“You know the more things change the more they stay the same
Never and forever just keep comin’ back again
Don’t hold out for tomorrow or hold onto yesterday

The more things change the more they stay the same”

                                                                                     -Bon Jovi

We have all heard the statement before regarding Influenza and Covid-19: Covid-19 is just a  kind of Flu.

But, is Influenza, Covid-19, and the common cold the same, or are they different entities.

Let us get to the bottom of this confusion by first revisiting the common denominator.

The Common Cold

Every one of us has experienced the discomfort of the common cold sometime in our lives. One of the main reasons why children miss school and adults miss work is due to the common cold. On average adults contract the cold 2-3 times in a year while children are more susceptible.

Most people get colds in the winter or spring but it is possible to catch a cold anytime during the year. A cold is considered to be a milder respiratory illness than the Flu. This is the only superficial distinction between the two. 

Symptoms

The symptoms of the common cold usually last from a few days to approximately a week. During the first three days, the person is contagious and could pass on the cold to others. This is the time one should stay at home.

Initially, One usually wakes up to a bout of sneezing or coughing accompanied by an achy, feverish, can’t move a muscle feeling.

The symptoms of a Cold usually begin with a sore throat lasting about a day or two. A runny nose and congestion follow along with a cough around the fourth and fifth days. Although a feverish feeling is common along with body pain, it generally does not manifest as a fever in adults, although it is possible. Children are more likely to have a cold accompanied by a fever. 

During a cold, the nose secrets watery nasal secretions for the first few days. These may become thicker and darker in due course before stopping. Some people could experience headaches during this time.

Recovery for most is within 7-10 days. The exception is people who have a weakened immune system, asthma, or existing respiratory conditions. The illness, if not cared for promptly, could progress to serious conditions such as bronchitis or pneumonia.

Causes

This is where it gets tricky. Other than a cold being an ailment by itself; a cold, with all its symptoms, could be a starting symptom of several other ailments. These could include allergies, sinus infections, bacterial infections, and even hay fever. This is the first point that needs to be determined and is the very reason why it is called the common cold as it is a generic symptom for many infections.

When regarding the cold as a stand-alone ailment, it is understood that many different respiratory viruses could cause the common cold. The most common is the Rhinovirus. These viruses can also trigger asthma attacks and have been linked to sinus and ear infections. Other viruses that could also trigger colds include the respiratory syncytial virus, human parainfluenza viruses, adenovirus, common human coronaviruses, and human metapneumovirus.

Watch: The Cold Video

Alarm Bells

Currently, there is no test for the common cold and no specific treatment. It just needs to run its course and most people get better after a few days of rest and recovery. Over-the-counter medications may reduce the intensity of the symptoms but would not get rid of the cold any faster.

Remember: Antibiotics do not work against viruses and would not help in the recovery against a respiratory virus. Overuse of antibiotics could lead to a tolerance that would prevent them working against a bacterial infection.

The matter needs a more serious approach if the symptoms are abnormally severe and /or last more than 10 days without any signs of reducing in intensity. If there is excessive lethargy or a very high fever.

Any child less than a year should also be taken to a doctor without any delay. 

The FLU

There are times when we have experienced a cold that does not seem to let up even after 10 days of sniffing and snorting. The body pain is severe and every movement is a task and a deterrent to movement itself.

This could be a case of the FLU.

So What is it?

The Flu is an illness that has similar symptoms to that of the common cold. However, the cause of this ailment is a specific virus: The Influenza Virus.

Hence, the abbreviated name ” The Flu”

The flu is the most familiar respiratory infection in the world after the common cold. Approximately 25 to 50 million people contract influenza each year, just in the US alone. Seasonal influenza viruses are detected year-round but cases of the flu are most common during the fall and winter. The flu season has no consistency from year to year, but it has been observed that, in the United States, influenza activity often begins to increase in October. Most of the time flu activity peaks between December and February, although significant activity can last as late as May.

Most tropical countries in Asia, such as India, exhibit influenza seasonality that coincides with the monsoon season, from June–October.

Although there are influenza-related deaths, they are majorly caused by complications of the flu rather than the actual influenza virus.

Symptoms

The symptoms of the flu tend to be more severe than that of the common cold. They also start abruptly and develop more rapidly.

