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Tuberculosis Is The World's Top Infectious Killer. Aid Groups Say Trump's Funding Freezes Will Cause More Deaths

CNN  — 

When health workers stopped visiting her home in Pakistan to administer tuberculosis medication, Ratna Jamni began dragging herself to a clinic "step by painful step, when even standing feels impossible."

The 40-year-old had been receiving treatment and mental health support for months at home after contracting drug-resistant TB, but those visits have all stopped.

"Every trip is painful, exhausting and humiliating. I don't know how much longer I can do this," she told CNN via the Dopasi Foundation, a Pakistan-based NGO whose USAID-funded programs helped provide her health care.

"The journey is long, my body is weak, and every breath feels heavier than the last. I wonder if it's even worth it. I wish this suffering would end – either the help returns or I no longer have to endure this pain."

Tuberculosis, a bacterial infection usually found in the lungs, remains the world's top infectious killer, causing 1.25 million deaths worldwide in 2023, according to the World Health Organization (WHO).

With the right health care and drugs, TB is treatable and preventable. Without treatment, it has a death rate of close to 50%.

Like that of millions of other TB patients across the world, Jamni's treatment was supported by the United States Agency for International Development (USAID). It has now been interrupted by the Trump administration's sudden freezing, and subsequent cutting, of vast swathes of the agency's funding.

Aid groups and doctors warn that these cuts are likely to cause thousands of unnecessary deaths and a rise in TB infections worldwide, including in the US itself; and create the conditions for an extremely drug-resistant form of the disease to spread.

Already, more than 11,000 additional TB patients are estimated to have died in the two months since almost all USAID funding froze on January 24, according to a model built by UN-affiliated organization Stop TB Partnership.

TB infections are also expected to increase by 28-32% globally this year as a result of the cuts, according to a memo issued by a top USAID official, Nicholas Enrich, who was placed on administrative leave.

The State Department, which now handles queries for USAID, told CNN that certain TB programs are "active today in more than a dozen countries," in line "with Secretary (of State Marco) Rubio's exemption for life-saving humanitarian assistance."

"These programs are helping to find and cure hundreds of thousands of cases of tuberculosis by providing access to low-cost, life-saving testing and medicine."

US funding was an integral part of the global TB response, distributing grants both directly to 24 national governments whose countries have high rates of the disease and via international or local non-governmental organizations.

USAID was deeply enmeshed in global HIV/AIDS health care too, and TB is the leading cause of death for people with HIV, according to WHO.

Unlike previous changes in funding flows, which came with prior warning, this freeze is unprecedented in both its scale and abruptness, meaning that it's "very difficult for these countries overnight to find the resources" to plug the gap, Dr. Lucica Ditiu, CEO of the UN-affiliated Stop TB Partnership, told CNN.

And while local aid groups call for a shift to domestic funding, the situation right now is deteriorating.

For the 27 countries worst affected by the cuts, that funding gap is leading to "crippling breakdowns in their TB response with devastating consequences," WHO said in a statement on March 20.

The precise nature of the impact has varied worldwide, depending on the role USAID played in the network of funding streams contributing to each country's TB program.

In almost half of Mozambique, for example, no one can currently be diagnosed with TB, since US funding supported its lab networks and system that transported samples of spit and mucus, Ditiu said. Some programs, like Stop TB Partnership's Global Drug Facility, which facilitates global access to relatively cheap drugs, have had some funding restored by temporary waivers, Ditiu said.

But more have not, and nine countries are struggling to procure TB drugs, threatening patients' access to them, WHO said.

Health workers based in Cambodia, Pakistan, Nigeria, South Africa and Eswatini told CNN the biggest cuts to their programs were mostly in active case-finding, which allows for earlier diagnosis to stem the spread of disease, and in community outreach.

One such USAID-funded program in Cambodia, run by local HIV and TB organization KHANA, had screened more than 780,000 people for TB in remote areas, traced more than 16,000 close contacts of TB patients and supported more than 800 patients with multi-drug-resistant TB during the past five years, according to its executive director, Choub Sok Chamreun.

All that work has now stopped. As a result, the number of new TB cases reported in the region has dropped from about 650-850 per month to just 250 in February, meaning that hundreds are going undiagnosed and without care, Chamreun told CNN.

"This means that people don't come to services. It means that the infection continues to spread over the community … it means that the aim to end TB by 2030 is impossible," he said, referencing the UN's goal to largely eliminate the disease by the end of the decade.

Similarly, another case-finding program supported by USAID in 27 of Pakistan's districts has ceased, along with the means of transporting sputum samples, and community monitoring that aims to identify any barriers to TB treatment, Kinz ul Eman, CEO of the Dopasi Foundation, told CNN.

Sudden cuts also mean immediately laying off field health workers who "actually risked their life to support your project activity, to support their community," she added.

TB disproportionately affects marginalised communities and people living in poverty for whom government health care is less accessible, making such outreach even more important.

