A Lurking Threat: Modern Tuberculosis in the SF Bay Area

Golden Gate Bridge in San Francisco, California, USA - Daytime

When the world’s spotlight is on Silicon Valley, visions of a tech-laced utopia arise. Self-driving cars are being tested, university researchers are developing hand-held medicine supergadgets, and San Francisco Bay Area residents are discussing the remaining scientific frontiers to cross—right? In the midst of all the progress lies a problem that can be overlooked: Mankind’s ancient malady, tuberculosis, is here with us in the 21st century. Ignoring it could set ourselves up for failure.

Tuberculosis may not be your first thought in the morning if you live in the United States. However, just a century ago this infectious disease was wreaking havoc as it had been for thousands of years. The most common form attacks the lungs, but it can also affect other parts of the body.1 Without treatment, tuberculosis can cause blood and fluid to fill the lungs which can make it difficult to breathe. Author Christian McMillen writes, “[Tuberculosis is] painful; it’s drawn out. It’s an awful way to die.”2

No one knew what caused it until Robert Koch identified a microscopic bacterium as the culprit and announced his discovery to a crowd of scientists on March 24, 1882. Koch’s work with tuberculosis earned a Nobel Prize in 1905. But over 50 years passed before medicine was developed for the disease.3

Before the advent of antibiotic drugs to treat tuberculosis, natural history studies estimate that up to 70% of people with the disease died within ten years. In total, this ancient disease has killed billions of people.1 One way to stop the spread was to send people with tuberculosis to isolated sanatorium facilities described by historian Sheila Rothman as “waiting room[s] of death.” Sending sick people away only added to the stigma of the disease.4

According to the World Health Organization, modern-day treatments have saved 49 million people from dying of tuberculosis worldwide just from 2000 to 2015.1 It can be easy for us to ignore infectious diseases when epidemic headlines aren’t blaring across all of the major news outlets. But tuberculosis (TB) is not just a problem of a past era. Natalie Shure, an American citizen, found this out in 2010 as a young Peace Corps volunteer.5


Fig. 1: Photo of a tuberculin skin test being administered.

Natalie’s diagnosis

During Natalie’s service abroad in the Ukraine, she had a routine tuberculin skin test as part of a medical check-up.5 The skin test works by administering a shot (made of tuberculin protein derivative). If someone has been exposed to tuberculosis, the immune system will cause a rash-like reaction on the skin. But more diagnostic tests will need to be performed to be sure that someone has TB.6

So when the telltale red bumps appeared on her arm, Natalie did not immediately worry about having the disease. She took the 17-hour train ride back to the medical center for additional tests. Clinicians used several techniques to diagnose Natalie such as looking at her mucous under a microscope (in what’s called sputum smear microscopy) and taking an x-ray that revealed a growth in her lungs.

Natalie was diagnosed with active pulmonary – lung-based – tuberculosis. She returned to the United States for care, but Natalie’s disease status meant that she couldn’t interact normally with her friends and family. She had to wear a mask, even while spending time with her loved ones, so they wouldn’t become sick.

Natalie decided to go to a research facility that was a former sanatorium while she needed care. When she arrived, she was the only tuberculosis patient. The disease caused Natalie to lose weight, which is normal for people with TB. She also lost part of her lung. Natalie not only grappled with her physical health, but also her emotional health. She ended her Peace Corps position early, separated from her social support, and coped with the severity of the disease.5

The past maladies still linger

Natalie isn’t alone. It is estimated that one-third of the world is infected with tuberculosis.7 Tuberculosis is caused by a bacterium called Mycobacterium tuberculosis. It is an airborne pathogen, meaning that the germs can be released into the air when someone who has the active pulmonary disease coughs, sneezes, or sings. Conditions have to be right for those bacteria to reach another person such as a close space and prolonged contact.6 For thousands of years tuberculosis bacteria have been quite successful in using this method of transmission. Why isn’t everyone stuck in isolated sanatorium facilities or, at least, wearing a mask in public?

Being infected is not the same thing as having the active tuberculosis disease. There are three possible outcomes when you are exposed to tuberculosis bacteria: 1) usually your immune system fights them off and gains “memory” of how to fight them again, 2) the bacteria win against your immune system and take hold with the active disease, or 3) you can have latent tuberculosis infection where the symptoms may appear later in life.6 This third possibility is one of the most worrisome aspects of tuberculosis.

