The common cold and flu are respiratory ailments caused by viral strains in the body. While both of these illnesses are contagious, the length of time that people are contagious with them varies
How long are you contagious with a cold?
Common colds affect millions every year and may last for up to 10 days.
The seasonal cold is one of the most common respiratory sicknesses in humans. According to the Centers for Disease Control and Prevention (CDC), there are millions of cases of the common cold each year in the United States alone.
The symptoms of the common cold are caused by the body's response to the virus rather than the virus itself. Most cases of common cold are spread through sneezing, coughing, and people touching contaminated surfaces. This suggests that people are most contagious once symptoms appear.
As the symptoms of the cold begin to reduce, the risk of spreading the illness goes down, though the risk is still there. The average cold lasts anywhere from 3-10 days, so people should expect to be contagious during that period.
There are a couple reasons for the common cold's widespread reach. The symptoms of the cold are caused by a large number of different viral strains, such as rhinoviruses, adenoviruses, and coronaviruses. It is nearly impossible for the body to build up resistance to all of these viral strains at once.
The viral strains also adapt to their environment and they have learned to do this to survive the human immune system.
How long are you contagious with the flu?
The influenza virus, also known as the common flu, is a highly contagious respiratory virus that affects all age groups. The virus has a different effect on every person, and symptoms can range from mild to life-threatening. There are millions of cases of the flu virus each year.
Viruses spread through a process called viral shedding. When a virus such as the flu duplicates itself in the body enough to cause infection, it starts to send out extra viral cells to look for a way to infect others.
These cells are released in a number of ways, such as mixing with the mucus and saliva that finds its way back into the open environment.
A study posted to The Journal of Infectious Disease found that most of this shedding occurs during a 2-3 day period after symptoms appear. Only 1-8 percent of contagiousness occurs before the symptoms.
The main difference between the flu and a cold is in the symptoms. Flu symptoms are more severe than those caused by a cold and affect the whole body. The common cold typically just affects the upper airway.
Like with the common cold, it is still possible to spread the virus during the entire time the flu symptoms are present. Most flu symptoms last from 2-10 days. People can expect to be contagious during that entire period.
Another reason the flu is so contagious is that it continually evolves. Normally, when the body gets over an infection, it remembers how to fight off that particular virus. Because the flu virus is constantly evolving, the body is rarely dealing with the same flu virus twice. This leads to some people contracting the flu year after year.
How to stop cold and flu from spreading
Covering a sneeze may prevent the cold and flu viruses from being spread.
The most important factor in reducing the spread of viral infections, such as the cold and flu is to create healthful habits during the cold and flu season.
Drinking plenty of water, eating a healthful diet, and getting plenty of rest are advised. These simple practices can help to make the time spent with the illness as comfortable as possible.
When symptoms are showing, there are a few steps that people can take to protect others from catching the illnesses:
- Covering a cough: When people cough or sneeze, it is important to cover the mouth and nose with a tissue or the elbow of a sleeve if no tissue is available. The spray of saliva or mucus caused from a cough or sneeze contains the viruses that may increase the risk of spreading.
- Getting rid of tissues: If possible, people should throw tissues away immediately after use. Using a new tissue each time decreases contact with the virus and keeps hands as clean as possible.
- Washing frequently: Reducing the spread of the cold and flu virus can be as simple as washing hands frequently, especially after coming into contact with bodily fluids. If it is impossible to wash hands frequently, people should try to avoid direct contact with other people or public items like telephones and door handles.
If symptoms are difficult to manage properly, some people choose to stay home from work or school and opt out of social activities. This helps prevent the spread of illness while also taking care of personal well being.
Symptoms of the common cold
Once they infect the body, viruses spread rapidly. As the immune system responds to eliminate the common cold virus, the symptoms of the common cold appear.
While the effects of a common cold are usually mild and go away on their own, the symptoms can be very annoying. Symptoms of the common cold include:
- sore throat
- congestion in the nose and sinuses
- runny nose
- hoarseness of voice
For a small number of people, the common cold also increases the risk of other illnesses entering the body. These illnesses include ear infections and more serious respiratory illnesses such as pneumonia.
Symptoms of the flu
The symptoms of flu are similar to those of the cold, but are typically more intense than the common cold. Symptoms of the influenza virus typically include:
How do approaches differ for treating the two illnesses?
Both the cold and flu cause symptoms that can disrupt daily life. In most cases, the viral strains run their course relatively quickly without any treatment.
Many people find relief from treating the symptoms of the illnesses, however. There are many drugs used to treat the symptoms of the cold and flu, which are available over-the-counter or online. These medications may be useful if severe symptoms make it difficult to function normally.
In some cases of influenza, doctors may prescribe antiviral.
The flu vaccine may help to reduce the risk of contracting the flu.
Some people choose to take preventive action toward the flu in the form of flu vaccines. Creating a vaccine for a virus that is constantly evolving is no easy feat. The CDC report that vaccine reduces the risk of contracting the flu by 50-60 percent if the vaccine is suitable for the particular type of virus that is circulating.
There are many other factors that affect the level of effectiveness of a flu vaccine, but the CDC believe that having the flu vaccine is the best way to prevent the flu.
There is a common belief that the flu vaccine can cause the flu. It cannot. Some people may have an achy arm the next day, have been developing symptoms of another virus, or already had the flu. The way the vaccine is made means that people can't actually get the flu from the flu shot.
In most cases, treating the symptoms of the virus and taking steps towards healthful habits can help prevent the spread of illness.