Children sometimes experience gastrointestinal discomfort, like belly pain, nausea, vomiting, or diarrhea. For most adults, though, these symptoms are not caused by the influenza virus but some underlying illness. This is sometimes inaccurately referred to as the “stomach flu”.

Complications from the Influenza virus, such as bronchitis and pneumonia, can also occur and are common among the elderly, young children, and anyone with a suppressed immune system.

Cold OR Flu?

How would you know if you have the cold or the flu especially since the symptoms are similar?

-Take your temperature, say most experts. The reasoning behind this advice is that the common cold rarely has symptoms of fever above 101 degrees.

The more sure-fire method would be to test for the influenza virus.

Some general observations of the symptoms are listed below as a guide:

the virus

Influenza viruses are categorized into four types: A, B, C, and D. These types are antigenically* distinct from each other.

* {Antigenic Shift and Antigenic Drift

Re-assortment is the swapping of gene segments between influenza viruses. This can occur when two influenza viruses infect a host at the same time and swap genetic information.

An Antigenic drift is said to have occurred when there is a series of minor genetic mutations.

An Antigenic shift involves the “mixing” of genes from influenza viruses from different species. Pigs, birds, and humans.

This results in new Strains of the virus that could be more deadly than the original, and there is no going back.

An epidemic or a pandemic occurs when a new and different virus emerges, that both, infect people and spreads rapidly among people}

Influenza A and B viruses cause seasonal epidemics of the disease commonly known as the flu season. However, there is a stark difference between the two.

Influenza A viruses infect a variety of animal species including humans.

The influenza B virus is normally found only in humans. 

The Influenza A virus is the most susceptible to an antigenic shift/ drift due to the possibility of transfer between species. This results in multiple strains in a single host, facilitating mutations and the mixing of genes, giving rise to a new strain novel to humans. Thus, the Influenza A viruses are the only influenza viruses known to cause flu pandemics, i.e., global epidemics of flu disease.

The Influenza B virus, which normally is only found in humans, is responsible for many localized outbreaks and epidemics.

Influenza C virus infections generally cause mild illness and are not thought to cause human epidemics. They are also  generally non-symptomatic, so are of little medical concern.

Influenza D viruses primarily affect cattle and are not known to infect or cause illness in people.

The Name

Two types of spikes cover the surface of the Influenza A and B viruses.

The haemagglutinin (H) and the neuraminidase (N)

Influenza A viruses have 17 different types of haemagglutinin, from H1 to H17. And,

Nine different types of neuraminidase, from N1 to N9.

Each virus has one type of H and one type of N.

Thus, the H1N1 influenza virus, for example.

Influenza pandemics

The exposure of people to a virus determines their future protection from it. This could be via direct exposure through infection or from a vaccine for that virus. The immune system on exposure creates virus-specific antibodies that will neutralize the virus when it next enters the body.

But here is the catch.

Influenza viruses mutate rapidly. A new strain results every few years from the mutation of the virus. A person exposed to a related strain of a virus will have pre-existing antibodies created by their immune system and the resultant illness would be mild. 

There eventually comes a time when the change in the genetic makeup of the virus is so great, that it produces a strain so different from the others before it, that humans have little or no preexisting immunity. This antigenic shift can result in widespread, serious illness. The global spread of this new influenza virus strain causes an Influenza pandemic.

In the 20^th century, three influenza pandemics occurred. They were caused by the antigenic shift in influenza A strains.

Spanish Influenza 1918-19

This pandemic is the one against which all other pandemics are measured.

The reason is that none that have followed has claimed as many lives as the Spanish Influenza. 40 million people are believed to have succumbed to this illness across the globe. Some estimates put total deaths closer to 70 million. 

Scientists have classified the virus as H1N1 influenza.

Asian Influenza 1957-58

After the 1918 pandemic, the flu was here to stay and remained a yearly occurrence. There was, however, no new infectious strain of the influenza type until early 1957.

A serious wave of flu was cutting a path through China in February of 1957.  Some older people who had survived the influenza pandemic of 1889-1890 showed an antibody response to the new virus.

It was soon determined that most people lacked antibody protection from the new influenza virus.

This was named the H2N2 type and had a body count of about 2 million people.

