<300 mmhg. severe symptoms causing hospitalization or death, are those requiring treatment at hospitals or results in deaths: dyspnea, hypoxia, persistent chest pain, anorexia, confusion, fever above 38 °c (100 °f), respiratory failure, kidney failure, multiorgan dysfunction, sepsis, shock. with twelve weeks or more between doses. for an interval of less than six weeks, the trial found an efficacy 55% (33–70%). a confidence interval was not provided, so it is not possible to know the accuracy of this measurement. with a four-week interval between doses. efficacy is "at preventing symptomatic covid-19". covid-19 symptoms observed in the pfizer–biontech vaccine trials, were only counted as such for vaccinated individuals if they began more than seven days after their second dose, and required presence of a positive rt-pcr test result. mild/moderate cases required at least one of the following symptoms and a positive test during, or within 4 days before or after, the symptomatic period: fever; new or increased cough; new or increased shortness of breath; chills; new or increased muscle pain; new loss of taste or smell; sore throat; diarrhoea; or vomiting. severe cases additionally required at least one of the following symptoms: clinical signs at rest indicative of severe systemic illness (rr ≥30 breaths per minute, hr ≥125 beats per minute, spo2 ≤93% on room air at sea level, or pao2/fio2<300mm hg); respiratory failure (defined as needing high-flow oxygen, non-invasive ventilation, mechanical ventilation, or ecmo); evidence of shock (sbp <90 mm hg, dbp <60 mm hg, or requiring vasopressors); significant acute renal, hepatic, or neurologic dysfunction; admission to an icu; death. this measurement is not accurate enough to support the high efficacy because the lower limit of the 95% confidence interval is lower than the minimum of 30%. moderate cases. efficacy reported 28 days post-vaccination for the janssen single shot vaccine. a lower efficacy was found for the vaccinated individuals 14 days post-vaccination. no hospitalizations or deaths were detected 28 days post-vaccination for 19,630 vaccinated individuals in the trials, compared with 16 hospitalizations reported in the placebo group of 19,691 individuals (incidence rate 5.2 per 1000 person-years) and seven covid-19 related deaths for the same placebo group. mild/moderate covid-19 symptoms observed in the moderna vaccine trials, were only counted as such for vaccinated individuals if they began more than 14 days after their second dose, and required presence of a positive rt-pcr test result along with at least two systemic symptoms (fever above 38ºc, chills, myalgia, headache, sore throat, new olfactory and taste disorder) or just one respiratory symptom (cough, shortness of breath or difficulty breathing, or clinical or radiographical evidence of pneumonia). severe covid-19 symptoms observed in the moderna vaccine trials, were defined as symptoms having met the criteria for mild/moderate symptoms plus any of the following observations: clinical signs indicative of severe systemic illness, respiratory rate ≥30 per minute, heart rate ≥125 beats per minute, spo2 ≤93% on room air at sea level or pao2/fio2 <300 mm hg; or respiratory failure or ards, (defined as needing high-flow oxygen, non-invasive or mechanical ventilation, or ecmo), evidence of shock (systolic blood pressure <90 mmhg, diastolic bp <60 mmhg or requiring vasopressors); or significant acute renal, hepatic, or neurologic dysfunction; or admission to an intensive care unit or death. no severe cases were detected for vaccinated individuals in the trials, compared with thirty in the placebo group (incidence rate 9.1 per 1000 person-years). these phase iii data have not been published or peer reviewed. no cases detected in trial. effectiveness