Medical Q&As

Bacteria and viruses?

What are the differences between bacterial and viral infections? If a swab test were done would it test for both?

Bacteria and viruses are both microorganisms, which means that they are tiny living creatures that cannot be seen without the aid of a microscope. The symptoms of infection can be broadly similar for both types of infection. For example bacterial and viral meningitis cause similar symptoms albeit the prognosis for the latter is far more serious. Most of the common respiratory infections of childhood are viral in origin. One important practical difference between bacteria and viruses is that antibiotics are ineffective against viruses, which means that it is a complete waste of time and money to use them in cases of uncomplicated viral infection. A swab test would not test for both types of micro organism. Tests for detecting viruses are sent to the virus reference laboratory whereas bacterial swabs are dealt with in a hospital microbiology department. If you wanted to test for both you would have to take two samples and send them to two separate units. Some bacteria also require special transport media to sustain them for the journey to the laboratory otherwise laboratory testing would be unsuccessful. There are several different types of swab and many kinds of transport media and containers for biological specimens. There is no simple multipurpose universal swab that can be used for every eventuality.