food- and waterborne illnesses are a growing public health problem worldwide . food contaminated with microorganisms such as parasites , microbes , and other pathogens is the main cause . the most virulent pathogens causing food- and waterborne diseases are campylobacter , escherichia coli , salmonella , and shigella . according to the center for disease control , a food- and waterborne disease outbreak occurs when two or more people have the same disease from a common contaminated food or drink source . the prevalent symptoms include an upset stomach , abdominal cramps , vomiting , diarrhea , fever , and dehydration . according to the who ,  millions of people become ill and shigellosis is responsible for 80 million cases of dysentery and 700,000 deaths due to dysentery in the world . who suggests several preventive keys for safe food , including keeping the food clean , separating raw and cooked foods , keeping food at safe temperatures , and using safe water and raw materials . most studies have indicated that the knowledge about food- and waterborne outbreaks is low especially in young age groups [ 710 ] . the knowledge , attitude , and practice ( kap ) studies are one of the best ways of assessing knowledge , attitude , and practice of individuals . the current study was conducted during and following the diarrhea outbreak in the cities of zarach , ardakan , and meybod located in yazd on august 9 , 2013 . a case of diarrhea was defined as an episode with three or more watery stools over a period of 24 hours , with or without other symptoms during the outbreak period . one of the main reasons for conducting this study was to compare knowledge , attitude , and practice of affected communities ( the cities of zarach , meybod , and ardakan ) and nonaffected communities ( the cities of yazd and taft ) . knowledge , attitude , and practice ( kap ) study was conducted from august to september 2013 in yazd province , which is located in the center of iran . yazd province , with an area of 131,551  km and a population of 972,781 people , is located as an oasis in the dasht - e kavir desert . yazd province is divided into 9 cities including abarkuh , ardakan , bafq , khatam , meybod , mehriz , sadough , taft , and yazd . we conducted our study in the cities of zarach , meybod , ardakan , yazd , and taft ( see figure 1 ) . our study encompassed 505 people aged over 15 years who were visited at different health centers in yazd province from 27 august to 10 september 2013 during the epidemic . we conducted this survey during the diarrhea outbreak . between august 9 and september 27 , 2013 , a diarrhea outbreak occurred in the cities of meybod , ardakan and zarach . we considered these cities as affected cite and the neighboring cites ( yazd and taft ) were considered as nonaffected cites . the sample size was calculated based on a pilot study . in the pilot study , the prevalence of weak practice regarding food- and waterborne diseases was estimated to be 27% . assuming the prevalence of weak practice regarding food- and waterborne diseases , the sample size was 259 with the significance level set at 0.05 . because we had two communities ( yazd and taft as nonaffected communities of diarrhea outbreak and meybod , ardakan , and zarach as affected communities ) the questionnaire consisted of four sections as follows : ( a ) 18 questions on general characteristics such as gender , education level and history of severe diarrhea in the past 30 days , and the main source of health information obtaining in the past 30 days ; ( b ) 12 questions related to knowledge of food- and waterborne diseases including three - choice questions ( yes / no / do not know ) and five - choice questions ( a / b / c / d / do not know ) , with a total score between zero and 36 ; ( c ) 10 five - choice questions ( strongly agree / agree / no idea / disagree / strongly disagree ) related to attitude toward food- and waterborne diseases , with a total score between zero to 50 ; and ( d ) nine questions related to practice on food- and waterborne diseases , with a total score between zero to 27 . we considered high knowledge , positive attitude , and good practice if participant answered %75 of the questions correctly , moderate knowledge , attitude , and practice if they answered 6074% of the questions correctly , and low knowledge , negative attitude , and weak practice if they answered < 60% of the questions correctly . the reliability of the questionnaire was investigated by conducting a pilot study on 30 people . the value of cornbrash 's alpha coefficient for the knowledge and attitude questions was 0.60 . also , the sample size calculated according to a pilot study , bases on the weak practice proportion ( 0.27 ) . analysis of variance was used to compare the mean score of knowledge , attitude , and practice across subgroups . an adjusted linear regression model was employed to estimate the effect of knowledge , attitude , and other related factors on practice regarding food- and waterborne outbreaks . all analyses were performed at the 5% significance level ( p < 0.05 ) using stata 12 ( statacorp , college station , tx , usa ) . from 505 subjects enrolled in the study , 54.46% ( 275 ) were female and 45.54% ( 230 ) were male . the total mean score of the participants ' knowledge , attitude , and practice regarding food- and waterborne diseases was 28.17 ( sd = 4.58 ) , 37.07 ( sd = 4.39 ) , and 21.17 ( sd = 3.81 ) , respectively . sixty - four percent of the participants had high knowledge and good practice regarding food- and waterborne outbreaks and 43% of them had a positive attitude . nonaffected communities by the diarrhea outbreak ( yazd and taft cites ) had high mean scores of knowledge , attitude , and practice in comparison with the affected communities ( meybod , ardakan and zarach ) . however , only the difference in the mean score of knowledge was significant ( p = 0.037 ) . the mean of knowledge and practice scores in females was high ( 28.73 sd = 4.13 , 21.77 sd = 3.75 , resp . ) in comparison with males ( p = 0.001 ) . married participants had high mean scores of knowledge and practice ( 28.0 sd = 1.41 , 22.0 sd = 1.41 ) in comparison with singles ( p = 0.004 , p = 0.019 , resp . ) . the maximum knowledge was observed in > 60-year - old participants ( 29.87 , sd = 3.18 , p < 0.001 ) , and the maximum mean of attitude and practice was seen in participants aged 2540 years ( p = 0.057 , p = 0.240 ) , too . the housekeeper 's knowledge and practice were higher in comparison with other family members ( p = 0.001 , p = 0.015 ) but householders had a better attitude ( p = 0.042 ) . participants reported television and health centers