P eople who alr eady had CO VID- 19 should still get v accinated, scientists ur ge Va cci nes bo ost na t ural i mmune r esponses and have an amazi ng tr a ck r ecord of pr event i ng serious il lness and de a t h.

As  the U  .S.  grap  ples w  ith   its   troub  led v  accin  e rol  lout,  an a  larm  ing inc  reas  e in c  orona  viru  s ca  ses  acr  oss  the n  atio  n has  resurfac  ed a   long- simmering qu  esti  on:  Do pe  ople w  ho’v  e alr  eady  had  COVI  D-19   need to be vacci nated? Nat ural immu nity is a powe rful f orce a gai nst c ertai n dis eas es, such as chi ckenp ox an d mea sles . Su rviv ing a nat ural m eas les i nfecti on ca n yie ld im munit y tha t is com parab le—or in s ome case s, superi or—to va ccina tion , sa ys Rut  h Karron , a pedi atri cian and p rofes sor at th e Johns Ho pkins Blo ombe rg Sc hool of Public Heal th in Bal timo re. But firs t, of cour se, the pa tien t has to surv ive. It’ s al so no t yet crys tal clear wheth er im muni ty fr om co ntra cting COV ID-19 is as p owerfu l as the p rotec tion of a vacc ine. What is ev iden t is tha t the ava ilabl e va ccines mou nt cru cial defens es a gai nst s evere diseas e and deat h—ev en aga ins t mor e con tagi ous v ari ants such as D elta. And rese arch show s th at ev en a singl e dos e of an m RNA v acci ne fro m Mod erna or Pfizer-BioNTech boos ts immu nity for pe ople w ho’v e ha d the dis ease . “I would recom mend to a nyone who hasn ’t be en va ccina ted to go ahea d and get vacci nate d as soo n as they can, ” sa ys All  iso  n Grea  ney, a res earch er at Fred Hutc hins on Ca ncer Resea rch Center in Se attle , adding that the v acci nes “prot ect us so well a gain st a very dang erous vi rus. ” More robust antibodies At Fred Hutch inso n, gr adua te st udent Grea ney le d a r esea rch te am t hat publish  ed a   recent  stud  y su  ggest  ing   vac  cines  giv  e peo  ple an  impo  rtant edg  e ov  er nat  ural   immu  nity.  The  team  look  ed at the  anti  bodi  es of peo  ple wh  o had  reco  vered  from  COV  ID-19  , as  well   as p  eople   who’d rece  ived  two   dose  s of  the M  odern  a mRNA va  ccine  as   part of th  e com pany’ s ph ase one tr ial. The rese arche rs fo und t hat b oth group s gen erate d ant ibod ies that tar geted the recept or bi nding dom ain, or R BD. As it s na me sugges ts, thi s pa rt of the SARS -COV-2 vi rus helps it s tick to a nd ul tima tely gain entry to huma n cell s, c ausi ng an infec tion. If a ntibo dies att ach to th e RB D ins tead, they can neutra lize the virus .

The rese arch revea led t hat the a ntibo dies of r ecov ered C OVID- 19 patients stu ck m ostl y to an ar ea of the RBD t hat i nclud es th e si te E484— a   porti  on of  the   virus  tha  t ha  s mu  tated  in s  ome   vari  ants  . By co ntra st, the ant ibod ies in va ccina ted people bound mor e bro adly acro ss t he d omai n, all owing them to targe t are as t hat a re s till prese nt in som e var iants , includin g Bet a, Gamma, an d Delt a. SARS-CO V-2 takes “gr eat p ains” to mask it s RB D, using m olecu lar tri cker y to make the r egio n har d for anti bodi es to fin d, b ecaus e it’ s th e mo st vulnera ble pa rt of the viru s, s ays Amy Hart man, an a ssoc iate profess or of infec tiou s di seas e and mic robio logy at t he Univer sity of Pittsburgh. But mRNA vacc ines are built to ta rget the R BD an d se nd pot ent a ntibo dies to i t. A nd th e new f indi ngs sugge st th at i mmuni ty fro m mRNA va ccine s “s eems to be mor e robust t han natura l im munit y in many case s,” Grea ney s ays. Researchers   alrea  dy k  new th  at C  OVID-  19 va  ccine  s “reli  ably  indu  ce ant  ibod  y lev  els” th  at ar  e as  high  or   even h  ighe  r tha  n tho  se of peop  le who ha  ve rec  over  ed fro  m se  vere   cases  of   coron  avir  us,   says  Karron,   who w as not part of t he new stud y. T his Fred Hutch inso n tea m’s work sho ws th at va ccina tion “giv es us bo th mo re an tibo dies and bette r ant ibod ies, ” sh e adds. “It’s a q uanti ty and qua lity issue.” So , wh y the debate ? Oth er re searc h, h oweve r, ma kes the c ase t hat natur al im muni ty to COVID-19 mig ht be robu st. A team of resea rcher s eva luat ed 254 peo ple up to eig ht m onths aft er th ey ha d rec overe d fro m CO VID-19 and found they ha d “du rable , bro ad-b ased imm une re spons es. ” Tha t was tru e even for thos e wh o had suf fered only mild dis ease , acc ordi ng to thei r stu dy, whi ch wa s pub  lis  hed l  ast   month  . Sci enti sts know that othe r dis eas es ca n conf er la stin g nat ural immu nity. Aft er a singl e chi ckenpo x inf ectio n, a perso n wil l lik ely have life- long im munit y ag ains t the itchy and som etim es-d eadly dis ease . To get t he sa  me lo  ng-la  stin  g im  munit  y fro  m a v  acci  ne, t  hat p  erso  n woul  d n  eed t  wo sh  ots,  giv  en yea  rs a  part  .

