- Researchers discovered that people who suffer from acid reflux and Barrett’s esophagus are at risk of contracting the novel coronavirus in an unusual way via food.
- People suffering from Barrett’s esophagus develop intestinal cells in the esophagus following prolonged acid reflux. These cells have receptors that can bind to the coronavirus.
- However, there’s no evidence that people suffering from Barrett’s have higher rates of contracting COVID-19 or are at greater risk than anyone else. But more research is required to determine the actual risk of infection in this category of patients.
More than a year has passed since the first infection with the novel coronavirus was confirmed, so most people should know how the virus spreads. Droplets and aerosols generated via coughing, sneezing, and talking can spread through the air and enter the upper airways of other people. The virus gains entry via the nose, mouth, or eyes, and starts spreading in local cells. Eventually, it reaches the lungs, which is where it does the most damage.
That’s why face masks, social distancing, hand washing, and proper ventilation of indoor spaces are advised. There’s also the risk of infection by touching contaminated surfaces, although it’s droplets and aerosols that are the main drivers of infection. But researchers from the Washington University School of Medicine in St. Louis hypothesize that some people might be at risk of infection in an unusual way: Eating food.
In the early days of the pandemic, we learned that food doesn’t spread COVID-19. The virus binds to ACE2 receptors in the nose and lungs, but not in the digestive tract. Stomach acid can destroy particles that might be present in food. Cooking the food will also destroy the virus. Health experts still advised people to wash their hands often when handling food items brought home before preparing meals or handling deliveries. In the months that followed, health authorities, including the WHO, further emphasized the idea that transmission via food packaging is unlikely.
The researchers in St. Louis discovered something that doesn’t apply to all people who might be exposed to the virus. They studied patients who suffer from a condition called Barrett’s esophagus and develop esophageal cells that can bind to the novel coronavirus.
Acid (or gastric) reflux can cause long-term damage to the esophagus, including the modifications of cells that start resembling intestinal cells. These cells come with ACE2 receptors, so the virus could bind to them while traversing the esophagus.
“There is no evidence yet that people with Barrett’s esophagus have higher rates of COVID-19 or are at any greater risk, but part of the reason is because that hasn’t been studied,” Dr. Jason C. Mills said in a statement. “Now that we’ve connected these dots, it may be worthwhile to look and see whether people with Barrett’s have higher rates of infection.”
People suffering from Barrett’s esophagus routinely take a type of drug called proton pump inhibitors to suppress acid secretions. As a result, the stomach’s acidity is reduced, which could have another side-effect. More viruses might pass through the stomach and then bind to receptors in the intestine.
About one in five people in the US suffer from gastric reflux, but that doesn’t mean they’re all at risk of contracting the virus from food. The researchers have shown via lab experiments that the virus can bind to modified cells in the esophagus, but that’s not proof that it’s actually happening in real life. It’s also unclear what would happen if a person suffering from Barrett’s were to contract the virus via food only, but not the airways.
However, the researchers point out that if a person already has low levels of virus in their respiratory tract, they might swallow secretions containing the virus, which would bind to the anomalous cells in the lower portion of the esophagus. This might make them sicker, but these are all speculations that need further research. What the scientists proved so far is that the virus can indeed bind to esophageal cells in Barrett’s
Many COVID-19 patients do develop gastrointestinal symptoms, including abdominal pain and diarrhea. But it’s unclear whether Barrett’s could impact these symptoms or increase the severity of COVID-19.
“The worry would be that, particularly for Barrett’s patients, there even may be a susceptibility to infection from foods containing viral particles,” Mills said. “This study provides data to indicate that we need to take a closer look to investigate whether a substantial portion of the population may be susceptible to infection through what they swallow.”