Seroprevalence of leptospira serovars among rice farmers in mianeh

Sanaz Alioghli,1 Amir ganjkhanlu,2,* Mahdi bayrami,3 Somayeh shekari,4 Milad feizollahi,5 Danial bajgiran,6

1. Department of Biology, University of Mohaghegh Ardabili, Ardabil, Iran.
2. faculty of veterinary medicine, Azad university of Tabriz, Tabriz, Iran
3. Department of Biology, University of Mohaghegh Ardabili, Ardabil, Iran.
4. Department of animal science, faculty of natural science, university of Tabriz, Tabriz, Iran
5. Department of Biology, University of Mohaghegh Ardabili, Ardabil, Iran.
6. Department of Biology, University of Mohaghegh Ardabili, Ardabil, Iran.



Leptospirosis is a zoonotic disease of global importance.1 in recent years, endemic and epidemic severe pulmonary haemorrhage has increasingly become recognised as an important manifestation of leptospiral infection.2–5. it is a direct zoonotic disease caused by spirochetes belonging to different pathogenic species of the genus leptospira. large number of animals acts as carriers or vectors. human infection results from accidental contact with carrier animals or environment contaminated with leptospires. the primary source of leptospires is the excretor animal, from whose renal tubules leptospires are excreted into the environment with the animal urine. majority of leptospiral infections are either sub clinical or result in very mild illness and recover without any complications. however, a small proportion develops various complications due to involvement of multiple organ systems. in such patients, the clinical presentation depends upon the predominant organs involved and the case fatality ratio could be about 40% or more. the aim of this study is to undertake a seroprevalence survey to estimate the distribution of infection by leptospira spp. serovars in farmers regionally in mianeh.


On summer 2017, 100 farmers were selected randomly from four regions from mianeh and blood samples were taken from them. along with that, age was also recorded. samples were sent to the laboratory alongside the dry ice to separate their serum. serum was stored frozen until analysed using the microscopic agglutination test (mat).


In the study, 100 farmers were sampled, 12/100 (12%) were seropositive. among the 12 positive samples, 7, 3 and 2 samples were positive to serovars; grippotyphosa, canicola and pomona respectively. none of the seropositives were infected with other leptospira serovars. also, the highest incidence was in men over 50 years and the lowest incidence was in people under the10 years.


In conclusion, rice farmers compared to the other residents in the rural areas are more significantly infected with leptospirosis due to traditional agricultural methods, in the mianeh region and infection is highly affected by gender (male) and age. the most important source for exposure to this infection is water sources; rivers or brooks are highly suspected to be infected with leptospira species. another source of infection is farm houses where rodents and rats are frequently observed. therefore, health and safety measures must be developed to control and prevention of this disease. also, by using mechanized agricultural methods, the prevalence of this disease in the region is largely prevented.


Seroprevalence, leptospirosis, rice farmers, miane