Dengue is an arboviral disease caused by the Dengue Virus (DENV), belonging to the family Flaviviridae [1-4]. It is transmitted by Aedes aegypti Mosquitoes. Dengue is increasingly recognised as one of the world’s emerging infectious diseases [1,5]. The word ‘Dengue’ was derived from ‘ka-dingapepo’ which means ‘cramp like seizure’ in Swahili [2,3]. Worldwide, 50 to 100 million Dengue infections are reported annually of which 34% is from India , with a fatality rate of 0.5-3.5% in Asian countries of which 90% are children <15 years of age . According to data obtained from surveillance systems, the first known epidemic of Dengue-like illness in India was recorded in the year 1780 in Chennai, Tamil Nadu; whereas the first Dengue epidemic to be virologically confirmed was reported from Kolkata and the Eastern Coast of India in 1963-1964 . About 16517 cases and 545 deaths were reported from India during the 1996 outbreak of Dengue, after which there has been a rise in Dengue incidence from 2010 onwards . According to the National Vector Borne Disease Control Programme (NVBDCP) in 2015, 99913 cases had been reported from India which increased to 129166 cases in 2016 and reached a peak of 188401 cases in 2017. Tamil Nadu reported 23294 cases and 65 deaths due to Dengue in 2017, which represents 900 percentage spike in incidence of the disease compared to 2016 . There has been rapid geographical expansion of the virus and the vector, regular epidemics and increasing occurrence of Dengue Haemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS) in India in recent years .
The disease can be caused by any one of the four serotypes of the Dengue virus namely DENV-1, DENV-2, DENV-3 and DENV-4 and prior infection with one serotype provides lifelong immunity against that particular serotype, while the person is still susceptible to infection by any one of the remaining three serotypes [3,12,13]. Dengue fever is characterised by complex pathophysiological, economic as well as ecological challenges . Lack of awareness among people, increased urbanisation, amplified mosquito population due to deterioration in public health infrastructure and changing climatic conditions have contributed to the increased incidence of Dengue . Aedes mosquitoes breed in water storage drums, cement tanks, tyres, coconut shells and other such discarded containers which can hold rainwater . Since there is no vaccine available for Dengue prevention in the Indian market, vector control is the ideal method to control Dengue . Vector control methods can be successful only if there is community participation and for the success of community based programmes, it is important to assess the community’s perception regarding the disease, its mode of transmission and breeding sites . It is also known that human habits play a crucial role in the ecology and epidemiology of Dengue which further signifies the role of assessment of people’s knowledge, attitude and practices regarding Dengue in integrated vector control . Knowledge of the community regarding Dengue and its prevention is inadequate according to a study conducted by Varun KT et al., in Coimbatore . There exists a gap between the knowledge acquired and the application of knowledge into practices to prevent Dengue. Thus, knowledge of the community about the causes, mode of transmission, signs and symptoms and preventive measures of Dengue is of utmost importance.
Although various steps have been taken by the Government and Non-Governmental Organisations to increase awareness about Dengue, very few studies have been done in Coimbatore to determine the impact of such interventions. Thus, assessment of knowledge, attitude and practices of the community would play a very important role in guiding public administrators to plan, design and implement initiatives, programs and policies for more efficient Dengue prevention. Hence, the present study was conducted to assess the knowledge, attitude and practices regarding Dengue among the outpatients and accompanying persons attending three Primary Health Centres in Coimbatore, a city worst hit by Dengue in recent times. The present study also compares the knowledge scores between subjects based on their educational qualification in order to study the effect of education on health and disease in the community. Thus, authors wanted to study the impact of the Dengue epidemic of 2017 on people’s understanding of the disease process and preventive measures to handle such epidemics in future. This study would help in setting strategies appropriate for the implementation of various community awareness programmes and health education campaigns.
