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The combined high pressure and heat resistances of spores of five proteolytic Clostridium botulinum strains and of the nonpathogenic surrogate strain Clostridium sporogenes PA3679 were compared with their heat-only resistances on the basis of equivalent accumulated thermal lethality, expressed as equivalent minutes at a reference temperature of 105°C (F 105°C ). Comparisons were made with three model (i.e., diluted) products, namely, 30% (wt/wt) Bolognese sauce, 50% (wt/wt) cream sauce, and rice water agar. Pressure was determined to act synergistically with heat during high-pressure thermal (HPT) processing for C. botulinum FRRB 2802 (NCTC 7273) and C. botulinum FRRB 2804 (NCTC 3805 and 62A) in the Bolognese and cream sauces and for C. botulinum FRRB 2807 (213B) in the Bolognese sauce only. No synergy was observed for C. botulinum FRRB 2803 (NCTC 2916) or FRRB 2806 (62A) or C. sporogenes FRRB 2790 (NCTC 8594 and PA3679) in any of the model products. No significant protective effect of pressure against spore inactivation was determined for any Clostridium strain in any product. Because synergy was not consistently observed among strains of C. botulinum or among products, the prediction of inactivation of C. botulinum spores by HPT sterilization (HPTS) for the present must assume a complete lack of synergy. Therefore, any HPTS process for low-acid shelf-stable foods must be at least thermally equivalent to an F 0 process of 2.8 min, in line with current good manufacturing practices. The results of this study suggest that the use of C. sporogenes PA3679 as a surrogate organism may risk overestimating inactivation of C. botulinum by HPT processing.Low-acid shelf-stable products that are microbiologically safe and stable are not obtainable by high-pressure processing (HPP) at near-ambient temperatures, as bacterial spores can survive pressures above 1,500 MPa (3,6,16,35), which far exceed the pressure capabilities of current commercial HPP equipment. Extensive inactivation of bacterial spores by high pressure is likely only to be realized in combination with initial process temperatures that exceed 60°C (16,20,23,24,31,37,39; C. M. Roberts and D. G. Hoover, presented at the Institute of Food Technologists 1996 annual meeting). Of particular interest (and concern) for low-acid shelf-stable foods is the ability of a combined high pressure and heat process to synergistically inactivate spores of the major bacterial spore-forming pathogens of concern, which are proteolytic strains of the neurotoxigenic species Clostridium botulinum.The combined high pressure and heat resistances of spores of a number of proteolytic C. botulinum strains in a number of different matrices have been investigated. Proteolytic C. botulinum type A BS-A and 62A spores were inactivated by 2 and 3 log 10 , respectively, in phosphate buffer (0.067 M, pH 7.0) after 20 min at 827 MPa at 75°C and by 3.2 log 10 and 2.7 log 10 , respectively, in a crabmeat blend (pH 7.2 to 7.4) after 15 min (29). For mashed carrot, a 12-min process at 600 MPa and 80°C ...

Long COVID is the term coined by patients to describe the longterm consequences of COVID-19, the 2019 pandemic disease caused by the new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). 1 We define long COVID as the presence of signs and symptoms that develop during or following an infection consistent with COVID-19 and continue for 4 weeks or longer. 10 The term includes "postacute COVID-19" (4-12 weeks) and "post-COVID syndrome" (12 weeks or longer). 10 Early reports of long-term sequelae focused on hospitalized patients, which drove rehabilitation teams to apply exercise-based protocols for patients who were deconditioned during intensive-care hospital stays. 11Even mild cases of COVID-19 in the community may lead to long COVID. 3 As many countries confront surging COVID-19 case numbers, new evidence describes the prevalence of persistent symptoms of COVID-19 infection after 6 months. 3,6 At least half of patients living with long COVID will continue to