Coronavirus: Loss Of Taste & Smell

The Covid-19 pandemic has changed the way people go about their daily lives. Since the initial announcement of this viral infection, we have observed a significant spike in cases.

According to the WHO, by the 12th of January, 2020, a total of 89,416,559 confirmed cases of the Covid-19 infection had been reported. 

With a rising death toll and covid-19 cases, people are becoming more concerned about being infected themselves. Even though breakthroughs have been made in terms of a coronavirus vaccine, we still have a long way to go before the population has been immunized.

Learning about the symptoms of coronavirus is essential. This ensures covid patients take action and isolate earlier, helping to reduce the spreading. 

Is A Loss Of Smell Or Taste An Early Symptom Of Covid-19?

The average person greatly relies on their sense of smell and taste daily. While not essential to human survival, it allows a person to thoroughly enjoy a meal. It is also a useful sensory function that can help in identifying potentially dangerous substances. 

Some people who received a covid-19 diagnosis reported a reduced smell or taste. In some of these individuals, there was a complete loss of smell or taste. In some cases, the patient finds that they only lose their sense of smell or their ability to taste. In other scenarios, however, both senses may be affected. 

Covid-19 is not the only infection that can lead to problems with these senses. There are other types of upper respiratory infections that can lead to olfactory dysfunction, as well as other issues with sensory neurons. 

However, with the coronavirus disease having such a widespread impact, event a slightly altered smell may cause people to start panicking. 

It does seem like sensory dysfunction remains a common symptom among people with Covid-19. 

It should be noted in asymptomatic patients, a loss of taste or smell has been reported. This may serve as an indication that the patient has Covid-19 without their awareness. By identifying this as an early symptom, the patient can obtain appropriate testing and practice isolation techniques. The virus that causes Covid-19 infections can spread even if a patient is asymptomatic – making the early discovery of the disease more crucial. 

In terms of an early symptom associated with Covid-19, some studies have provided evidence that this may be the case. In one study, researchers analyzed 13 records. In total, there were data related to 11,054 Covid-19 cases involved in these records. The study specifically looked at the prevalence of sensory problems among these patients. 

Among patients with Covid-19, up to 64.5% reported a loss of taste or smell prior to experiencing other symptoms associated with this disease. 

How Can Covid-19 Result In A Loss Of Smell Or Taste?

Many individuals wish to understand why sensory function in their mouth and nose are adversely affected by the Covid-19 infection. Unfortunately, at the moment, the evidence seems to be limited. Only theories have been shared thus far, with no specific evidence on why this happens. Still, we can turn our attention to these theories, as they were suggested by experts in the field. 

Researchers currently suggest it is the effect that the SARS COV 2 infection has on cells in the nasal cavity that causes a loss of smell. It has been found that the virus that causes Covid-19 attaches to ACE2. This is a protein in the body. The protein can be found on the surface of certain cells. The SARS COV 2 virus binds to this particular protein, which then allows it to use the cell as a host. 

A significant number of ACE2 proteins can be found among cells that make up the oral and nasal cavities. Researchers explain that the virus may cause an invasion of specific nerve cells linked to the body’s ability to smell and taste. 

This is one pathway that researchers have suggested, but there are limitations in the current theory. 

In one study, however, things did not completely check out when looking at this theory. This study found that there are no ACE2 proteins to be found on nerve cells involved with sensory functions. This means that the virus does not directly attach nerve cells that allow a person to taste or smell. 

Researchers did, however, find that this theory may still be how coronavirus contributes to olfactory loss. The novel coronavirus infection picks cells around these nerve cells as hosts. These cells may be found in the olfactory epithelium. The olfactory bulb also hosts such cells. 

The explanation could be that the infected cells suffer inflammation. When this happens, the inflammation causes damage to the nerve cells involved in these two sensory functions. Note that this does not directly relate to taste dysfunction, but only a loss of smell. 

Some studies have also revealed a strong connection between taste and smell. In some cases, patients who lose their sense of smell may find that their taste is affected. Thus, when inflammation surrounding the olfactory nerve cells causes problems with sensory functions in terms of smell, this can lead to complications with taste.

