pesticides enhance economic potential through increased food and fiber production as well as through control of vector - borne diseases .
this ease of availability has resulted in a gradual increase in accidental and suicidal poisoning [ 14 ] .   globally ,
each year , poisoning due to organophosphorus compounds is responsible for approximately three million episodes that result in nearly 200  000 deaths .
the vast majority of these occur in developing countries like india , as a result of fatal pesticide self - poisoning [ 68 ] .
however , developing countries account for only 20% of global pesticide use .   on the morning of 2 february 2008
, residents of sindhikela village , bolangir district , in the indian state of orissa were admitted to the hospital with complaints that included vomiting , profuse sweating and fits . some were in serious condition .
sindhikela is a small village with a poor rural population , where people sometimes do not have the resources to cook themselves breakfast : they eat a snack on the street instead . as a response to the alert
, the additional district medical officer ( public health ) and a graduate from the indian field epidemiology training programme ( fetp ) proceeded to the village immediately with the district task force to identify for the cause of the outbreak and ensure preventive and control measures .
we defined a case as occurrence of vomiting and profuse sweating between 6:00 am and 8:00 am on 2 february 2008 in a resident of sindhikela .
we plotted an epidemic curve , drew a map of the residence of the case patients , and calculated age and sex specific attack rates to describe   the outbreak by time , place , and person . to identify risk factors we conducted a case control study .
we included all cases as defined above and recruited controls as the healthy neighbors of case patients .
we collected information from the case patients and the control subjects on symptoms , date and time of onset , source of food taken in the last 24 hours and drinking water source .
we compared the frequency of exposure variables between cases and controls through odds ratio with 95% confidence intervals .
we collected residual specimens of food from a roadside eatery that we suspected as a possible source and sent them to a laboratory .
we collected water specimens from different drinking water sources and sent them for chemical analysis to the public analyst , state surveillance cell , bhubaneswar , the state capital .
sindhikela is located 100  km away from bolangir ( 2008 population : 5263 ; male / female : 2680  :  2613 ) .
we confirmed the occurrence of an outbreak as 65 cases and two deaths were reported within an hour in the context of a background rate of less than one hospitalization per month ( overall attack rate : 12 per 1000 , case fatality : 3% ) .  
the distribution of cases over time ( figure 1 ) pointed to an initial peak of 33 cases between 6:15 am and 6:30   am followed by a decline and two last cases at 7:15 am , suggesting a point source outbreak .
the spot map ( figure 2 ) indicated that there was a clustering of cases in harijanpada and hatpada , two adjacent localities of the village .
the attack rate per 1000 was the highest among the 5 to 8 years of age and among males ( table 1 ) .
vomiting and sweating were present in all cases ( as per our definition ) ; whereas 77% had myosis and 31% convulsions ( figure 3 ) .
the proportion of case patients with convulsions decreased with age , from 83% ( 10/12 ) among children 04 years of age , to 60% ( 6/10 ) among 58 children years of age , to 17% ( 2/12 ) among children 913 years of age to 6% ( 2/31 ) among persons 14 years of age and older ( p < .001 , chi square , 3 degrees of freedom ) . the point source pattern of the outbreak and the clustering in a specific location close to a roadside eatery led us to suspect a mixed foodborne and waterborne origin .
we included all 65 patients cases and 65 healthy neighbors as controls in our case control analysis .
however , cases were more likely to be children 013 years ( or : 3 , 95% confidence interval [ c.i . ] : 1.46.2 , table 2 ) .
consumption of water from a specific source ( or : 35 , c.i . : 1393 ) and eating at the roadside eatery ( or : 2.3 , c.i . : 1.14.7 ) was associated with illness ( table 2 ) .
