Distinguish Bacterial from Viral Infections in Children

Infections can be caused by both bacteria and viruses. It's important to learn how to distinguish bacterial from viral infections.
Distinguish Bacterial from Viral Infections in Children

Last update: 01 March, 2021

There are many viruses and bacteria in our environment that are capable of causing infections, in both adults and children. Often, distinguishing the cause of one of these infections is very difficult, even for specialists. That’s because they’re symptomatically very similar. In this article, we’ll tell you how to distinguish bacterial from viral infections in children.

What are viruses and bacteria?

Both viruses and bacteria are microorganisms capable of causing diseases in people. However, while a viral infection always causes illness, this isn’t the case with bacteria. There are many bacteria that are naturally present in our bodies that perform important functions. An example of this is intestinal flora. 

However, not everything is that black or white. If you don’t control the amount of these bacteria, especially those that are more aggressive, they can also cause different diseases. On another note, scientific advances have made it possible to use certain types of viruses known as bacteriophages as therapy.


Being able to distinguish bacterial from viral infections is especially important when it comes to determining the treatment. While you have to treat bacterial infections with the proper antibiotic, viruses are a different story. Viral infections are usually treated asymptomatically until the body is able to get rid of the virus completely.

Distinguish Bacterial from Viral Infections in Children

Therefore, it’s crucial to quickly determine if your infection is from a virus or a bacteria. This is especially true for bacterial infections, so you can start on antibiotics as quickly as possible. 

Types of bacterial and viral infections

The most common viral infections in children are colds, laryngitis, flu, chickenpox, measles, rubella, mumps, herpes, and mononucleosis. In addition, children often experience gastroenteritis and angina, which tend to be caused by viruses.

As for bacterial infections, the most common in children are scarlet fever, whooping cough, urinary tract infections and otitis. These conditions are very common at that age. Also, there are some diseases that can be caused by both viruses and bacteria. Two examples are meningitis and conjunctivitis.

Lastly, there are some viral diseases that can become superinfected and complicated by bacterial infections. This is the case with otitis and sinusitis.

Distinguish bacterial from viral infections in children

Some of these diseases have a specific cause. For example, scarlet fever is caused by a certain virus. In those circumstances, the diagnosis will be clear and you’ll be able to start the appropriate treatment immediately.

However, with many other infections, it’s very difficult to distinguish bacterial from viral infections. Many of these diseases can cause fever, malaise, fatigue, muscle aches, and other nonspecific symptoms in children. Because of that, it’s very difficult to figure out the exact cause.

In these cases, the specialist will be the one who requests the necessary tests to reach the exact diagnosis. Some of these tests include a blood test with culture to check for the presence of certain bacteria.

Other examples of diagnostic tests can be culture of exudate or mucus, which is the case with respiratory infections. In addition, there are stool cultures which are used to test for gastroenteritis. 

Distinguish Bacterial from Viral Infections in Children

How to prevent and treat infections

For many of these infections, there are vaccines that will prevent your child from getting them. Some examples of these vaccines are for whooping cough and some types of meningitis. Therefore, it’s extremely important to take your child to the pediatrician for their check-ups and to make sure they’re up-to-date on their shots. Remember, some of these diseases can be very dangerous.

However, if you’re sure your child is up-to-date on their shots, and they start to present any symptoms, you should go to the pediatrician so they can make a diagnosis. 

As we’ve already mentioned, most viruses in children will be mild. In addition, you should be able to treat their symptoms with analgesics and antipyretics. In the case of bacterial infections, the type of antibiotic you take will depend on the type of bacteria. This is in addition to symptomatic treatment.

When it comes to distinguishing bacterial from viral infections…

There are so many viral and bacterial infections and they’re all very different. In addition, some of them can be really serious for your child.

Therefore, the most important thing when it comes to avoiding possible infections is to make sure your child is up-to-date on their shots. Also, you should go to a specialist as soon as you notice any symptoms. They’ll be the best person to decide how to act in each case.


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • Olvera DPR, Sanchez FJ, Gutiérrez CC, Zavala MEM. (2002). Patogenia de las infecciones respiratorias por virus. undefined.
  • Vila J, Álvarez-Martínez MJ, Buesa J, Castillo J. (2009). Microbiological diagnosis of gastrointestinal infections. Vol. 27, Enfermedades Infecciosas y Microbiologia Clinica. Ediciones Doyma, S.L.; 2009. p. 406–11.
  • Fernández López A, Luaces Cubells C, Valls Tolosa C, Ortega Rodríguez J, García García JJ, Mira Vallet A, et al. (2001). Procalcitonina para el diagnóstico precoz de infección bacteriana invasiva en el lactante febril. An Esp Pediatr. 2001 Jan 1;55(4):321–8.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.