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Many of us use microwaves to warm or prepare food. In fact, according to a publication by the United States Department of Agriculture (USDA), over 90 percent of homes in the United States have at least one microwave.

During the coronavirus pandemic, much attention has focused on how to effectively kill the coronavirus on various surfaces. Because of this, you may have wondered if a microwave can kill coronavirus that may be present on food.

Overall, the answer to this question is maybe. Read on to learn more about microwaving, coronavirus, and safe food practices during the pandemic.

The answer to whether microwaves can kill the coronavirus is currently maybe. Let’s take a deeper dive into this topic.

What temperature kills the coronavirus?

You may be familiar with the concept of safe minimum cooking temperatures. This is the minimum internal temperature that a food needs to be cooked to in order to kill germs that can cause illness, such as bacteria and viruses.

For many types of food, the safe minimum cooking temperature is 165oF (74°C). However, this may be lower for some food types.

Studies have looked at temperatures that can kill SARS-CoV-2, the virus that causes COVID-19, in both laboratory media and on N95 respirators. They found that a temperature of 70oC (158oF) could kill the virus. The amount of time needed to achieve this varied by surface.

Based off of this information, can heating food to above 158oF (70oC) in a microwave kill the coronavirus? Let’s tackle this topic now.

Microwaves and coronavirus

Microwaves work by producing radio waves that are transmitted into the device at a specific frequency. These waves are absorbed by water molecules in the food, causing them to vibrate rapidly. These rapid vibrations produce the heat that cooks the food.

According to the Centers for Disease Control and Prevention (CDC), microwaves can be used to disinfect materials that are microwave-safe. They note that a home microwave may completely kill germs within 60 seconds to 5 minutes.

However, the total amount of time that this may take depends on the specific type of germ. The amount of power and time needed for microwaves to effectively kill SARS-CoV-2 is unknown at this time.

Additionally, there can be variations across different microwaves. Some may not cook at the same strength or in the same way. For example, the CDC warns that home microwaves may not cook with an even distribution.

This means that there could be areas of food where germs aren’t completely killed. Think of all the times you’ve tried to reheat leftovers and found that there are still cold spots in the food.

Viruses vs. bacteria

Unlike bacteria, viruses cannot grow (replicate) inside of food. They’re parasites that need a living host cell in order to make more of themselves.

Because of this, we focus on viruses that are present on the outside of food as opposed to the inside of food. Studies have evaluated how long SARS-CoV-2 can be found on various surfaces, including some common food packaging materials:

  • plastic: between 3 to 7 days
  • cardboard: up to 24 hours
  • glass: up to 4 days
  • paper: up to 4 days

According to the CDC, no cases of COVID-19 have been reported due to handling of food or food packaging. While disinfecting foods or food packaging is unnecessary, always wash your hands after handling these items and before eating.

Healthline

The pandemic has hit the restaurant industry particularly hard. That’s why ordering takeout food from your favorite restaurant is a great way to support them during this time. However, you may be wondering if ordering takeout is safe.

SARS-CoV-2 is mainly spread through the air. You can contract it if you breathe in respiratory droplets that are made when someone with the virus coughs, sneezes, or talks. Because of this, ordering takeout is relatively low-risk.

Takeout food handling tips

When you receive your takeout food, follow these steps to be sure that you’re handling it safely:

  1. Use your own utensils to carefully transfer the food from its packaging and onto a plate or tray.
  2. Promptly dispose of all food packaging, washing your hands thoroughly after doing so.
  3. Use your own eating utensils and napkins instead of those that were provided with the takeout order.
  4. Wash your hands again before eating.
  5. After you’ve finished your meal, clean your plates and eating utensils with soap and hot water or place them in the dishwasher. Then, wipe down the table or countertop that you ate on.

If the restaurant offers contactless curbside pickup, consider using this service. This will help limit the number of individuals, such as delivery people, that come into contact with your order.

As we touched on earlier, the microwave can be used to kill a variety of germs on microwave-safe surfaces. This may take seconds to minutes, depending on both the type of germ and the microwave.

However, remember that microwaves can vary in how much power they have and in how thoroughly they heat foods. Because of this, it’s important to check that food items are cooked to the proper internal temperature before eating them.

Kitchen sponges, germs, and microwaves

You may have heard of microwaving kitchen sponges to kill the germs on them. Indeed, a 2006 study found that a home microwave at full power killed test bacteria and viruses on kitchen sponges in a matter of minutes.

However, it may be a good idea to just toss an old kitchen sponge. This is due to a study from 2017 that evaluated the bacteria present on and in kitchen sponges.

The researchers found that regular sanitation of kitchen sponges, such as by microwaving or boiling, actually increased the number of certain types bacteria that are more resistant to sanitation.

Why you shouldn’t microwave masks or books

You may have seen information about using microwaves to disinfect N95 respirators or other personal protective equipment (PPE). It’s true that scientists continue to study this as a potential decontamination method for PPE.

However, it’s important to avoid microwaving your masks at home. This is because masks can contain materials that aren’t microwave-safe, such as cloth and metal. In fact, it’s possible your mask could catch fire in the microwave!

According to the CDC, reusable cloth masks can be cleaned in your laundry or by hand. The combination of warm water and laundry detergent can kill the virus. Disposable face masks need to be thrown away after each use.

Books are also a fire hazard in the microwave. Because cleaning a book with a disinfectant wipe can damage it, consider quarantining a book for a few days before using it. If you need to use the book sooner, wash your hands after handling it.

Healthline

Microwaves can kill different types of germs, such as bacteria and viruses. This can include SARS-CoV-2, although we don’t yet know what power and time settings are needed to achieve this effectively.

Additionally, remember that microwaves can differ in strength and how well they heat food. Because of this, germs in some parts of the food may not be killed.

Overall, the risk of contracting COVID-19 from food or its packaging is very low. However, it’s always important to practice good food safety measures in order to prevent becoming sick with a foodborne illness.