With 95 million people infected and close to 2 million deaths globally, the covid-19 pandemic is wreaking havoc. Despite its high similarity with other viruses, the doubts surrounding the SARS-CoV-2 coronavirus have been constant, including those about its existence, origin and transmission.
Laboratories around the world are making an unprecedented effort to answer the questions we face when a new virus appears. The problem is that, contrary to what happens with false information, science is a slow and methodical process that does not always advance at the speed that we would like. Fortunately, time and research end up clarifying these doubts through objective data and scientific consensus.
These are the most common doubts (and hoaxes) surrounding the coronavirus.
The virus has not been isolated or purified
Fake. One of the main arguments of people who deny the existence of the virus is to affirm that it has not been isolated from patients. In general they argue that the viral particle, or virion, cannot be separated from other parts of the cell by its characteristics (density, shape or size) and are indistinguishable from them.
It is true that the size of a viral particle resembles some spherical particles in the cell called vesicles. However, the main difference is that virions are infective and multiply if they come into contact with cells, and vesicles do not. To go deeper here we can find a publication that explains how to distinguish coronavirus virions in cells written by scientists specialized in electron microscopy.
In addition, there is other overwhelming evidence that this new coronavirus has been isolated. These include:
The virus has been isolated and purified from samples from tens of thousands of covid-19 patients around the world and has been published in prestigious scientific journals. Without going any further, the article that released this virus to the world in January 2020 details how virus was isolated from patients with pneumonia in Wuhan to study it in cell cultures. In fact, real photographs of SARS-CoV-2 were shown to the world for the first time here:
The isolated virus can be grown in the laboratory, see each of its proteins, quantify and sequence its genome, used to infect cell cultures and animal models where the disease reproduces. This is an impossible thing to do with vesicles.
We have infective clones of the virus. An infective clone is a copy of the virus genome that we use in the laboratory as a tool that allows us to generate the SARS-CoV-2 genetic variants that we want to study.
In laboratories we can order or buy any of the variants that have been isolated. When requested, they send us a small volume of virus that we can amplify to generate more quantity and be able to do the experiments.
Ultimately, none of this would be possible if the virus had not been isolated.
The SARS-CoV-2 genome is a computer artifact
Fake. To clarify this issue, we will briefly explain how genetic sequencing of patient samples is carried out:
The first step is the genetic sequencing of small fragments (called “reads”) from a patient’s samples. Due to technical limitations, the 30,000 letters of coronavirus genomes cannot be sequenced in one step. Between each of these small fragments there is some overlap. For example, let’s imagine that the short sequences are:
- My sister is called Alejandra and she has
- Alejandra and is 26 years old. He likes to read
- years. Likes to read fantasy books
- Science fiction. His favorite is The Lord of the Rings.
Finally, with this information we need a computer program to be able to identify this overlap and generate the full text: My sister is named Alejandra and she is 26 years old. He likes to read fantasy books. His favorite is The Lord of the Rings.
SARS-CoV-2 does not cause covid-19 because it does not meet Koch’s postulates
Fake. Koch’s postulates (Henle-Koch) are a series of microbiological principles established by Robert Koch in 1884 to correlate the existence of a microorganism and a pathology. He established them based on a bacterium, Mycobacterium tuberculosis , which causes tuberculosis. He later modified them in 1890.
The first and most important thing is that the postulates have been in disuse for decades. The most important reason? Many pathogens do not comply, since there are asymptomatic carriers, subclinical diseases (hepatitis) and extremely variable latency periods (up to 10 years in the case of HIV). Furthermore, no virus sensu stricto will ever fulfill the postulates as enunciated in the 19th century because they need cells or bacteria to multiply, they cannot do so in a pure culture.
Despite everything, the existence of SARS-CoV-2 is being questioned, saying that the World Health Organization itself and the Centers for Disease Control have expressed that the virus does not meet these postulates. One of the arguments used comes from the article where the virus was identified in patients with atypical pneumonia in Wuhan.
Certainly, it says: “Although our study does not comply with all of Koch’s postulates, our analyzes show the involvement of the virus in the Wuhan outbreak.” The reason they said this is because at that time they had not had time to infect experimental animals with the isolated virus to see if they developed the disease. However, today, there are many articles in which the virus has been inoculated in animal models and these have developed the disease.
