Bacterial vs. Viral Infections -

Do You Know the Difference?

What is the difference between a viral and a bacterial infection?

Both viral and bacterial infections will make you feel sick and they share many of the same symptoms. But, did you know that:


a cold or flu virus usually lasts only up to 10 days while illnesses caused by bacteria usually last more than two weeks?

cold and flu symptoms - runny noses, watery eyes, dry coughs, sore throats, chills, aches and pains - are caused by viruses, not bacteria?

adults who have a sore throat without significant fever most likely do not have a bacterial infection, such as strep throat? - their disease is more likely to be caused by a virus.

most coughs do not need an antibiotic?

REMEMBER - If your symptoms suggest a viral infection, antibiotics won't help. Your doctor or pharmacist will be able to recommend medications to help you feel better while the virus runs its course.

Do I have a bacterial infection?

The following signs and symptoms, usually lasting longer than two weeks, suggest a bacterial infection:


a high, persistent temperature

a thick, coloured discharge from your nose

a chronic cough

REMEMBER - Antibiotics should only be used when they are truly needed - to cure a bacterial infection.

There are two types of germs that cause most infections in the United States - viruses and bacteria.


Virus - viral infections include

All colds and flu

Most coughs

Most sore throats

Usually involve several parts of the body


Antibiotics CANNOT KILL viruses

A virus is an infectious agent, smaller than bacteria, which requires the cells of a living organism to grow or reproduce. Viruses cause a variety of infectious diseases, among them the common cold, diarrhea, chicken pox, yellow fever, most childhood respiratory diseases and the majority of infections of the upper respiratory passages.


Bacteria - bacterial infections include:

Strep throat

Urinary tract infections

Most ear infections

Some sinus infections

Are usually localized at a single point in the body


Antibiotics CAN KILL bacteria IF the bacteria are not resistant

Bacteria are minute life forms which can cause infections in humans. Bacteria have the ability to adapt quickly to their surroundings. Their goal is to survive and multiply. This ability to adapt to their surroundings is the basis of antibiotic resistance. Surviving contact with that antibiotic allows the bacteria to resist it in future contacts.

Antibiotics are not effective for the common viral illnesses of childhood, such as colds, most coughs and bronchitis, croup and non-strep sore throats. Over prescribing of antibiotics is the leading cause for the emergence of resistant bacteria. Parents should understand the difference between viral and bacterial infections, talk to their clinician about the specific cause of any infection, and not pressure for antibiotics. Their child may well be better off without them for many illnesses.

Viral Infections

Bacterial Infections

Usually involve various parts of the body: sore throat, running nose, headaches, muscle aches and fever, nausea, diarrhea.

Usually "localized" in a single area of the body: very sore throat, ear pain, dark phlegm-producing cough, painful sinuses with colored mucus, painful urination.
Typical viral infections: cold, respiratory flu, stomach flu.

Typical bacterial infections: strep throat, ear infection, pneumonia, sinusitis, bladder infections.

Antibiotics do not help.

Antibiotics do help. It is important to take the antibiotic on time and until the medicine is finished unless you break out in a rash. Then stop the medication immediately and call the practitioner.

Rest, fluids and symptomatic relief do help. Neglecting these may lead to a secondary bacterial infection.