Can we track COVID-19 with wastewater?

Water and Bubbles

Certainly, yes! COVID-19 is not the first viral disease to hit the world. Before COVID-19, there was hepatitis A, norovirus, poliomyelitis, aseptic meningitis, hand, foot, and mouth disease, pleurodynia, myocarditis, and respiratory tract infections. The viruses causing these diseases have been successfully identified by testing wastewater. The same principles can be applied to the new coronavirus.

Why it is important to track coronavirus with wastewater

If you have been tested for COVID-19, you certainly understand how cumbersome the testing can be. In the first place, being a fairly new disease, the testing kits are still in fairly low supplies, especially in African countries. Even developed countries are really rationing the use of the test kits, so as not to completely go out of stock. New orders take up to 3 months to arrive at the designated hospitals. 

Coming to the hospitals and other facilities reserved for testing, queues are usually long enough to dissuade the most willing soul. In short, it takes quite a lot of time for the actual test to be done. And even after the testing is done, the collected samples have to be sent to experienced lab technicians for analysis using the PCR machine. Then follows the tallying of test results and reporting to the people who were tested. The whole process can end up taking up to one full week. This is quite dangerous, bearing in mind how the virus spreads like wildfire. 

Also, due to strained supplies, the tests are not administered to every Tom, Dick, and Harry. The Centers for Disease Control and Prevention advise that you should get tested if:

  • You have the coronavirus symptoms
  • You have been in close contact for more than 15 minutes with a COVID-19 patient
  • Your doctor recommends the test

Remember, it takes an average of about 5-6 days for someone infected to start showing symptoms like fever, dry cough, tiredness, aches, sore throat, diarrhea, conjunctivitis, headache, loss of taste and smell, shortness of breath, loss of speech, and skin rashes. In some cases, it takes up to 14 days before the symptoms start showing. This implies that, before someone soberly makes the decision to get tested, the virus has already been in his or her body for 1-2 weeks. 

In addition to that, a good number of people are asymptomatic to the virus – i.e. they have the virus but won’t show any symptoms. They may never get tested in good time, yet they all along spread the virus to others.

As such, health authorities don’t get to know the actual number of infections in good time. That is why hospitals overflow with patients all at once. And when the hospitals get overwhelmed, hundreds of patients are sent back home while others end up dying due to the effects of crowded conditions.

If the authorities had a system of detecting the spread of the virus early enough, such a last-minute rush to save lives could be avoided. For instance, about 3 months into the initial outbreak of 2020, Paris officials reported that there were only 10 positive cases in the region. But lo and behold, the cases skyrocketed within a few days, sending the health services into a great panic.  

It is possible to track COVID-19 with wastewater

One way to detect the presence of the virus in a community is to test wastewater. Liquid and solid samples are collected from waste treatment plants for testing. Expert studies reveal that the virus can be identified in human feces about 3-4 days before the victim starts showing the symptoms. This is true in more than half of those infected. 

Do not underestimate the importance of those 72 hours. From what health experts experienced in 2020, even 24 hours of adequate preparations can significantly save human lives. 

One advantage of tracking COVID-19 with wastewater is that every healthy person visits the toilet on regular basis. Though unknowingly, this translates to regular deposition of biological samples. And this will go a long way in informing health authorities about the presence and spread of COVID-19 in a given community. 

When carrying out the SARS-CoV-2 tests on wastewater, both solid and liquid samples should be analyzed. It is reported that the coronavirus has a higher affinity for solids.

If such tests are carried out on a regular basis, additional information like the trend of the disease can be retrieved. Health officials will be able to tell whether the infections are increasing or the curve is flattening. Likewise, they will be able to identify hotspots and impose the necessary mitigation measures.