A man kneels down to take the laundry out of his washing machine.
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The new coronavirus, SARS-CoV-2, is what causes the respiratory illness COVID-19. While COVID-19 is often mild, it can sometimes result in serious illness.

Because of this, there’s been ongoing investigation into ways to effectively kill the new coronavirus. One of the topics that’s been discussed is high temperature.

Let’s take a closer look at what temperature kills SARS-CoV-2, the steps you can take at home to kill the coronavirus, and the myths regarding ways to kill the virus with high temperature.

It’s known that exposure to high temperatures can kill coronaviruses. In fact, inactivation of SARS-CoV-2 on surfaces speeds up as temperature and humidity increase.

However, the exact temperature and time it takes to kill the virus can vary depending on various factors. These can include things like the amount of virus that’s present as well as the surface type.

It’s important to keep this point in mind as we review some of the research into this topic.

To estimate the temperature that could kill SARS-CoV-2, one group of researchers looked into the effect of temperature on other coronaviruses. One of these viruses was SARS-CoV, which causes SARS and is closely related to SARS-CoV-2.

Based off the data, the researchers estimated that most coronaviruses would be almost completely killed after exposure to temperatures of 65°C (149°F) or higher for longer than 3 minutes. The researchers also noted that:

  • For temperatures lower than 65°C (149°F), a longer exposure time should be used. For example, the coronavirus may need to be exposed to temperatures of between 50 and 55°C (122 to 131°F) for 20 minutes to be killed.
  • To ensure that all coronavirus particles are killed, it may be beneficial to increase the temperature by 10°C (18°F). This would mean heating the virus to 75°C (167°F) for at least 3 minutes.

This recommendation is generally in line with observations from other studies on this topic:

  • A study published in The Lancet Microbe looked at how temperature affected high amounts of SARS-CoV-2 in laboratory media. The researchers found that the virus was killed after 5 minutes at 70°C (158°F).
  • One study in Applied Physics Letters used mathematical modeling to predict the effect of different temperatures on SARS-CoV-2. The model estimated that the virus would be killed after an average of 2.5 minutes at 70°C (158°F).
  • A study in Emerging Infectious Diseases assessed different ways to decontaminate N95 respirators. The researchers found that temperatures of 70°C (158°F) killed the new coronavirus on N95 respirators after about 1 hour.
Summary

Generally speaking, it appears that a temperature of around 70°C (158°F) is effective at quickly killing SARS-CoV-2, the new coronavirus.

However, the time it takes to completely kill the virus can depend on the amount of virus present and the type of surface that it’s on.

Now that we’ve discussed what temperatures can kill the new coronavirus, you may be wondering how can you implement this into daily activities that involve temperature, such as laundry and cooking.

First, it’s important to note that many of the temperatures we’ve discussed above are warmer than residential hot water or the temperatures used in a washing machine or dryer. They’re also higher than many recommended cooking temperatures.

While your washer and dryer may not reach 70°C (158°F), the combination of heat and detergent products can work together to effectively eliminate SARS-CoV-2 on fabrics.

To wash potentially contaminated fabrics, including cloth face coverings, do the following:

  • Use the warmest water setting that’s suitable for the fabrics you’re washing.
  • Select a detergent or bleach-based product that’s appropriate for the items.
  • Place fabrics into the dryer promptly after the washing cycle. Be sure to use high heat, and make sure all items are completely dry before removing.
  • Try to wear gloves when handling fabrics that may be contaminated with the virus. Always wash your hands after handling potentially contaminated laundry.

The likelihood of getting COVID-19 from food that you cook yourself or that you get from a restaurant is very low.

According to the Centers for Disease Control and Prevention (CDC), there’s no evidence that food or food packaging is associated with the spread of COVID-19.

If you have concerns about contaminated food packaging, don’t use household cleaners on foods packaged in cardboard or plastic wrap. Instead, wash your hands thoroughly after handling these items.

Generally speaking, using high temperature isn’t the most effective or safest way to kill SARS-CoV-2 that may be present on surfaces.

In the section below, we’ll explain how to best kill the new coronavirus on common household surfaces.

Above, we looked at ways to kill the new coronavirus on fabrics and in food. Now let’s go over some tips to kill this virus on common household surfaces:

  • Use an EPA-registered disinfectant. The Environmental Protection Agency (EPA) maintains of list of disinfectants that can effectively kill SARS-CoV-2.
  • Use bleach. A homemade bleach solution can be used to disinfect some surfaces, and can be used for up to 24 hours. You can make a bleach solution by mixing 1/3 cup of household bleach in 1 gallon of room temperature water.
  • Follow the label instructions. Carefully following all label instructions can help ensure that you effectively eliminate any virus that’s present on surfaces. Information on the label to look out for includes:
    • appropriate surfaces for the product
    • how much to use
    • contact time
    • precautions or safety warnings
  • Focus on high-touch surfaces. You don’t need to disinfect every surface in your house. Instead, zero in on things you come into contact with frequently and are more likely to be contaminated. Some examples are:
    • doorknobs
    • toilets
    • sinks, including the faucet handles
    • light switches
    • flat surfaces, such as countertops, tabletops, and desktops
    • appliance handles, such as on the refrigerator or oven door
    • TV remotes and video game controllers
    • touch screens on phones or tablets
    • keyboards and computer mice
  • Use care with electronics. Check the manufacturer’s instructions for specific directions before disinfecting electronics. If instructions aren’t available, you can disinfect these items by using 70 percent ethanol.
  • Mind your hands. Plan to wear gloves while disinfecting. When you’ve finished, be sure to wash your hands thoroughly.

You may have heard about some other possible heat-related methods to kill the new coronavirus and wondered whether they would work. Let’s take a closer look at some strategies that won’t help eliminate this virus.

Exposing yourself to high temperatures

You can’t prevent COVID-19 by exposing yourself to high temperatures, such as:

  • taking a hot bath or shower
  • sitting in a sauna or hot tub
  • using hot air from a hand dryer or hair dryer

These methods are unlikely to produce the temperatures needed to effectively eliminate SARS-CoV-2.

Instead of killing the virus, they can actually be harmful, especially at higher temperatures, and could potentially burn or scald your skin.

Spending extended time in the sun

You may have heard that warm weather and UV light can kill germs, including viruses. However, soaking up the sun to prevent COVID-19 isn’t a good idea.

The types of UV light in sunlight (UVA and UVB light) aren’t as effective at killing germs. Additionally, prolonged sun exposure can cause skin damage, sunburns, and possibly skin cancer.

Wiping down household surfaces with hot water

The water from your tap won’t be hot enough to kill the new coronavirus. However, using unheated soapy water will be enough to kill the virus.

Boiling tap water to use for cleaning purposes can potentially cause burns or scalds, and may damage some types of surfaces.

SARS-CoV-2, the new coronavirus that causes COVID-19, is sensitive to high temperatures.

Research shows it can be quickly killed at 70°C (158°F). It’s possible that slightly lower temperatures may also be effective, but these require a longer exposure time.

Aside from laundry, there aren’t many temperature-related ways to safely and effectively kill the new coronavirus in your home. Additionally, some temperature-related methods can actually be harmful.

To eliminate SARS-CoV-2 in your home, focus on regularly disinfecting high-touch surfaces, and washing your hands after being in public.