tetano
Editor, Senior Moderator
Viruses
. 2020 Jul 7;12(7):E735.
doi: 10.3390/v12070735.
Heat Inactivation of Different Types of SARS-CoV-2 Samples: What Protocols for Biosafety, Molecular Detection and Serological Diagnostics?
Boris Pastorino[SUP] 1 [/SUP], Franck Touret[SUP] 1 [/SUP], Magali Gilles[SUP] 1 [/SUP], Xavier de Lamballerie[SUP] 1 [/SUP], Remi N Charrel[SUP] 1 [/SUP]
Affiliations
Abstract
Standard precautions to minimize the risk of SARS-CoV-2 transmission implies that infected cell cultures and clinical specimens may undergo some sort of inactivation to reduce or abolish infectivity. We evaluated three heat inactivation protocols (56 ?C-30 min, 60 ?C-60 min and 92 ?C-15 min) on SARS-CoV-2 using (i) infected cell culture supernatant, (ii) virus-spiked human sera (iii) and nasopharyngeal samples according to the recommendations of the European norm NF EN 14476-A2. Regardless of the protocol and the type of samples, a 4 Log[SUB]10[/SUB] TCID50 reduction was observed. However, samples containing viral loads > 6 Log[SUB]10[/SUB] TCID[SUB]50[/SUB] were still infectious after 56 ?C-30 min and 60 ?C-60 min, although infectivity was < 10 TCID[SUB]50[/SUB]. The protocols 56 ?C-30 min and 60 ?C-60 min had little influence on the RNA copies detection, whereas 92 ?C-15 min drastically reduced the limit of detection, which suggests that this protocol should be avoided for inactivation ahead of molecular diagnostics. Lastly, 56 ?C-30 min treatment of serum specimens had a negligible influence on the results of IgG detection using a commercial ELISA test, whereas a drastic decrease in neutralizing titers was observed.
Keywords: COVID-19; ELISA; SARS-CoV-2; coronavirus; heat inactivation; neutralization; serology; virus neutralization test.
. 2020 Jul 7;12(7):E735.
doi: 10.3390/v12070735.
Heat Inactivation of Different Types of SARS-CoV-2 Samples: What Protocols for Biosafety, Molecular Detection and Serological Diagnostics?
Boris Pastorino[SUP] 1 [/SUP], Franck Touret[SUP] 1 [/SUP], Magali Gilles[SUP] 1 [/SUP], Xavier de Lamballerie[SUP] 1 [/SUP], Remi N Charrel[SUP] 1 [/SUP]
Affiliations
- PMID: 32646015
- DOI: 10.3390/v12070735
Abstract
Standard precautions to minimize the risk of SARS-CoV-2 transmission implies that infected cell cultures and clinical specimens may undergo some sort of inactivation to reduce or abolish infectivity. We evaluated three heat inactivation protocols (56 ?C-30 min, 60 ?C-60 min and 92 ?C-15 min) on SARS-CoV-2 using (i) infected cell culture supernatant, (ii) virus-spiked human sera (iii) and nasopharyngeal samples according to the recommendations of the European norm NF EN 14476-A2. Regardless of the protocol and the type of samples, a 4 Log[SUB]10[/SUB] TCID50 reduction was observed. However, samples containing viral loads > 6 Log[SUB]10[/SUB] TCID[SUB]50[/SUB] were still infectious after 56 ?C-30 min and 60 ?C-60 min, although infectivity was < 10 TCID[SUB]50[/SUB]. The protocols 56 ?C-30 min and 60 ?C-60 min had little influence on the RNA copies detection, whereas 92 ?C-15 min drastically reduced the limit of detection, which suggests that this protocol should be avoided for inactivation ahead of molecular diagnostics. Lastly, 56 ?C-30 min treatment of serum specimens had a negligible influence on the results of IgG detection using a commercial ELISA test, whereas a drastic decrease in neutralizing titers was observed.
Keywords: COVID-19; ELISA; SARS-CoV-2; coronavirus; heat inactivation; neutralization; serology; virus neutralization test.