<figure>
 <img src="https://media.eaglewebservices.com/public/2020/10/1602251360190.png" alt=" Photo illustration by Celia Llopis-Jepsen / Kansas News Service" />
 <figcaption> Photo illustration by Celia Llopis-Jepsen / Kansas News Service</figcaption>
 </figure>By CELIA LLOPIS-JEPSEN <a href="https://www.kcur.org/news/2020-10-08/clues-from-the-blood-of-kansans-suggest-the-coronavirus-pandemic-could-stick-around-for-a-long-time">Kansas News Service</a>Perhaps two in every 50 Kansans have <a href="https://www.livescience.com/antibodies.html" target="_blank">antibodies</a> swimming in their bloodstream that show they’ve had COVID-19.That relatively low number — based on the assumption that <a href="https://www.redcross.org/give-blood.html" target="_blank">blood donors</a>
 reflect the broader population — suggests a gloomy reality. Kansas is 
still in the early days of this pandemic and it's looking at a future 
likely to bring many more cases than it has so far seen.“Absolutely,”
 said Roger Shapiro, an immunologist at Harvard University’s School of 
Public Health. “When you look at these figures, you realize how far we 
are from herd immunity.”The overwhelming number of Kansans, perhaps more than 95%, haven’t yet experienced the virus that has killed more than <a href="https://coronavirus.jhu.edu/data/mortality" target="_blank">200,000 Americans</a>.So
 medical pros say the only thing to do is sit tight, keep your masks on 
and stay away from other people, until we have a vaccine.That, and get a flu shot.“This
 is not the time to play a guessing game of, ‘Do I have the flu or do I 
have COVID?’” said Gigi Gronvall, an immunologist at Johns Hopkins’ 
Center for Health Security.Many people still can’t get fast 
coronavirus tests that would let them isolate in time to stop the 
disease from spreading further, and hospitals remain at risk of getting 
overwhelmed by coronavirus and flu cases this fall.<h2>Clues in the blood</h2>The
 human body produces antibodies when exposed to a disease, to fend it 
off. And those microscopic defenders can stick around after recovery.So the American Red Cross screens blood donations for antibodies against <a href="https://www.who.int/emergencies/diseases/novel-coronavirus-2019/technical-guidance/naming-the-coronavirus-disease-(covid-2019)-and-the-virus-that-causes-it" target="_blank">SARS-CoV-2</a>, the virus behind COVID-19. It then sends <a href="https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=160&amp;ContentID=37" target="_blank">plasma</a>
 with the specialized proteins to hospitals treating coronavirus 
patients, and it reports how often it detects the antibodies to state 
health agencies trying to piece together the bigger picture.Nationally, the <a href="https://www.redcross.org/give-blood.html" target="_blank">Red Cross</a> has tested about 1.2 million blood donations for the antibodies.From
 mid-June to mid-September, it found them in about 2% of donations 
nationally. The same was true for Kansas donors. It’s not known how well
 that statistic might reflect the broader population.Weekly 
tallies suggest the number of people carrying the antibodies has ticked 
upward in Kansas, as elsewhere. In recent weeks, the Red Cross reported 
antibodies in 4% to 5% of Kansas donations.Could someone with 
antibodies catch the virus again a year from now and get seriously sick?
