Opteev is a technology company that makes the world a safer place for humanity by bringing new products to market to improve air quality in the environments we live in, from workspaces to schools and everywhere in between. Our innovative products screen people and places to deliver a sense of comfort and security for everybody to enjoy their lives without reservation.


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// FAQ

ViraWarn Frequently Asked Questions

What is ViraWarn?
ViraWarn by Opteev is the first ever plug-in sensor for indoor airborne virus detection that provides instantaneous results to help improve indoor air quality and support safe indoor gathering. It has the a biosensor that can detect Sars-Cov2 and other spike-protein/enveloped viruses in the air. The device uses Edge computation and is IoT enabled to process and display data from all the relevant sensors and give both audio and visual warnings.
Why it is important to know what the viral load is in the air?
Viral load is the number of viral particles present inside a sample. The higher the viral load in an individual, the higher the chance is that that person can transmit the virus. It’s one of the key factors that determines the probability of a person getting infected. Research shows that 44 percent of transmissions can occur before the first signs of infection. (He, X e al., 2020). ViraWarn alerts you in this scenario, so you can then take measures to prevent infection and transmission. This real-time detection of aerosolized viral presence in your room can help protect you from getting COVID-19 and its variants.
He, X., Lau, E.H.Y., Wu, P. et al. Temporal dynamics in viral shedding and transmissibility of COVID-19. Nat Med 26, 672–675 (2020). https://doi.org/10.1038/s41591-020-0869-5
How does it sense viral load in air?

Each viral family has a unique surface property which determines its infectivity. Aerosolized viruses have extensive glycoprotein structures present on its surface that are different for different viruses. Thus, each type of virus has a unique surface charge distribution on the viral coat. This unique charge distribution, coupled with the resultant colloidal solution gives a unique platform for precise detection of aerosolized viruses. The bio sampler mechanism in the machine draws air inside and measures the electrical signal generated. Presence of a virus generates electrical signals that the algorithm program reads to generate a warning alarm and red light.

What level of viral load in the air can be enough to infect a person with or without a mask?
The estimated viral load in a room with an infected individual who was coughingfrequently would be very high, with a maximum of 7.44 million copies/m3 from anindividual who was a high emitter. However, regular breathing from an individual whowas a high emitter was modeled to release up to 1248 copies/m3 (Riediker M et. Al.,2020). The host wearing N95 or reusable elastomeric respirator may not receive in more than 5 percent, which may, however, constitute more than a few hundreds of payloads of thevirus. The probability of getting infected under such a scenario is still possible, althoughit is very minute (van der Sande, M. et al.,2008). The FFP2 masks were observed toprovide adults with about 50 times as much protection as homemade masks, and 25times compared to surgical masks (van der Sande et al., 2008). Similarly, another studyhas elaborated that a surgical mask (that filtered 89% of viral particles) was about three times better in controlling the viral transmission than that of a homemade mask. (Davieset al., 2013)
Riediker M, Tsai D. Estimation of Viral Aerosol Emissions From Simulated Individuals With Asymptomatic to Moderate Coronavirus Disease 2019. JAMA Netw Open.2020;3(7):e2013807. doi:10.1001/jamanetworkopen.2020.13807
Davies, A., Thompson, K.A., Giri, K., Kafatos, G., Walker, J., Bennett, A., 2013. Testing theefficacy of homemade masks: would they protect in an influenza pandemic? DisasterMed. Public Health Prep. 7, 413–418. https://doi.org/10.1017/dmp.2013.43.
If an infected person enters the room, how long will it take for the sensor to detect that the air is contaminated with a virus?
The moment the infected individual sheds aerosolized virus into the air, ViraWarn will be able to detect it within one to five minutes and immediately notify you. However, it depends on several factors like the viral load discharged by the infected person--by coughing and sneezing or the degree of infection--and various other factors like size of
the room, its ventilation, humidity, temperature and particulate matter present in the room.
How should ViraWarn be used to keep people safe?

The ViraWarn alert is like a fire alarm in that it signals when something needs to be responded to, but it’s best used as part of a comprehensive BioViral Prevention Plan. Follow the link to learn how to create an effective BioViral Prevention Plan.

How does ViraWarn sense the virus?
ViraWarn, is a bio-sampler that detects aerosolized viruses in real time, which have extensive glycoprotein structures present on their surface. This glycoprotein moiety is different for various viruses. Each type of virus has a unique surface charge distribution on the viral coat. This unique charge distribution, coupled with the resultant colloidal solution gives a unique platform for precise detection of specific aerosolized viruses.
Can ViraWarn sense influenza?
Yes. Aerosolized viruses have unique surface charge distribution due to the specific structural motifs of the glycoprotein coupled with their defined arrangement. ViraWarn exploits this property that allows it to specifically identify influenza and other aerosolized viruses. Our research shows the efficacy of influenza detection, and we’ve found positive detection for various amount of viral load.
After the alarm goes off, can ViraWarn detect who is spreading the Virus?
No. ViraWarn only detects the virus in the air and alarms the people present there. It cannot detect the source of the virus especially when multiple individuals are present in its immediate environment.
What is the false positive and false negative rate for ViraWarn? Has there been any beta study?

