ABSTRACT.
Most cholera outbreaks in Bangladesh are seasonal, peaking in the dry and post-monsoon periods. Therefore, we investigated whether changes in water, sanitation, and hygiene (WASH) behavior in three populations in Bangladesh during the year could help explain why these two periods are particular to cholera transmission. The study used a mixed-method design, including a repeated cross-sectional study, focus group discussions, and key informant interviews. Through a repeated cross-sectional study, WASH-related variables were assessed during the dry, monsoon, and control seasons in 600 households from coastal Satkhira, inland Sirajganj, and the Dhaka slums. Seasonal behavioral changes were observed in all study areas. Dhaka and Satkhira had an increased mean distance to water sources during the dry and monsoon seasons (Dhaka: control season, 12 m [95% CI, 11–13]; dry season, 36 m [95% CI, 18–55]; and monsoon season, 180 m [95% CI, 118–243]; Satkhira: control season, 334 m [95% CI, 258–411]; dry season, 669 m [95% CI, 515–822]; and monsoon season, 2,437 m [95% CI, 1,665–3,209]). The participants attributed this to pollution of the usual water source. Perceived water quantity was lowest during the dry season in Dhaka and Sirajganj, and during the monsoon season in Satkhira. Handwashing with soap declined in all areas during the dry and monsoon seasons. Open defecation was frequent among children younger than 5 years, increasing during seasonal climate hazards. Results show that WASH-related behavior changed seasonally, increasing the risk of cholera transmission through multiple hygiene-related transmission pathways. Future research would benefit by ensuring that the length of studies covers all seasons throughout the year and also by looking in more detail at people’s behavior and hygiene practices.
INTRODUCTION
Bangladesh is a cholera-endemic country that experiences two cholera peaks each year. The first occurs in the dry season, usually between March and May, and primarily affects the coastal regions. The second and larger peak occurs in the post-monsoon season from September to December and mainly affects inland areas.1,2 Dhaka, Bangladesh’s capital, located centrally, experiences both peaks. The seasonality of cholera peaks in Bangladesh raises the question of whether the seasonal climatic hazards that Bangladesh experiences during the dry and monsoon seasons, including flooding, waterlogging, and dry season water stress and salinity intrusion (the movement of salty seawater into fresh aquifers inland), can disrupt normal hygiene behavior, increasing the risk of cholera transmission.3
Drinking water contaminated with Vibrio cholerae is a well-researched source of cholera transmission.4–9 However, drinking water is not the only route of contamination, and from the F diagram developed by Wagner and Lanoix,10 we know that unsafe disposal of cholera patients’ feces can lead to cholera infection through various routes. Especially for cholera, the influence of water accessibility and the consequent lack of household and personal hygiene can be important factors in cholera transmission.11 Although extensive research exists on the role of handwashing with soap in controlling cholera,12–15 little is known about the seasonal handwashing behavior of people living in cholera-affected environments. In a randomized controlled trial of hospital-based hygiene and water treatment intervention, Zohura et al.16 found that only 4% of the study participants used soap for handwashing. The few studies of handwashing behavior for cholera control in Bangladesh have shown rates of between 22% and 28% of soap availability in a community setting.17
Many studies have investigated the association between diarrhea transmission and changes in water, sanitation, and hygiene (WASH) caused by major disasters.18–20 However, the impact on households of smaller disruptions, seasonal climatic hazards, water sources, sanitation, and hygiene in Bangladesh has been little researched.
We aimed to investigate changes in behavioral WASH patterns in Bangladesh during three different seasons by assessing changes in distance to water sources, perceived water quantity, handwashing behavior, and open defecation practices.
MATERIALS AND METHODS
Three study areas were selected based on their different geographic locations in Bangladesh and exposure to seasonal environmental conditions (Table 1). The coastal Satkhira District is vulnerable to cyclones, waterlogging from monsoon rains, and saltwater intrusion. The Sirajganj District is situated inland along the Jamuna River and is exposed to annual river flooding and waterlogging from monsoon rains. Last, Dhaka city slums struggle with waterlogging annually during the monsoon season.
Table 1.