Researchers have provided evidence to back up these claims. It is currently the strongest evidence that explains the loss of taste in patients with Covid-19. 

How Common Is This Symptom?

Some studies have considered the frequency at which these sensory problems occur in patients with Covid-19. Studies note that the frequency seems to be relatively similar to the incidence of reduced olfactory function among patients with normal cold or flu. 

The prevalence of sensory problems among patients with Covid-19 seems to be mixed. In some studies, there is a high prevalence. On the other hand, a number of studies have found the frequency to be less significant. 

In one study, previous trials and surveys were considered. Results for the incidence of smell and taste loss among Covid-19 patients varied between 12% and 89%. The loss of taste seemed to be a more common problem among the patients. There was also a high incidence of the two issues combined. 

Other studies have also been conducted to provide a more accurate view of the prevalence of sensory dysfunctions among these patients. A study led by Universities in China considered the relationship between anosmia and Covid-19 specifically.

Anosmia is a term that refers to problems with a person’s ability to smell. Some patients only experience a partial loss of smell. In other patients, a complete loss of smell may be noted. 

The study found that anosmia seems to be more prevalent in female patients compared to men. The study showed that up to 68% of patients with Covid-19 would experience olfactory sensory neurons problems. When olfactory neurons are affected, the sense of smell may be affected too. 

How To Test Your Sense Of Smell And Taste

While it is important to avoid jumping to conclusions in some cases, the coronavirus’s severity has taught the population to practice caution. Since early detection of symptoms and the virus can reduce the risk of spreading, it is crucial for people to note anything that may signal Covid-19. This would include a loss of their smell and taste. 

Some individuals may not be completely sure if they are losing these sensory functions. With this in mind, doing a few smell and taste tests can be helpful. Once these tests have been performed, it would be easier for a person to understand whether they may be experiencing these symptoms. 

Due to connections made between smell and taste, it would be a good idea to start with a test of olfactory function. This essentially means trying to smell a few different things and see if they can pick up on the various scents. 

Below are a few ideas to help in testing smell:

• Foods that contain characteristic smells should be used. These foods should also preferably have a strong aroma. 
  
  
• Coffee beans are great for smell testing. A person may also consider trying to smell some fresh garlic or cinnamon powder. 
  
  
• It is not essential to use food. A scented candle can be lit – the individual then tries to pick up the scent of the candle.

Once the smell test is done, another test for taste should be done too. A few tips to help with testing a person’s ability to taste:

• It is advisable to stick to food and edible items when testing taste senses. 
  
  
• Consider trying out different types of foods. It would be ideal to consider a diverse selection of characteristics. 
  
  
• Try eating sour fruit like a lemon, and drink some coffee with no sugar added. The person should consider if they are able to taste the bitterness. For something sweet, a piece of chocolate can work. A salty snack is also a good idea to further test the sense of taste. 

When the person cannot pick the scent or flavor during these tests, they may be experiencing dysfunction in the related sensory neurons. This does not necessarily mean a Covid-19 diagnosis will be made, as other factors can also lead to a loss of smell. 

Still, it is important for patients to be able to recognize the presence of this infection. Those who experience a sudden onset of these symptoms should be concerned. This is rather common among patients diagnosed with Covid-19. In such a case, getting tested is a good idea. It is also important to look out for other symptoms associated with Covid-19.  

The loss of taste or smell can last for a while in a person with Covid-19. The duration may differ from one patient to the next. In most cases, a person will find that these senses have a dysfunction for a longer period compared to the flu or a cold. 

With the usual flu, reduced senses tend to last for about three days but can sometimes go on for up to a week. In people with Covid-19, these symptoms only start to subside after eight days. A European study revealed that some people experience a loss of taste and smell covid-related symptoms for as long as 28 days. 

What Other Symptoms Should You Watch Out For?

While a patient may lose their sense of taste and smell early on during a Covid-19 infection, this is not the only symptom that may develop.