48 cases and 36 controls had eaten in that roadside eatery that morning ( the eatery was popular , even among small children ) . in an analysis restricted to those who had eaten in the eatery ,
cases were more likely to have eaten pakoda with a water - based chutney preparation ( or : 3.9 , c.i . :
neither the food specimens nor the vomitus collected from three case patients grew any organism on culture . on 31 january 2008 , some villagers had used a pesticide ( folidol ec 50 , an emulsifiable concentrate ) to kill street dogs .
pipelines supplying drinking water that were damaged at many places were located beneath the drain .
these pipelines supplied drinking water twice a day , while during the rest of the time , they had a negative pressure .  
on 2 february 2008 early in the morning ( 6 am ) , when the first phase of drinking water was supplied to harijanpada , it may have rinsed off pesticide that had been aspirated in the pipelines during the nocturnal phase of negative pressure .
the owner of the small roadside eatery near harijanpada collected water from that particular point to prepared pakoda and the water - based chutney .
this leads to accumulation of acetylcholine resulting in over stimulation of muscarinic and nicotinic receptors of skeletal muscles .
the case patients during this outbreak had a typical syndrome of organophosphorous poisoning . however , we could not do any serological test to exclude another etiology nor estimate the serum cholinesterase and red blood cell cholinesterase levels .
further , autopsy could not be practiced on the two deceased case - patients because they died on their way to the hospital .
we treated patients at the sindhikela community health center , referred serious cases to subdivisional hospital , titilagarh , and to a medical college hospital in burla .
the population of the village frequently used folidol   to kill rats and street dogs , an inappropriate indication .
after the dogs were killed , the containers with the residual insecticide could have contaminated the drinking water as the damaged pipe lines were going right beneath the drains and presented negative pressure .
the actual product that was used , folidol ec 50 , is an emulsifiable concentrate , a who class i product . those are actually banned for use in india ( the villagers reported that they used an old stock procured before the ban ) .
an accidental poisoning of a less potent organophosphorous ( who class ii or iii ) would have been unlikely to have lead to this many casualties .
in addition to deliberate self - poisoning with pesticide , the burden of accidental poisoning with organophosphorous is unclear , because these episodes are not systematically reported .
as an example , in 2006 , in the same area of bolangir , in the state of orissa , we investigated a cluster of 33 cases of organophosphorous poisoning secondary to inhalation of themit .
the cluster occurred among agricultural workers who were planting in a paddy field that had been recently sprayed .
because of the nature of their activity , they were working with their face less than a meter away from the ground . if it were not for the presence of an epidemiologist from the field epidemiology training programme ( fetp ) of india posted in the district ( an unusual event given the number of trainees and the size of the country ) , this cluster would not have been reported .  
we stopped supplying the suspected contaminated drinking water and provided alternate drinking water through tankers .
we discussed with villagers the issue of safe drinking water and proper handling of pesticides ( including abstaining from inappropriate indication such as use to kill dogs ) .
, systematic epidemiological investigations such as the one we report must be conducted for clusters of toxicoses of unknown origin .  
facilities to diagnose organophosphorous poisoning in relevant health care facilities and systematic reporting of clusters would also provide additional capacity to document and prevent such occurrences .
 introduction . we investigated a cluster of pesticide poisoning in orissa . 
 methods . 
 we searched the village for cases of vomiting and sweating on 2 february 2008 . 
 we described the outbreak by time , place , and person . 
 we compared cases with controls . 
 results . 
 we identified 65 cases ( two deaths ; attack rate : 12 per 1000 ; case fatality : 3% ) . 
 the epidemic curve suggested a point source outbreak , and cases clustered close to a roadside eatery . 
 consumption of water from a specific source ( odds ratio [ or ] : 35 , confidence interval [ ci ] : 1393 ) and eating in the eatery ( or : 2.3 , ci : 1.14.7 ) was associated with illness . 
 on 31 january 2008 , villagers had used pesticides to kill street dogs and had discarded leftovers in the drains . 
 damaged pipelines located 
 beneath and supplying water may have aspirated the pesticide during the nocturnal negative pressure phase and rinsed it off the next morning in the water supply . 
 conclusions . 
 innapropriate use of pesticides contaminated the water supply and caused this outbreak . 
 education programs and regulations need to be combined to ensure a safer use of pesticides in india . 
1. Introduction
2. Method
3. Result
4. Discussion