Fig. 10 Pulmonary abscess. Contrast-enhanced axial CT of the chest...

What To Know About Rising Tuberculosis Cases In The U.S.

After declining for three decades, tuberculosis (TB) rates in the U.S. Have been increasing steadily since 2020, according to a Centers for Disease Control and Prevention report from the end of 2024. It's a disturbing trend given that 1.5 million die from TB every year, making it the world's most infectious killer.

Now a recent outbreak in Kansas City, Kansas, has gained national attention and concern. Though the Centers for Disease Control and Prevention has since refuted claims that this is the largest outbreak in recorded U.S. History, the numbers are still historically high: As of January 24, two people have died from TB, 67 are being treated for active infections, and another 79 have latent infections.

Nationwide, 2023 saw the highest number of cases reported in the last decade. Most of these recent cases are not instances of novel transmission, but sudden activation of latent infections that were undetected or improperly treated.

While TB impacts thousands nationally and millions around the world, "most people in the U.S. Are not at risk of developing TB," says Philip LoBue, director of the CDC's Division of Tuberculosis Elimination. 

Compared with high TB incidence countries like India, China, and the Philippines, the chance of infection in the U.S. Is still one of the lowest in the world. But the recent trend reversal has raised questions—and some alarm bells—among infectious disease and public health experts. Here they offer insight into the causes and implications of the latest outbreak and sudden upswing in cases.

What is tuberculosis, and why is it so serious?

Tuberculosis is one of the oldest and deadliest diseases in human history. For millennia, the infection has afflicted people around the globe, earning ominous nicknames like "the white plague," "consumption," and even "the robber of youth." A century and a half ago, TB was essentially a death sentence—roughly 80 percent of active infections were fatal. Since then, rates have been on the decline in the U.S. And abroad, thanks to new vaccines, diagnostics, and antibiotic treatments.

The disease is caused by a highly contagious bacterial infection that primarily affects the lungs but can also damage the kidneys, heart, bones, joints, and blood vessels. If it spreads, it can cause meningitis, swelling of the brain and spinal cord, or hepatitis, inflammation of the liver.

"Even the people who don't die of the disease, they're hospitalized [and] have a lot of long-term problems from having TB," says Priya Shete, associate medical professor and co-director of the University of California, San Francisco Center for Tuberculosis.

TB transmits through prolonged exposure to infectious airborne particles, such as from coughing or sneezing. A person infected with TB often does not display symptoms or know they're sick for weeks or even years—called a "latent" infection. But the infection may become active, and contagious, at any time. 

Even if the bacteria is detected and an effective antibiotic is prescribed, the treatment regimen is long—several months—which makes patient compliance difficult. 

"We need constant surveillance and suppression to keep TB in a latent form," says Jeffrey Cox, professor of immunology and pathogenesis at University of California, Berkeley. "If you remove that pressure, the bacteria can then start growing again."

While both preventable and curable, TB remains a leading infectious killer worldwide, claiming over a million lives every year. The disease affects millions in every country and age group, but hits particularly hard in low- and middle-income populations.

Why are TB rates rising in the U.S.?

From a public health perspective, it's no surprise that tuberculosis counts have been on the rise since 2020. When the pandemic hit, reporting of other communicable diseases like TB initially plummeted as the majority of resources went towards COVID. 

"Most countries actually had a dip [in cases] from 2019 to 2020," Cox says. "But that doesn't mean that TB went down."

In fact, the pandemic-era emphasis on coronavirus tracing and treatment may have allowed TB infections to multiply unchecked. 

"A lot of those lower priority activities of health care—maintenance and prevention—were deferred," says Shete. "We weren't doing a great job prioritizing TB prevention."

Cox describes a sort of snowball effect: If people don't get tested or report infections, they don't get the treatment they need and can transmit the infection to others. Waning mask-wearing and increased travel can also exacerbate the spread.

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Compared with previous caseloads, new TB patients are "often more sick at the time that they're diagnosed," Shete says. During the pandemic, some physicians may have misidentified or failed to take their symptoms seriously. "It can be kind of the slow burn of a disease where people start to lose weight, they start to feel crummy, they have a chronic cough, and maybe not seek care as quickly."

LoBue agrees, citing "the similarity of pulmonary TB disease and COVID-19 symptoms" and disrupted health care access during the pandemic as key factors in the initial drop, then rise, in cases. 

