A viral culture is a test to find viruses that can cause an infection. A sample of body fluid or tissue is collected and added to certain cells used to grow a virus. If no virus infects the cells, the culture is negative. If a virus that can cause infection infects the cells, the culture is positive. The type of virus may be identified using a microscope or chemical tests. Sometimes other tests are done to find the right medicine for treating the infection. This is called sensitivity testing. Not all types of viruses can be grown in a culture.

A viral culture may take several weeks to show results.