EPIDEMIOLOGY OF LEPTOSPIROSIS & CONTROL MEASURES. Dr.I.Selvaraj. Leptospirosis is an acute anthropo-zoonotic infection It occurs in tropical, subtropical and temperate zones.
Locations where the infection is commonplace, caused by high rainfall, close human contact with livestock or wild animals, poor sanitation or workplace exposure (rice farming, etc). Example countries in class L2 are India, Central America and certain areas of the Pacific Rim.
L1 - General
Locations where the infection is at the international average of 0.05 cases per 100,000, and infection is usually the result of accidental exposure through wild rats, livestock or direct contact with water through leisure or occupation. Example countries in class L1 are North America, Europe, Australia and the former Soviet territories.
In 1905, Chowdry presented 585 cases of the disease in the Andaman islands, calling it "malaria with jaundice".
In the Andamans, this disease was also called as "Andaman haemorrhagic fever" with a predominance of haemorrhagic signs.
In Kerala, it was the same type as seen in the Andamans.
In Chennai city, the most severe form was jaundice and a haemorrhagic type.
Of late, eye disorders as late complications of leptospirosis have been recorded in Madurai.
Cardiac arrhythmias in Mysore are the latest reports on the manifestations of the disease.
1. Anicteric leptospirosis or self-limited illness (85% to 90% of the cases)
2. Icteric leptospirosisor weil’s syndrome (5% to 10% )
A microscopic view of LeptospiraI bacteria stained apple green with a fluorescent dye (from the CDC’s Public Health Image Library)
Wild and domestic animals rodents, livestock (cattle, horses, sheep, goats, swine), canines, and wild mammals are the reservoir for leptospirosis. Many animals have prolonged leptospiruria without suffering from the disease themselves.
Humans with leptospirosis usually excrete the organism in the urine for 4-6 weeks and occasionally for as long as 18 weeks.
Cases are seen sporadically throughout the year. But an outbreak occurs during the rainy season because of widespread contamination by infected rodent urine in flood water.
Detection of antibodies to leptospira:
All the people involved in high-risk activities should wear protective clothing and need to adopt a reasonable standard of hygiene. Impervious knee-high boots, aprons, gloves, face masks or eye protection should be used wherever indicated.Immunization of high risk groups (USSR, CHINA,ITALY)
Chemo prophylaxis:Doxycycline can prevent leptospirosis, if given before and during exposure.
The International Leptospirosis Society (ILS) was formed in 1994 to promote knowledge on leptospirosis through the organisation of regional and global leptospirosis meetings.