As before the pandemic, most recent cases—a whopping 80 percent—occur when untreated, latent infections become active. This most often happens to people whose immune systems are weakened, particularly from diseases like HIV or certain immune-suppressing medications, according to LoBue. In contrast, a healthy immune system could keep the infection at bay indefinitely.

As for the Kansas City outbreak, officials have yet to determine its exact cause, but Cox says it points to the ever-present threat of TB in dense urban areas—even in low-risk countries. 

"TB is not going away. It might be low here, but it's all over the world," he says. "There's going to be invariable flare-ups from time to time." And in places like the U.S. Where TB is not endemic, he adds, "it can spread like wildfire."

Cox, for his part, is most concerned about potential drug resistance. The worst case scenario, he says, is if experts determine that patient zero carried an antibiotic resistant strain of TB, which would complicate treatment. Still, he echoes local health officials who assert that the risk to the general public is "very low." While Cox understands concern within the immediate Kansas metropolitan area, he says the odds of it spreading further are slim. "There's no reason to panic right now."

Who's most affected by tuberculosis? 

Within the U.S., those most susceptible to TB continue to be people born in, or frequent visitors to, countries where TB is common, working or living in riskier settings like schools and high-density housing, or those with weaker immune systems, according to Shete.

"Tuberculosis, just generally speaking, is often called a 'disease of poverty,'" she says. People experiencing food insecurity, poor access to basic health services, and inadequate or crowded living conditions are at higher risk of infection and often lack the resources for testing or treatment.

Of people born in the U.S., TB rates are highest among those "who have historically been minoritized or marginalized, socioeconomically or racially or ethnically," Shete says, including Black and Latinx populations. According to the latest CDC report, Black Americans represented the largest number—33 percent—of U.S.-born TB cases, followed by Hispanic and white Americans. 

Still, Cox emphasizes that national numbers "pale in comparison" with the rest of the world. And whether the increased cases are just a "blip" or continue to trend upwards remains to be seen. "Until we have more years of data, we can't say for sure," agrees the CDC's LoBue.

What are the larger implications of these rising rates?

Experts urge people to stay informed about TB, without raising unnecessary alarm. Shete says it's important to remember it's fully preventable, diagnosable, and treatable.

Those outside of high-risk groups generally don't have to worry unless they notice symptoms or are exposed to someone with an active infection. That said, Shete adds, "I hesitate to make it less important to most people only because it just takes one person in your community to have TB."

The greater burden falls on healthcare professionals and the public health system. Particularly among high-risk populations, Shete says that physicians should regularly screen for TB. These preventative measures should be included in Medicare coverage, which is not always the case. Just last year, the U.S. Preventive Services Task Force issued a recommendation for screening asymptomatic adults at increased risk of latent tuberculosis infection for the first time since 2016.

Long-term management of TB cases will require ongoing investment in clinical research and the development of more effective diagnostics and antibiotics, Cox says.

"It does take that kind of infrastructure and constant surveillance and funds from the government to keep those programs going," Cox says. 

Ultimately, the risk of TB for U.S. Residents is mercifully low. But effective mitigation of the infection at home relies on attacking it on a global scale. The U.S. Has made this a priority, through international programs like USAID's Global TB Strategy and the CDC's Division of Global HIV & TB, which is working to combat the two epidemics simultaneously. 

As Shete says, "Whatever is happening in the world is going to affect us too in the U.S."

This story was originally published in May 2024 and has been updated.

A TB Outbreak In Kansas Is Growing, As US Rates Rise Too. What Are The Symptoms?

Kansas is dealing with one of the largest outbreaks of tuberculosis recorded in a single year in the United States since the 1950s, state health officials say. The outbreak in the Kansas City area has sickened dozens and killed at least two people since it began last January.

On Monday, Jan. 27, the Kansas Department of Health and Environment said the tuberculosis outbreak is still ongoing and "there could be more cases" as it grows.

Tuberculosis, also known as TB, is an infectious disease that primarily affects the lungs. TB is a serious infection that if left untreated can be fatal.

As of Jan. 24, at least 67 people are being treated for active TB related to the Kansas outbreak, Jill Bronaugh, communications director of the KDHE, said in an update on Jan 29. Additionally, the outbreak killed two people in 2024.