Hong Kong Flu 1968-69

The first signs of a new influenza A strain emerged in Asia, just like the one 10 years earlier, albeit this one originated in Hong Kong. 

Around 1 million people worldwide succumbed to this strain of the influenza virus. The virus was very similar to the H2N2 influenza virus. This was because the Hong Kong virus shared the N component with the Asian virus.

This similarity could have been the reason why people were more protected from its effects due to the presence of pre-existing antibodies.

The virus was named H3N2.

Avian Flu Threat 1997-Present

This strain did not blow up into a pandemic but the fear was present at the time of its discovery. This originated out of Asia, once again. The Avian influenza, infected birds and then spread to humans. Several humans became ill and died from the virus.

However, there was a lack of human-to-human transmission which limited the spread and contagiousness of the strain. The death toll was between 400-500 people.

This strain was named H5N1.

Novel H1N1 2009

For a change, the next outbreak of Influenza and the first of the 21st century originated in Mexico.

The virus was named H1N1, and nicknamed the Swine Flu.

Yes, the same name given to the virus responsible for the most devastating influenza pandemic in history. So, was this the same virus returning to haunt the population of another century, or is there a twist in the story?

Was the 2009 H1N1 the result of antigenic shift or antigenic drift?

The origin of this virus is said to have been from pigs, which then made the jump into humans. So the hypothesis of an antigen shift or an antigen shift is quite plausible, right?

Well, it seems that this is not the case as the was no change in the H and N components of the virus. This was against the very definitions of antigenic genetic mutations of the virus as both or either one of these components would change in the new resultant strain.

This remains a grey area in Virology.

Read more on Influenza

Coronavirus

Who has not heard of SARS-CoV-2, the cause of the disease known as Covid-19?

This coronavirus has been the talk of the town for the past year and a half. It has caused fear and confinement among the populations of the world and resulted in a death toll only surpassed by the Spanish Flu that occurred over 100 years ago.

Since the term “novel coronavirus” is firmly inscribed in our minds, it would come as a shock to the uninitiated to know that most of us will be affected by a coronavirus at least once in our lives.

The word “novel” used in the context of the virus does not deduce that the coronavirus is something new that has only just been unleashed into the world. It infers that it is a new, never encountered before, strain of a coronavirus.

What’s the difference, you say?

-Well, the point is that coronaviruses didn’t just turn up out of the blue. Coronaviruses (CoVs), a large family of different single-stranded RNA viruses, have existed for a long time and cause a smorgasbord of illnesses from mild cough to serious respiratory illnesses. 

The “new or novel” coronavirus that causes Covid-19 is one of several that infect humans and has existed in the animal kingdom for a long time. Sometimes, due to proximity and unhealthy interaction, the virus jumps over to humans. This is one of the hypothesis about the origins of this virus being the wet markets of Wuhan.

So, this virus is not new to the world, it is new on the list of those that infect humans.

In fact, scientists first discovered a coronavirus in chickens in the 1930s.

A human coronavirus was first discovered in 1965. It caused a common cold.

Types

Coronaviruses (CoVs) are the largest known group of RNA viruses.

CoVs are divided into four genera:

alpha-coronavirus,

beta- coronavirus,

gamma-coronavirus, and

delta-coronavirus

Furthermore, To date, six Human coronaviruses (HCoVs) have been identified.

Two, alpha-CoVs:              HCoVs-NL63 and HCoVs-229E

And,

4, beta-CoVs:               HCoVs-OC43, HCoVs-HKU1,

                                                                                 Severe acute respiratory syndrome-CoV (SARS-CoV)

                                                                                Middle East respiratory syndrome-CoV (MERS-CoV)

New coronaviruses emerge from time to time in humans due to the variety and wide distribution of coronaviruses, the genetic diversity created due to the ease of their mutations, and in recent times, mainly due to the unethical, unhygienic, and often barbaric increase of human-animal contact and eventual animal consumption.

Contagion

How contagious a virus is and how quickly it can spread across the general population is expressed in terms of a numerical value.

R0-pronounced “R naught”: is a mathematical term that indicates how contagious an infectious disease is. It’s also referred to as the reproduction number.

So, a virus with an R0 value of 3 would mean that every person infected with the virus has the capability to infect 3 more people with the virus. This is a non-linear increase in the number of infected and can reach immense proportions in a short time.

