Can I Contract Covid-19 From Objects?
A story of why I now own a pair of cotton outdoor pants.
Since the outbreak of COVID-19, I find myself unsure of if and what items should be disinfected. Though some of the sources online claim that food and objects are not of concern, the second wave of COVID-19 in China due to contaminated salmon gives me doubts about such statements¹⁰.
I have further reduced the frequency of my in-person shopping trips and limited the type of purchases since. Even so, while putting away my groceries or unpacking the delivered goods, I am wondering if I am doing enough to clean up the product and to protect my family from the potential infectious SARS-CoV-2 virus that we can still be in contact with. Therefore, I turned to published literature to help me address some of my questions, and I would like to share my learnings with you.
Is it possible to get infected via inanimate objects?
In short, the unfortunate answer is yes.
When SARS-CoV-2 is known to primarily spread via aerosols and respiratory droplets, fomites (inanimate objects) can contribute to the transmission of the virus. Serval studies have researched the stability of SARs-CoV-2 on inanimate surfaces ¹-¹⁰. Their results indicating that it is possible to contract COVID-19 via inanimate surfaces/material since the virus can survive for a prolonged period on these surfaces. However, the SARs-CoV-2 virus has different stability on different materials, suggesting different materials can be associated with different virus’ survival times.
How long can the virus survive on different surfaces?
When the exact time the virus remains viable (alive, able to infect) on various surfaces vary due to different factors, such as virus’ concentration, environmental temperature, relative humidity, environment’s PH level, and the specific strains of the virus, it can be between a few hours to a week ¹-¹⁰, or even to 28 days ².
In general, the virus becomes non-infectious faster on absorbable, porous materials, such as cotton, tissue paper, and printing paper than non-porous materials, such as plastic, PVC, glass, and stainless steel material. Copper, however, has been repeatedly reported as an exception among other non-porous materials. It can reach the level of non-detectable level of virus (around a few hours depending on temperature) faster than even cotton or paper ¹-⁵.
Higher temperature, higher humidity, and strong acidic (PH < 3), like rice vinaigrette, or strong alkaline(PH >12) are found to be advantages for decreasing the virus’ survival time ⁶-⁷.
What about food items?
Failed experiments attempting to infect poultry with SARS-CoV suggest that it is unlikely for the consumer to be exposed to foods from infected avian hosts8. Given that SARS-CoV-2 is a mammalian strain, it was also believed that similar to avian hosts, fish and shellfish are unlikely to be live hosts for the virus as well ⁸.
However, poor hygiene during food processing and preparation can result in contaminated food and water, and lead to COVID-19 infection ⁸-⁹. Additionally, refrigeration (~4C) does not reduce the infectiousness of the virus, and the virus can survive on inoculated meat and seafood for 3 weeks ⁹.
Coronavirus on lettuce in common refrigerator temperature (~4C) can survive for 2 days, but this is not true for strawberries, likely due to the acidity of the berry⁹.
What does it mean for us?
Choose cotton and other more absorbent material to wear when you have to go to a hospital or public places to minimize the transferring of the virus.
Paper receipts are likely safer than coins and money. However, after you reach used the credit card, remember to clean up and wash your hands thoroughly.
If it is safe to do so, clean non-absorbent non-porous material, such as reusable plastic or polyester bags, after coming from or going to (especially if there is a household member who was or is currently infectious) public places. If not possible, leave the material undisturbed for at least a few days, and preferably under UV light (like sunlight), in higher temperature places before touching them or bringing them out again.
When possible, clean plastic or stainless steel shared public items thoroughly, such as shopping cart handles, before using them.
Cook your food thoroughly if possible for a prolonged period. If it can not be heated up, clean thoroughly before and consider employ consumable acidic condiments, such as vinaigrette, for safer consumption.
Last but not least, perhaps copper items will come back in fashion and acidic ice cream will become popular. If you are like me, you may start to wear cotton pants in public.
References:
1. Marquès, M., & Domingo, J. L. (2021). Contamination of inert surfaces by SARS-CoV-2: Persistence, stability and infectivity. A review. Environmental Research, 193(November 2020). https://doi.org/10.1016/j.envres.2020.110559
2. Riddell, S., Goldie, S., Hill, A., Eagles, D., & Drew, T. W. (2020). The effect of temperature on persistence of SARS-CoV-2 on common surfaces. Virology Journal, 17(1), 1–7. https://doi.org/10.1186/s12985-020-01418-7
3. Taylor, D., Lindsay, A. C., & Halcox, J. P. (2020). correspondence Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1. Nejm, 0–2.
4. Akram, M. Z. (2020). Inanimate surfaces as potential source of 2019-nCoV spread and their disinfection with biocidal agents. VirusDisease, 31(2), 94–96. https://doi.org/10.1007/s13337-020-00603-0
5. Ren, S. Y., Wang, W. B., Hao, Y. G., Zhang, H. R., Wang, Z. C., Chen, Y. L., & Gao, R. D. (2020). Stability and infectivity of coronaviruses in inanimate environments. World Journal of Clinical Cases, 8(8), 1391–1399. https://doi.org/10.12998/WJCC.V8.I8.1391
6. Biryukov, J., Boydston, J. A., Dunning, R. A., Yeager, J. J., Wood, S., Reese, A. L., … Altamura, L. A. (2020). Increasing Temperature and Relative Humidity Accelerates Inactivation of SARS-CoV-2 on Surfaces. MSphere, 5(4), 1–9. https://doi.org/10.1128/msphere.00441-20
7. Chin, A. W. H., Chu, J. T. S., Perera, M. R. A., Hui, K. P. Y., Yen, H.-L., Chan, M. C. W., … Poon, L. L. M. (2020). Stability of SARS-CoV-2 in different environmental conditions. The Lancet Microbe, 1(1), e10. https://doi.org/10.1016/s2666-5247(20)30003-3
8. Oakenfull, R. J., & Wilson, A. J. (2020). Qualitative Risk Assessment: What is the risk of food or food contact materials being a source or transmission route of SARS-CoV-2 for UK consumers?, 1–21. Retrieved from https://www.food.gov.uk/sites/default/files/media/document/web-version-qualitative-risk-assessment-risk-of-food-or-food-contact-materials-as-transmission-route-of-sars-cov-2-002.pdf
9. Anelich, L. E. C. M., Lues, R., Farber, J. M., & Parreira, V. R. (2020). SARS-CoV-2 and Risk to Food Safety. Frontiers in Nutrition, 7(November), 1–8. https://doi.org/10.3389/fnut.2020.580551
10. https://fortune.com/2020/06/15/china-coronavirus-beijing-outbreak-salmon/
