Common Cold: Viral vs. Bacterial – Understanding the Difference

The common cold is a viral infection. Antibiotics, prescribed to treat bacterial infections, are ineffective in treating colds. Secondary bacterial infections can develop from complications of a cold.

Viruses

• Viruses need a host organism to survive and multiply. When viruses enter a cell, they take it over and reprogram it to reproduce more viruses.

Cold Viruses

• There are over 200 viruses that can cause colds. The National Institute of Health's Medline Plus site states that cold viruses are spread by wiping or blowing a runny nose or by sneezing. Watery nasal discharge that changes to thick green or yellow discharge in two to three days is typical for a cold virus and does not indicate a bacterial infection.

Treatment

• Symptoms typically resolve in seven to 10 days. Over-the-counter medications can ease cold symptoms but will not shorten the duration of the infection. Plenty of fluids and rest can help speed recovery.

Secondary Bacterial Infections

• According to the Merck Manual Home Edition, nasal congestion can block normal drainage in the sinuses and ears. Bacterial infections develop when bacteria grow in these fluid-clogged areas. Thick yellow or green nasal discharge still present 10 to 14 days after the onset of cold symptoms may be due to a bacterial infection called sinusitis, which can be treated with antibiotics.

Antibiotic Resistance

• Attempting to treat a cold with antibiotics is futile and can lead to the development of antibiotic-resistant strains of bacteria. This resistance makes it more difficult to treat bacterial diseases with antibiotics.