|© CDC/Dr. Kashmira Date (photo from Bangladesh, 2011)|
|Oral cholera vaccine demonstration project in Bangladesh brings an additional solution to cholera control in the high risk areas.|
The incidence of cholera in on the rise, with more than 589,854 cases and 7,186 deaths reported worlwide in 2011, representing an 85% increase in the number of cases from the previous year (1). However, these data are considered a significant underestimate. The actual burden of cholera worlwide is estimated to range between 1.4 million to 4.3 million cases, resulting in between 28,000 to 142,000 deaths, among the 1.4 billion people at risk in endemic countries (2). Children under five bear the greatest burden of cholera in endemic areas, and account for about half of the estimated cholera deaths (3). There is an increased frequency of large and protracted cholera outbreaks with high mortality, reflecting the weaknesses of existing mechanisms for prevention, early detection, control of spread and access to timely health care. According to the World Health Organization cholera is re-emerging as a threat on the global public stage (4).
Cholera control strategies that do not include vaccination are well known, including early detection and case management to limit illness and death and access to safe water, sanitation and hygiene practices to prevent and reduce spread, yet cholera remains poorly controlled in both outbreak and endemic countries. These strategies require dedicated support systems for surveillance and early warning, coordination, assessing risk, preparedness planning, suppy chain logistics and social mobilization that are resourced and supported by governments and partners.
Oral cholera vaccines (OCV) constitute a safe, effective, and acceptable additional public health tool for cholera control to supplement existing priority cholera control measures and to respond to the growing concern of chlera as a public health threat. To this end and to improve the availability of OCV for rapid response to outbreaks, WHO convened a working group in April 2012 to reinforce the development of OCV stockpile and develop an implementation framework. Participants advised on the criteria for choice of stockpiled vaccine and its deployment; the appropriate size of an OCV stockpile; the managing partnership and evaluation processes required; the decision-making procedure and operational issues; and the financing mechanism. UNICEF is an active member of this group.
UNICEF is commited to address the evolving threat of cholera and to reduce the impact on vulnerable communities. As part of its strategic and integrated approach to cholera control, UNICEF advocates for the inclusion of OCV into cholera control strategies along with known interventions to contribute to the reduction in the spread and limit illness and death from cholera, particularly in high risk areas and among most vulnerable populations. To that effect, UNICEF has issued a guidance note on the use of OCV for UNICEF country offices and is engaged as a key partner in global, regional and national level initiatives for their use.
(1) Cholera 2011 Weekly Epidemiological Record (WER) No. 31-32, 2012, 87, 289-304 http://www.who.int/wer/2012/wer8731_32.pdf
(2) Ali M, Lopez AL, You YA, Kim YE, Sah B, Maskery B, Clemens J. The global burden of cholera. Bull World Health Organization, 2012, 1; 90(3): 209-218A http://www.who.int/bulletin/volumes/90/3/11-093427/en/
(3) Deen JL et al. The high burden of cholera in children: comparison of incidence from endemic areas in Asia and Africa. PLoS Neglected Tropical Diseases 2008, 2(2): e173. http://www.ncbinlm.nih.gov/pmc/articles/PMC2254203/pdf/pntd.0000173.pdf
(4 Martin S, Costa A, Perea W. Stockpilling oral cholera vaccine. Bull World Health Organization, 2012; 90: 714 http://www.who.int/bulletin/volumes/90/12-112433.pdf