System monitors presence of novel coronavirus in air

By André Julião | Agência FAPESP – Technology developed by means of a collaboration between the startup Omni-electronica and Hospital das Clínicas (HC), the general and teaching hospital run by the University of São Paulo’s Medical School (FM-USP) in Brazil, enables scientists to capture samples of the novel coronavirus in the air and monitor this health hazard in crowded environments. The researchers believe the system may be useful in the post-pandemic economic recovery.

The startup’s founders met while they were graduate students at the University of São Paulo’s Engineering School (POLI-USP) and used funding from FAPESP’s Innovative Research in Small Business Program (PIPE) to develop Spiri, a multi-sensor system designed to monitor indoor air quality (read more at pesquisaparainovacao.fapesp.br/908).

Now SPIRI can also detect SARS-CoV-2. “We have a very robust indoor air quality database, and we know how respiratory viruses are transmitted and how infections intensify in winter. When the coronavirus pandemic began, we saw quite clearly that indoor transmission was the most likely scenario even though little was said about it even by the World Health Organization [WHO],” said Arthur Aikawa, Omni-electronica’s CEO and principal investigator for the study.

Spiri is a subscription service. An on-site device containing several integrated sensors transmits data to a control center, which generates online reports in real time to enable technicians to advise subscribers on ways to improve air quality.

A group of researchers spent two months at HC analyzing air quality based on samples collected at two-, six- and eight-hour intervals. They coupled Spiri to a collector with a filter made of polytetrafluoroethylene (PTFE) to capture the virus. They sent the filter to a laboratory for real-time PCR testing to detect the virus’s RNA. This is the method used to test human subjects for COVID-19 using a nasopharyngeal swab.

Even in environments with a high incidence of bioaerosols, such as hospital ICUs in which tracheostomies and intubation are performed, collection had to last eight hours to capture the virus. Physicians Alessandro Wasum Mariani, Renato Astorino Filho, and Paulo Henrique Peitl Gregório also took part in the project team.

“The HC hospital and laboratory complex has many fairly old buildings with windows everywhere. Although by definition there are plenty of viruses on the site, they don’t remain in the air for long thanks to adequate ventilation,” said Aikawa, whose partners in the firm are Matheus Manini and John Esquiagola. Both also collaborated on the research project. The startup is based at the Center for Innovation, Entrepreneurship and Technology (CIETEC), an incubator run by the University of São Paulo (USP) and the Nuclear and Energy Research Institute (IPEN).

Risk indicators

A paper on the results of the study is being prepared for publication in a scientific journal. Meanwhile, the firm has developed an even more complete air quality monitoring protocol. Real-time measurement of carbon dioxide, particulates, temperature, and humidity was already possible with Spiri. This initial protocol alone can guarantee adequate airflow to avoid high levels of respiratory viruses in the environment. Now it is also possible to conduct regular tests to detect circulation of the novel coronavirus.

“Testing for SARS-CoV-2 is possible with this protocol, but difficult on a large scale for reasons of time and money. Labs take five days to produce a result,” Aikawa said. “Spiri on its own, however, is a real-time indicator of viral transmission so that staff knows whether the necessary precautions are being taken to prevent it.”

Integration of Spiri with monitoring of strategic locations such as bus terminals and subway stations to detect viral aerosols can contribute to a safer economic reopening, he added. Based on the tests performed at the hospital, the researchers created risk indicators pointing to variations in contamination potential according to what is detected.

For more information about the startup, visit en.omni-electronica.com.br/.