Participant sociodemographic characteristics
| Characteristic | Dhaka (n = 588) | Satkhira (n = 598) | Sirajganj (n = 576) |
|---|---|---|---|
| Female gender, % | 51.5 | 50.0 | 51.9 |
| Age, y; mean (SD) | 35.4 (11.4) | 40.7 (11.9) | 39.1 (8.8) |
| Occupation, % | |||
| Salaried job | 61.4 | 46.4 | 16.9 |
| Homemaker | 35.5 | 23.6 | 40.1 |
| Agriculture | 0.0 | 27.1 | 40.3 |
| Other | 3.1 | 1.2 | 2.9 |
| Illiterate, % | 62.9 | 47.3 | 71.9 |
| No. family members, mean (SD) | 4.7 (1.5) | 5.0 (1.8) | 4.6 (1.7) |
| No. children > 5 y, mean (SD) | 0.8 (1.0) | 0.5 (0.7) | 0.5 (0.7) |
The study used a mixed-methods approach involving a repeated cross-sectional survey that was triangulated with focus group discussions and key informant interviews. The quantitative data from the repeated cross-sectional survey and qualitative data from the focus groups and key informant interviews were collected concurrently from April 2011 to March 2012 to compare WASH behaviors among populations in the three different geographic environments at the same three points in time: dry season (May 2011), monsoon season (August 2011), and a control period of relative normality in terms of extreme weather events (February 2012).
To gather the quantitative data, we enrolled 200 households in each area, resulting in 1,800 surveys. The sample size for the survey was calculated using the total population of the study areas, a confidence level of 95%, and a CI of ±4%, which determined that 600 households would need to be enrolled in the study.
To select the participating households randomly, a multistage sampling method was used. In the first stage, five unions in each study area (a union is the lowest level of local government and consists of multiple villages) were selected randomly by drawing the names of the unions from a hat. Thereafter, four villages per union were selected by drawing the names of the villages from a hat, and 10 households per village were selected by dropping a pen in the village center and surveying every 10th household while walking in the direction toward which the pen tip pointed.
The surveys included sociodemographic questions and WASH questions, including the type of water source (e.g., rainwater, tube well, pond sand filter, direct from a pond, river) for different household uses (such as drinking, cooking, water applied to food after cooking, washing dishes, washing clothes, handwashing, and bathing), distance to the water source (in meters), perceived water quantity (more than enough, enough, or not enough), handwashing behavior before eating and after defecation (washing one, both, or no hands and using soap, ash/soil, or only water), and open defecation behavior of children and adults.
The surveys were conducted in Bengali by trained enumerators from the Environment, and Population Research Center (EPRC), and the results were coded and translated into English for analysis. A population-based approach was considered best suited to answering the research question. Therefore, descriptive analysis to identify population behavioral trends and frame the findings within ongoing cholera research was the method considered to use the collected data. Descriptive and univariate analyses were conducted using IBM SPSS Statistics version 27 (SPSS Inc., Chicago, IL).
To triangulate the quantitative results and gain further depth of understanding, qualitative data were gathered through 14 focus groups and 11 key informant interviews. Focus groups were held separately for men and women. Key informant interviews were held with government officials, health workers, nongovernmental organization representatives, and local shop owners. The focus group and key informant interview questions were similar to those in the quantitative survey, investigating how water use, sanitation practices, and hygiene behavior changed seasonally.
In addition, based on respondents’ answers, probing questions were asked to investigate the research question further. For example, as respondents brought up financial challenges resulting from seasonal hazards, probing questions were asked about how this financial impact affected the household’s choices related to water use, sanitation practices, and hygiene behavior.
The focus groups and key informant interviews were cofacilitated by a Bangladeshi project manager from the EPRC and S. L. G. with the support of an experienced translator. Notes were taken in both Bengali and English and compared for validation. Bengali notes were translated into English for analysis. The data were coded and grouped into themes that emerged from the data.
Themes from the qualitative data were analyzed in light of the quantitative results. Although questions in the focus groups and key informant interviews focused on the same general categories used in the quantitative survey (i.e., seasonal changes in water use, sanitation practices, and hygiene behaviors), themes emerged from the qualitative data that spanned these categories, including how changes in the household economic situation throughout the different seasons impact the household’s decision making in terms of water use, sanitation, and hygiene. In other cases, the qualitative data helped gain a deeper understanding of the quantitative results, such as understanding the importance that households placed on preserving a high quality of drinking water year round, even during times of water scarcity, compared with a lessor effort that households made to preserve the quality of water for other household uses, including hygiene.
RESULTS
Because of missing data for a few participants, 1,762 study participants were included in the analysis. The sociodemographic characteristics were similar in the three study areas, except for occupation and illiteracy rates (Table 1).
Water source.
The type of water source the participants used primarily for water collection differed among the study areas, but there was no trend in seasonality. The most commonly used water sources in Dhaka were “supply water” (water from the city’s piped water supply system; 76–83%); in Satkhira, pond filters (pond water filtered through sand and brick chips; 50–93%); and in Sirajganj, tube wells (water wells in which a stainless steel pipe or tube is bored into an underground aquifer; 99–100%). The participants in Satkhira reported changes in water sources during the monsoon season, with 32% relying on rainwater.