But  befo  re chi  ckenp  ox va  ccine  s wer  e dev  eloped  , ab  out  10  ,00  0 U.  S. chi  ldren  and   adult  s wer  e hospita  liz  ed eac  h yea  r wi  th t  he di  seas  e, wi  th sy  mptom  s i  ncludi  ng lu  ng and  blo  od i  nfecti  ons. For SAR S-CoV-2, “I ca n’t m ake the ca se t hat [vac cinat ion or nat ural im munit y] is nece ssa rily bette r tha n the othe r bas ed on any knowledge tha  t I a  ctual  ly po  sses  s a  bout   this  part  icula  r vi  rus,  ” sa  ys   Cha  rlot  te Cunn  ingha  m-Ru  ndles  ,  the David  S.   Gott  esma  n Pro  fess  or of Imm unolo gy at the Mount Sin ai S choo l of Medici ne. But  she   hast  ens to add: “I don't th  ink   anyo  ne’s   collec  ted e  nough  data  to sa y tha t so mebo dy wh o’s had this vi rus on thei r ow n doe s not need to get vacc inat ed.” Karron a lso notes tha t one of th e “g reat u nsolved m yst eries” of SARS - CoV-2 is why so me peo ple h ave a sym ptoma tic or mi ld d isea se, while oth ers are a fflic ted wi th s evere infec tion s. In the s ame vein , sci entis ts are sti ll st ruggl ing to und erst and w hen an d why cert ain p eople will dev elop stro nger i mmun e response s th an ot hers . For ins tance , sa ys H artm an, s tudi es h ave s hown that som e rec overe d pat  ients  can   mount  effec  tive   defens  es a  gain  st C  OVID-  19, but an  tibo  dy lev  els d  roppe  d rap  idly  in o  thers  who  were   infect  ed. S  cient  ist  s ar  e sti  ll gat  heri  ng da  ta a  nd ra  cing   to an  swer   this  key  quest  ion   and o  thers  , such as  how   long   immu  nity   last  s fro  m va  ccine  s or  from  natu  ral i  nfecti  on. With va ccina tion , mo st pe ople a re al l but guar anteed to have a st rong immune r espon se—a nd th at i nclude s peo ple wh o’ve alre ady c ontra cted COV ID-19. Mul tiple stud ies have sho wn tha t ev en a singl e dos e of an mRNA va ccine b  oost  s an  tibo  dy le  vels  in recov ered pati ents, giv ing t hem the  sam  e peak  respons  e t hat two s hots aff ord p eople who h aven’ t ha d the dis ease . Today, more than 97 percent of pe  ople   hospi  tali  zed   for C OVID- 19 in the U. S. a re unv acci nated . And whil e a s mall percen tage of v accin ated peo ple ha ve be en inf ected with the v irus , th eir c ases are overwhelm ingly mi ld. On Mon day, U.S . Se nator Lind sey Grah am, who w as v acci nated in Dece mber, anno unced that he h  ad t  ested  positiv  e for  COV  ID-19 aft er expe rienci ng o nly m ild s ympt oms . “I am v ery gl ad I was vacci nate d,” t he So uth C aroli na Republi can s aid in a sta tement , “b ecaus e wit hout va ccina tion , I am cert ain I woul d not feel as we ll as I do now. My sy mptom s wo uld be far wors e.”

The CDC r eport s 0.0018 p  ercent  of C OVID -19 d eaths fro m Dece mber 14, 2020, to Ju ly 19 were amon g the vacc inat ed. A nd th at, e xperts sa y, is pro of th e va ccines work. “For ma ny pa thog ens, we’re a bi t hum ble,” Karr on s ays. For som e diseas es, such as HIV or mal aria, “y ou do n’t w ant to get infe cted at al l,” sh e say s. “But for a lot of pa thoge ns—a nd especia lly fo r th ings lik e respira tory patho gens , li ke CO VID-1 9—our goa ls ar e a l ittl e mor e mo dest . Our goal is reall y to preve nt se vere d isea se a nd d eath. ”

PHOTOGRAPH BY MARIO T  AMA, GETTY

Regi ster ed nur se Da rr yl Hana admi ni ster s a dose of the P fizer COVID-19 va cci ne to Concepc ion Wi tr on at Pr ovi dence Wilmi ngton Wel lness and Activi ty Center in Cal i for nia. For peopl e who’ve a l ready been sick, even a si  ngl  e dose of    an mRNA va  cc  i  ne    l  ike    P  fizer’  s    can bo ost i m... Re ad M o re

B Y JILL IAN KR A M E R PUBLISHED AUGUST 4, 202 1 6 MIN REA D

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