The Future of Food Safety

Human Wrongs Watch

How whole genome sequencing is helping decode the risks to our food

Food trade can improve the availability of nutritious food and compensate for poor harvests or other disruptions in food supply. Yet, with heightened global trade, there are an increasing number of challenges in keeping food safe. ©bee cappy/shutterstock.com | Photo from FAO.

20 April 2019 (FAO)* — Food is evolving. Meal-replacement beverages, 3-D printed pasta and meat grown in laboratories… These are just some of the paths it is taking. Whatever our take on it, as food changes, so will our need to define its safety.

For food to be food, it needs to be safe. Nutritious food provides us with the energy and nutrients we need to be healthy and active. To do that, our food must pass tests demonstrating that it does not contain levels of toxins or microorganisms that would harm us.

Every year, over 420 000 people die and some 600 million people around the world become ill after eating contaminated food.

With heightened global trade, there are an increasing number of challenges in keeping food safe as it travels vast distances and across borders. Yet, food trade is a useful and regular part of our world, which benefits both importing and exporting countries. International trade can improve the availability of nutritious food and compensate for poor harvests or other disruptions in food supply.

It can also help support and increase jobs for food producers. A foodborne illness outbreak can disrupt or destroy the livelihoods of thousands of people. Making sure food is produced and handled in a way that keeps it safe throughout the entire supply chain protects people’s health, safeguards people’s jobs and creates a level playing field for trade.

When foodborne illnesses happen, it is the job of health officials to track down the common denominators of the outbreak and find the source of contamination. No easy job. But new scientific tools are making it faster and more effective. One major scientific advance in particular, Whole Genome Sequencing (WGS), can track down pathogens by reading their gene combinations.

WGS is a technique that reads genetic information, potentially unveiling a distinct sequence by which to recognize specific microorganisms. These DNA sequences are like fingerprints. They are unique to each organism and its strain, and as such, this WGS technique can track down pathogens with precision not previously possible.

Here are four ways that WGS is helping us track down the culprit pathogens and keep our food trade flowing: 

1. WGS can help single out with more precision which ingredient in a multi-ingredient food is responsible for an outbreak. When you eat an egg and get sick, you know it is the egg. But what happens if you get sick from a quiche? Is it the eggs, the butter, the milk or another ingredient? WGS can detect with more precision than conventional methods which specific ingredient carried the pathogen.

2. WGS can determine the source of contamination. Knowing at what point in the food chain the food was contaminated stops us from inadvertently blaming restaurants or other businesses that are at consumer-level. For example, in June 2014, there was a large multi-country outbreak of Salmonella seemingly linked to the consumption of eggs. There were over 350 cases in several European countries.

By taking samples from five restaurants in England, WGS proved that the cases were distinct but linked. More WGS of samples from several European countries showed that separate introductions of contamination had occurred from a single European egg producer.

3. WGS can help determine which illnesses are part of an outbreak. When outbreaks happen, it is very hard to know if the cause of one person’s sickness is the same cause as someone else’s, especially if they are in different parts of the country. With genome sequencing, it is easier to tell what the pathogen is and the type of illness it can cause.

4. WGS can more definitively show the linkages between multi-national outbreaks. The Salmonella in eggs case mentioned above also highlights the importance of making genome sequencing data available across multiple countries. Global sharing of WGS data could enhance the response to a foodborne outbreak and to stop it from spreading further.