Materials and Methods
This study was a community-based cross-sectional study which was carried out among the outpatients and accompanying persons visiting three primary health care centres in Coimbatore from February to March of 2018. It was a questionnaire-based study conducted among 300 subjects. The sample size was calculated using the formula: 4pq/d2 from the study conducted by Sugunadevi G and Dharmaraj A, (p=36; q=64; d=15% of p=5.4) in Coimbatore, Tamil Nadu, India, in 2013 by consecutive sampling (non-probability sampling) . Every consecutive person visiting the three primary health centres that satisfied the inclusion criteria were included in the study. The three primary health care centres involved in the study were the Singanallur, Irugur and Sarkarsamakulam primary health centres, as these were included in the field practice area of Coimbatore Medical College. Individuals aged 18-years and above of both genders, who were both outpatients and normal accompanying persons visiting three PHCs, irrespective of whether they had been affected by Dengue in the past and those who were willing to participate in the study voluntarily and had given written informed consent regarding the same were included in the study. People aged <18-years and people who were not able to understand the questionnaire were excluded from the study. The study was conducted after obtaining clearance from the Institutional Human Ethics Committee, Coimbatore Medical College, Coimbatore (Ethics approval number: 0124/2018).
The subjects were given a pre-tested questionnaire which was validated by repeated presentations and by the faculty of the Department of Community Medicine, Coimbatore Medical College, Coimbatore and was translated into the regional language (Tamil) comprising 20 questions divided into four sections: 1) Socio demographic details such as name, age, gender and educational qualification; 2) Knowledge about Dengue-15 questions; 3) Attitude towards the disease and its management-four questions; 4) Practices related to prevention of Dengue-1 question. The questionnaires were given to the subjects after explaining the purpose of the study and making it clear that their identity would not be revealed in any aspect of the study. The 15 questions on knowledge of the disease were scored from 0 to 23. All the questions had one correct option except questions 6, 8 and 9 which had multiple correct options (The maximum score for question six was 3. The maximum score for question eight was 4. Similarly, the maximum score for question nine was 3). Each correct answer received a score of 1 and each incorrect answer, a score of 0. Subjects scoring from 0-7 were considered to have poor knowledge. Subjects scoring between 8 and 14 were considered to have average knowledge. Subjects scoring from 15-23 were considered to have good knowledge.
The study population was divided into two groups based on their educational qualification as follows: Group 1: Studied below class 10th (117 in number); Group 2: Studied above class 10th (138 in number). The two groups (subjects who had studied below class 10th and subjects who had studied above class 10th) were selected in such a way that approximately half of the subjects had studied below class 10th and the remaining half had studied above class 10th.
The collected data were entered in Microsoft Excel 2007 and analysed using SPSS software version 20.0. Descriptive statistics for the collected data were recorded and comparison of mean knowledge scores between the two groups was made using independent t-test and p-value <0.05 was taken as statistically significant.
A total of 300 individuals were approached for participation in the study of which 255 had submitted completed questionnaires, so the response rate was 85%. The subjects in the present study were aged between 18 to 75 years with a mean age of 37.47 years. Majority of the subjects were males (61.2%). Among the 255 subjects, 117 (45.88%) had studied below class 10th and the remaining 138 (54.12%) had an educational qualification above class 10th. The demographic information of the subjects is given in the table below [Table/Fig-1].
Age, gender and educational qualification of subjects.
|18-30 years||91 (35.7%)|
|31-45 years||105 (41.2%)|
|46-60 years||48 (18.8%)|
|61-75 years||11 (4.3%)|
|Below class 10th||117 (45.88%)|
|Above class 10th||138 (54.12%)|
Knowledge of Dengue fever was assessed using 15 questions aimed at ascertaining the community’s understanding of the disease process (symptoms, transmission, aetiology, vector and its breeding sites). It was observed that the majority of the study population were aware of Dengue (88.6%). It was also found that most of the subjects (80.4%) knew that Dengue was transmitted through mosquito bite. Moreover, 98% and 97.3% of subjects were aware of the breeding sites of Aedes mosquitoes inside and outside the house respectively. It was also found that knowledge of people on Dengue was lacking in several respects like signs and symptoms of Dengue (33.3%), time of the day when Aedes mosquitoes bite (34.9%) and type of water in which Aedes mosquitoes breed (40.8%). These results are depicted in [Table/Fig-2].