One such program, overseen by Dr. Steven John, an official at the Ministry of Health in Adamawa State, Nigeria, was implementing TB health care for nomadic populations there.

With the funding freeze, his program can no longer reach the 60-70% of the community who have yet to access its services, even as people there "approach the organization (saying) 'When are you coming?'" he told CNN.

Suddenly restricting access to drugs and treatment also creates the conditions for a mutated, multi-drug-resistant strain of TB to thrive as patients partway through a four- or six-month treatment regimen may be forced to stop taking them, aid groups and doctors say.

"Anytime you cease a treatment in the middle of the course of therapy, you promote the selection of drug resistance and people then become contagious again to others in their community," explained Dr. Kenneth Castro, a professor at Emory University who previously served as director of the division for tuberculosis elimination at the US Centers for Disease Control and Prevention (CDC).

Very few drugs can treat such an extreme form of TB. "You create, basically, a bug which is virtually resistant to what we have," said Ditiu.

That risk is magnified since a lot of USAID's funding, especially in Africa, focused on supporting people living with multi-drug-resistant TB, she added.

And anecdotal reports of patients stopping their courses of medication are already emerging. One patient in Uganda started sharing her medication with her husband, meaning they are both taking half the prescribed amount, Bruce Tushabe, an official at advocacy group the AIDS and Rights Alliance for Southern Africa, told CNN.

Another person who used to get medication from a specialist, now-closed clinic can't stand in the queues at the general clinics due to the stigma TB patients still face, Tushabe added.

As TB rates rise globally, they are likely to increase in the US as well, said Castro, while pointing out that the country still has one of the world's lowest rates of the disease at 2.9 cases per 100,000 people.

Nonetheless, warning signs are lighting up – in January, the Kansas City metro area was hit by a wave of TB, causing dozens of illnesses and at least two deaths. And childhood TB cases in Europe rose by 10% in 2023, showing that transmission of the disease is still ongoing, WHO said on Monday.

"The irony," Castro added, "is that these disinvestments end up resulting at higher cost to recover and mitigate the damage done."

Danger Zones Where Tuberculosis Spreads Most Easily

Comprehensive guide to the primary transmission routes of tuberculosis and effective prevention measures

Tuberculosis (TB) remains one of the world's deadliest infectious diseases, affecting millions annually despite being preventable and curable. Understanding how TB spreads is crucial for both prevention efforts and identifying those at highest risk. This article examines the transmission mechanisms of tuberculosis and provides evidence-based prevention strategies.

The airborne nature of tuberculosis transmission

Tuberculosis is primarily transmitted through the air when people with active pulmonary or laryngeal TB cough, speak, sing, sneeze, or otherwise expel tiny droplets containing Mycobacterium tuberculosis bacteria. These microscopic droplet nuclei can remain suspended in the air for hours, especially in enclosed spaces with poor ventilation.

Unlike many other infectious diseases, TB isn't typically spread through casual physical contact like handshakes or hugs, sharing food, drinks, or utensils, touching surfaces or objects used by someone with TB, sexual contact, or blood transmission.

This airborne transmission route makes TB distinctly different from other common infections and explains why certain environments and situations create higher risk scenarios for transmission.

Factors that increase transmission risk

While anyone can potentially contract tuberculosis through airborne exposure, several key factors significantly increase transmission probability:

Proximity and duration of exposure: Close, prolonged contact with someone who has untreated active TB disease dramatically increases risk. Household members of TB patients have approximately 15% risk of developing active TB themselves.

Enclosed, poorly ventilated spaces: The bacteria concentrate in confined areas with limited air exchange. Research shows that improving ventilation can reduce transmission risk by 70-80%.

Bacterial load of the infected person: Individuals with cavitary lesions in their lungs or positive sputum smears typically release more bacteria when coughing, making them more infectious.

Absence of treatment: People with active TB who haven't started appropriate antibiotic therapy remain highly contagious. After approximately two weeks of proper treatment, most patients' infectiousness decreases significantly.

Immunocompromised status of exposed individuals: Those with weakened immune systems, particularly HIV-positive individuals, face substantially higher risks both of becoming infected after exposure and of developing active disease if infected.

High-risk settings for tuberculosis transmission

Certain environments create particularly favorable conditions for TB transmission due to their combination of crowding, poor ventilation, and concentration of vulnerable individuals:

Healthcare facilities: TB transmission in hospitals and clinics occurs primarily when patients with undiagnosed TB are not properly isolated. Healthcare workers have 2-3 times higher TB rates than the general population in many regions.

Correctional facilities: Prison populations worldwide experience TB rates 10-100 times higher than general populations due to overcrowding, inadequate ventilation, and higher rates of risk factors.

Homeless shelters: Studies show TB outbreaks occur frequently in shelters, with transmission facilitated by overcrowding, transient populations, and limited healthcare access.