In summary, Koch’s postulates are principles that, in the 19th and 20th centuries, served to identify pathogens recognizable by the scientific paradigm of the time. Today they are of great pedagogical value, but they are outmatched by the current techniques of molecular biology, biochemistry and genetics.
The virus was created in a laboratory
The appearance of SARS-CoV-2 in Wuhan, a city that consists of two laboratories where people work with coronavirus, has generated controversy about the natural origin of the virus. There are many hoaxes that circulate pointing out the culprits of this pandemic. One of them says that the virus is a fabrication by the Chinese government to use it as a biological weapon and destabilize the rest of the world’s economies.
However, so far the scientific community agrees that the most likely origin of the virus is a zoonosis (a virus that is naturally transmitted from animals to humans and vice versa). In fact, it is known that coronaviruses that infect humans often come from ancestors found in bats.
On the other hand, the most common is that these viral diseases are passed from bats to humans through an intermediate host. SARS-CoV-1 in 2002 and MERS-CoV in 2012 made the leap to humans from civets and dromedaries, respectively. In short, coronaviruses are quite easy to break through the species barrier and jump from one species to another. In fact, SARS-CoV-2 itself has passed from humans to minks, cats, lions, and tigers.
Furthermore, further confirming the hypothesis of the natural origin of the virus, retrospective studies have found bat coronaviruses similar to SARS-CoV-2 in up to 96% of its genome.
The best known artificial origin theory was published by ophthalmologist Li Meng Yan. It is important to note that this is not a real scientific publication nor has it been reviewed by experts on the subject. Rather, it looks more like an opinion piece on a personal blog than a scientific publication.
In this article, the ophthalmologist Li Meng Yan indicates that SARS-CoV-2 was designed using as a base the bat coronavirus ZC45, to which the SARS-CoV-1 protein S was introduced, modified by a sequence of the pangolin coronavirus (Pangolin-CoV). According to this, a representation of the genomes of these viruses from the first to the last letter would be:
However, this theory has numerous loopholes. In reality, the SARS-CoV-2 genome does not show such drastic color cuts as this theory suggests. Rather, the SARS-CoV-2 genome is a mosaic of mutations across its sequence. It would take 1,200 mutations in the most similar bat coronavirus (RaTG13) or 6,000 mutations in the most similar human coronavirus (SARS-CoV-1) to obtain SARS-CoV-2:
The virus has appeared because someone ate a bat soup
Fake. A famous image of a bat soup circulates on the internet that is accompanied by a text indicating that the coronavirus originated in Wuhan because people there eat bats.
However, so far nothing seems to indicate that the virus could jump from a cooked bat to humans. Today, scientists believe that there is an intermediate species that has made it possible for the virus to jump from bats to humans, as happened with civets in the origin of SARS-CoV-1 or with camels in the case of MERS-CoV. .
It is a virus modified from the AIDS virus
Fake. It has been speculated that the SARS-CoV-2 genome contains fragments of HIV. This statement, made by Professor Luc Montagnier, was based on a non-peer-reviewed preprint , which has already been retracted, which indicated that the coronavirus protein S contains four fragments of the HIV glycoprotein, specifically areas with a lot of variability.
Luc Montagnier himself, after analyzing many sequences, the most he came to conclude that, of the 30,000 letters of the SARS-CoV-2 genome, less than 2% show a genetic similarity to different retroviruses. Subsequently, to determine if the appearance of these fragments is significant and not pure coincidence in a genome of 30,000 letters, multiple analyzes of the sequences of the different variables of HIV and SARS-CoV-2 were carried out.
In these studies it was shown that, although there were homologous areas with some HIV nucleotides, these were well below the threshold to be considered significant. In short, it would be like affirming that the book “Don Quixote” is a modified book from Homer’s “The Odyssey” simply because the word “horse” appears in both.
On the other hand, in this study the origin and possible genetic traces of the coronavirus were studied. Of all the sequences analyzed, it was observed that there were 100 sequences with a high homology corresponding to nucleotides of mammals, insects and even microorganisms. This is due to the fact that small hypervariable regions can present homology with tens of thousands of genomes of different classes.
