass a sound or bougie through the hernial sac on the side which is giving rise to symptoms into the hernia on the opposite side; another is injection of radio-opaque medium into the peritoneal cavity, followed by X-ray examination of the patient in the The report of upright position (herniography). Ducharme et al.,15 in which radiological diagnosis was wrong only 3 times in 60 patients, has been followed by a number of others.13.ic-is Blau et al.l8 recommend insertion under local analgesia of an 18-gauge arterial catheter into the peritoneal cavity through a small incision just below the umbilicus. They then inject up to 30 ml. of meglumine iothalamate in a 60% solution (which they believe causes less discomfort than other solutions). Care is taken to reduce any known hernia and the patient is exercised for five minutes, infants being gently shaken in the upright position. X-rays are then taken 5 minutes and 15 11. Department of Health and Social Security. Communicable Diseases Contracted Outside Great Britain. London, 1972. 12. Gilbert, M., Clatworthy, H. W. Am. J. Surg. 1959, 97, 255. 13. White, J. J., Haller, J. A., Dorst, J. P. Surg. Clins N. Am. 1970 50, 823. 14. Rowe, M. I., Copelson, L. W., Clatworthy, H. W. J. pediat. Surg 1969, 4, 102. 15. Ducharme, J. C., Bertrand, R., Chacar, R. J. Can. Ass. Radiol 1967, 18, 448. 16. White, J. J., Parks, L. C., Haller, J. A. Surgery, St. Louis, 1968 17. 18.
63, 991. Swischuk, L. E., Stacy, R. M. Radiology, 1971, 101, 139. Blau, J. S., Keating, T. M., Stockinger, F. S. Surgery Gynec Obstet. 1973, 136, 401.
minutes after the injection. As well as carrying out this procedure, Blau et al. operated on both sides irrespective of whether or not a hernia had been demonstrated radiologically. Operation confirmed that they had made the diagnosis correctly in every The risk of perforating one of their 40 patients. a distended bladder is reduced by getting the patient to pass urine before the catheter is inserted. Allergic reactions to the contrast medium have not been reported, but care should be taken not to perforate the bowel when the catheter is pushed into the
peritoneal cavity. Herniography appears to be a reliable method of diagnosing symptomless hernias in infants, and so far no serious complications have been reported. The in situations be where the errortechnique may justified rate is high, 12,13but centres with lower rates of diagnostic failure will probably be unwilling to adopt itespecially as a means of excluding bilateral hernia in the four out of five patients who have symptoms on only one side. It is unlikely to be adopted by surgeons who do not feel compelled to explore both sides routinely when history and physical examination suggest hernia on only one side. Herniography is most likely to appeal to surgeons who do not habitually deal with children, in the hope that their occasional foray into this area will be made more productive by more reliable diagnosis. But these are just the circumstances in which the technique is least likely to commend itself to those who prefer to treat children in children’s hospitals. Herniography involves radiological examination of the pelvis and gonads in either undesirable in practice-even pxdiatric radiological departments, where radiation dosage is consistently and conscientiously controlled. In many adult radiological departments, control of the dosage and technique for X-raying children and babies compares poorly with that in paediatric radiological departments, and undesirable exposure to radiation is a distinct hazard. sex, and for this reason alone it seems an
CR
IN part 11 of their inquiry into the riot-control agent CS the Himsworth Committee 19 spelled out a principle relating to any decision to release chemical agents for use in civil disturbances-namely, that medical and scientific research relevant to such a decision should be published. This did not happen with CS. Will it happen with the successor to CS ? The signs are not encouraging. Strictly speaking, the Himsworth is not relevant to CR, for no decision to yet principle use it in Northern Ireland or anywhere else in the United Kingdom has yet been taken. However, the Ministry of Defence now confirms that CR is in production 20 and the U.S. Army may shortly decide to adopt CR as its agent of choice. 21Little enough was known about CS when it caught the attention of newsmen and scientists alike in 1969, but even less is known about CR at a time when it could, on a minister’s say-so, be used tomorrow. Report of the Enquiry into the Medical and Toxicological Aspects of CS: part II. Cmnd. 4775. H.M. Stationery Office, 1971. 20. Times, June 7. 21. Jones, R. New Scientist, May 31, p. 546. 19.