Response to knowledge based questions.
|S.No||Knowledge||Below class 10th (correct response) (%)||Above class 10th (correct response) (%)||Overall (correct response) (%)|
|1||Are you fully aware of Dengue?||88.9||88.4||88.6|
|2||Do you know that Coimbatore is endemic for Dengue?||65||58.7||61.6|
|3||How is Dengue transmitted?||82.9||78.3||80.4|
|4||Does transmission take place through direct contact?||30.8||31.9||31.4|
|5||Which insect species is responsible for transmitting Dengue?||32.5||48.6||41.2|
|6||What are the Signs and Symptoms of Dengue?||32.5||34.1||33.3|
|7||At what time do Aedes mosquitoes bite?||29.1||39.9||34.9|
|8||What are the breeding places outside the house?||98.3||97.8||98|
|9||What are the breeding places inside the house?||98.3||96.4||97.3|
|10||In what type of water do Aedes mosquitoes breed?||33.3||47.1||40.8|
|11||Is blood test necessary to diagnose Dengue?||93.2||93.5||93.3|
|12||Does papaya leaves and Nilavembukashayam prevent Dengue?||77.8||79.7||78.8|
|13||Are you aware about medical helpline ‘104’?||52.1||56.5||54.5|
|14||Is recurrence of Dengue possible?||53||46.4||49.4|
|15||Are you aware about steps taken by Government to prevent Dengue?||32.5||40.6||36.9|
|Average knowledge score||9.71||10.64||10.21|
The mean knowledge scores were 9.71 and 10.64 for subjects who had studied below class 10th and subjects who had studied above class 10th respectively whereas the mean knowledge score overall was 10.21. There was a statistically significant difference (p-value=0.014) in knowledge scores between subjects who had studied above class 10th and those below class 10th as shown in [Table/Fig-3].
Comparison of mean knowledge scores based on educational qualification
|Groups||Mean knowledge score±SD||p-value|
|Below class 10th (n=117)||9.71±3.23||0.014*|
|Above class 10th (n=138)||10.64±2.70|
*=statistically significant (<0.05)
Most of the present subjects had average knowledge about Dengue namely 67.5% of subjects who had studied below class 10th and 79% of subjects with educational qualification above class 10th as shown in [Table/Fig-4].
Assessment of knowledge scores.
|Knowledge (score)||Below class 10th n=117 (%)||Above class 10th n=138 (%)||Overall n=255 (%)|
|Poor (0-7)||28 (23.9)||16 (11.6)||44 (17.3)|
|Average (8-14)||79 (67.5)||109 (79)||188 (73.7)|
|Good (15-23)||10 (8.6)||13 (9.4)||23 (9)|
The attitude of the respondents was assessed using a set of four questions regarding source of information about Dengue, responsibility of controlling mosquito breeding, action on experiencing symptoms of Dengue and reason for the endemicity of Dengue in Coimbatore. Authors observed that the major source of information about Dengue was TV/Radio (46.15%) for subjects who had studied below class 10th. However, subjects with educational qualification above class 10th obtained information about Dengue mainly from Public Health Officer (32.5%), TV/Radio (31.2%) and Internet (26.7%). When it came to responsibility of controlling mosquito breeding, subjects who had studied below class 10th and above class 10th had the same attitude that it was the duty of the Government (52.13% and 42% respectively) to do so. Subjects who had studied above class 10th gave more importance to individual cleanliness (52%) in controlling mosquito breeding. Both the groups had similar understanding of the need of hospitalisation for Dengue (89.74% and 91.3% respectively). Majority of the study population irrespective of their educational qualification believed that improper sanitation was responsible for Coimbatore being endemic for Dengue (72.94%). The [Table/Fig-5] depicts the responses of the subjects to questions on attitude.