In addition, viruses with a high mutation rate, and specifically coronaviruses, which have a high zoonotic potential, include variants in their genome, homologous to those of the hosts that can harbor them.
There are no experts on coronavirus because it appeared a year ago
Fake. Although the coronavirus (SARS-CoV-2) that causes covid-19 is the most famous, it is not the first we know of. So far there are seven described coronaviruses that infect humans and the first documents that identify these human viruses date back to the 1960s.
In fact, four of them are responsible for some of the common colds (HCoV-229E, HCoV-OC43, HCoV-NL63, and HCoV-HKU1) and have a very low mortality rate. The other three human coronaviruses are those previously mentioned: SARS-CoV-1, MERS-CoV and the current SARS-CoV-2.
In summary, coronaviruses are viruses that infect both humans and wild and domestic animals and that have been circulating for decades. For this reason, researchers have been studying them since the 1960s, both in veterinary medicine, medicine, microbiology and preventive medicine. There are research groups dedicated exclusively to them and several doctoral theses of the authors of this article were studies of between five and eight years on human and animal coronaviruses, their pathogenesis and the development of vaccine candidates.
PCR tests as a target for creating hoaxes
During the pandemic, numerous hoaxes have circulated about the polymerase chain reaction (PCR) for the detection of SARS-CoV-2. It has been said that, according to statements by Kary Mullis, its creator, PCR would not be useful to detect the new coronavirus. It is also said that they are not specific because they detect other coronaviruses and human chromosome 8.
The diagnosis of SARS-CoV-2 is carried out using a newer variant of traditional PCR, quantitative PCR, or qPCR, which in this case is used for the detection and quantification of SARS-CoV-2. Let’s imagine that the 30,000 letters of the SARS-CoV-2 genome put in that particular order constitute a novel. Each gene would be a chapter, constituted in turn by paragraphs.
QPCR uses three main components (two primers and one probe) that bind, detect and amplify a specific sequence of the SARS-CoV-2 genes. For the diagnosis to be positive, it is essential that the three components together recognize and bind to the sequence of the virus gene. Some of the genes commonly used to detect SARS-CoV-2 are replicase (RdRp), nucleocapsid (N), and spike (S).
It is false that the inventor of PCR said that his method is useless for detecting coronavirus. Reasons for this are that Kary Mullis died in 2019 and that Kary Mullis’s statements stating that “you can find almost anything in anyone” by “being able to amplify a single molecule to something that can be measured” refer to traditional PCR and not to qPCR. This, unlike its predecessor, is capable of quantifying the amount of virus in a sample, making it useful for the diagnosis of infectious agents such as SARS-CoV-2.
It is false that infection by another coronavirus is positive in the PCR diagnosis of SARS-CoV-2. In the same way that two novels with different stories do not have identical chapters or paragraphs, different coronaviruses also do not have identical genes in sequence. The main components of qPCR are designed to specifically detect SARS-CoV-2 genes. In addition, it has been proven that they are not capable of detecting other viruses such as influenza.
It is false that the presence of human chromosome 8 gives false positives. In this hoax it is stated that one of the primers – one of the main components of qPCR – shares a sequence with human chromosome 8. Although the latter is true, for the qPCR diagnosis to be positive, it would be essential that the three main components of qPCR share sequence with human chromosome 8 and not just one of them.
It is false that the qPCR of positive for coronavirus in fruits or goats. This is a fairly widespread hoax due to certain statements by the President of Tanzania, John Magufuli, where he rejects coronavirus test kits imported into his country for being defective. According to him, samples of goats and papayas tested positive. It is true that certain animals have been described as having tested positive for covid-19, but this occurs because certain animals such as minks or cats can become infected with the coronavirus and therefore the tests detect a real infection. So far we do not know what kind of tests were carried out in Tanzania, but qPCR is so specific that it is most likely that it was a contamination when handling the samples. In other words, false positives.
It is false that the new variant from the United Kingdom and Northern Ireland increases the number of false negatives. Although it is true that the qPCR tests that detect protein S are causing problems with the new variant, it must be taken into account that the diagnosis of SARS-CoV-2 is made by detecting more than one gene. Therefore, although the S gene is not detected with the new variant, other genes such as replicase and nucleocapsid are being detected.
