National Reference Laboratory for Leptospirosis
Head of Laboratory
Dr. Lilani Karunanayake
Consultant Clinical Microbiologist
Eight new reference Leptospira serovars from human and animals have been added from Sri Lanka to the world literature (gem, alice, weerasinghe, ratnapura, ceylonica, jeyaweera, lanka and animal spp.) In 1971, Dr. Nityananda identified many different serotypes and their reservoir hosts in Sri Lanka. The findings suggested the existence of a diversity of serotypes maintained by different maintenance hosts such as rodents, domestic farm animals and dogs [K. Nithyananda et.al.,‘Leptospirosis in Ceylon]. In 1962, a serological survey of occupational groups showed rice field workers, sewer workers, workers in coconut plantations and desiccated coconut mills, sugar cane workers, abattoir workers, fish market workers and river bathers were as at risk of leptospirosis.
Heads of National Reference Laboratory for Leptospirosis
1953 – Dr. K. Nityananda, Consultant Bacteriologist
1970’s – Dr. M. Atapattu, Consultant Microbiologist
2000 – Dr. Philomina Chandrasiri, Consultant Clinical Microbiologist
2003 – Dr. Praneetha Somarathne, Consultant Clinical Microbiologist
2011 to date – Dr. Lilani Karunanayake, Consultant Clinical Microbiologist
Presently available tests:
- Microscopic Agglutination Test (MAT) Pathogenic Panel
- Leptospira detection by qPCR from blood and urine
- Blood culture
- Urine / CSF Microscopy
HUMAN LEPTOSPIROSIS IN SRILANKA
Leptospirosis is a zoonotic bacterial infection caused by pathogenic spirochetes of Leptospira interrogans. It is maintained by chronic renal infection in carrier animals, which excrete leptospira in their urine and contaminate the environment.
Leptospirosis is a notifiable disease in Sri Lanka. It is highly endemic, with an annual incidence rate of >10/100,000 population. There is an increase in case fatality in recent times. In SPHS 41.2%, AKI 32.4% , mayocarditis 52% was seen in leptospirosis patients in Southern Province.
Human Leptospirosis is an acute febrile illness with a wide spectrum of clinical manifestations, ranging from mild to severe disease.
The common circulating serogroup is Tarassovi. The important maintenance hosts in Sri Lanka are cattle, buffalo and rats.
High risk occupations include farmers, labourers, manual workers and men in armed forces.
Common severe diseases include Acute Kidney Injury (AKI), Leptospirosis associated severe pulmonary haemorrhagic syndrome (SPHS), liver involvement, myocarditis and pancreatitis. Other complications noted in our patients are hemiplegia, hepatic encephalopathy, acute quadriplegia, cerebellar signs, Guillain-Barre syndrome, and skin rash. SPHS is now commonly seen in Southern Province.
Source: Karunanayake et.al., Demographic, Clinical and Bacteriological Characteristics of Human Leptospirosis in Sri Lanka: A Retrospective Study. J Bacteriol Mycol – Volume 3 Issue 2 – 2016 ISSN : 2471-0172
Leptospira Diagnostic time-line at NRL
1959 – Complement fixation test and Guinea pig inoculation
1962 -Macro-agglutination test
1970’s – Sapropytic Microscopic Agglutination Test (MAT), blood culture
2014 – Pathogenic Microscopic Agglutination Panel introduced for MAT, Leptospira culture methods revised
2016 – Leptospira detection by qPCR