Surveillance of leptospiral reservoirs in synanthropic rodents using loop-mediated isothermal amplification

Micaela Hamer1, Vanina Saraullo1, Emiliano Muschetto2

  • 1Laboratorio de Leptospirosis. Instituto de Patobiología - IPVET (UEDD INTA-CONICET), Centro de Investigación en Ciencias Veterinarias y Agronómicas (CICVYA), Instituto Nacional de Tecnología Agropecuaria (INTA), Nicolás Repetto y de los Reseros s/n, Hurlingham, Buenos Aires, Argentina.

Insights

Loop-mediated isothermal amplification (LAMP) effectively detects leptospiral DNA in rodent kidneys, showing substantial agreement with PCR. This cost-effective method aids leptospirosis surveillance in resource-limited settings.

Area of Science:

  • Veterinary Medicine
  • Molecular Diagnostics
  • Zoonotic Diseases

Background:

  • Leptospirosis is a significant zoonotic disease with global public health implications.
  • Rodents are primary reservoirs for pathogenic Leptospira spp., facilitating environmental contamination.
  • Accurate diagnostics are crucial for understanding and controlling leptospirosis transmission.

Purpose of the Study:

  • To evaluate the diagnostic efficacy of loop-mediated isothermal amplification (LAMP) for detecting leptospiral DNA in rodent kidney samples.
  • To compare LAMP performance against the established lipL32 PCR assay.
  • To assess LAMP's utility as a diagnostic tool for leptospirosis surveillance.

Main Methods:

  • Rodent kidney samples were analyzed using both loop-mediated isothermal amplification (LAMP) and lipL32 PCR.
  • Leptospiral DNA detection rates were compared between the two molecular diagnostic methods.
  • Statistical analysis, including Cohen's Kappa index, was used to determine agreement.

Main Results:

  • Leptospiral DNA was detected in 9.0% of rodent samples.
  • LAMP demonstrated higher sensitivity, detecting 3.2% more positive samples than PCR alone.
  • A substantial agreement (Cohen's Kappa = 0.77) was observed between LAMP and lipL32 PCR methods.

Conclusions:

  • LAMP is a sensitive, cost-effective molecular diagnostic tool for detecting leptospiral DNA in rodents.
  • The method shows promise for leptospirosis surveillance, particularly in low-resource settings.
  • Further studies incorporating species identification are recommended for comprehensive epidemiological analysis.