The work in the project has been on developing the three COVID-19-tests PATHPOD, PATHLOCK and PATHAG, as well as performing the field testing of samples collected in China. Also, method development and studies of the viral diversity of human clinical samples have been carried out to give a better understanding of the variability of corona viruses. Studies on 21st century epidemics have been completed to provide a better basis for understanding the COVID-19 pandemic and its impact on the human population.
PATHAG, an antigen agglutination test, and PATHLOCK, a simple lateral flow test, were unfortunately unsuccessful and the work on these was discontinued early on in the project. The PATHPOD device, which was based on LAMP amplification of virus RNA, was successful and was developed in two versions, one based on turbidity measurements and one based on fluorescence detection.
For the PATHPOD we needed to first develop primer sets suitable for detection of SARS-CoV-2 virus causing COVID 19. These were developed based on publication and genome sequences from the web (www.gisdaidm.org) and tested for specificity and sensitivity for detecting COVID 19. When using purified RNA, the sensitivity was 94% and specificity 96.7% compared to the Altona PCR reference method.
The first design of the PATHPOD resulted in 10 PATHPOD instruments and 1000 cartridges (for 10000 tests). These instruments and cartridges were used to determine the analytic specificity (100%), analytic sensitivity (~30-50 copies) as well as clinical evaluation. This first version of the instrument had a lower sensitivity than we expected. To improve the sensitivity and LOD of the PATHPOD, a version 2 of the instrument was developed based on fluorescence detection. The PATHPOD v2 has shown 99% relative accuracy, 97,5% relative specificity, and 100% relative sensitivity to RT-qPCR, with the LOD improved to being 2.5-5X higher than RT-PCR. Due to time constraints and several delays caused by the pandemic, we were only able to test PATHPOD v1 with human, animal and environmental samples in China. The results showed that the PATHPOD performance greatly depends on the sample type and clearly works better for human samples, for which it has been validated in the laboratory.
Viral diversity and evolution are important in order to follow the development of the pandemic as well as the efficiency of tests and vaccines. Therefore, MUW established a method that does not discriminate against mutated virus sequences and is able to reliably detect also low abundant sequence variants.
We analysed and compared the epidemiological dynamics of selected epidemics of the 21st century using historical surveillance data to identify differences and similarities both in diseases' natural history and public health response measures.
Data analyses were performed on mortality data (COVID-19 mortality and excess mortality for all causes) and data on estimated prevalence of the infection, at the national and European level. A systematic listing of containment models and measures and their impact in different European settings was completed in this last period.
The work has been described in several peer-reviewed publications and has resulted in 1 patent. Moreover, the consortium has produced a flyer, set up and managed the CORONADX online communication channels (website and social media), produced and distributed public communication contents aimed at raising awareness and visibility around CORONADX (such as press and news release and video teasers), created a series of Fact or Myth? posts aimed at clarifying common misunderstandings and providing useful, science-based recommendations related to the topic towards the general public.