The R0 value for Sars-CoV-2 is between 3-5.

Past Outbreaks

As mentioned, seven human coronaviruses have been identified. In order for them to be discovered and identified they would have to infect humans.

Two, alpha-CoVs: HCoVs-NL63 and HCoVs-229E, and, two beta-CoVs: HCoVs-OC43 and HCoVs-HKU1,

did infect humans but the severity, the spread, and resultant loss of lives were not significant enough to term them as a major epidemic let alone a pandemic.

SARS

The first major coronavirus outbreak occurred in  November 2002, originating from Guangdong Province, China, which rapidly progressed to Hong Kong, Beijing, Singapore, Vietnam, and Canada by March 2003.

It took until the genome of the virus to be identified by the Canada’s National Microbiology Laboratory in 2003 for the cause of the outbreak to be confirmed. Sars is very similar to COVID-19 and the viruses are even named Sars- CoV, and Sars- CoV- 2 respectively.

Older people were more susceptible to suffering from a severe disease. Symptoms included fever, cough, muscle pain, and sore throat. Due to the high mortality rate, however, there was a much greater chance of dying if you had Sars.

SARS quickly spread to 26 countries before being contained after about four months. More than 8,000 people fell ill from SARS and 774 died. Since 2004, there have been no reported SARS cases.

MERS

A decade later, in 2012, there was another outbreak involving a newly identified coronavirus.

The first case of the Middle East Respiratory Syndrome (MERS-CoV) outbreak, on the other hand, was first reported from Jeddah, Saudi Arabia in September 2012.

MERS is a viral respiratory disease that has since spread to 27 countries, according to the WHO. People contracting the virus develop severe acute respiratory illnesses, including fever, cough, and shortness of breath.

Two further Mers outbreaks occurred since then:

South Korea in 2015 and Saudi Arabia in 2018. There are a handful of Mers cases every year, but the outbreaks are well contained.

Since its emergence in 2012 till date the WHO confirmed 2,578 MERS cases and 888 deaths.

Read: A brief history Of CoV

                      Where does CoV come from?

Why didn’t Sars and Mers result in pandemics?

This has everything to do with the “R Naught” values and the severity of symptoms.

Both Sars and Mers have a higher mortality rate than Covid-19, however,

The R0 value for Mers is <1. It is not very contagious. The cases reported were from those exposed to very close proximity hosts like family or infected camels. Thus, it was contained effectively.

Both Sars- CoV, and Sars-CoV-2, being similar, have an R0 value of anywhere between 3-5. with 5 being the more recent estimate. this means that every infected person has the capacity to infect 5 people. This is highly contagious. The difference between the two lies in the symptoms.

Sars produced symptoms that were more severe, so it was much easier to identify and isolate patients.

With Sars-CoV-2, on the other hand, symptoms can be very mild – some people may not even show any symptoms at all – but can still infect other people. This made identifying carrier hosts and isolating them very difficult. Although, not as deadly as either Sars or Mers, but because it can spread undetected, the numbers of people it will infect and the resultant global spread is much worse.

This is how the pandemic came to “still” pass.

Symptoms of Covid-19 

Other than those who are asymptomatic and those who may have been additionally infected by cold/flu viruses, The basic symptoms of Covid-19 are the same as the common cold and the Flu.

Yes…It is possible to be infected by multiple viruses.

There is just one exception: Change in or total loss of taste or smell is more pronounced with Covid-19.

The only way of knowing for sure is by testing: And, we know that is debatable.

Complications

Complications arising from a Covid-19 infection are a cause for concern. Sars-CoV-2 can cause different complications from the flu, such as:

Blood clots in the veins and arteries of the lungs, heart, legs, or brain.

and  Multisystem Inflammatory Syndrome (MIS-C )in children and (MIS-A) in adults.

Read: CDC on Flu and Covid

In Conclusion:

It is not surprising that Covid_19 has been incorrectly and often confused with the Flu. The symptoms are the same and differ only in severity, and that too is not consistent. Sometimes there may be no symptoms at all. The ground zero feeling for all laymen would be that of a severe Flu, until and unless complications set in. Till then the difference is pretty much indistinguishable.

But are they the same? no, they are not.

Are they different? not so much, if you only consider initial symptoms.

I guess,

The more things stay the same: The more they change