|Attitude towards Dengue|
|Variables||Below class 10th (%)||Above class 10th (%)||Overall (%)|
|Source of information|
|Public health officer||24.78||32.5||29|
|Responsibility of controlling mosquito breeding|
|Action on getting symptoms of Dengue|
|Visiting hospital immediately||89.74||91.3||90.59|
|Over the counter drugs||4.27||3.6||3.92|
|Wait for symptoms to subside||0||2.2||1.17|
|Reason for Coimbatore being endemic for Dengue|
|Inadequate medical facilities||6.83||7.88||7.45|
|Ignorance of general public||27.35||26.82||27.06|
The practice section of the questionnaire contained one question. Multiple preventive measures were followed by the subjects to prevent Dengue of which majority of the study population practised covering of water containers (63.92%), prevention of blockage of drains (56.86%) and disposal of stagnant water (50.98%). A smaller proportion of subjects used mosquito coils/nets (15.69%) and mosquito repellants (19.21%) to prevent Dengue. The [Table/Fig-6] shows the responses of the subjects to the question on practices followed to prevent Dengue.
Practices followed to prevent dengue.
|Practices followed to prevent Dengue||Below class 10th (%)||Above class 10th (%)||Overall (%)|
|Disposal of stagnant water||53.84||48.57||50.98|
|Covering water containers||64.75||62.9||63.92|
|Preventing blockage of drains||51.28||60.88||56.86|
|Changing water in plant containers||17.09||25.23||23.35|
|Adding larvicide in water containers||12.82||15.31||14.12|
|Usage of window screens||7.69||10.9||9.41|
Dengue fever is endemic in countries where half of the world’s population reside. It was initially considered to be an urban disease, but soon the disease found its way to rural communities also, due to increased transport facilities and the spread of peri-urbanisation. The consequences of Dengue depend upon the severity of the disease with simple Dengue fever causing loss of work days and severe disease in the form of DHF and DSS causing mortality. The mortality rate is higher in rural areas where facilities for the management of DHF and DSS are still far-fetched. Social and economic factors also play a major role in shaping the epidemics of Dengue. Unplanned urbanisation and lack of resources for vector control make developing countries a haven for mosquitoes and mosquito-borne diseases . Prevention of Dengue at the grass-roots level requires strong community participation and political support in the form of allocation of funds for conducting awareness programmes and health education campaigns.
The present study was a community-based cross-sectional study meant to assess the knowledge, attitude and practices regarding Dengue among adults. The present study comprised 255 subjects with 61.2% males and 38.8% females with a mean age of 37.47 years. With regard to educational qualification, 54.12% of present subjects had studied above class 10th and 45.88% had studied below class 10th.
In spite of various public awareness programmes conducted by the Government with respect to increase in Dengue in the city, 11.4% of the respondents were not aware of Dengue. In a study conducted by Itrat A et al., 10.1% of the subjects were not aware of Dengue . In a study conducted by Chellaiyan VG et al., at Kancheepuram district of Tamil Nadu, only 6.3% of the subjects had not heard of Dengue . A 61.6% of the present subjects knew that Dengue was endemic in Coimbatore.
Majority of the present subjects (80.4%) knew that Dengue was transmitted by mosquitoes similar to result of a study done by Valantine B et al., (90%) , also a study in Southern India, but only 41.2% correctly identified Aedes mosquitoes as the vectors responsible for transmitting Dengue which was similar to Mohapatra S and Aslami AN, (39%) and Dhimal M et al., (31%) [18,19]. Sugunadevi G and Dharmaraj A, conducted a similar study in an urban slum area in Coimbatore city in 2013 and observed that only 36% of subjects knew that Dengue was transmitted through mosquito bite . Only 31.4% of the subjects knew that Dengue cannot be transmitted by direct contact similar to Dhimal M et al., (44%), showing that most of the general population still wrongly believe that Dengue is communicable by direct contact .
