A critical bottleneck for equitable access to population-scale molecular diagnostics is the limited availability of rapid, inexpensive point-of-care tests especially in low- and middle-income countries. Here, we developed an open-source Reverse transcription loop-mediated isothermal amplification (RT-LAMP) molecular assay for the detection of respiratory RNA virus infections. It is based on non-proprietary enzymes, namely HIV-1 reverse transcriptase, Bst LF DNA polymerase and UDG BMTU thermolabile uracil DNA glycosylase. Formulated as liquid or lyophilized reaction mixtures, these reagents enable sensitive colorimetric detection of respiratory samples without the need for prior nucleic acid isolation. We evaluated our open-source lyophilized RT-LAMP assay on clinical samples with suspected COVID-19 infection, demonstrating high sensitivity and 100% specificity compared to the gold standard Reverse transcription quantitative polymerase chain reaction (RT-qPCR). Reaction performance was unaffected by prolonged storage of lyophilized reagents at ambient or elevated temperatures. As a proof of concept, we evaluated the robustness and ease-of-use of lyophilized RT-LAMP reaction mixes through independent laboratory testing of COVID-19 samples in Ghana. Overall, our open-source RT-LAMP assay provides a flexible and scalable point-of-care test that can be adapted for rapid detection of various pathogens in resource-limited settings.

The authors have declared no competing interest.

M.M. and M.J.K. were supported by the Vienna Science and Technology Fund (WWTF) through project COV20-031. This project received funding from the VW foundation (grant 9A027) given to TReND in Africa, as well as funding from the Mila Charitable Organisation. The IMP receives generous institutional funding from Boehringer Ingelheim and the Austrian Research Promotion Agency (Headquarter grant FFG-852936), and IMBA is generously supported by the Austrian Academy of Sciences. Research in the lab of A.P. was supported by the Austrian Science Fund (START Projekt Y 1031-B28, SFB RNA-Deco F 80). Research in the lab of J.B. was supported by the European Research Council (ERC2015-CoG - 682181). F.A and G.A.A. were supported by a Science for Africa Foundation (SFA)/Wellcome Developing Excellence in Leadership Training and Science (DELTAS) in Africa grant (DEL-22-014: Awandare, G). Work in the L.M.-A. laboratory was supported by grant PID2019104176RB-I00/AEI/10.13039/501100011033 of the Spanish Ministry of Science and Innovation, and an institutional grant of the Fundacion Ramon Areces. The laboratory of J.M.P. at IMBA received funding from the Austrian Academy of Sciences, the Medical University of Vienna, the Swedish Research Council (2018-05766), the T. von Zastrow foundation, and the Innovative Medicines Initiative 2 Joint Undertaking under grant agreement No 101005026. This Joint Undertaking receives support from the European Unions Horizon 2020 research and innovation programme and EFPIA.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethics Committee of the City of Vienna gave ethical approval for the work in Vienna, Austria (#EK 20-292-1120). Oro/Naso-pharyngeal samples in Vienna (oro/nasopharyngeal swabs and gargle) were obtained as part of a clinical performance study approved by the local Ethics Committee of the City of Vienna (#EK 20-292-1120). Informed consent was obtained from all patients. The Ghana Health Service Ethics Review Committee gave ethical approval for the work in Accra, Ghana (GHS-ERC 011/03/20). Sputum samples in Ghana were obtained as part of a larger COVID-19 surveillance study from individuals who tested for COVID-19 at the West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, during the pandemic. A written informed consent was obtained from each participant before enrollment.

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Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

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The original contributions presented in the study are included in the article/Supplementary Material. Further inquiries can be directed to the corresponding authors.

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