The false positive rate is 0.375, and the false negative rate is 0.1875, which means that 71.8 percent of the time, ViraWarn is detecting correctly. Justification of this false positive data can be given by literature reports suggesting that the well-established RT-PCR detection study has a false positive rate of 0-16.7 percent*. Our device has a similar false positive rate (Andrew N. Cohen et al., 2020). There are many on-going beta tests, and a few of those have been concluded. Our recently concluded tests, which have been done in collaboration with various national institutes, show high effectiveness of ViraWarn machine with various aerosolized viruses. The device has successfully detected various types of aerosolized viruses such as SARS-COV2, influenza, and more.

Andrew N. Cohen and Bruce Kessel. False positives in reverse transcription PCR testing for SARS-CoV-2. medRxiv 2020.04.26.20080911; doi: https://doi.org/10.1101/2020.04.26.20080911

Has ViraWarn been tested with Covid-19 patients?
Yes. It has been extensively tested with Covid and non-Covid patients, both in home isolation as well as in the hospital. The results clearly show that ViraWarn is effectively able to detect the COVID-19 virus. This detection was observed even for asymptomatic patients. Despite the lower viral load in asymptomatic patients, the device had a high success rate of SARS-CoV2 detection. This also showcases its variable load detection
What are the other important air quality parameters for virus transmission that ViraWarn detects?
The device is equipped with various sensors to monitor temperature, humidity, level of particulate matter and carbon dioxide present in the environment. In addition to viral load detection, it’s able to detect pollutants in the air. This feature was included in the device as there has been extensive research that demonstrates a direct correlation between pollution and viral transmission
If a ViraWarn alert is triggered, and room occupants are wearing masks and social distancing, will they be infected by COVID-19?

This depends upon several other factors like the viral load discharge, particle matter (PM) status, viral aerosol stability, temperature, humidity and ventilation in that place, which might influence the chance of virus transmission. ViraWarn also suggests social distancing based on the above-mentioned parameters to avoid such a scenario.

If hosts are wearing an N95 or reusable elastomeric respirator, then they may not receive more than 5 percent, which may, however, constitute more than a few hundreds of payloads of the virus. The probability of getting infected under such a scenario is still possible, although it’s very minute.

Van der Sande, M., Teunis, P., Sabel, R., 2008. Professional and home-made face masks reduce exposure to respiratory infections among the general population. PloS One 3, e2618. https://doi.org/10.1371/journal.pone.0002618.
How often does the cartridge need to be changed and how do you change it?
You’ll get an alert on your mobile phone through the ViraWarn mobile app, and a red LED light will appear on the device. This is how you know it’s time to change the cartridge.
After getting the notification, rotate the detector in counterclockwise direction to detach it from the ViraWarn sensor. Before installing the new cartridge, rotate it
counterclockwise to break the seal. Then, place the new detector below the sensor and rotate it in a clockwise direction to attach it with the ViraWarn sensor.
How often you change the cartridge depends on individual usage but can run up to 200 hours.
How does ViraWarn separate the effect of particle matter from that of thevirus signal?
Virus particles, particle matter level and temperature affect ViraWarn’s signal. Through research, we isolated the effect of temperature and particle matter on the ViraWarn signal. ViraWarn uses advanced estimation algorithms to cancel out the effects of particle matter and temperature while continuously monitoring both in the environment using its built-in sensors. It’s state-of-the-art Machine Learning (ML) algorithm detects virus particles accurately.
What’s the recommended temperature range for ViraWarn?
The device works within a temperature range of 10
°C to 40°C, which is 50°F to 104°F
Where should ViraWarn be placed in a room so that the alarm works properly?

The response time and effectiveness of the device depends on the proper placement of ViraWarn in a room and the size of the room. As a rule of thumb, one ViraWarn device should be used per every 100 square feet. The device comes with instructions on where ViraWarn should be placed.

Does the number of infected people in a room affect the response of the device?
Yes, the more infected people in a room, the more viral load will be in the air. Virus detection will be faster and more accurate in this case.
Does ViraWarn need internet connectivity?
No, the device can work with or without internet connectivity. Internet connectivity allows users to see data anywhere in the world and receive SMS/email alerts in case of a viral breakout.
What’s the difference between the ViraWarn models?

There are two different ViraWarn models: X and XL. The light-weight, compact ViraWarn X plugs directly into an electrical outlet, mounting to the wall.  ViraWarn XL is a standalone device with a larger media chamber, meaning users can go longer in between changing cartridges, which is important for uses like schools, offices and medical facilities where people are focused on their task at hand.

// Make ViraWarn Part of Your BioViral Prevention Plan

A new layer of defense, ViraWarn helps prevent the spread of viruses in your indoor spaces!

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