Despite possessing a highly-satisfactory level of overall knowledge and attitudes on leptospirosis preventive measures, local farmers have not practised leptospirosis preventive measures adequately.
These findings were made in an original research article on the ‘Knowledge, attitudes and practises of preventive measures in leptospirosis among farmers in a lower-middle income country: Evidence from a divisional health area of Sri Lanka’ which was authored by C. Dhanasinghe (attached to the Postgraduate Institute of Medicine) and D. Gamage (attached to the Health Ministry's Epidemiology Unit) and published in the Journal of the College of Community Physicians of Sri Lanka's 30th Volume's First Issue in April of this year.
Leptospirosis is a zoonotic (an infectious disease that is transmitted between species from animals to humans or from humans to animals) bacterial infection caused by the pathogenic (disease causing) spirochete (a group of spiral shaped bacteria) of the gene Leptospira. The common reservoir hosts are rats, rodents, farm animals like cattle and pigs, and dogs. The infected hosts excrete spirochetes with the urine, causing contamination of soil and water sources. Spirochetes, as the Epidemiology Unit's ‘National Guidelines on the Management of Leptospirosis’ notes, survive up to 14 days in the external environment while some virulent forms can do so for months.
This is, as elaborated in E. Bierque, R. Thibeaux, D. Girault, M.E. Soupé-Gilbert and C. Goarant's ‘A systematic review of leptospira in water and soil environments’, the reason behind large outbreaks following floods due to the bacteria being released into the water. Leptospirosis human infection can occur most commonly through the mucosal surfaces and breached skin when exposed to contaminated soil or water. Consequently, farmers, mine workers, flood victims and urban slum dwellers are at a higher risk of developing leptospirosis compared to the general public.
The highest leptospirosis morbidity is, as mentioned in F. Costa, J.E. Hagan, J. Calcagno, M. Kane, P. Torgerson, M.S. Martinez-Silveira, B. Albela-Ridder and I.K. Albert's ‘Global morbidity and mortality of leptospirosis: A systematic review’, reported in the South Asian and South-East Asian regions. In Sri Lanka, the annual leptospirosis case load was estimated to be 10,423 with a cumulative incidence of 52.1 per 100,000 persons between 2008-2015 (J. Warnasekara, I. Koralegedara and S. Agampodi's ‘Estimating the burden of leptospirosis in Sri Lanka: A systematic review’).
The key primary preventive strategies for leptospirosis include, per R.A. Hartskeerl, M. Collares-Pereira and W.A. Ellis's ‘Emergence, control and re-emerging leptospirosis: Dynamics of infection in the changing world’, rodent control, personal hygiene, personal protective equipment (PPE) to prevent contact, and pre-exposure and post-exposure chemoprophylaxis (the administration of a medication for the purpose of preventing disease or infection). One of the preventive strategies recommended only for well recognised high-risk groups in Sri Lanka is the administration of the doxycycline prophylaxis, which is given as a weekly dose during the paddy cultivation period for farmers as well as during flood situations for victims.
Despite the available guidelines and circulars on the prevention and management of leptospirosis, there were 8,323 total notified cases in 2020, of which the highest number (1,532) was reported from the Ratnapura District along with 19 deaths (Ratnapura has the highest leptospirosis burden in Sri Lanka). The knowledge level and attitudes are important prerequisites that influence the behaviour of an individual. In order to achieve control by adhering to the preventive practices, knowledge related and attitudinal deficiencies should be identified and addressed by the health authorities.
Dhanasinghe et al. conducted a community based cross sectional study among farmers in the Pelmadulla Medical Officer of Health (MOH) area in the Ratnapura District. The registered principal farmers of farming families, who had engaged in farming for a minimum of two years in Pelmadulla were taken as the study population. Farmers who defaulted from paddy farming during the previous two years were excluded. The farmers who were registered under a farmer community in the relevant Agricultural Research Assistant Divisions were taken as a cluster. Data was collected during January, 2022.
Results
In total, 426 subjects were recruited with a response rate of 97.7%.
Knowledge on preventive measures in leptospirosis in the study participants was assessed thus: leptospirosis is transmitted by rats; leptospirosis is transmitted only by rats; water gets contaminated by the infected animal’s urine; the stagnation of water is a risk factor for infection transmission; a person can get the infection through damaged skin; touching the eyes, nose and mouth with contaminated hands cannot result in leptospirosis infection; drinking water from natural water sources without boiling can result in infection; rodent control measures are useful in reducing leptospirosis transmission; proper waste disposal is important in leptospirosis prevention; and taking the doxycycline medication during the paddy season will protect from getting the infection. With regards to knowledge on leptospirosis, transmission by rats was correctly answered by 94.1%, while the majority knew that water sources can be contaminated by infected rodent urine (93.7%), that a person can get the infection through damaged skin while touching the eyes, nose and mouth with contaminated hands can result in infection (94.6%), that rodent control measures are useful in reducing leptospirosis transmission (87.3%), that proper waste disposal is important in leptospirosis prevention (91.6%), and that taking doxycycline medication during the paddy season protects them from getting the infection (89.4%). The total knowledge scores ranged from two to 10 with a mean of 7.88. The majority (349/81.9%) had satisfactory knowledge of leptospirosis preventive measures.
