SDSU researcher warns COVID-19 could cause spike in tuberculosis cases

TB is one of the leading causes of death worldwide
Posted at 6:22 PM, Sep 22, 2020

SAN DIEGO (KGTV) — An infectious disease expert at San Diego State University says early research suggests the COVID-19 pandemic could cause a spike in another, more deadly respiratory disease: tuberculosis.

An estimated one in four people on the planet is already infected with TB without knowing it. The bacterium that causes the disease can lie dormant for years, even decades, waiting for the right moment to strike.

San Diego State University professor Dr. Faramarz Valafar says SARS-CoV-2, the virus that causes COVID-19, could be just the right pathogen to trigger more TB cases to activate, both worldwide and in the U.S. And the symptoms of COVID-19 could help spread the TB bacteria more efficiently.

“COVID-19 could act as a vehicle for transmission of tuberculosis,” he said. “This is a significant public health risk.”

In the early 1900s, TB was the number one cause of death in the U.S. Today, it remains one of the top 10 causes of death worldwide with about 1.5 million deaths each year, although deaths in the U.S. are now rare. There were 515 deaths in the U.S. in 2017, the most recent data available.

Although the tuberculosis is mostly curable and preventable with antibiotics, some strains have become drug-resistant.

“I believe it's naive to think that because there is not much tuberculosis here in the United States, it’s going to remain that way,” said Valafar. “We now have a vehicle for the transmission of all sorts of tuberculosis strains from around the world to the United States.”

The CDC estimates up to 13 million people in the U.S. have latent TB. Studies have shown the disease can activate when the immune system is weakened, including by HIV.

“If COVID-19 comes in and keeps the immune system busy or overburdened, then my first worry is that tuberculosis in those people could activate,” he said.

A small study out of China that has not yet been peer-reviewed suggests people with latent TB are at a higher risk of developing severe COVID symptoms. Other experts have raised concerns about the pandemic could exacerbate TB infections.

Valafar said his second worry is that the symptoms of COVID-19 could help spread tuberculosis. Both pathogens take hold in the lungs and cause coughing.

“If the person has tuberculosis, all it takes is for COVID-19 to make that person cough or sneeze and there will be a much higher risk of tuberculosis transmission,” he said.

Valafar and his team are already studying the effects of TB and HIV in South Africa. They plan to soon expand their study to examine the effects of COVID-19 as well, with results expected in about a year.

In the meantime, he’s sounding the alarm to urge people to heed public health warnings. Masks, hygiene and social distancing don’t just protect against COVID-19. They protect against TB as well.

“It's so much more important that people really follow those instructions,” he said.