Save your business while saving lives,

NEW YORK (Reuters) - After a week or so sick in bed in their New York City apartment in March, members of the Johnson-Baruch family were convinced they had been stricken by the novel coronavirus. Subsequent test results left them with more questions than answers. Tests both for the virus itself and for the antibodies the immune system produces to fight the infection are becoming more widely available, but they are not perfect. For Maree Johnson-Baruch, her husband, Jason Baruch, and their two teenage daughters, their experience ran the gamut. They all became sick around the same time with the same symptoms.

The federal government has received plenty of well-deserved flack for slow-rolling the national launch of diagnostic tests for Covid-19. First came the flawed swab-based tests from the Centers for Disease Control and Prevention, followed by a chaotic, lost month of regulatory tango that prevented independent tests from getting scaled and out the door. So when interest arose in a different kind of testing--antibody blood tests, which are used to find evidence of past infection, not a current diagnosis--the US Food and Drug Administration was under pressure to hurry things along. In mid-March, the agency loosened its rules, declaring via an update to its emergency use guidance that antibody tests could be sold without seeking the agency's approval, provided that manufacturers did their own validation. Now FDA officials are walking back that decision.

As the new coronavirus burns its way across the world, scientists are rushing to find ways to identify those who have been infected -- including those who have recovered from COVID-19. Those people, the thinking goes, may be immune to the deadly virus and could theoretically help restart the economy without fear of reinfection. One key piece of this puzzle is rolling out what are known as serological tests that look for specific antibodies in a person's blood. So far, they have been used to estimate how much of the population has been exposed in different areas, such as New York City and Los Angeles. But what are these tests, and can they really help to identify who is immune to SARS-CoV-2? From how they work to what they tell us, here's everything you need to know about coronavirus antibody testing.

MADRID – Some political leaders are hailing a potential breakthrough in the fight against COVID-19: simple pin-prick blood tests or nasal swabs that can determine within minutes if someone has, or previously had, the virus. The tests could reveal the true extent of the outbreak and help separate the healthy from the sick. But some scientists have challenged their accuracy. Hopes are hanging on two types of quick tests: antigen tests that use a nose or throat swab to look for the virus, and antibody tests that look in the blood for evidence someone had the virus and recovered. The tests are in short supply, and some of them are considered unreliable.