Attitudes on preventive measures in leptospirosis in the study participants were assessed thus: I think that prophylaxis is effective; I think that leptospirosis needs more control and prevention than currently practised; living rats in and around the paddy fields help in nurturing the soil; I think that a proper garbage disposal system is essential for rat control; I think that wearing proper gloves and boots when working in the field is necessary for controlling the transmission of leptospirosis; I think that covering wounds is necessary for controlling the transmission of leptospirosis; drinking water is not a source of infection, and so, boiling is not a must; I should not touch my nose and eyes with contaminated hands as I can get leptospirosis; I have already got leptospirosis once, so, I am not at risk again; and I am not bothered about getting leptospirosis as I am working in the paddy fields for a long duration.
With regards to attitudes towards preventive practises, 77% believed that the doxycycline chemoprophylaxis is effective against leptospirosis, 94.1% believed that there is a need for a proper garbage disposal system for rat control, and 85% believed that wearing proper gloves and boots when working in the field is protective against the infection. The total attitude scores ranged from two to 10 with a mean of 7.54 and the majority (310/72.8%) had good attitudes toward leptospirosis preventive measures.
The practise of preventive measures in leptospirosis in the study participants was assessed thus: I wear boots and gloves when working in the fields; I cover open wounds before working in the field; I take the doxycycline prophylaxis properly; I use only cooled boiled water for drinking; I use traps and bait as a form of rodent control; I have patched all rat holes prior to commencing cultivation; I have a good garbage disposal system; I have established a proper water drainage system in my paddy field to prevent water stagnation; I practise soil tillage to get good exposure to sunlight; and I practise betel chewing while working without washing hands with soap and water. With regards to preventive practices in leptospirosis, boots and gloves were always used only by 8% and often used by 14.3%, while half of the participants always covered open wounds before working in the field. Only 55.7% always used the doxycycline prophylaxis properly and only 27% used cooled boiled water for drinking. However, 70.7% always patched all rat holes before starting cultivation, while 89.6% had a good garbage disposal system and 85.7% always established a proper water drainage system in the paddy fields to prevent water stagnation. The total practice scores ranged from one to 20 with a mean of 12.03. Only 70/16.4% had good preventive measures.
Farmers who had good knowledge on preventive practices had six times better compliance with such preventive practices compared to farmers who did not (19.2% versus 3.9%).
Discussion
The study findings show that the sample had satisfactory knowledge and attitudes on leptospirosis preventive measures but had deficiencies in the preventive practises. It could be due to other influencing factors which act as barriers such as the educational level, the perceived risk and the perceived susceptibility due to past experience, and the affordability, availability and accessibility of the protective facilities.
A total of 81.9% of the sample had satisfactory knowledge of leptospirosis preventive measures. The current evidence of high knowledge scores shown among farmers was supported by a survey (S.B. Agampodi, T.C. Agampodi, E. Thalagala, S. Perera, S. Chandraratne and S. Fernando's ‘Do people know adequately about leptospirosis? A knowledge assessment survey in a post-outbreak situation in Sri Lanka’) that suggested that the knowledge among farmers on certain aspects of leptospirosis was significantly higher compared to the general public. This improvement in knowledge may be a result of continuous awareness raising programmes conducted by the Health Ministry targeting high risk populations. However, the risk of contracting the disease through consuming contaminated drinking water without boiling and the direct touching of the mucosal membranes need to be addressed further. Overall knowledge is satisfactory.
A total of 72.8% of the current study sample had good attitudes towards leptospirosis preventive measures with a mean attitude score of 7.54. Over 80% of the participants believe that leptospirosis needs more control and prevention than is currently practised. The majority (more than 70%) had a satisfactory attitude towards the use of PPE during the work in paddy fields. A total of 94.1% believed that there is a need for a proper garbage disposal system to achieve rat control. This finding is very important as it plays a main role in the health belief related model. It is not only knowledge that affects the decisions of people, but also attitudes and beliefs. Attitudes may have cultural influences, peer related influences and societal influences. Therefore, it may vary from person to person and need individual level interventions such as behavioural change related communication to address any identified deficiencies.
In the current study, the total scores of practises for preventive measures ranged from one to 20 with a mean of 12.03. Only 70/16.4% of the study sample had a good practice score on leptospirosis preventive measures.
However, the knowledge on the possible risk of contracting the disease through consuming contaminated drinking water without boiling and the direct touching of mucosal membranes needs to be addressed. The study further demonstrated the poorer practise of preventive measures compared to knowledge and attitudes. Their usage of PPE and chemoprophylaxis, and rodent control measures were minimal, yet, they had good garbage disposal practices.
The Ministry is placing more emphasis on awareness raising, but, the barriers need to be explored and addressed to improve the preventive practices and to reduce the leptospirosis disease burden in the country.