Number of tests for COVID-19 in most impacted countries worldwide as of Dec. 2022

As of December 22, 2022, the United States had performed around 1.15 billion tests for COVID-19, the highest number of any country worldwide. Russia has conducted over 273 million tests.

High demand leads to testing problems

The COVID-19 pandemic has put health systems around the world under severe strain. Towards the beginning of the pandemic there was a huge demand for test kits, but production capacity was stretched thin. In the United States, faulty diagnostic kits produced by the Centers for Disease Control and Prevention meant the early spread of the disease went undetected for weeks. Elsewhere, concerns were raised regarding the accuracy of some rapid diagnostic tests (RDT). In April 2020, officials in India canceled a large order of test kits due to a low accuracy rate.

What are rapid diagnostic tests?

Widespread coronavirus testing has helped to track the spread of the disease. RDTs are a point-of-care test that can deliver results in around 30 minutes – more traditional diagnostic tests conducted in laboratory settings are more time consuming but provide greater reliability. One type of RDT detects the presence of antibodies in a patient’s blood sample. Immune system cells produce antibodies to fight pathogens, and the detection of them may mean the patient has developed some natural immunity to the virus.