Latent TB infection is possible because there are cells in the body that can contain and destroy threats like tuberculosis bacteria. Sometimes the immune system keeps TB at bay, while other times the bacteria can escape and start to multiply. Imagine that your immune system is like the Pac-Man character who has the ability to eat the ghosts in the game. Pac-Man can chase, corner, and destroy his enemy. But if something goes wrong, the cornered ghosts can eventually manage to sneak by the yellow protagonist—then the issue of latent TB infection arises.


Fig. 2: Colored microscopic image of M. tuberculosis bacteria.


While latent TB infection is not contagious, it can become the active disease under a number of circumstances if the immune system fails. For instance, if someone has HIV/AIDS and their immune system is compromised, the tuberculosis-causing bacteria can more easily thwart the body’s defense mechanisms. For this reason, latent TB infection is treated the same way as the active disease by using antibiotics.6

Without treatment, one in ten people with healthy immune systems who are infected will develop the active, and contagious, tuberculosis disease.6 Despite being preventable and treatable, TB is still one of the top ten causes of death in the world. The World Health Organization estimated that in 2015 alone the disease killed 1.8 million people and 10.4 million new TB cases emerged.1

Despite popular belief, tuberculosis is even present in the United States, and it isn’t going away without a fight. California actually saw an increase in the number of people with the active tuberculosis disease in 2015; the state was responsible for 20% of the cases in the U.S. Over 2.3 million – or 6% of – California residents have latent TB infection.8

Santa Clara County (home to Stanford University) has a tuberculosis rate that is three times the national average.9,10 Tuberculosis takes advantage of the interconnected global society that we live in. Two risk factors of latent TB infection in the U.S. include being born in a foreign country or traveling abroad to regions with higher TB rates. It can be hard to predict when the numbers will increase because latent TB infection does not become contagious at a specific time after being exposed.6 TB cases in Santa Clara County have not always decreased over the last few years.10 In 2016, the county had 160 cases of the active disease and over 160,000 people with latent TB infection.11

Recently, there have been tuberculosis scares at the Palo Alto Veteran’s Affairs Hospital and the Santa Clara Valley Medical Center. These two cases involved only a single infected employee in each of the buildings, but they prompted tuberculosis screening of hundreds of veterans that received care as well as preemptive treatment of hundreds of newborn babies, respectively.12–14

While it was unlikely that the babies would develop tuberculosis due to their limited exposure to the sick nursery employee, they were still given daily antibiotic treatments because of the severity of the disease.12,13 The Centers for Disease Control and Prevention remind us, “Every TB case is a potential outbreak.”6

Usually TB disease and latent TB infection can be treated in six to nine months when medications are taken properly and patients have support. However, the problem has worsened as tuberculosis bacteria have become resistant to some antibiotics. If the disease is a drug-resistant form, patients need stronger medications and longer treatment times. Nearly half a million people worldwide have drug-resistant TB,1 but that number is much smaller in California (23 cases).8

The state notes that drug-resistant TB cases can be difficult and resource-intensive to treat.8 Natalie had an extreme type of drug-resistant TB (XDR TB) that is a rarity in the United States. Writing about her tuberculosis experience, she explains that “a standard case can be cured for less than $100…my treatment costs taxpayers seven figures and lasted well over two years.”5 It could be quite costly if drug-resistant TB cases start increasing.

Natalie had to rely on harsher therapies that had severe side effects like nausea, loss of feeling in her feet, and loss of some hearing ability. She couldn’t work during her long treatment because she was both contagious and in poor health. If she had been treated elsewhere in the world, Natalie might have also faced discrimination for having the disease itself.5

What can the Bay Area do?

When you don’t know someone with TB, there is a temptation to ignore this public health threat. However, it makes more sense to take preventive measures before tuberculosis, including a drug-resistant strain, spreads further. These efforts could save money, time, and lives.

The Centers for Disease Control and Prevention renewed a large effort in the 1990’s to eliminate TB in the United States. Once funds and resources were allocated to this goal both on the national level and in the San Francisco Bay Area, the number of TB cases started to decline.6 On the other hand, reducing funding can increase rates of tuberculosis.15

An estimated 8.5% of Santa Clara County residents have latent TB infection, but many don’t know that they have it.11 Common tuberculosis disease symptoms are mild and can be mistakenly brushed off such as a persistent cough, chest pain, and unexplained weight loss.5,6 TB can affect anyone regardless of their age, race, sex, or socioeconomic status.

