Ak niekto v súčasnosti hovorí, že očkovanie proti Covidu nie je účinné, respektíve že neexistujú dostatočné dôkazy o jeho účinnosti, tak si danú problematiku vôbec nenaštudoval.
3. fáza klinického skúšania Pfizer/BioNTech/BNT162b2 mRNA vakcíny (18) porovnávala 21720 osôb, ktorým bola aplikovaná vakcína, a 21728 osôb, ktorým bola aplikovaná injekcia s fyziologickým roztokom (placebo). 2 dávky vakcíny zabezpečili 95% ochranu proti symptomatickej infekcii (infekcia s príznakmi). Pozorované nežiaduce účinky boli vlastne znaky imunitnej rekacie podobne ako u iných vakcín (vyčerpanosť, bolesť hlavy, bolesť svalov a kĺbov, zimnica, …).
10 Nasledujúcich štúdií v tabuľke porovnávalo výskyt Covid infekcií, vrátane tých asymptomatických, u očkovaných a neočkovaných. Potvrdzujú vysokú účinnosť po očkovaní 2 dávkami Pfizer/BioNTech vakcíny.
| štúdia | počet osôb | účinnosť 2 dávok proti infekcii | poznámka |
| Pawlowski (1) | 31069 očkovaných 31069 neočkovaných | 89% | |
| Swift (2) | 49220 | 97% | |
| Thompson (3) | 3975 | 91% | |
| Björk (4) | 805741 | 86% | |
| Lumley (5) | 13109 | 90% | |
| Hall (6) | 23324 | 85% | |
| Shah (7) | 144525 | 92% | zníženie šírenia nákazy o 60% |
| Heymann (8) | 6286 | 89% | |
| Dagan (9) | 596618 očkovaných 596618 neočkovaných | 92% | 90% účinnosť proti asymptom. infekcii |
| Moustsen-Helms (10) | 39040 seniori 331039 zdravotní pracovníci | 64% 90% |
Výsledky ďalších 5 štúdií jasne ukazujú účinnosť Pfizer/BioNTech vakcíny proti asymptomatickej (bezpríznakovej) infekcii.
| štúdia | počet osôb | účinnosť 2 dávok proti asymptom. infekcii | poznámka |
| Tang (11) | 2776 očkovaných 2165 neočkovaných | 90% | |
| Haas (12) | 6538911 | 92% | |
| Angel (13) | 5372 očkovaných 696 neočkovaných | 86% | |
| Regev-Yochay (14) | 9650 | 65% | zníženie šírenia nákazy |
| Tande (15) | 39156 | 80% |
Pár poznámok na záver:
– očkovanie znižuje výskyt Covidu nielen u očkovaných, ale aj u neočkovaných prostredníctvom kolektívnej imunity (16, 17, 19, 24, 25, 26)
– žiadna vakcína nie je na 100% účinná podobne ako napr. ani bezpečnostné pásy v aute nie sú na 100% účinné, preto je pochopiteľné, že malé percento očkovaných stále môže ochorieť (s ľahším priebehom ako u neočkovaných), a je taktiež pochopiteľné, že to nijako nevyvracia výsledky vyššie uvedených štúdií
– ak sa očkovaní nakazia, majú menšiu vírovú nálož, a tak aj významne nižšiu pravdepodobnosť šírenia infekcie v porovnaní s neočkovanými (20, 21, 22, 23, 3, 14)
Článok bol naposledy aktualizovaný 24.7.2021.
Zdroje:
1.Pawlowski C LP, Puranik A, et. al. FDA-authorized COVID-19 vaccines are effective per real-world evidence synthesized across a multi-state health system. medRxiv. 2021; https://www.medrxiv.org/content/10.1101/2021.02.15.21251623v1.full.pdf
2. Swift MD, Breeher LE, Tande AJ, Tommaso CP, Hainy CM, Chu H, et al. Effectiveness of mRNA COVID-19 vaccines against SARS-CoV-2 infection in a cohort of healthcare personnel. Clin Infect Dis. 2021.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8135611/pdf/ciab361.pdf
3. Thompson MG et al. Prevention and Attenuation of Covid-19 with the BNT162b2 and mRNA-1273 Vaccines. NEJM. 2021. https://www.nejm.org/doi/full/10.1056/NEJMoa2107058
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5. Lumley SF RG, Costantindes B., et al. An observational cohort study on the incidence of SARS-CoV-2 infection and B.1.1.7 variant infection in healthcare workers by antibody and vaccination status medRxiv. 2021; https://www.medrxiv.org/content/10.1101/2021.03.09.21253218v1.full.pdf
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