Individuals also need to be aware of other symptoms that signal the presence of this infection. Additionally, some people may experience other symptoms but still be able to smell and taste without any problems. 

Certain symptoms associated with the Covid-19 infection tend to be more common than others. This is especially among people with a mild case of the illness. 

Symptoms that people should look out for include:

• Breathing difficulties may occur as Covid-19 infects the upper respiratory tract.
  
  
• Coughing is to be expected. 
  
  
• A high fever is another symptom to consider. Some people also experience chills. 
  
  
• Fatigue is very common in patients with Covid-19. The individual may feel tired and weak during the infected period. 
  
  
• Some people complain about a sore throat. 
  
  
• Headaches can develop while the infection is active. Some people also find that their body suffers from general aches. 
  
  
• Nasal congestion is also a possible symptom. This causes nasal obstruction, which can further contribute to nasal symptoms and breathing difficulties. It is also possible to have a runny nose. 
  
  
• There are a few digestive symptoms that can develop too. Some people report that they experience diarrhea. Another common digestive symptom includes nausea. Additionally, some people may vomit. 

Individuals need to ensure they understand when medical assistance will be required. Many individuals are able to effectively recover from Covid-19 at home. This, however, is not the case with all individuals who become infected. 

Those with existing diseases that alter the immune system’s ability to ward off viruses need to be cautious. Individuals with diabetes, heart disease, and chronic obstructive pulmonary disease should also ensure they obtain medical care if they have Covid-19. 

Obesity has also been linked to a higher risk of complications associated with this viral infection. The excessive weight in the body contributes to numerous chronic diseases and can also impact immunity. 

What Else Can Cause You To Lose Your Sense Of Taste Or Smell?

When talking about a loss of smell or taste at the moment, the first thing that comes to mind is Covid-19. This is caused by the quick rate at which the viral infection is spreading.

People need to understand that losing these sensory functions does not guarantee they have been infected. Some other conditions and factors can also contribute to a reduced function in these sensory neurons. 

With this in mind, people need to consider their own situation. The individual should look at factors in their own life that may be contributed to a loss of taste or smell. When such factors are identified, it is important to take note of the accompanying symptoms. If additional symptoms are also experienced, it may be a good idea to isolate and get tested if needed. 

Other than a loss of taste and smell as a Covid-19 symptom, other problems that can cause these symptoms include:

• Smoking cigarettes can interfere with both smell and taste. Thus, individuals who smoke may experience a gradual loss in their sense of taste and smell. 
  
  
• Allergies are known to cause inflammation in the nasal cavity. In turn, this may affect sensory neurons in the area. 
  
  
• Individuals with nasal polyps are also at risk of experiencing a reduction in their ability to pick up scents. 
  
  
• Certain neurological conditions cause problems with nerves. This can create problems with communication between nerves. Parkinson’s disease and Alzheimer’s disease are examples of such conditions. People with multiple sclerosis may also find that nerves in the nasal and oral cavities are affected. 
  
  
• People who suffered a head injury are at risk of losing their sense of smell or taste. 
  
  
• Some medications can cause these symptoms. Examples of medications associated with poor smell or tests include antihistamines, antibiotics, and prescription drugs used for hypertension. 
  
  
• People who undergo radiation treatment in the neck or head are at risk. 
  
  
• Cushing’s syndrome and hypothyroidism can lead to these problems.

In addition to these causes, some people who are exposed to solvents and chemicals may suffer damage to the nerves in their nose. When this happens, the patient could experience similar symptoms. 

Many of these causes tend to create a gradual decline in smell and taste. With Covid-19, the onset of the symptoms will usually be much more rapid. This is one way for a patient to determine whether Covid-19 might be the issue – especially if the person had not experienced such symptoms in the past. 

Conclusion

Covid-19 patients may experience several symptoms. The severity and specific symptoms experienced may differ between patients. In some cases, the virus causes more serious symptoms – and may even lead to death. Even in mild cases, some people experience problems with sensory neurons. This can lead to smell loss and taste loss in the patient. Recognizing mild symptoms at an early stage can help reduce the transmission rate. 

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