Context: In my world, there is a lyssavirus strain with a long and complicated history that was accidentally developed into an extremely contagious bioaerosol; a doomsday biological weapon. Primates can get infected with it via inhalation, ingestion (drinking tainted water or eating contaminated fish) or blood. Depending on how one got infected, how compromised his immune system is and many other factors, first symptoms will become apparent in at least 85-90 hours, while in the most cases an infected person might not notice anything up to 2 weeks. So there must be ways of detecting any possible leaks and contamination incidents before it's too late.

Anyway... Due to a chain of unfortunate events a limited amount of bioaerosol gets vented out of an underground storage facility. Several minutes later the leak is detected, vents shut off and the facility goes on the highest level of biological alert. This includes sending a special helicopter equipped with some sort of "virus detector" - a machine that literally sucks in the air and detects the presence of the aforementioned bioaerosol - to check the surrounding areas to estimate a probable spread zone.

Question: Is a bioaerosol/virus detector possible? Is it possible to purposefully make bioaerosols into something quickly and easily detectable, the same way the propane gas, naturally odorless, can be detected because of artificially added odorants?

  • 1
    $\begingroup$ Just to make a point, there's nothing stopping you from introducing a color, a smell, an inert-but-trivially-detected gas (e.g., xenon) into (insofar as I know) any aerosol that has biological components in it like a virus. On the other hand, something that can detect the actual biological agent and detect it quickly? That's usually the stuff of Hollywood, but it's not impossible - especially for an agent you already know exists - but it very much depends on what "quickly" means. An at-home COVID test requires 10-30 minutes to demonstrate proof (but that's not a direct test, might not be one). $\endgroup$
    – JBH
    Commented Oct 22, 2022 at 22:31
  • $\begingroup$ In the next 50 years or so, it's expected that there will be little biochips that can detect novel viruses... the trouble is that there are oodles of the things out there floating around that are completely irrelevant to human existence (even a few that are pretty awesome... wouldn't it be great to find one that just hates malaria?). False positives aren't a thing, once a virus starts its ramp up to pandemics, its qty would just spike off the charts. But by then, you have to wonder if it's not too late to do something about it. These technologies will probably work best in sealed ecosystems. $\endgroup$
    – John O
    Commented Oct 25, 2022 at 15:19

4 Answers 4


Yes.* It is possible.

But there is multiple asterisks and caveats. Need to get the false negatives and false positives to be as low as possible.

The outer shell/coating of the virus needs to be mostly consistent, that is it can't be changing to rapidly in subsequent versions else detectors will stop detecting. That is how prone is the virus to having its coat mutated.

The virus is related to existing viruses, how well can the new one be differentiated from the old?

Often in the faster the test the less certain the result.

Many tests are one time use, to make a continuously operating detector need to be able to trigger then clear.

Solution form

Biological systems have means to do this such as being able to smell particular compounds. So a nose type system built to detect multiple aspects combine the output with some machine learning to know what combo of factors is alarm and what strength. This would be very handy to have and eventually we will have systems like this.

We just need to figure out how existing biological systems do it and replicate them but tuned for target of interest.

But we are years away from this. Many difficult problems.


Add in a fluorescent light marker to their DNA

enter image description here

There are jellyfish that glow in the dark. They produce a protein that emits light when you shine light on it. Your virus also has this added, so a giant UV light can detect them, much like this cat is detectable in the dark because of added glow in the dark DNA.

  • 2
    $\begingroup$ It is worth noting that adding fluorescent markers like this is an extremely common technique in microbiology. The basic idea is that counting the number of virions (individual molecules of a virus) in a sample is very hard, but measuring how much the sample fluoresces under UV light is very easy, so if you make the virions fluoresce a spectrometer can tell you the concentration of virons in a sample in seconds. $\endgroup$
    – E Tam
    Commented Oct 22, 2022 at 23:49
  • 1
    $\begingroup$ Only issue is.. what if the virus strain that escaped has not been modified to do this ? You can't enforce the mutation afterward.. when this virus was developed as a weapon, it is not plausible they would build it in beforehand, making the weapon clearly visible. $\endgroup$
    – Goodies
    Commented Oct 23, 2022 at 10:35
  • $\begingroup$ " the same way the propane gas, naturally odorless, can be detected because of artificially added odorants?" op said you could artificially add something to make it easier to detect. $\endgroup$
    – Nepene Nep
    Commented Oct 23, 2022 at 12:22
  • 1
    $\begingroup$ @ETam agreed, slapping a GFP into anything you’re genetically modifying for a matter of convenience is so common that I’d almost be surprised if they hadn’t done it (assuming it doesn’t interfere with capsid packing due to bulk, but lyssavirus are big). The rabies virus (which is the only lyssavirus that commonly infects primates, iirc) in particular is often modified in the lab to carry fluorescent taggers and “light up” the neurons they infect, in order to visualise neural tracts. There are loads of fluorescent rhabdovirus constructs in labs already. $\endgroup$
    – Ottie
    Commented Oct 25, 2022 at 7:08
  • $\begingroup$ Viruses can't do this, as far as I'm aware. They're not biological organisms... the DNA itself doesn't glow, it just codes for proteins that do. Large, humongous proteins... the sort of thing you probably can't expect the hijacked (soon-to-be-dead) cell to manufacture... and if it did, the virus wouldn't have any place to put it (these things tend to get in the way of cell receptor or so I thought). $\endgroup$
    – John O
    Commented Oct 25, 2022 at 15:18

They'll know how to detect it

One advantage your scientists have is they know what virus they are looking for.. and they know that virus very well. They synthesized the little bugger ! This also means that they already have detection devices for use in the laboratory. Else they wouldn't be able to e.g. assert the amount of virus, in experiments. In short, don't worry, some detector will already be present.

..but how to do it outside the laboratory

Only issue is: the medium. It may not be possible to use the existing detector, because it was always used in laboratory circumstances and not in the open air.

However, components used for the laboratory detector they already have, could be used for the detector you want to develop.


Enzyme-Linked Immunosorbent Assay:

While not instant, lab tests certainly do exist that should get a result back in maybe 20 minutes or less. Since you are only looking for ONE thing, you have produced antibodies to it in a sample organism (frequently sheep, but most animals will work). The antibody is linked to an enzyme that produces an intense test reaction (usually a color change or fluorescence). A sample is obtained, solubilized, and mixed with the enzyme-antibody conugate. This is then run through a test system (usually run across the antibody bound to a filter paper). The "sandwich" of enzyme-antibody-antigen-bound antibody binds to the paper, then forms a color as the enzyme reacts with a substrate.

While this sounds complex, many OTC pregnancy tests operate by a variation of this antibody-binding test method. So a rapid test for your virus is entirely possible in fairly short order.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .