Coronavirus and Digestive Issues – What’s the Link?

‍What are the common symptoms of coronavirus?

The most common symptoms of coronavirus affecting the respiratory system (lungs, diaphragm, windpipe etc.) are:

• Dry cough
• Fever
• Shortness of breath (1)      

These develop in 99% of patients who contract the virus. (2) Less common symptoms of the virus include:

• Runny nose
• Headaches
• Fatigue
• Aches and pains
• Sore throat
  

How common are digestive symptoms in coronavirus?

Gastrointestinal (GI) symptoms are very common with coronavirus. A study from Wuhan, China, showed over 50% experienced digestive problems. These patients were admitted to the hospital with digestive problems such as nausea and diarrhea as their primary complaint. (3) Coronavirus causes GI symptoms such as:

• Loss of appetite
• Diarrhea
• Abdominal pain
• Nausea

The most common GI symptom of coronavirus was a loss of appetite, experienced by 84% of patients. Diarrhea was the second most common, in 29% of patients, and a smaller number reported vomiting and abdominal pain. (3)

Some coronavirus patients (less than 1%) suffered GI symptoms but no respiratory symptoms or fever. This was rare, however, as fever was common in almost 99% of cases. COVID-19 may cause a combination of respiratory and digestive problems, and should not be considered only as a condition of the lungs.

How does COVID-19 cause digestive issues?

Scientists do not know how the coronavirus causes gastrointestinal problems. However, three main theories have been put forward:

1) The virus binds to cells that signal the body to produce more liver cells, and the over-production of liver cells leads to inflammation and digestive problems. (4)

2) The virus causes an inflammatory response directly, and the chain reaction of inflammation affects the digestive tract to causes digestive problems. This is supported by viral DNA found in poo samples of patients (5, 6)

3) The virus disrupts ‘good’ bacteria in the intestines. These bacteria play important roles in digesting food, and disruption can cause symptoms of the digestive tract. (7)

The virus may also cause damage directly to the digestive system, however, more research is needed to clarify this point. (3)

Are digestive symptoms an early sign of Coronavirus?

Coronavirus may cause digestive symptoms that begin 2 days earlier than respiratory symptoms. Chinese scientists found that patients entered the hospital 9 days after digestive symptoms on average, compared to 7 days for respiratory symptoms. (3)

In response, scientists are recommending that doctors should test patients for digestive problems. Clinicians typically look for fever and cough to make a diagnosis, but adding an assessment of GI problems and testing stools can allow a diagnosis to occur earlier (8, 9)

On an individual level, those who develop unexplainable GI symptoms should consider self-isolating for 2-3 days and monitor the development of respiratory symptoms, to prevent infecting others before the onset of respiratory symptoms. By raising the ‘index of suspicion’ earlier, patients with coronavirus can be contained before the virus is able to spread further.

What kinds of GI tests for coronavirus are available?

A technology called reverse transcriptase-polymerase chain reaction (RT-PCR) has shown effective in testing for coronavirus. The test involves sampling genetic material (DNA) of the virus in poo samples to diagnose the infectious disease.

This technology is very useful in the midst of the coronavirus epidemic, as using it, 20% of patients were able to be diagnosed even after their respiratory tests were negative. This is because poo samples remain positive for the virus and detectable up to 14 days longer than respiratory tests. (8)

For patients who are suspected of having had coronavirus but are unsure, this technology can quickly identify whether they have had the virus in the past 14 days.

What is the prognosis of coronavirus with GI symptoms?

Patients with coronavirus who have digestive symptoms as well as respiratory symptoms have a worse prognosis (predicted outcome). This includes higher mortality rates and a lower likelihood of being cured and discharged from the hospital. In addition, these patients with digestive troubles were:

• More likely to suffer liver injury
• Show lower levels of immune cells (3)
  

Can coronavirus spread by the fecal-oral route?

