Diagnosis may be difficult with only a physical exam because mild cases of COVID-19 may appear similar to the flu or a bad cold. A laboratory test can confirm the diagnosis. Learn more about COVID-19 testing.
- Have astronauts really been to outer space or are they simply faking it?
- How do I communicate with extraterrestrial life from another solar system with laser beams to send them a message?
- Why did the Russians use their probe immediately on Venus, but NASA waits days to use ingenuity on Mars?
- Are we alone? Are there humans out there besides us?
- Is space junk a serious problem?