Although state health officials say the risk to the general public is low, the current outbreak in Kansas is unprecedented. The situation in Kansas, along with other recent TB trends in the U.S., has sparked some concern among experts. Here's what to know.

Is tuberculosis a virus?

No, tuberculosis is not caused by a virus. Tuberculosis is an infectious disease caused by the bacterium Mycobacterium tuberculosis, according to the U.S. Centers for Disease Control and Prevention. Tuberculosis usually affects the lungs, but it spread to the brain, spine, and kidneys.

Not everyone infected with the bacteria that causes TB will get sick, which is called a latent or inactive TB infection.

People with latent TB do not develop symptoms and aren't contagious, so they can't spread the infection to others. However, people with latent TB can still develop active TB at any time.

When the bacteria multiply and cause symptoms, this is called active tuberculosis disease or active TB. People with active TB can spread the infection to others.

Although it's controlled in the U.S., tuberculosis is the leading infectious disease killer worldwide. Globally, TB causes millions of illnesses and deaths every year, per the World Health Organization.

Kansas City tuberculosis outbreak

Since January 2024, the Kansas Department of Health and Environment has confirmed 67 active TB cases involved in this outbreak, including 60 in Wyandotte County and seven in neighboring Johnson County. Additionally, there have been 79 latent TB cases reported in these two counties.

At least two people have died in this outbreak. The state's health department has not released any additional details to the public.

Last year, the KDHE reported 79 active TB and 213 latent TB cases, both involved in this outbreak and sporadic (non-outbreak), says Bronaugh. However, the 2024 case counts are still provisional, and will be confirmed by the CDC at the end of March, she notes.

"While this outbreak is larger than normal, the risk remains low for the general public," says Bronaugh.

Is this the largest TB outbreak in U.S. History?

The total cause count associated with the current outbreak in the Kansas City Metro area (67) makes it "the largest outbreak in the U.S. At this time over the span of one year since the CDC began reporting TB cases in the 1950s," says Bronaugh.

In an earlier statement on Monday, Jan. 27, state health officials said the current outbreak was "the largest documented outbreak in U.S. History" since the 1950s.

However, a CDC spokesperson rebutted this claim, pointing to two recent tuberculosis outbreaks in the U.S. Involving a larger number of cases, NBC News previously reported. These include an outbreak in Georgia at homeless shelters from 2015 to 2017, and a nationwide outbreak linked to contaminated bone grafts in 2021.

While not the largest outbreak in U.S. History, the current outbreak in Kansas is still large enough to raise some alarm, experts say. The state usually only sees a handful of TB cases each year. In 2023, the CDC recorded 46 active TB cases in Kansas, says Bronaugh.

"It's a substantial outbreak of tuberculosis," Dr. William Schaffner, professor of infectious diseases at Vanderbilt University School of Medicine, tells TODAY.Com.

Tuberculosis rates in the U.S. Are generally very low, says Schaffner, largely thanks to vigorous state TB control programs. However, after declining steadily for 30 years, tuberculosis rates increased each year from 2020 to 2023, according to the latest CDC data.

The KDHE has not released details about the populations affected by the outbreak. "Of course, that's intriguing and we would like to know that from a public health point of view," says Schaffner.

The health department said it is working with the CDC to track the outbreak and prevent further spread. "KDHE is currently managing a total of 384 individuals associated with this outbreak who are all at various different stages of TB testing, diagnostics and treatment," says Bronaugh.

It's unclear how the Kansas TB outbreak will pan out, but cases are expected to grow. "It is important to note that this outbreak is ongoing, therefore, cannot be compared to previous TB epidemics or outbreaks," says Bronough.

TB transmission

Tuberculosis spreads from person to person through the air, when a person with active TB talks, coughs, sneezes, laughs or sings.

These germs can linger in the air for hours, especially in closed, indoor spaces, per the CDC. People become infected when they inhale the germs, which then settle in the lungs, says Schaffner.

Transmission of tuberculosis requires close, prolonged contact with someone who has active TB disease. "It's not transmitted casually by fleeting contacts," says Schaffner, adding that it's not readily transmissible like influenza or COVID, for example.

TB germs are not spread by shaking someone's hand, kissing, sharing food or drinks, or touching toilet seats, per the CDC.

People with latent TB are not contagious and cannot spread the infection to others. However, they are still treated to prevent a recurrent active TB infection later on, which can be contagious.

