CORONAVIRUS Temperatures / Survivability
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Anonymous
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Major takeaways from the science paper with link below: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3509683/ Three is WAY more information in this link.. goldmine of info. SARS-CoV lost its infectivity after 90 minutes at 56°C = 132.8F lost its infectivity after 60 minutes at 67 °C = 140 F lost its infectivity after 30 minutes at 75 °C = 167 F - 56 °C = 132.8F over 30 min reduced virus to undetectable - 60 °C = 140F over 30 min if associated with * proteins per below NO LOSS OF STABILITY: 4 °C, = 39.2F TIME LIMITED STABILITY: 20 °C = 68F to 2 hours 37 °C= 98.6F for at least 2 hours Suspension vs. Desiccation - SARS-CoV has been shown to survive after drying on different kinds of materials or diluted in water, revealing a decreased infectivity only after 72 to 96 hrs, depending on the conditions. - However, its infectivity is reduced more rapidly if it is deposited on porous surfaces such as cotton or paper Coronaviruses also well survive in suspension. At 37 °C, HCoV 229E and OC43 displayed survival rates of 80% and 100%, respectively, in phosphate buffered saline (PBS) over three days and of 30% and 55%, respectively, over six days. DRYING: The same study also showed that desiccation( the removal of moisture from something). has a more severe effect on coronaviruses. Indeed, in standard environmental conditions (21 °C and 50% to 70% of relative humidity), CoV 229E infectivity came down to 30% after three hrs of desiccation on various surfaces that can be found in hospital settings, such as aluminum, sterile sponges or surgical latex gloves. HCoV OC43 was more sensitive to desiccation, since its infectivity was below the detectable threshold after three hrs of drying Rabenau et al. made a comparative study on the stability of different viruses, i.e. SARS-CoV, HCoV 229E, type 1-herpes simplex virus (HSV-1) and the type 3-adenovirus, in suspension and after drying. In medium culture, with and without 10% FCS, the HCoV 229E progressively lost its infectivity over nine days, which is consistent with the previous study. The infectious titers of the three other viruses, including the SARS-CoV, were stable over nine days, with and without proteins. After drying on a plastic surface, the HCoV 229E and the HSV-1 lost their infectivity in 72 hrs, in the presence or absence of FCS. In contrast, the SARS-CoV retained its infectivity for as long as six days, with a further protecting effect of proteins. It took nine days in a dried state, for SARS-CoV to completely lose its infectivity. The adenovirus was the most stable virus assayed as it conserved its infectivity throughout the nine days of the experiment These studies firmly illustrated the potency of coronaviruses and especially the SARS-CoV, to be transmitted via other routes than respiratory droplets and the likely risk of contamination via surfaces and fomites. It should also be noticed that the residual infectivity of those enveloped viruses in different conditions can almost reach the one of non-enveloped viruses. This reappraises the environmental stability of these two types of viruses. A more recent study implicated water and sewage in the transmission of SARS-CoV, taking the MHV and the TGEV as surrogates for their experiments. At 25 °C, the time required for 99% reduction in water was 22 days for TGEV and 17 days for MHV, and, in sewage, it took nine days for TGEV and seven days for MHV. After four weeks in almost the same conditions but at 4 °C, there was less than <1 log10 infectivity decrease for both viruses. The authors concluded that in case of SARS-CoV re-emergence water contaminated with fecal waste should be considered as a potential vehicle of transmission |
Anonymous
| bmp. |
Anonymous
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For those who wonder how long it can live on clothing.. based on the above paper you can extrapolate:
So it should be around or less then three to four days in a normal tem and humidity conditoins. - SARS-CoV has been shown to survive after drying on different kinds of materials or diluted in water, revealing a decreased infectivity only after 72 to 96 hrs, depending on the conditions. - However, its infectivity is reduced more rapidly if it is deposited on porous surfaces such as cotton or paper |
Anonymous
| Thank you. Great post. |
Anonymous
Pleasure to help. |
Anonymous
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‘ A more recent study implicated water and sewage in the transmission of SARS-CoV, taking the MHV and the TGEV as surrogates for their experiments. At 25 °C, the time required for 99% reduction in water was 22 days for TGEV and 17 days for MHV, and, in sewage, it took nine days for TGEV and seven days for MHV. After four weeks in almost the same conditions but at 4 °C, there was less than <1 log10 infectivity decrease for both viruses. The authors concluded that in case of SARS-CoV re-emergence water contaminated with fecal waste should be considered as a potential vehicle of transmission ’
Can someone translate this for me as it relates to DC tap water? Isn’t municipal DC tap water cleaned, and decontaminated sewer water? If so ( and I could be completely wrong) are we looking at possible COVID contamination issues? |
Anonymous
I am not an expert but first question would be - is your water contaminated with COVID? I would think not. Second thing - I would assume that the city water is heavily decontaminated by means of chemicals. Third - if you have any concerns. Boil your water for the prescribed time per the research above.. as stated in the quote below.. if it provides temperature of 75C exposure for 30 minutes to kill the virus completely and the 75C is the closest I could find to the boiling point of 100C. Then in theory the higher temps you go the shorter time it takes to kill the virus. So if it is 30 minutes for 75C then it should be less then 30 for 100C. How much less I don't know because the study does not specify. But if you boil it for the given 30 minutes it would be completely safe. SARS-CoV lost its infectivity after 90 minutes at 56°C = 132.8F lost its infectivity after 60 minutes at 67 °C = 140 F lost its infectivity after 30 minutes at 75 °C = 167 F Most people if not everyone in most countries if not every of them would never drink raw decontaminated municipal water if you paid them however beautifully it would be chemicized. People boil water to boil out all the things theyc can boil out of it. That covers your tap water for drinking. Now could be the tap water contaminated and what happen if you take a shower or bath in such water that is another story beyond my ability to extrapolate from this in such context comfortably. If you use your imagination you could arrive to some conclusion. The question is what is actual exposure of the water to the fecal matter, what is the effectiveness of the chemicals and how long is it being in the presence of them. At the end of the day it might be completely safe and free of viruses but this is a question for your water system company. Just call and ask if their system catches and or kill all the virus. There is a lot of hope and some comfort in the thought that since you are taking shower or bath with tons of suds, the virus would need to capitulate aka surrender to the slippery slope of your soaped bottom and just weeeeee slide off your body because however many little hands it has and tries to grab to you as much as possible, the good old soap makes it impossible to hold and I will slide off of you just as the kid goes fast on a snowy slope. |
Anonymous
Just call your city water company. This is a good question and we all would like to hear from you once you get some info. Maybe we can all learn something here. |
Anonymous
Washington Water website re COVID: Frequently Asked Questions How will COVID-19 impact my water quality? Tap water is safe to drink. There is no evidence COVID-19, the disease caused by the coronavirus can survive in treated drinking water. The same disinfectants, like chlorine, that make the water safe to drink, are effective against COVID-19. DC’s drinking water has two stages of disinfection during the water treatment process before it is distributed to the city. The first stage is free chlorine and the second is chloramine, both very effective at killing viruses. Additionally, residual disinfection levels throughout our pipe distribution system remain at effective levels to keep the water clean and safe. Click here for more information. Wow! Makes you wander what we are drinking.. looks like we almost could use the pure tap water to wipe the groceries and not even blink. It should take care of the surface virus?  Just kidding.
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Anonymous
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That part is interesting:
After drying on a plastic surface, the HCoV 229E and the HSV-1 lost their infectivity in 72 hrs, in the presence or absence of FCS. |