PCR Test: How Close Does the Swab Really Get to the Brain?

Every disease requires a solid diagnosis, and COVID-19 is no exception. But the primary tool for detecting the virus has become controversial. The so-called PCR test has faced significant resistance because it requires inserting a special swab through the nose to reach the nasopharynx. What is the public afraid of? That the swab could cause brain damage. So... how close does the PCR swab really get to the brain? The Institute of Human Anatomy YouTube channel gives us the answer.

PCR Test: How It Works

PCR stands for 'polymerase chain reaction'. In relaxed terms, it is an amplification technique: from a small but well-defined segment of DNA, the material is replicated hundreds of thousands of times, creating an adequate amount for analysis. In the specific case of COVID-19, we often read the expression RT-PCR, or reverse transcriptase PCR. The difference is that its first step requires the reverse transcription of RNA (the SARS-CoV-2 genome is composed of RNA) into DNA.

This is where the nasopharyngeal swab comes in. Several videos available on the Web show that the entire insertion and removal process averages five or six seconds, but the public feels distrust, even fear. 'What if it touches my brain with that?' is just one variant among many questions in the same direction. Fortunately, the Institute of Human Anatomy channel has decided to explore the PCR test in detail.

The 'Insertion Phase' of the PCR Test

The video begins with a sagittal cut that divides the human body into two halves. Immediately we can see the exact location of the brain, and everything that makes up the pharynx, followed by the nasal cavity, the septum that separates both nostrils, and one of the turbinates that moisten and warm the air. Exactly behind the nasal cavity lies the nasopharynx, and that is where the swab must reach.

What about the brain? The answer is nothing. Although the swab travels some distance and causes discomfort, the tip of the swab stays far from the brain, and we must add all the bone structure that protects it. In fact, when specialists operate on the pituitary gland, they do it through the sphenoid sinuses by drilling bone. The protection of that entire area is remarkable.

In Summary...

The PCR test does not damage the brain. Now, that doesn't mean the procedure is free of complaints: many adults end up with tears in their eyes and a couple of insults stuck in their throat, while some children show superior tolerance. There are other alternatives to the PCR test, however, our first line of defense remains prevention. We are all very tired, but we haven't won yet.