In Dhaka and Satkhira, the median distance to the water sources increased during the dry and monsoon seasons compared with the control season. In Sirajganj, however, no major changes in the distance were identified during the different seasons (Table 2).
Table 2.
Distance to the water source in all study areas during three seasons
| City and season | n | Mean distance to water source, m (95% CI) | Minimum distance to water source, m | Median distance to water source, m | Maximum distance to water source, m |
|---|---|---|---|---|---|
| Dhaka | |||||
| Control | 196 | 12 (11–13) | 0.5 | 13 | 50 |
| Dry | 199 | 36 (18–55) | 0.4 | 10 | 1,250 |
| Monsoon | 193 | 180 (118–243) | 1.0 | 60.0 | 3,240 |
| Satkhira | |||||
| Control | 199 | 334 (258–411) | 0.0 | 25 | 2,500 |
| Dry | 199 | 669 (515–822) | 250 | 1,000 | 2,500 |
| Monsoon | 200 | 2,437 (1,665–3,209) | 3 | 650 | 12,000 |
| Sirajganj | |||||
| Control | 179 | 40 (33–48) | 1 | 25 | 400 |
| Dry | 199 | 23 (18–28) | 2 | 15 | 400 |
| Monsoon | 198 | 39 (30–48) | 2 | 10 | 400 |
During the focus groups and key informant interviews in coastal Satkhira, the respondents explained that during the monsoon season, rainwater was often collected in relatively small, open containers. When those containers were empty, they would have to walk, sometimes far, to collect water.
In a focus group discussion in inland Sirajganj, the respondents revealed that, although the type of source often stays the same throughout the year, the source’s specific location can change from one season to another. An example was given of a family using a neighbor’s tube well because their own well had flooded during the monsoon season. One respondent in Sirajganj said, “We use the flood water for everything except for drinking. We can hardly manage enough water to drink. The water we use for other things, don’t ask.”
Perceived water quantity.
Perceived water quantity varied among the study areas and seasons. In Dhaka and Sirajganj, similar trends were observed. The greatest proportion of participants reporting having more than enough water was during the control season (18% and 13%, respectively), dropping to 0% to 3% during the dry and monsoon seasons. The greatest proportion of participants reporting not having enough water occurred during the dry season: 21% in Dhaka and 42% in Sirajganj. In Satkhira, the greatest proportion reported having more than enough water (9%) but also not enough water (29%) during the monsoon season. In inland Sirajganj, respondents stated in the focus groups that shallow tube wells yield less or even dry out in the dry season, creating water quantity challenges.
Handwashing behavior.
A trend of decreased soap use during the dry and monsoon seasons was identified across all areas in handwashing behavior before eating and after defecation (Figures 1 and 2). Rates of soap use were consistently greater in all areas after defecation than before eating, ranging from 2% to 12% before eating and from 15% to 82% after defecation in Dhaka; in Satkhira, from 0% to 48% and 27% to 58%, respectively; and in Sirajganj, from 7% to 26% and 6% to 42%, respectively.
Figure 1.
Distribution of handwashing behavior (by agent) before eating per area and season.
Figure 2.
Distribution of handwashing behavior (by agent) after defecation per area and season.
In addition, especially in Dhaka, more participants reported washing both hands after defecation (46–61%) compared with before eating (8–23%). These trends were also observed in Sirajganj, but to a lesser degree (46–61% after defecation versus 29–63% before eating). In Satkhira, no such trend was identified, and the rates for washing both hands after defecation (30–83%) were similar to the rates before eating (34–96%).
The focus group participants reported that soap was considered a luxury. As a result of unexpected costs arising from seasonal hazards, they did not have enough money throughout the whole year to afford soap. A man in a focus group with community members in inland Sirajganj stated, “We cannot afford a proper house [one that is made out of tin]. How can we afford soap?” Similarly, a respondent in a focus group with farmers and fishermen in Sirajganj said, “All we think about is surviving the day; if everything is okay, then we can try to think about hygiene.”
Open defecation behavior.
Open defecation was not commonly practiced among the adults (0–4%) but was frequent among the children, ranging from 11% to 76%, depending on the area and/or the season. Children’s open defecation behavior increased during the monsoon season compared with the control season in all areas (Figure 3). In Dhaka, the frequency of open defecation practices among children rose from 11% during the control season to 25% during the monsoon season; in Satkhira, from 27% to 37%; and in Sirajganj, from 15% to 51%. An even greater increase during the dry season was observed in Sirajganj, with 76% of children practicing open defecation.
Figure 3.
Distribution of open defecation behavior among children younger than 5 years per area and season.
DISCUSSION
Distance to water sources.
