Cholera is spread by faecal contamination of water and food, with endemicity and epidemicity closely linked to poor sanitation often accompanying natural disasters and situations that crowd people together under poor sanitary conditions that interrupt access to clean water. V. cholerae colonizes the lining epithelium of the gut, resulting in an acute, profuse watery diarrhea with children and the elderly particularly vulnerable.
For many years killed whole-cell Cholera vaccine was the only vaccine available which was administered by injection. However, this vaccine offers at best only limited protection of short duration, it does not prevent transmission of the infective agent, and it produces unpleasant side-effects in many patients. In view of these limitations, the vaccine has not been considered satisfactory for general public health use, and in 1973 the World Health Assembly abolished the requirement established by the International Health Regulations for a certificate of vaccination against cholera. Because the inactivated vaccine is no longer recommended for general public health use (although it is still produced in some countries), the Expert Committee for Biological Standardization discontinued the requirements relating to the parenteral whole-cell vaccine in 1999.
Cholera Vaccine Standardization
WHO guidelines for inactivated oral cholera vaccines were which were adopted by the Expert Committee on Biological Standardization in 2001 describe the characteristics, production and control of inactivated oral cholera vaccines. This document was prepared to facilitate progress towards the international licensure and use of the new generation of oral vaccines against cholera.
Guidelines for the production and control of inactivated oral cholera vaccine, Annex 3, Technical Report Series 924, 2004
WHO reference reagents for the Inaba and Ogawa cholera vaccine antigens are available to qualified applicants: