Sensitive Detection of Asymptomatic and Symptomatic Malaria with Seven Novel Parasite-Specific LAMP Assays and Translation for Use at Point-of-Care

Malpartida-Cardenas, Kenny; Moser, Nicolas; Ansah, Felix; Pennisi, Ivana; Prah, Diana Ahu; Amoah, Linda Eva; Awandare, Gordon A.; Hafalla, Julius Clemence R.; Cunnington, Aubrey J.; Baum, Jake; Rodríguez-Manzano, Jesús; Georgiou, Pantelis

doi:10.1128/spectrum.05222-22

Cited by 6 publications

(5 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ease of use is a key benefit of the miLab platform. While nucleic acid amplification tests such as PCR and LAMP are more sensitive and simplified protocols for use at point-of-care are increasingly developed, they all require basic laboratory skills to conduct multiple pipetting steps and interpret results [26][27][28]. Training of health center personnel to conduct these steps is a major challenge.…”

Section: Discussionmentioning

confidence: 99%

A digital microscope for the diagnosis of Plasmodium falciparum and Plasmodium vivax, including P. falciparum with hrp2/hrp3 deletion

Ewnetu,

Badu,

Carlier

et al. 2024

PLOS Glob Public Health

View full text Add to dashboard Cite

Sensitive and accurate malaria diagnosis is required for case management to accelerate control efforts. Diagnosis is particularly challenging where multiple Plasmodium species are endemic, and where P. falciparum hrp2/3 deletions are frequent. The Noul miLab is a fully automated portable digital microscope that prepares a blood film from a droplet of blood, followed by staining and detection of parasites by an algorithm. Infected red blood cells are displayed on the screen of the instrument. Time-to-result is approximately 20 minutes, with less than two minutes hands-on time. We evaluated the miLab among 659 suspected malaria patients in Gondar, Ethiopia, where P. falciparum and P. vivax are endemic, and the frequency of hrp2/3 deletions is high, and 991 patients in Ghana, where P. falciparum transmission is intense. Across both countries combined, the sensitivity of the miLab for P. falciparum was 94.3% at densities >200 parasites/μL by qPCR, and 83% at densities >20 parasites/μL. The miLab was more sensitive than local microscopy, and comparable to RDT. In Ethiopia, the miLab diagnosed 51/52 (98.1%) of P. falciparum infections with hrp2 deletion at densities >20 parasites/μL. Specificity of the miLab was 94.0%. For P. vivax diagnosis in Ethiopia, the sensitivity of the miLab was 97.0% at densities >200 parasites/μL (RDT: 76.8%, microscopy: 67.0%), 93.9% at densities >20 parasites/μL, and specificity was 97.6%. In Ethiopia, where P. falciparum and P. vivax were frequent, the miLab assigned the wrong species to 15/195 mono-infections at densities >20 parasites/μL by qPCR, and identified only 5/18 mixed-species infections correctly. In conclusion, the miLab was more sensitive than microscopy and thus is a valuable addition to the toolkit for malaria diagnosis, particularly for areas with high frequencies of hrp2/3 deletions.

show abstract

Section: Discussionmentioning

confidence: 99%

A digital microscope for the diagnosis of Plasmodium falciparum and Plasmodium vivax, including P. falciparum with hrp2/hrp3 deletion

Ewnetu,

Badu,

Carlier

et al. 2024

PLOS Glob Public Health

View full text Add to dashboard Cite

show abstract

“…It is a simple method based on the isothermal amplification, not requiring special equipment, and producing results that can be read visually or with a real-time turbidimetry. LAMP allows to reduce the time for the result within the recommended 2 h for the diagnosis of malaria and showed to have high efficiency, allowing DNA amplified 10 9 -10 10 times in 15-60 min [87][88][89]. Advantages of LAMP based assays also include the use of small amounts of blood samples on filter papers and the tolerance of inhibitory substances present in blood samples (hemoglobin/immunoglobulin), but it currently lacks sufficient accuracy [21].…”

Section: Molecular Methodsmentioning

confidence: 99%

The Laboratory Diagnosis of Malaria: A Focus on the Diagnostic Assays in Non-Endemic Areas

