Oral Cholera Vaccine Development and Use in Vietnam

ThreatThe emergence of cholera in Haiti highlighted the difficulties in containing cholera outbreaks with only safe water, sanitation, hygiene, and appropriate case management.In less developed settings where cholera occurs, these basic needs are often not met or are rapidly overwhelmed during man-made or natural disasters.Prior to the Haitian outbreak, countries in Africa and Asia had borne most of the cholera burden, with an estimated 1.4 billion people at risk, 2.8 million cases, and 100,000 to 200,000 deaths occurring annually [1,2]; however, because of difficulties in surveillance and differences in reporting systems, only 245,393 cases with 3,034 deaths were reported to the World Health Organization (WHO) in 2012 [1].This figure does not include the large number of acute watery diarrhoea cases reported in Asia, of which a significant proportion is caused by Vibrio cholerae.As cholera continues to be a global public health problem, in 2011, the World Health Assembly called for an integrated and comprehensive approach to cholera control, including oral cholera vaccines (OCVs) [3].OCVs have been available for more than 20 years, but public health use has been limited.Vietnam is the first and currently the only country in the world to use killed OCVs routinely in its public health program.This article describes the cholera problem in Vietnam and how an oral cholera vaccine was developed and used as a component of a public health strategy against the disease. Cholera in VietnamCholera has been endemic in Vietnam since 1964, when V. cholerae O1 El Tor was first identified in the country.Vietnam uses the term ''severe watery diarrhoea'' for culture-confirmed cases of cholera or clinically diagnosed cholera during an outbreak.Reports of cholera are forwarded to and collated by the Epidemiology Unit of the National Institute of Hygiene and Epidemiology (NIHE) under the Ministry of Health (see Text S1 and Table S1).From 1991 to 2001, reported cases of severe watery diarrhoea were highest in the South Central Coast, followed by the North Central Coast.During the same period, Hue province in the North Central Coast had the highest annual incidence rate of severe watery diarrhoea cases, with the majority of cases coming from itsThe Health in Action section provides a place where groups or individuals who are not represented regularly in a medical journal have a forum to describe the important issues from their perspective.Authors might include patient advocacy groups, healthcare workers, or non-governmental organizations.