Rice-Field Leptospirosis in Turkey. A Serologic Survey

View More View Less
  • Fourth Epidemiological Flight, U. S. Air Force, Izmir Turkey and Division of Veterinary Medicine, Walter Reed Army Institute of Research, Walter Reed Army Medical Center, Washington, D. C.

Summary

A serologic survey for leptospiral agglutinins was conducted on serums from 240 human beings, 914 cattle, 115 horses, 109 goats, 50 donkeys and 49 sheep, located in three rice-raising areas and one adjacent livestock breeding area in south central Turkey. Employing a very conservative test criterion for a significant serologic reaction, the percentages of positives in the various hosts were the following: man—9.6, cattle—59.0, goats—69.3, sheep—22.4, horses—47.8 and donkeys—58.0. Most of the predominant serologically positive reactions in human beings, goats and sheep were elicited with L. grippotyphosa antigen, a lesser number with screening antigens in the hebdomadis group. In bovine serums, however, in addition to the presence of agglutinins against L. grippotyphosa, a large proportion of seropositive reactions was primarily against antigens of the hebdomadis group, notably L. sejroe. The highest percentage of bovine seropositives was derived from the non-rice-raising area and most of the animals were reactors against the hebdomadis group antigens. Equine positive serums showed a large proportion of predominant titers against L. grippotyphosa and hebdomadis group antigens and also against L. autumnalis; however, a greater variety and multiplicity of agglutinins were observed in these serums.

The titers of human seropositives were either 1:100 or 1:400; however, titers observed in animal serums ranged up to 1:25,600. It was apparent from the distribution of titers that recent episodes of infection in livestock had occurred or were in progress in some of the villages at the time serums were collected.

Differences in prevalence ratios attributed to sex were not evident from the available data for any of the species tested. Generally, the percentage of positives was lowest in youngest age groups of the various species; however, a stepwise increase in the percentage positive in successively older groups was not noted.

These findings indicate that the rice-field regions of south central Turkey are epidemic or endemic foci of leptospiral infections in man and domestic animals, and that most of these infections are presumably caused by L. grippotyphosa and a member of the hebdomadis group, possibly L. sejroe.

Author Notes

Major, USAF (VC), Veterinarian formerly assigned to Fourth Epidemiological Flight, U. S. Air Force, Izmir Turkey. Present address—6550th U. S. Air Force Hospital, Patrick Air Force Base, Florida.

Division of Veterinary Medicine, Walter Reed Army Institute of Research, Walter Reed Army Medical Center, Washington 12, D. C.

Peudik Bacteriological Institute, Istanbul, Turkey.

Save