as the main sources of obtaining health information in the past 30 days ( 38% and 31.27% , resp . ) . the mean scores of knowledge and practice among people who reported health centers as the main sources of obtaining health information were high ( p = 0.011 and p = 0.105 , resp . ) . the maximum scores of knowledge and attitude were in 46-person families ( p = 0.053 and p = 0.012 , resp . ) . the mean scores of knowledge , attitude , and practice of people who had severe diarrhea in the past 30 days were low ( p = 0.01 , p = 0.029 , and p = 0.168 , resp . ) ( see table 1 ) . according to adjusted linear regression analysis , practice regarding food- and waterborne diseases increased 0.08% per one - unit increase in the score of knowledge ( p < 0.001 ) and 0.16% per one - unit increase in the score of attitude ( p < 0.001 ) . also , people who had academic education had 6.01 times better practice regarding foodborne and waterborne outbreaks in comparison with illiterate participants ( p < 0.001 ) ( see table 2 ) . the total mean scores of knowledge , attitude , and practice based on primary categorization were acceptable . our result indicated that the average of kap was low in affected communities ( zarach , meybod , and aradakan ) . the low level of kap can be a predisposing factor ( condition ) to a diarrhea outbreak . this finding is also reported in several studies [ 9 , 10 , 13 ] and is corresponding to this finding of our study that the mean scores of knowledge and practice were highest among housekeepers ( since the majority of housekeeper are female ) , too . one of the possible reasons for this may be the fact that housewives spent more time obtaining health information from sources such as television and health centers , so that obligatory educational program could be improving the level of knowledge of men . the result of analysis of variance showed that with the increase in the level of education in men , the mean score of kap increases but the maximum mean of kap scores was observed in illiterate most justifiable reason result in low sample size ( n = 9 ) in illiterate group and subsequently the probability of random error occurrence . framers had best practice against food- and waterborne outbreaks in comparison with other jobs but this statistically significant relation may be not true , because of very low sample ( n = 6 ) in farmers category and consequently increasing probability of selection bias occurrence . the maximum mean scores of knowledge , attitude , and practice were observed among people who reported health centers as the main sources of obtaining health information in the past 30 days . on the other hand , 38% ( maximum value ) of the people with high knowledge reported health centers as main sources of obtaining health information . this finding indicates the effective role of health centers in increasing the level of knowledge . the mean scores of knowledge , attitude , and practice of people who had severe diarrhea in the past 30 days were low . these mean differences may introduce that , with the low level of knowledge , negative attitude , and weak practice , people become more susceptible to get food- and waterborne diseases as a hypothesis . thus this finding indicated kap study may be useful tool for identifying high risk group who gets food- and waterborne disease . mpazi and mnyika   reported that 83% of the women and 87% of the men had high knowledge about foodborne diseases , with nonsignificant relation with high response rate ( 84.4% ) . in our study , the response rate was high but 69% of the women and this difference may be due to different categorization of knowledge in the design of the studies . another study conducted by saleeon   showed that 57% , 48% , and 89% had high mean scores of knowledge , attitude , and practice , respectively . in our study , the mentioned scores were 63.17% , 39.21% , and 63.96% , respectively . in both studies , about 7582% referred to the fact that they always boiled canned food for 2030 minutes before consuming it . about 99% of the participants in a study by askarian et al . and 70% of the participants in our study believed that they had to separate raw and cooked foods . in a study by unusan , participants knew nausea ( 69% ) , fever ( 6.1% ) , and diarrhea ( 5% ) as the symptoms of food- and waterborne diseases while in our study , 14% , 81.91% , and 63.76% of the participants mentioned these symptoms , respectively . reported a weak positive correlation between food safety knowledge and practices regarding food safety ; in our study , this correlation was even weaker . 
 limitations . in our study , the rejection rate was 13.09 , which could decrease generalizability . our study subjects were those who were visited at health centers , which may cause selection bias although we tried to decrease this bias with sampling from two big reference health centers located in different parts of the cities . another limitation that should be noted was the relatively low reliability ( chronbach 's alpha = 0.6 ) of the questionnaire , which may increase the information bias . nonaffected communities by the diarrhea outbreak had a considerably better practice score . with the increase in the score of knowledge about food and water outbreak ,
objective . 
 this study was conducted after a diarrhea outbreak that occurred in yazd province , iran . 
 the aim of the study was to compare knowledge , attitude , practice , and other risk factors of the affected communities regarding diarrhea outbreak ( the cities of zarch , meybod , and ardakan ) to nonaffected communities ( the cities of yazd and taft ) . 
 methods . a knowledge , attitude , and practice ( kap ) survey study was conducted from august to september 2013 enrolling 505 subjects who were referred to health centers anonymously during the epidemic . 
 the questionnaire included the following four parts : ( a ) general characteristics such as gender , education level , source of health information obtaining ; ( b ) 12 questions on knowledge ( min = 0 , max = 36 ) ; ( c ) 10 questions on attitude ( min = 0 , max = 50 ) ; and ( d ) nine questions on practice ( min = 0 , max = 27 ) . 
 results . 
 the overall mean score of knowledge , attitude , and practice was 28.17 ( sd = 4.58 ) , 37.07 ( sd = 4.39 ) , and 21.31 ( sd = 3.81 ) , respectively . 
 practice on food- and waterborne outbreaks was significantly higher in females ( p = 0.001 ) and in nonaffected communities ( p = 0.031 ) . conclusions . 
 nonaffected communities had a considerably better practice score . with the increase in the score of knowledge about food- and waterborne outbreaks , 
 the score of practice increased slightly .