Most of the respondents in the present study could not correctly identify typical signs and symptoms of Dengue (66.7%) apart from fever, similar to Guha-Sapir D and Schimmer B, (62.6%) and Mohapatra S and Aslami AN, [5,18]. 34.9% of subjects knew that Aedes mosquito was a day biter, while in a study conducted by Malhotra G et al., only 4% knew that Aedes mosquito was a day biter . This discrepancy may be due to the fact that Malhotra G et al., conducted their study among the rural and slum communities of North India, whereas this study was conducted among the general public of Coimbatore . However, majority of people in the present study are still under the misconception that Aedes mosquitoes bite during the night (65.1%). In a study conducted by Mallika CS et al., in urban Thiruchirappali, Tamil Nadu, 23% of college students and 6% of school students knew that Aedes was a day-biter .
In the present study, 40.8% of people knew that Aedes mosquito breeds in clean stagnant water which was consistent with the results obtained by Itrat A et al., (51.1%) . 93.3% of subjects in the study had the correct idea that blood test is necessary to diagnose Dengue while in a study conducted by Malhotra G et al., 73.12% believe that blood test is essential to diagnose Dengue . Approximately, half of the present subjects (49.4%) were still under the misbelief that once a person contracts Dengue he/she becomes immune for the rest of his/her life. Thus, the present study reveals that majority of the study population (74.9%) had relatively average knowledge about Dengue which was similar to results obtained by Mohapatra S and Aslami AN, . This warrants the need for more aggressive public awareness programmes about Dengue in Coimbatore.
The mean knowledge score of subjects who had studied till class 10th was 9.71 whereas the mean knowledge score of subjects with educational qualification above class 10th was 10.64. The difference in mean knowledge scores was statistically significant with a p-value of 0.014. In a study conducted by Chellaiyan VG et al., 51.65% of subjects who had studied above class 10th were aware of the breeding sites and biting habits of Aedes mosquitoes; whereas only 20.34% of subjects with educational qualification below class 10th were aware of the same . This difference was found to be statistically significant (p-value≤0.001) which is consistent with the present study. Itrat A et al., observed that 29.7% of subjects with education below class 10th and 70.3% of subjects with education above class 10th had average knowledge about Dengue ; whereas, in the present study, 67.5% of subjects with education below class 10th and 79% of subjects with education above class 10th had average knowledge about Dengue.
The source of information about Dengue was TV/Radio for 38% of the subjects which was similar to the results obtained by Binsaeed AA et al., (44.5%) and 28.4% relied on newspapers for their information similar to Matta S et al., (24.2%) [21,22]. 46.67% of the present respondents believe that the Government was responsible for controlling mosquito-borne diseases which was in concordance with the results obtained by Valantine B et al., (49%) . Hospitalisation was necessary to treat Dengue according to 90.59% of our subjects which was similar to the results obtained by Valentine B et al., (81%)  and Tamilarasi R et al., (83.13%) . 62.93% of subjects who had studied till class 10th and 76.13% of subjects with educational qualification above class 10th were under the impression that improper sanitation was responsible for Coimbatore being endemic for Dengue.
In the present study, 46.15% of subjects who had studied below class 10th and 31.2% of subjects who had studied above class 10th reported TV/radio to be their source of information regarding Dengue. However, in a study conducted by Valantine B et al., 57.9% of illiterates, 64.1% of subjects with schooling and 77.4% of graduates considered TV/radio to be their major source of information . In the present study, 89.7% of subjects below class 10th and 91.3% of subjects above class 10th believed that hospital care is necessary to treat Dengue which was similar to results obtained by Valantine B et al., (57.9% of illiterates, 84.4% of subjects with schooling and 81.1% of graduates) .