Dr. Tara Perti at the Santa Clara County Public Health Department adds that the county assigns a Public Health Nurse to every TB patient during treatment. Their role is to provide support and ensure treatment completion in collaboration with the patient’s medical provider. Many medical facilities in the region can screen for active tuberculosis and latent TB infection.11 Ultimately, though, these services are only effective if Bay Area residents are aware of their risk of tuberculosis.

A critical part of destigmatizing tuberculosis is being informed about its presence in the United States today. Tuberculosis patient numbers are important to capture in statistics and regional reports, but their stories also survive in blogs (such as http://www.tbphotovoice.org). Natalie Shure’s two-year tuberculosis battle is a concern as drug-resistant bacteria emerge globally. She was one of the fortunate TB patients with access to health care who was able to be cured.5

Another U.S. resident who acquired latent TB infection after traveling abroad said, “TB is just a disease like any other. The one good thing about it is it is treatable.”16 There is still a long way to go in addressing tuberculosis, even in the modern San Francisco Bay Area. Fortunately, we have access to innovative people and resources to combat the disease.



  1. World Health Organization. Global Tuberculosis Report 2016. WHO Press; 2016. http://apps.who.int/iris/bitstream/10665/250441/1/9789241565394-eng.pdf?ua=1.
  2. McMillen CW. Discovering Tuberculosis: A Global History, 1900 to the Present. New Haven: Yale University Press; 2015.
  3. Robert Koch and Tuberculosis. Nobel Media AB. https://www.nobelprize.org/educational/medicine/tuberculosis/readmore.html. Accessed February 1, 2017.
  4. Rothman SM. Living in the Shadow of Death: Tuberculosis and the Social Experience of Illness in American History. Baltimore: The Johns Hopkins University Press; 1995.
  5. Shure N. Inconspicuous Consumption. Buzzfeed. 2014. https://www.buzzfeed.com/natalieshure/you-never-think-about-tuberculosis-until-you-lose-two-years?utm_term=.jckQl5qJp#.qkljDkyqd.
  6. Centers for Disease Control and Prevention. Introduction to the Core Curriculum on Tuberculosis: What the Clinician Should Know. 6th ed.; 2013. doi:10.1128/IAI.00057-06.
  7. Tuberculosis. World Health Organization. http://www.who.int/mediacentre/factsheets/fs104/en/. Published 2017. Accessed February 1, 2017.
  8. California Department of Public Health. Report on Tuberculosis in California, 2015.; 2016. http://www.cdph.ca.gov/programs/tb/Documents/TBCB_Report_2015.pdf.
  9. Carbajal M. Santa Clara County TB Rates Remain Higher than Twice the National Average.; 2015.
  10. Santa Clara County Public Health Department. Tuberculosis in Santa Clara County: A Summary.; 2016. https://www.sccgov.org/sites/sccphd/en-us/Residents/TbResources/Documents/scctb-factsheet.pdf.
  11. Perti, T. (2017, March 14). Santa Clara County TB Prevention Update [Email correspondence].
  12. Seipel T. San Jose tuberculosis exposure: Babies born at Valley Med start long drug regimen. The Mercury News. http://www.mercurynews.com/2015/12/20/san-jose-tuberculosis-exposure-babies-born-at-valley-med-start-long-drug-regimen/. Published December 20, 2015.
  13. Alexiou J. Tuberculosis Exposure Detected.; 2015. https://www.scvmc.org/newsroom/Pages/Tuberculosis-Exposure-Detected.aspx.
  14. NBC Bay Area Staff. Potential Tuberculosis Exposure at VA Hospital in Palo Alto. NBC. http://www.nbcbayarea.com/news/local/Potential-Tuberculosis-Exposure-at-VA-Hospital-in-Palo-Alto-369489512.html. Published February 20, 2016.
  15. Higashi J. Report on Tuberculosis in San Francisco: 2012.; 2013.
  16. William. Lynnette’s Story From Snohomish County, Washington, U.S.A. TB Photovoice. http://tbphotovoice.org/stories/lynnette/.

Cover image courtesy of Jeramiah Winston.

Fig. 1: “Mycobacterium tuberculosis Bacteria, the Cause of TB” by the NIAID is licensed under CC BY 2.0

Fig. 2: “6806” by Greg Knobloch is courtesy of the Public Health Image Library