Our results show that the participants used the same type of water source if the current source flooded or ran dry; consequently, they had to walk farther to the next, similar undisrupted water source. The change of water sources during flooding could be a result of people living in the three study areas in Bangladesh having a high awareness of the risk of polluted water sources for cholera transmission and other diseases or disliking the taste of the polluted water. In a taste-testing experiment in Satkhira, the participants did not tolerate water with salinity levels high enough to support the growth of V. cholerae, which is typically found when water sources are flooded in coastal areas in Bangladesh.21 Despite the reason for the change, increased distances to water sources will decrease households’ water availability, potentially decrease hygiene levels, and potentially increase diarrhea risk.22
Perceived water quantity.
The increased transport distance of water was reflected in perceived water quantity. Participants faced challenges in maintaining sufficient amounts of water for drinking and hygiene purposes during seasonal hazards.
As the cholera peaks in Bangladesh occur at the same times during the dry season and immediately after the monsoon season, water disruptions and low water quantity have been identified previously as important contributors to cholera transmission.23–25 Further research is needed to investigate this phenomenon.
Moreover, when only low quantities of water are available, people living in Bangladesh have reported focusing primarily on collecting safe water for drinking purposes but also using water from polluted sources for hygiene purposes.26
Handwashing behavior.
Our findings suggest that declining soap use during seasonal hazards is a result of a lack of availability or accessibility, rather than awareness. The focus group participants reported that soap was a luxury they could not afford when unexpected costs arose during seasonal hazards.
Our results show more soap use and thorough handwashing behavior after defecation compared with before eating, indicating that the participants might perceive proper hygiene measures (and washing both hands) after defecation as more important than proper hygiene measures before eating. Research has focused increasingly on the role of unhygienic kitchen environments for cholera transmission. Vibrio cholerae and other diarrhea-causing bacteria have been identified in kitchen environments, including plates, food, surfaces, and knives, in several studies in Bangladesh.23,27,28 The role of unhygienic kitchen environments, including insufficient handwashing, may be an important contributor to cholera transmission and is under-researched compared with many WASH variables.
With a decline in soap use, alternative handwashing agents, such as soil and ash, increased during the dry and monsoon seasons, especially after defecation, compared with the control season. This could indicate that soap use declined because of a lack of availability or accessibility, and the participants therefore replaced soap with cheaper or more available alternatives.
In addition, cross-contamination or recontamination of water from unpolluted water sources at the point of use for hygiene purposes in the household might be an overlooked driver for cholera transmission behavior.11,13,24,25,29
Open defecation behavior.
Increased rates in open defecation practices among children during the monsoon season in all study areas are concerning, especially considering the risk of rainwater transporting feces to new sites. In addition, people practicing open defecation may be less likely to wash their hands after defecation (because of the unavailability of water) than those using sanitation facilities.
Limitations.
This study has several limitations. First, missing data resulted in small sample sizes for some variables. Although we aimed to record the answers of 200 households per season and area, for some variables, the data were incomplete. Either the participants did not answer all the questions or answers were lost during the process of digitizing. Because the analysis focused on population proportions, no problem was identified with a slightly decreased sample size for some of the variables as a result of missing data. However, when interpreting the data, the lower accuracy of the results on variables with fewer respondents was considered. Second, social desirability bias might have influenced some survey answers, such as on handwashing behavior. Ecological data and descriptive statistics cannot identify correlations, and more research is needed to test the hypotheses.
CONCLUSION AND FURTHER PERSPECTIVES
This study identified that seasonal hazards caused by the dry season or monsoon rains influenced several WASH-related behavioral practices by the studied populations in Bangladesh. Throughout the seasons, participants changed their water source but continued to use the same type of water source. This shows that their choice of water is driven by a perception of water quality, usually preferring to walk longer distances to be able to collect water from an unpolluted water source. This will affect the quantity of water used by the household negatively. If questionnaires are not designed carefully, this important information will be lost. Participants are usually asked about the type of water source used, especially during flooding, not taking into account that even though the type of water source is the same, the location of the water source might not be the same, leading the researcher to conclude falsely that participants are drinking from a potentially polluted source. In addition, seasonality can impact handwashing behavior in terms of the use of soap, ash, or soil and whether one hand or both hands are washed. Future, more detailed questionnaires must take into account not only how people wash their hands, but also using which medium (soap, ash, soil, etc.).
Our study also shows how the length of a study is important in detecting behavioral changes throughout different seasons, particularly when it comes to hygiene practices and open defecation among children, which remains a major concern throughout the seasons and study areas. Future studies should take at least 1 year to cover and collect information from all seasons. Furthermore, based on our findings, under-researched areas, such as the role of kitchen hygiene, cross-contamination, and water quantity, should be investigated further to understand and combat cholera transmission routes fully.
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