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Recent large epidemics of cholera with high incidence and associated mortality among refugees have raised the question of whether oral cholera vaccines should be considered as an additional preventive measure in high-risk populations. The potential impact of oral cholera vaccines on populations prone to seasonal endemic cholera has also been questioned. This article reviews the potential cost-effectiveness of B-subunit, killed whole-cell (BS-WC) oral cholera vaccine in a stable refugee population and in a population with endemic cholera. In the population at risk for endemic cholera, mass vaccination with BS-WC vaccine is the least cost-effective intervention compared with the provision of safe drinking-water and sanitation or with treatment of the disease. In a refugee population at risk for epidemic disease, the cost-effectiveness of vaccination is similar to that of providing safe drinking-water and sanitation alone, though less cost-effective than treatment alone or treatment combined with the provision of water and sanitation. The implications of these data for public health decision-makers and programme managers are discussed. There is a need for better information on the feasibility and costs of administering oral cholera vaccine in refugee populations and populations with endemic cholera.

A clinical trial was carried out with 126 male patients over 2 years of age suffering from diarrhoea requiring intravenous rehydration, 80 of the patients suffering from cholera and 46 from non-cholera diarrhoea. A new "diarrhoea treatment solution" (DTS) containing sodium at a concentration of 118 mmol/litre and glucose at 44 mmol/litre was compared with the usual Dacca intravenous solution (DS) which has a sodium concentration of 133 mmol/litre and contains no glucose. The other constituents and their concentrations were the same in both solutions. All the patients responded well clinically and made an uneventful recovery. Oral water intake measured during the first 24 h was higher in the group receiving the DS. This group also excreted a significantly higher quantity of sodium in the urine. A significant fall in the level of blood glucose from the admission values occurred in both the groups; the fall was relatively less in the DTS group, this solution containing 44 mmol of glucose per litre. Further work is required to find the optimum concentration of glucose in the solution for infants and young children.

Despite the progress that has been made in the treatment of cholera, mortality rates from this disease remain high in rural areas where intravenous fluids are not readily available. The authors have therefore conducted controlled studies into the efficacy of a simpler form of maintenance therapy-the administration of glucose-containing electrolyte solutions by mouth. The results obtained from the study of 51 adult patients (36 with cholera and 15 with severe non-cholera diarrhoea) indicate that oral fluids are adequate for maintenance therapy in cholera and severe diarrhoeal disease, and that there is no significant increase in the duration of diarrhoea or in the stool volume in patients receiving such therapy.The addition of a non-specific adsorbent, charcoal, to the fluid led to a significant increase in the volume of diarrhoeal stools and to prolongation of vibrio excretion; its use is therefore not recommended. The use of oral replacement solutions should result in improvement of cholera treatment of adults in rural areas and in a reduction in the cost of treatment.

Because of the relative difficulty in maintaining continuous intravenous infusions in small children suffering from cholera, a simpler method of maintenance fluid therapy would be useful. With this in mind, the role of intraperitoneal fluid administration was evaluated in 8 adults and 26 children (aged 6 years or less) having moderate to severe cholera or cholera-like diarrhoeal disease.In adults intraperitoneal fluid was found to be of no significant value in maintenance therapy because peritoneal absorption was not sufficiently rapid to replace expected stool losses. In children, however, this form of therapy was considerably more successful. In 16 of 19 children with cholera and in all 7 with non-cholera diarrhoea, intraperitoneally administered fluid was absorbed rapidly enough to replace a major part of the initial fluid deficit on admission and all subsequent stool losses. No complications of intraperitoneal puncture were encountered.

This study reports the use of bacteriophage prepared in the USSR in the treatment of cholera. Patients with acute cholera were rehydrated with a standard intravenous solution and were then given a bacteriophage preparation in addition to maintenance intravenous therapy. The titre of the phage preparations was between 10(8) and 10(9) pfu/ml. Bacteriophage was given by mouth (25 ml for adults and 20 ml for children) for 3 days; in addition, some patients were also given an intramuscular injection (20 ml) of phage on the first day in hospital. For comparison, other groups of patients were given a standard tetracycline regimen or a placebo preparation. Daily vibrio and phage counts were made on stool samples from all patients and the vibrio strains isolated from each patient were tested for sensitivity to the phage preparation.The criteria used to evaluate the various therapies were duration of diarrhoea, volume of stool, and duration of vibrio excretion.The results of the study demonstrate that, in the doses used, the therapeutic effect of bacteriophage, if any, was markedly inferior to that of tetracycline and that in the current state of our knowledge bacteriophage, as used in this study, has no place in the treatment of cholera.

Each member of a group of 8 patients with acute cholera was treated with a mixture of four cholera bacteriophage preparations containing over 2 x 10(12) phage particles/ml. These massive doses were intended to kill immediately all vibrios in the intestine by "lysis from without". The numbers of Vibrio cholerae were drastically reduced rapidly. In 4 patients, V. cholerae was completely eliminated from the stools early in the treatment; the total stool volume and after-treatment of diarrhoea were reduced in comparison with a control group but were higher than in a group of patients treated with tetracycline. In the other 4 patients treated with phage, vibrios disappeard more slowly from the stools and there was no apparent clinical effect of the phage. In all the patients treated with phage, the duration of diarrhoea was longer than in patients in a control group who excreted vibrios for a similar length of time although the stool output was similar. This was interpreted as being due to the persistence of vibrios in foci of infection in the upper intestine.It is concluded that treatment of cholera with massive doses of bacteriophage is not as effective as treatment with tetracycline. However, phage can selectively eliminate the majority of vibrios without affecting the other intestinal flora and without any apparent toxic effect on the patient. Phage might therefore be useful as a research tool.