Mosquito nets were used to prevent Dengue by 15.69% of the present subjects which was similar to the results obtained by Acharya A et al., (26.6%) and Chellaiyan VG et al., (14.7%) [7,9]. A 50.98% of the present respondents disposed of stagnant water as a means to prevent Dengue similar to the results obtained by Acharya A et al., (46.5%) . Tamilarasi R et al., conducted a study in Chennai and found that 80.66% of their study population practised disposal of stagnant water to prevent Dengue . A 63.92% of the present subjects had the practice of covering their water containers which was similar to the results obtained by Binsaeed AA et al., (68.6%) . Mosquito repellants were used by 19.21% of the present subjects which was consistent with the results obtained by Itrat A et al., (22.1%) .
In a study conducted by Valantine B et al., 63.1% of illiterates, 70.3% of subjects with schooling and 86.8% of graduates used mosquito nets to prevent Dengue . In the same study, it was observed that 68.4% of illiterates, 58.6% of subjects with schooling and 67.9% of graduates used mosquito coils and repellants as a preventive measure for Dengue. This differed from the results of the present study where only 13.7% of subjects who had studied below class 10th and 17.28% of subjects with educational qualification above class 10th used mosquito nets to prevent Dengue. Similarly, a higher proportion of subjects in the study conducted by Valantine B et al., (94.7% of illiterates, 96.1% of subjects with schooling and 96.2% of graduates) had the practice of keeping their water containers covered compared to the present study (64.75% of subjects who had studied below class 10th and 62.9% of subjects with educational qualification above class 10th) .
A similar study done by Varun KT et al., in the fever clinic of Government Medical College and ESI Hospital among 270 subjects in Coimbatore, showed that even though majority of participants knew about Dengue (94.1%), only half of them identified symptoms correctly (53.7%) and only one third had correct knowledge of breeding habitats of Aedes mosquitoes (30.4%) . They found that younger age group persons (<30 years) and participants with higher education were more aware of Aedes mosquito habits (55.7% and 81.9% respectively) and mosquito preventive measures (72.7% and 71% respectively). Their findings were consistent with the present results.
Currently, numerous programmes are being implemented by the National Vector Borne Disease Control Programme (NVBDCP) to bring awareness to the general population and for the early diagnosis and treatment of Dengue. Under NVBDCP, long-term action plan was implemented on January 2007 which includes facilities for early case management and case reporting, integrated vector management and supporting interventions. Fever alert surveillance, establishment of sentinel surveillance sites with lab support, strengthening of referral services and epidemic preparedness are some of the interventions for early case reporting and management. Integrated vector management includes larval surveys, anti-larval measures (larvivorous fish, source reduction, chemical larvicide) and anti-adult measures (indoor spraying with pyrethrum, fogging, personal protection, insecticide-treated bed nets and repellants). In addition to these, Human Resource Development, Behaviour Change Communication and inter sectoral convergence are also a part of the Long Term Action Plan .
The study was conducted in three public health care centres in Coimbatore and therefore the study population may not be representative of the general population of Coimbatore and the baseline data collected was not complete. The present study period was one month which made it possible to conduct the study only among 300 subjects. Though the authors were able to give health education to the subjects after completion of the questionnaire, authors were not able to follow-up its impact on their knowledge of Dengue. Authors also did not perform household surveys to personally observe the preventive measures practised by the subjects. Thus, further studies with larger sample size are required to substantiate the results.
To conclude, the majority of the subjects had an average knowledge of Dengue and subjects with higher educational qualification were found to have better knowledge about Dengue. Thus, measures to improve the community participation in Dengue prevention control and management has to be reinforced periodically through health education campaigns, mass media and creating awareness at the individual level.*=statistically significant (<0.05)