Calderaro,

Piccolo,

Chezzi

2024

IJMS

View full text Add to dashboard Cite

Even if malaria is rare in Europe, it is a medical emergency and programs for its control should ensure both an early diagnosis and a prompt treatment within 24–48 h from the onset of the symptoms. The increasing number of imported malaria cases as well as the risk of the reintroduction of autochthonous cases encouraged laboratories in non-endemic countries to adopt diagnostic methods/algorithms. Microscopy remains the gold standard, but with limitations. Rapid diagnostic tests have greatly expanded the ability to diagnose malaria for rapid results due to simplicity and low cost, but they lack sensitivity and specificity. PCR-based assays provide more relevant information but need well-trained technicians. As reported in the World Health Organization Global Technical Strategy for Malaria 2016–2030, the development of point-of-care testing is important for the improvement of diagnosis with beneficial consequences for prompt/accurate treatment and for preventing the spread of the disease. Despite their limitations, diagnostic methods contribute to the decline of malaria mortality. Recently, evidence suggested that artificial intelligence could be utilized for assisting pathologists in malaria diagnosis.

show abstract

“…It is a simple method based on the isothermal amplification, not requiring special equipment, and producing results that can be read visually or with a Real-time turbidimetry. LAMP allows to reduce the time for the result within the recommended 2 hours for the diagnosis of malaria and showed to have high efficiency, allowing DNA amplified 10 9 -10 10 times in 15-60 min [87][88][89]. Advantages of LAMP based assays also include the use of small amounts of blood sample on filters papers and the tolerance to inhibitory substances present in blood samples (hemoglobin/immunoglobulin), but it currently lacks sufficient accuracy [21].…”

Section: Molecular Methodsmentioning

confidence: 99%

The Laboratory Diagnosis of Malaria: A Focus on the Diagnostic Assays in Non‐Endemic Areas

Calderaro,

Piccolo,

Chezzi

2023

Preprint

View full text Add to dashboard Cite

Malaria is rare in Europe, but it is a medical emergency and programs for its control should ensure access to early diagnosis and prompt treatment within 24-48 h of the symptom’s onset. The consistent number of imported malaria cases and the risk of reappearance of autochthonous cases stimulated laboratories in non-endemic countries to evaluate diagnostic methods/algorithms: microscopy remains the gold standard, but with limitations. RDTs have greatly expanded the ability to diagnose malaria for rapid results due to simplicity and low cost, but they lack sensitivity and specificity. PCR-based assays provide more relevant information but need well-trained technicians. According to WHO global Technical Strategy for Malaria 2016-2030, the future direction for a rapid diagnosis is the development of Point-Of-Care Testing, which would be helpful for prompt/accurate treatment and for preventing the diseases spread. Despite the limitations of current diagnostic methods, they play important roles in dealing with the global malaria situation, including decreasing its incidence. Recently evidence suggested that Artificial Intelligence could be utilized for assisting pathologists in malaria diagnosis. Future studies need to be conducted to see whether this system can be used for routine malaria diagnostic procedures.

show abstract

Sensitive Detection of Asymptomatic and Symptomatic Malaria with Seven Novel Parasite-Specific LAMP Assays and Translation for Use at Point-of-Care

Abstract: The spread of Plasmodium falciparum parasites with Pfhrp2 / 3 gene deletions presents a major threat to reliable point-of-care diagnosis with current rapid diagnostic tests (RDTs). Novel molecular diagnostics based on nucleic acid amplification are needed to address this liability.

Cited by 6 publications

References 52 publications

A digital microscope for the diagnosis of Plasmodium falciparum and Plasmodium vivax, including P. falciparum with hrp2/hrp3 deletion

A digital microscope for the diagnosis of Plasmodium falciparum and Plasmodium vivax, including P. falciparum with hrp2/hrp3 deletion

The Laboratory Diagnosis of Malaria: A Focus on the Diagnostic Assays in Non-Endemic Areas

The Laboratory Diagnosis of Malaria: A Focus on the Diagnostic Assays in Non‐Endemic Areas

Contact Info

Product

Resources

About