You might have heard that coronavirus spreads from direct contact or cough droplets, with the highest risk within one meter of an infected individual (11).  However, the virus can also spread by the fecal-oral route, from the poo particles of one person to the mouth of another.

Scientists discovered this mode of transmission after isolating genetic material from poo samples of COVID-19 patients. This was a surprising finding since the virus predominantly affects the respiratory system. (13)

Is coronavirus more dangerous in people with IBD?

Patients with existing inflammatory bowel disease (IBD) may be at a higher risk of dying of coronavirus than others. This is because IBD patients often take medications that lower the immune system, essentially weakening the barriers between the body and the virus. (14)

However, doctors are recommending that those with IBD should still take current medications to prevent flare-ups of symptoms, but take extra care to avoid people with the virus. (15)

Do gastroenterologists need more protection?

Doctors who specialize in the digestive system – gastroenterologists – are at a high risk of contracting COVID-19. This is because of the close contact between these doctors and patients, allowing the virus to be transmitted along the fecal-oral route. (16)

In particular, procedures that involve inserting a flexible tube with a camera into the mouth or anus, such as colonoscopy or endoscopy are particularly dangerous. Therefore, gastroenterologists must wear personal protective equipment such as:

• A high-quality respirator
• Minimum of two pairs of gloves, one over the gown which covers the wrist
• Goggles and face shield
• Hairnet
• Long-sleeve, water-resistant gown. (16)
  

Other unusual symptoms of COVID-19

Besides gut problems, the coronavirus may cause other unusual symptoms. These include:

• Confusion: Malaise, disorientation or exhaustion is common symptom of COVID-19. Do not panic if experiencing these symptoms, however, as they may also be caused be stress or worry about the virus. (17, 18)
• Chills or muscle aches: These symptoms have been reported in 11 and 14 percent of COVID-19 patients respectively. (19)
• Headaches and dizziness: Dizzy spells or abrupt bouts of dizziness have been shown in 8 percent of coronavirus patients. The severity of the disease has been linked to the severity of headaches. (20)
  

Could digestive issues be IBS?

Digestive complaints during this pandemic may not always be caused by COVID-19. Numerous studies have shown short or long-term stress can cause digestive symptoms such as abdominal pain, constipation and diarrhea. Collectively these symptoms make up 'irritable bowel syndrome' (IBS). IBS affects 1 in 9 people globally and involves the following symptoms, some of which overlap with COVID-19:

• Abdominal pain (a symptom of COVID-19)
• Constipation
• Diarrhea (a symptom of COVID-19)
• Bloating

If you are unsure of whether you have IBS or early GI symptoms of coronavirus, it is important to consult a doctor. That way, proper isolation measures can be taken should you be diagnosed with COVID-19.

How can I keep safe during the Coronavirus pandemic?

To minimize the chance of coronavirus infection, the following precautions are recommended:

• Diligent hand washing (especially after contact with public spaces).
• Maintaining respiratory hygiene (e.g. using an arm to cover a cough or sneeze)
• Avoiding touching the face (in particular the nose, eyes and mouth)
• Avoiding large crowds (particularly in poorly ventilated areas) (21)
  

A Wrap Up

The coronavirus outbreak from the epicenter of the Hubei province in China has been labeled by the World Health Organization as a global pandemic. Research shows that up to half of COVID-19 patients experience gastrointestinal symptoms that begin, on average, 2 days prior to that of respiratory symptoms. As the number of coronavirus cases increases, it is important that clinicians and the public realize that the absence of respiratory symptoms does not guarantee the absence of COVID-19 infection. Although fever and respiratory symptoms such as dry cough and shortness of breath develop in most coronavirus patients, GI symptoms such as loss of appetite, diarrhea, and abdominal pain are the chief complaint in many of those that develop the virus. Monitoring symptom onset for GI symptoms for patients with suspect COVID-19 will allow for earlier diagnosis of COVID-19 and earlier treatment. The new coronavirus poses a higher risk of death than the routine flu and ongoing research will ensure new methods of diagnosis and treatment are discovered.