 How about two years from now? Or could they catch it, not show any 
symptoms, and spread the virus anyway? Scientists can’t yet say.“This
 is not a get-out-of-jail-free card,” Gronvall said. If a test shows you
 have antibodies, she said, you should still wear a mask and follow 
social distancing rules.Recent reports of a few patients catching the novel coronavirus <a href="https://www.statnews.com/2020/08/28/covid-19-reinfection-implications/" target="_blank">more than once</a>
 in a relatively short time may not signal what to expect for most 
people, but leave open the possibility that one infection doesn’t 
protect you against another.<h2>Greater risk</h2>The Red Cross reported in <a href="https://jamanetwork.com/journals/jama/fullarticle/2770771" target="_blank">a medical journal</a>
 last month that blood donations from people of color test positive for 
the antibodies at a higher rate than blood from white donors.That matches <a href="https://www.mayoclinic.org/diseases-conditions/coronavirus/expert-answers/coronavirus-infection-by-race/faq-20488802" target="_blank">other research</a>
 that shows communities of color bearing the brunt of the pandemic. It 
likely reflects broader social and economic disparities, such as lower 
incomes and a greater likelihood of working high-risk jobs that involve 
in-person contact with many customers or colleagues in a single day.The virus spread fast in crowded Kansas <a href="https://www.hppr.org/post/emails-show-kansas-agencies-helped-keep-meatpacking-plants-open-despite-concerns-about" target="_blank">meatpacking plants</a>, for example, that rely heavily on the labor of people of color in southwest Kansas.<h2>The need for a vaccine</h2>Some
 studies and modeling point to higher antibody rates nationally and 
globally than the Red Cross has seen among blood donors, but still don’t
 offer good news.“The (World Health Organization) just came out with an estimate that maybe <a href="https://abcnews.go.com/Health/wireStory/10-worlds-people-infected-virus-73427817" target="_blank">up to 10%</a>
 of the world has been infected,” Shapiro said. “But even at that 
number, we’re still so far from achieving herd immunity. … We really 
need to create immunity with a vaccine.”Vaccines <a href="https://www.cdc.gov/vaccines/hcp/conversations/downloads/vacsafe-understand-color-office.pdf" target="_blank">mimic natural infections</a>. They kick a person’s immune system into gear so that it churns out antibodies and stores viral information in <a href="https://askabiologist.asu.edu/memory-b-cell" target="_blank">memory cells</a>
 that could defend us even after those antibodies fade. (Researchers 
have found SARS-CoV-2 antibodies triggered by natural infection two or 
even three months after infection, and say it varies from person to 
person.)Ongoing coronavirus vaccine trials aim to check how 
protective these immune responses will prove long-term, and whether 
people will need booster shots over time to keep their defenses up.Part
 of the benefit from vaccines will ultimately come from the sheer number
 of people who would gain some level of protection at once.“As we
 get to high enough vaccine levels, the herd immunity will actually just
 lower the amount of virus that’s circulating,” Shapiro said. “There 
will be just less virus around. This is our hope.”<h2>Should you get an antibody test?</h2>The Red Cross’ free antibody tests serve three functions.They
 gather the information that helps public health experts studying the 
virus’ spread, and they allow the Red Cross to flag plasma with 
antibodies for hospitals.Scientists <a href="https://thehill.com/policy/healthcare/513405-science-inconclusive-on-use-of-convalescent-plasma-in-covid-19-patients" target="_blank">still can’t say</a> whether the donated plasma works for treating COVID-19. A separate, <a href="https://www.sciencemag.org/news/2020/09/provocative-results-boost-hopes-antibody-treatment-covid-19" target="_blank">lab-based approach</a>, may prove more effective.But either way, donations remain as critical as ever to the nation’s blood supply.And that’s a third reason for offering antibody tests. They attract people to <a href="https://www.redcross.org/give-blood.html" target="_blank">keep donating</a> amid the pandemic.The
 Red Cross uses respected tests, and when a blood sample proves positive
 for antibodies, it double-checks with a second, high-quality process.For
 people who had respiratory symptoms in recent months — but couldn’t get
 checked for COVID-19 because of the nationwide shortage of <a href="https://www.cdc.gov/coronavirus/2019-ncov/hcp/testing-overview.html" target="_blank">viral tests</a> — that may satisfy their curiosity.And
 that could help keep donations flowing as the pandemic hampers 
traditional blood drives, such as a major annual effort that would have 
attracted thousands of donors next week.“The biggest blood
 drive the Red Cross does across the country is at the University of 
Missouri in Columbia,” said Joe Zydlo, a regional communications manager
 in St. Louis. “And that has been canceled.”Meanwhile, Gronvall 
advises against buying an antibody test somewhere. After all, the 
information won’t help you medically, she said, and many products are 
unreliable anyway.“There’s just been so many bad tests out there,” she said. “Right now I would not spend money on it.”Celia Llopis-Jepsen reports on consumer health and education for the Kansas News Service. You can follow her on Twitter <a href="https://twitter.com/Celia_LJ" target="_blank">@celia_LJ</a> or email her at celia@kcur.org.

Antibody tests show 'we’re still so far from achieving herd immunity'