In summary, qPCR diagnosis is highly specific and sensitive. It is capable of detecting very small amounts of virus in a patient. In fact, the extent to which qPCR positives implies that the person has an active infection is being debated. This is because, for example, after overcoming the disease it is possible that genetic fragments of the virus are detectable by this technique.
Masks cause hypoxia
Fake. The use of masks is one of the several preventive measures to reduce the probability of contagion of covid-19 in the population. The compulsory use taken by some of the governments has given rise to some part of the population expressing that its use can cause hypoxia.
We know that its use can be uncomfortable, especially for health personnel who have to use it for long periods of time. It can favor the appearance of itching, increased sweating, the presence of acne on sensitive skin and the fogging of the glasses.
Several studies have evaluated oxygen saturation to evaluate cases of hypoxia due to its use. For example, in a study carried out in 2008, the oxygen saturation of surgeons, who wear masks for a long period of time, was evaluated. The results showed a decrease in oxygen saturation in the first hour. However, the study concludes that there is no scientific evidence to know if this decrease was due to the use of the mask or to other factors such as the stress of the surgical intervention.
In summary, to date there is no conclusive data that shows that the use of masks causes hypoxia. The conclusion of many experts, including the world health organization (WHO) and the center for infectious disease control (CDC), is that the use of the mask can save millions of lives by avoiding a decrease in the number of infections .
Masks do not filter the virus
Fake. Masks have been a main ally in containing this epidemic. Many people claim that they cannot filter the virus due to the size of the pore or that they are a “muzzle” that is useless.
When we cough, laugh or talk we produce aerosols. These aerosols are formed of particles in the form of drops of water (1-100 micrometers in diameter), and either evaporate releasing the contagious agent or they reach the recipient. The virus, in the form of SARS-CoV-2 virions, is 0.1 microns.
In masks, the smaller the pores, the better the filtration mechanism, but the more difficult it will be to breathe through them. Mask approval tests are carried out by measuring whether 0.06 micron particles pass through a mask when the flow rate is set at 85 liters per minute, which is equivalent to rapid respiration. Added to this, the masks have several superimposed layers, which sets the possibility of a particle or a virion passing, to less than 0.1%.
For example, the FFP2 and FFP3 masks filter 94-99% of particles with a diameter of 0.06 microns, therefore they are more than enough to decrease the probability that the virus will pass.
It’s just a flu
Fake. No, it is not a flu. On the one hand, we have to say that it makes no sense to compare this virus with the flu, in general. It is highly nonspecific, since there are many flu strains and serotypes, each with a different behavior. Regarding its lethality, that of SARS-CoV-2 is around 2% and that of influenza does not reach 0.1%. In addition, it has been seen that hospitalized patients with covid-19 have a 5 times higher risk of dying than those from the flu.
Additionally, SARS-CoV-2 has been shown to have a tropism for organs other than the lung: kidney, liver, vascular endothelium, and nervous system. Therefore, sequelae have been reported as a consequence of the involvement of these organs. On the other hand, the spread potential of this virus and its ignorance make it much more dangerous than the flu.
5G technology causes covid-19
Fake. There is no scientific proof that 5G technology is harmful to humans. The wavelength at which it propagates does not interfere with our body, our cells, or our DNA. In fact, coffee has more carcinogenic power.
In summary, although different studies are being carried out, depending on the scientific evidence available, we can be calm about this new technology.
Jose M Jimenez Guardeño, Researcher in the Department of Infectious Diseases, King’s College London; Alejandro Pascual Iglesias,, Health Research Institute of the La Paz University Hospital (IdiPAZ); Ana María Ortega-Prieto, Postdoctoral research associate, King’s College London; Javier Cantón, Professor of Coronavirus Biotechnology, International Campus for Security and Defense (CISDE); José Angel Regla Nava, Virologist. Investigating emerging viruses: SARS-CoV-1, SARS-CoV-2 (Coronavirus), ZIKA and Dengue, La Jolla Institute for Immunology and Jose Manuel Honrubia Belenguer, Researcher, National Center for Biotechnology (CNB – CSIC)
This article was originally published on The Conversation. Read the original.
