Field Application of NIR Spectroscopy for the Discrimination of the Biomphalaria Species That Are Intermediate Hosts of Schistosoma mansoni in Brazil

Area of Science:

• Biophysics
• Analytical Chemistry
• Medical Malacology

Background:

• Accurate identification of snail intermediate hosts for Schistosoma mansoni is crucial for epidemiological control in Brazil.
• Three Biomphalaria species (B. glabrata, B. straminea, B. tenagophila) are important hosts, each with unique biological characteristics.
• Existing identification methods may not be sufficient for rapid, on-site differentiation.

Purpose of the Study:

• To develop and validate a chemometric model using Near Infrared Spectroscopy (NIRS) for classifying three Biomphalaria snail species.
• To assess the technique's ability for both interspecific (between species) and intraspecific (within species) classification.
• To investigate chemical and metabolic variations between field and laboratory populations.

Main Methods:

• Near Infrared Spectroscopy (NIRS) was employed to acquire chemical profiles from 271 Biomphalaria snails.
• Samples included three species (B. glabrata, B. straminea, B. tenagophila) from field and laboratory populations in Rio de Janeiro.
• Chemometric analysis was performed using Unscrambler® software to build classification models.

Main Results:

• The NIRS-based chemometric model achieved high accuracy rates for intraspecific classification: 85.0% for B. glabrata, 77.5% for B. straminea, and 72.5% for B. tenagophila.
• Interspecific differentiation yielded hit rates of 75% for field populations and 80% for laboratory populations.
• Significant chemical and metabolic differences were observed between field and laboratory populations of the same species, indicating environmental influence on chemical phenotype.

Conclusions:

• NIRS is a rapid, non-destructive, and effective tool for the systematic discrimination of Biomphalaria snail species.
• The technique can differentiate between species and populations, offering valuable insights into their chemical phenotypes and metabolic profiles.
• NIRS shows significant potential for application in medical malacology for epidemiological surveillance and control of schistosomiasis transmission.