In this slide i have discussed all the conventional tools to diagnose parasitic infections and also included all the new diagnostic advances have came to deep tech world.
2. ACKNOWLEDGEMENT
First and foremost, I would like to thank for,
Dr.Subhash Chandra Parija, Vice Chancellor, Shri Balaji
Vidyapeeth from Puducherry given such a knowlegable
Lecture in online series based on “Basic Principles of
Laboratory Diagnosis of Parasitic Infection”.
My special thanks gives to Dr. R. Sujatha, Professor and
Head of the Department, for giving me such a
opportunity to present it.
I m also thankful to all my Teachers of the Microbiology
department.
3. Introduction
In 2023, the World Health
Organization (WHO) reported
an estimated 137,000 deaths,
caused by foodborne parasitic
diseases.
Vector-borne diseases caused
by parasites every year, with
400,000 being caused by
malaria alone.
4. Amoebiasis is an intestinal parasitosis
caused by the protozoan Entamoeba
histolytica that represents the third
leading cause of mortality due to
parasitosis.
7. Gross / Macroscopic Examination
ď‚— Consistency
ď‚— Color
ď‚— Odor
ď‚— Presence of blood
ď‚— Presence of mucus
ď‚— Presence of adult worms or segments
of tapeworm
11. 3.Staining techniques
Iodine mount
For Nuclear details of cysts, helminthic eggs and Larvae
Advantage- Better visualization
- Species identification
Disadvantages - Iodine immobilizes and kills parasite
- Lowe sensitivity (25-60%)
- can not appreciate for
Motility of the protozoan trophozoites &
Helminthic larvae
12. Types of Iodine stains
 Lugol’s Iodine
 D’Antoni iodine
 Dobeil’s iodine
2. Permanent stained smear
(Accurate diagnosis, stain for internal structure)
1. Iron hematoxylin stain
2. Trichrome stain
3. Modified acid fast stain (Cryptosporidium,
Cyclospora & isospora belli)
13. 4. Scotch tape technique
(Use For diagnosis of pinworm) – Enterobius
vermicularis
5. Skin scrapping technique
(Use for diagnosis of Ectoparasites)- e.g.
Sacroptes, Otodectes.
14. CULTURE
Culture techniques Uses
Harada Mori
technique
Strongyloides
larvae
Baermann
technique
Identification of
3rd stage Larvae
( based on active
movement of
larvae)
Charcoal
culture tech
Infective stage of
Strongyloides
larvae
Agar plate
culture tech
S. Stercoralis
and Hookworm
15. Fig - Timeline of technologies for medical parasite and arthropod
diagnoses. Microscopy has been applied for pathogen and insect
identifications for several centuries. To improve detection efficacy, a
range of techniques have emerged. They encompass artificial
intelligence, ELISA, PCR, geometric morphometrics, and DNA barcoding
technique
16. Immunological Examination
ELISA
IMMUNOBLOT ASSAY
Use for Detection of
Ag/Ab of Ameobiasis,
Chagas’ disease,
Toxoplasmosis,
Schistosomiasis and
Lymphatic filariasis
Useful for Diagnosis
of schistosomiasis,
strongylodiasis, and
hydatid disease
Rapid card test
e.g.- Malaria parasite
17. Advantages of Antigen detection tests
ď‚— Detect circulating parasite Ag/Ab in serum, urine,
genital specimens or feces
ď‚— Detect acute/recent infection
ď‚— Monitor response to treatment
ď‚— Useful when microscopy is negative.
LIMITATIONS
-high cross-reactivity,
-time consuming,
-labor intensive,
-unable to detect low-level antibodies
-costly reagents
Higher sensitivity
(80 to 94%)
Specificity
(94 to 100%)
than microscopy
and culture
19. Molecular Biology
1. DNA Probe
Radiolabelled neucleotide sequences
Complementary to a part of the parasite
(clinical samples)
Use for P. falciparam, W. bancrofti
20. 2. Polymerase Chain Reaction (PCR)
The Operational framework in molecular diagnostics
21. Most useful for targeting 16S- rRNA gene for
differential detection of all the three morphologically
similar forms of
E. histolytica, E. moshkovskii and E. dispar
simultaneously in stool samples
22. Entamoeba
ď‚— Pseudopod forming protozoan
parasites
ď‚— Possess nucleated cysts(larger-
8neuclei)
ď‚— 7 different species (E. histolytica,
E. coli, E. hartmanni, E. polecki,
E. dispar, E. moshkovskii and E.
bangladeshi)-Human Intestine
 E. gingivalis – Oral cavity
commensal
ď‚— SOI-Contaminated Food and
water
23. Most widely used PCR marker for taxonomic
differentiation between E. histolytica, E. dispar
and E. moshkovskii.
24. Molecular diagnosis of amoebiasis in stool sample
Fig. Complete Process of Nested multiplex PCR for differential
detection of Entameoba
STOOL
SAMPLE
28. ď‚— Running cost (consumables & equipment)
ď‚— Requirement of laboratory setup
ď‚— Unavailabilty of detection kits for many parasites
ď‚— Trained technical manpower
These are acting as the
impediment for the bench-to-field
of the technology especially for
the lower and Middle Income countries
29. Move to Deep Technology Era of Parasitic
Diagnosis
30. What is DEEP TECHNOLOGY
- Those techniques whose working model is based on
high tech innovation in scientific advances
-Come up with innovative solutions
-Approaches to adressing big societal challenges
31. What Deep Tech will offer ?
ď‚— Maximum sensitivity
ď‚— Maximum specificity
ď‚— Portability
ď‚— Scalability
ď‚— User friendly
ď‚— Multiple parasitic detection
ď‚— Parasite stages detection
ď‚— focusing on publicly available microscopic image
datasets of protozoan parasites.
33. IIT Kharagpur faculty develops smartphone app for
Malaria in 2015
Malaria screener
First Smartphone-based system
Automated malaria light microscopy
Screen thin and thick smears
Fig- System Setup for Malaria Screener.
37. ď‚— Dataset contains four species of Malaria
parasites: Falciparum, Malariae, Ovale, Vivax
ď‚— Six types of protozoan parasites
ď‚— (Plasmodium, Toxoplasma, Babesia, Leishmania,
Trypanosome, Trichomonad)
ď‚— Host cells (RBCs and Leukocyte)
TARGETS
38. Not only Parasite, the Deep Tech also enable
identification of stages
Sci
Rep 11,16919
39. Why only one Parasite
Lets detect all in sample
VETSCAN
IMAGYST
ParasiteVectors 13,346 (2020)
40. ď‚— Requires reference data sets
from database
ď‚— Still limited to some parasites
ď‚— Need for re-imagination
ď‚— Need to push science
boundaries
ď‚— Difficulties in scaling up
ď‚— Difficulties in accessing
funding
41. Conclusion
Microscopy with poor sensitivity and
Serological diagnosis have also several limitations……BUT
Molecular studies is useful tool for understanding pathogenesis, help
developing novel treatment strategies !
Deep Tech innovations offers disruptive solutions
Zero interpretation biases, Detect even single
parasite