Use of Oral Cholera Vaccine and Knowledge, Attitudes, and Practices Regarding Safe Water, Sanitation and Hygiene in a Long-Standing Refugee Camp, Thailand, 2012-2014

Given the relatively new use of oral cholera vaccines (OCVs) in public health programmes, there is limited information on the impact of OCV use on traditional water, sanitation, and hygiene (WaSH) activities - i.e., can they serve as complementary tools, or will OCV use have a negative impact on WaSH-related behaviours? This study reports the findings of knowledge, attitudes, and practices (KAP) surveys conducted before and after a preventive OCV campaign (2013) in Maela, a long-standing refugee camp in Thailand, where frequent cholera outbreaks had occurred in recent years.

The 2-dose OCV campaign in Maela camp was implemented by Première Urgence-Aide Médicale Internationale (PU-AMI) with technical assistance by the U.S. Centers for Disease Control and Prevention (CDC) in 3 rounds during January–March 2013, with support from the Thailand Ministry of Public Health (MOPH) and the Bill and Melinda Gates Foundation. Immediately after the baseline KAP survey in December 2012, PU-AMI delivered information about the OCV campaign to camp leaders in meetings and to the community through posters, school presentations, loud-speaker announcements, and household visits. Documentation of campaign-associated messaging was reviewed and found to include reference to information about OCV (e.g., 2-dose requirement, limited vaccine efficacy, and duration of immunity), handwashing, and cholera prevention practices. Routine provision of WaSH services by Solidarités International, or SI (the water and sanitation non-governmental organisation, or NGO) continued per their mandate, and no additional WaSH interventions were conducted before, during, or immediately after the OCV campaign. Between 3 and 12 months following the campaign, SI conducted additional WaSH educational activities, including dramatic performances on cholera prevention, handwashing campaigns, and screenings of "The Story of Cholera" film by the Global Health Media Project.

The researchers conducted cross-sectional household-level surveys 1 month before the OCV campaign during November-December 2012 (baseline), 3 months after the campaign during May-June 2013 (first follow-up), and 12 months after the campaign in March 2014 (second follow-up). In total, 271 (77%), 187 (81%), and 199 (85%) households were included in the baseline, first, and second follow-up surveys, respectively. Despite repeated outbreaks and outbreak response efforts in Maela refugee camp during 2005-2010, baseline cholera knowledge and safe water practices were generally low (45-70%). Anticipated OCV acceptability was 97% at baseline, and 91% and 85% of household members were reported to have received 1 and 2 OCV doses at first follow-up. Compared with baseline, statistically significant differences (95% Wald confidence interval not overlapping zero) were noted at first and second follow-up among the proportions of respondents who correctly identified 2 or more means of cholera prevention (62% versus 78% and 80%), reported boiling or treating drinking water (19% versus 44% and 69%), and washing hands with soap (66% versus 77% and 85%); a significant difference was also observed in the proportion of households with soap available at handwashing areas (84% versus 90% and 95%), consistent with reported behaviours. No significant difference was noted in the proportion of households testing positive for Escherichia coli in stored household drinking water at second follow-up (39% versus 49% and 34%).

With regard to vaccine KAPs, at baseline, 135 (50%) of 271 respondents could name 2 or more diseases prevented by vaccines, and 107 (39%) respondents claimed to have heard of "cholera vaccine". Overall, 11 (4%) respondents reported having any concerns about adults in the household receiving vaccines, and 17 (7%) reported concerns about children in the household receiving vaccines. In total, 231 (86%) of 271 respondents reported a household member receiving any vaccine; 220 (97%) and 217 (95%) of 228 respondents reported a child in the household receiving polio drops and a measles injection, respectively. Compared with baseline, the proportion of respondents in the first follow-up survey mentioning cholera as a disease they knew to be prevented by vaccine increased 19% (95% confidence interval (CI): 11%-26%), and those reporting they had heard of "cholera vaccine" increased 55% (95% CI: 48%-61%). In the second follow-up survey, changes in vaccine KAPs that were sustained from the first follow-up survey relative to baseline included a 27% (95% CI: 19%-35%) increase in the proportion of respondents who named cholera as a disease prevented by vaccine, and a 53% (95% CI: 47%-60%) increase in those who had heard of "cholera vaccine". Changes observed in the second follow-up survey, but not in the first follow-up survey, included 19% (95% CI: 10%-27%) more respondents mentioning 2 or more diseases prevented by vaccines and 6% (95% CI: 2%-10%) fewer respondents reporting concerns about children in the household receiving vaccines, compared to baseline.

In short, "[a]t first follow-up, the results showed modest improvements (6-15% increase) in knowledge of cholera prevention and treatment, as well as reported use and observation of soap for handwashing in the household, in the absence of a change in the reported receipt of soap for cholera prevention. These improvements were sustained at second follow-up, with additional positive and no negative long-term changes noted....[t]he modest KAP improvements at first follow-up generally correlated with the focus areas for campaign messaging - cholera prevention and handwashing. The majority of respondents received the proper messaging concerning the limited duration and protection of OCV, another focus of campaign messaging. More improvements in WaSH knowledge and practices were observed at second follow-up than first follow-up compared with baseline; likewise, reports of hearing about and receiving printed educational materials for cholera prevention increased. The contribution of the OCV campaign to improvements in WaSH KAPs occurring between the first and second follow-up surveys could not be evaluated relative to the WaSH educational activities documented to have been conducted by SI during this timeframe. It is possible that in Maela and similar settings with ongoing WaSH activities (e.g., home visits, dramas), high-profile OCV campaigns may provide increased visibility to cholera-related issues that may contribute to people remembering more after the campaign, thereby reinforcing repeated WaSH messaging."

In conclusion: "WaSH remains the mainstay of cholera prevention and control, but providing OCVs in conjunction with WaSH interventions may be particularly useful in settings with limited safe water and sanitation infrastructure, such as refugee camps....[S]ince OCV campaigns have the potential to be high-profile activities with high acceptability and uptake, we recommend planned integration of strong WaSH messaging towards achieving comprehensive cholera prevention and control in high-risk communities globally. Further pre- and post-evaluations of the impact of OCV campaigns on WaSH KAPs are needed from other settings....We recommend including household observations and other objective measures to distinguish changes in reported KAPs from actual behavior changes."