# SHERLOCK4AAT, a new molecular method for highly sensitive and specific detection of animal African trypanosomes

Aïssata Camara, Elena Perez Anton, Roger Junior Eloiflin, Annick

Dujeancourt Henry, Martial Kassi N’Djetchi, Mathurin Koffi, Dramane Kaba, Vincent Jamonneau, Dansy Camara, Moïse Kagbadouno, et al.

► To cite this version:

Aïssata Camara, Elena Perez Anton, Roger Junior Eloiflin, Annick Dujeancourt Henry, Martial Kassi N’Djetchi, et al.. SHERLOCK4AAT, a new molecular method for highly sensitive and specific detection of animal African trypanosomes. SHERLOCK4AAT, a new molecular method for highly sensitive and specific detection of animal African trypanosomes, Oct 2024, Conakry, Guinea. [hal-05415549](https://hal.science/hal-05415549v1)

HAL Id: hal-05415549

https://hal.science/hal-05415549v1

Submitted on 15 Dec 2025

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Distributed under a Creative Commons Attribution 4.0 International License
6th JOINT HAT PLATFORM-EANETT SCIENTIFIC
MEETING

SHERLOCK4AAT, a new molecular method for highly sensitive
and specific detection of animal African trypanosomes

Aïssata Camara, Elena Perez Anton, Roger-Junior Eloiflin, Annick Dujeancourt-Henry, Martial Kassi N'Djetchi, Mathurin Koffi, Dramane Kaba, Vincent Jamonneau, Dansy Camara, Moïse Kagbadouno, Mamadou Camara, Jean-Mathieu Bart, Lucy Glover and Brice Rotureau

<figure><img src="image_2.png" /></figure>

INSTITUT
PASTEUR
de Guinée

PASTEUR NETWORK

<figure><img src="image_3.png" /></figure>

UJLoG

UNIVERSITE
JEAN LOROUGNON GUEDE

<figure><img src="image_4.png" /></figure>

Intertryp

dans les maladies tropicales négligées dues aux trypanosomatidés

Interactions hôtes-vecteurs
-parasites-environnement

<figure><img src="image_5.png" /></figure>

<figure><img src="image_6.png" /></figure>

INSTITUT
PASTEUR

<figure><img src="image_7.png" /></figure>

INSTITUT PIERRE RICHET

<figure><img src="image_8.png" /></figure>

SHERLOCK platform
for trypanosomatid Parasites detection.

Agence Nationale de la Recherche
ANR
African trypanosomiases

HAT

* 2 species: *Tb. gambiense*
94% + *Tb. rhodesiense* 6%

* < 1000 new cases / year since 2018

* gHAT elimination target

AAT

<figure><img src="image_9.png" /></figure>

* >7 species

* 50M cattle at risk

* 3M cattle deaths

* US$ 4 billion/year

* AAT control target

→ New sensitive and specific detection methods required for diagnosis and epidemiological surveillance
SHERLOCK: Specific High-sensitivity Enzymatic Reporter unLOCKing

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# A SHERLOCK toolbox for detecting animal trypanosomes

## Trypanosome diversity

<figure><img src="image_11.png" /></figure>

## Targeting strategy

<figure><img src="image_12.png" /></figure>
# Targets

## 18S rRNA

5'

T. congolense-specific

Amplicon: 116 - 246

<figure><img src="image_13.png" /></figure>

T. theileri-specific

Amplicon: 1014 - 1158

<figure><img src="image_14.png" /></figure>

T. simiae-specific

Amplicon: 1246 - 1346

<figure><img src="image_15.png" /></figure>

Pan-Trypanozoon

Amplicon: 1318 - 1433

<figure><img src="image_16.png" /></figure>

Pan-Trypanosomatid

Amplicon: 1535 - 1672

<figure><img src="image_17.png" /></figure>

## IFX

5'

T. vivax-specific

Amplicon: 686 - 793

<figure><img src="image_18.png" /></figure>

1824

## GAPDH

5'

T. suis-specific

Amplicon: 389 - 528

<figure><img src="image_19.png" /></figure>
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## Limits of detection:

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0.25 - 0.05 pg/µL

<figure><img src="image_23.png" /></figure>

0.025 - 0.005 pg/µL
Application to epidemiological surveillance

<figure><img src="image_24.png" /><figcaption>JM Bart</figcaption></figure>

<figure><img src="image_25.png" /><figcaption>JM Bart</figcaption></figure>

* Importance of domestic pigs as reservoirs of human trypanosomes?

* Prevalence of animal trypanosomes in domestic pigs?

<figure><img src="image_26.png" /></figure>
## Ancient gHAT foci
Guinea

<figure><img src="image_27.png" /></figure>

200 farm pigs

<figure><img src="image_28.png" /></figure>

## Blood sampling

<figure><img src="image_29.png" /></figure>

JM Bart

## Hypo-endemic gHAT foci
Côte d'Ivoire

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230 free-ranging pigs

<figure><img src="image_31.png" /></figure>
# Application to epidemiological surveillance

52% positive in parasitological tests (n=230)

<figure><img src="image_32.png" /></figure>
Application to epidemiological surveillance

<figure><img src="image_33.png" /></figure>
**Prevalence of animal trypanosomes in domestic pigs?**

* High proportions of trypanosome infections

* Similar proportions of trypanosome infections across two geographically and epidemiologically distinct foci

* Higher prevalence of *T. congolense* circulating in Cote d'Ivoire

**Importance of domestic pigs as reservoirs of human trypanosomes?**

* Detection of one *T.b. gambiense* infection in both foci

* *T.b. gambiense* is likely not eradicated in ancient and hypo-endemic foci, and pigs could represent reservoir for gHAT parasites
# Take-home message

* Versatility of the SHERLOCK technology to adapt to different targets and contexts

* High sensitivity and specificity of the SHERLOCK4AAT toolbox for molecular epidemiological surveillance

## 1. Developpement

<figure><img src="image_34.png" /></figure>

## 2. Implementation

<figure><img src="image_35.png" /></figure>
# SHERLOCK4AAT, a new molecular method for highly sensitive and specific detection of animal African trypanosomes

Aïssata Camara, Elena Perez Anton, Roger-Junior Eloiflin, Annick Dujeancourt-Henry, Martial Kassi N'Djetchi, Mathurin Koffi, Dramane Kaba, Vincent Jamonneau, Dansy Camara, Moïse Kagbadouno, Mamadou Camara, Jean-Mathieu Bart, Lucy Glover and Brice Rotureau

<figure><img src="image_36.png" /></figure>

INSTITUT
PASTEUR
de Guinée

PASTEUR NETWORK

<figure><img src="image_37.png" /></figure>

UJLoG

UNIVERSITE
JEAN LOROUGNON GUEDE

<figure><img src="image_38.png" /></figure>

Intertryp

dans les maladies tropicales négligées dues aux trypanosomatidés

Interactions hôtes-vecteurs
-parasites-environnement

<figure><img src="image_39.png" /></figure>

<figure><img src="image_40.png" /></figure>

INSTITUT
PASTEUR

<figure><img src="image_41.png" /></figure>

INSTITUT PIERRE RICHET

<figure><img src="image_42.png" /></figure>

SHERLOCK platform
for trypanosomatid Parasites detection.

Agence Nationale de la Recherche
ANR