Signs of tuberculosis

According to the CDC, symptoms of active tuberculosis include:

A cough lasting at least three weeks

Chest pain

Fatigue

Coughing up sputum or blood

Fever

Weight loss

Night sweats

People with inactive or latent TB will not develop symptoms, unless they develop active TB.

"The hibernating bacteria in those individuals can recur and cause illness in that person, 10, 15, 20 years later," says Schaffner.

If left untreated, about 5-10% of latent cases will develop into active tuberculosis disease, according to the CDC.

Tuberculosis treatment

Tuberculosis patients, both active and inactive, are treated with antibiotics. Treatment typically involves taking multiple antibiotics every day over a period of four to nine months, per the CDC.

There is a vaccine for tuberculosis, which is not generally used in the U.S., but instead given to young children in countries where tuberculosis disease is common.

Kansas Tuberculosis Outbreak One Of Largest Ever In US

An unprecedented tuberculosis (TB) outbreak in Kansas has reached historic levels, becoming one of the largest ever recorded in U.S. History.

The Kansas Department of Health and Environment (KDHE) has reported 67 active cases since 2024, with 60 in Wyandotte County and 7 in Johnson County.

Additionally, 79 latent infections—77 in Wyandotte County and 2 in Johnson County—have been identified.

"Currently, Kansas has the largest outbreak that they've ever had in history," Ashley Goss, a deputy secretary at the Kansas Department of Health and Environment (KDHE), told the Senate Public Health and Welfare Committee on January 21, according to the Topeka Capital-Journal.

A KDHE spokesperson later clarified the statement, explaining that the current outbreak "is the largest documented outbreak in U.S. History." Newsweek contacted the KDHE via email for further comment.

However, the CDC has refuted this assertion, pointing to two larger TB outbreaks in the U.S. In recent history.

One, which spread through homeless shelters in Georgia between 2015 and 2017, saw 170 active and more than 400 latent cases recorded.

The other, a nationwide outbreak in 2021 that was linked to contaminated tissue used in bone transplants, affected 113 patients.

A stock photo of a doctor examining chest x-ray film in a medical laboratory at a hospital. A stock photo of a doctor examining chest x-ray film in a medical laboratory at a hospital. Amorn Suriyan/Getty Why This Matters

TB, though treatable, remains a serious infectious disease that can lead to complications and fatalities if untreated. The Centers for Disease Control and Prevention (CDC) estimate 13 million Americans live with inactive TB and about 10 percent of these individuals could develop active TB without treatment.

The sharp rise in TB cases—from 51 statewide in 2023 to 109 in 2024—has placed a spotlight on public health measures. Kansas health officials are actively working to contain the outbreak, partnering with the CDC to prevent further transmission.

What to Know

TB is caused by bacteria that primarily attack the lungs but can affect other parts of the body. The infection spreads through the air via coughs or speech but requires prolonged contact for transmission.

Active TB disease makes individuals sick and is infectious, while latent TB infections are dormant, non-contagious and symptom-free but can become active.

Treatment is available for both active and latent TB infections and involves a several-month regimen of antibiotics. Active TB patients are typically non-contagious after 10 days of treatment.

Wyandotte County has been the hardest hit, but health officials maintain that the general public remains at "very low risk."

What People Are Saying

Goss told the Senate Committee: "Some of you are aware, we have and still have mobilized staff and resources addressing an unprecedented tuberculosis outbreak in one of our counties. We are working collaboratively with CDC on that. CDC remains on the ground with us to support. That's not a negative.

"This is normal when there's something unprecedented or a large outbreak of any kind, they will come and lend resources to us to help get a stop to that."

What Happens Next

Kansas health officials and the CDC are continuing their collaborative response to the outbreak.

Their efforts include identifying and testing individuals who have been in close contact with TB patients and ensuring that both active and latent cases receive proper treatment.

Vaccinations for TB are available in the U.S., though they are seldom used, according to the CDC.

For now, Goss said that infections are "trending in the right direction."

Is there a health problem that's worrying you? Do you have a question about low blood pressure? Let us know via health@newsweek.Com. We can ask experts for advice and your story could be featured in Newsweek.

Correction 01/31/25, 5:30 a.M. ET: This article was updated to reflect the fact that the current TB outbreak in Kansas is not the largest in U.S. Record, according to the CDC.

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