Long-term care facilities: Nursing homes and other residential facilities can experience rapid TB spread due to the concentration of older adults with weakened immunity in close quarters.

Refugee camps and immigration centers: Overcrowding combined with populations from high-burden TB countries creates transmission hotspots.

Congregate settings in high-burden regions: Schools, workplaces, and public transportation in countries with high TB prevalence can serve as transmission sites, especially when TB screening is inadequate.

Special transmission considerations

Several TB transmission scenarios deserve special attention:

Extrapulmonary TB: Most forms of extrapulmonary tuberculosis (affecting areas outside the lungs) are minimally contagious or non-contagious. The exception is laryngeal TB, which can be highly infectious.

Children with TB: Young children with primary TB disease rarely transmit the infection because they typically have fewer bacteria in their lungs, produce weaker coughs, and often have non-cavitary disease.

Silent transmission: Research increasingly shows that TB can spread through normal breathing and speaking, not just coughing, contributing to what epidemiologists call "silent transmission" from people with minimal symptoms.

MDR/XDR TB: Multi-drug resistant and extensively drug-resistant tuberculosis strains transmit through the same mechanisms as drug-susceptible TB but present greater public health concerns due to treatment challenges.

Prevention strategies for tuberculosis transmission

Preventing TB transmission requires multi-level approaches:

Rapid identification and treatment: Finding and properly treating active TB cases remains the cornerstone of prevention. Studies show each untreated TB patient may infect 10-15 others annually.

Airborne infection control measures: Proper ventilation (natural or mechanical), HEPA filtration systems in high-risk settings, ultraviolet germicidal irradiation (UVGI) in appropriate facilities, and proper patient isolation in healthcare settings all contribute to reducing airborne transmission.

Personal protective equipment: N95 respirators (not regular surgical masks) can protect healthcare workers and visitors when worn properly around infectious TB patients.

Preventive treatment: Treating latent TB infection with isoniazid, rifampin, or newer shorter regimens reduces the risk of developing active disease by 60-90%.

BCG vaccination: Though imperfect, the Bacille Calmette-Guérin vaccine offers partial protection, particularly against severe forms of TB in children.

Cough hygiene education: Teaching TB patients to cover coughs with tissues or elbows and proper disposal of potentially contaminated materials reduces transmission risk.

Addressing systemic factors: Reducing overcrowding, improving nutrition, treating HIV, and addressing other social determinants significantly impacts TB transmission.

What to do if exposed to tuberculosis

For those who have been exposed to someone with infectious TB, consult with healthcare providers about TB testing (either skin test or blood test). If recently infected, discuss preventive treatment options. Monitor for TB symptoms, including persistent cough, night sweats, weight loss, and fatigue. Understand that most healthy adults who become infected with TB bacteria initially develop latent TB infection, where the bacteria remain inactive and non-contagious.

The role of public health programs

Public health departments play crucial roles in breaking TB transmission chains through contact investigation to identify and test people exposed to TB, Directly Observed Therapy (DOT) to ensure treatment completion, TB screening programs for high-risk populations, education and awareness campaigns, and outbreak investigation and management.

Global challenges in TB transmission control

Despite decades of efforts, TB transmission continues globally due to delayed diagnosis, particularly in resource-limited settings, incomplete treatment leading to continued transmission and drug resistance, HIV co-infection facilitating both TB transmission and progression, limited healthcare infrastructure in high-burden regions, and socioeconomic factors including poverty, malnutrition, and overcrowded housing.

Understanding the science behind tuberculosis transmission underscores the importance of comprehensive public health approaches. While TB remains a serious global health threat, its airborne transmission route is well understood, and effective prevention measures exist. Continued investment in TB control programs, research, and addressing underlying social determinants remains essential to reducing the global burden of this preventable disease.

Yakima Area Health Officials Working Together To Address Tuberculosis Cases

Indian Health Services, Yakama Tribal Health and the Yakima Health District are collaborating to address the increase in tuberculosis cases in the Lower Yakima Valley, including areas within the Yakama Reservation. 

The work includes identifying potential exposures, notifying and testing anyone who may have been in close contact with someone diagnosed with active TB, according to a news release from Katherine Saluskin, the Yakama Nation tribal health officer deputy director.

Those identified will be contacted by Indian Health Services or the county health district for testing and further evaluation.

As of Wednesday, Yakima County has 17 cases of tuberculosis, Stephanie Ruiz, the health district spokesperson, said in an email. The county health district reported earlier that 16 people are sick with tuberculosis in the Lower Yakima Valley. The first case in the county was confirmed in September, but not all active cases are linked to the same outbreak.

Public health officials are working to ensure individuals receive timely and appropriate treatment to protect themselves and others, the release said. 

The county health district has been in touch with local health care providers to ensure they are aware of the situation and consider TB as part of their differential diagnosis when evaluating patients, Ruiz said.

"Additionally, YHD is actively testing individuals who have been identified as close contacts to confirmed TB cases to prevent further spread," she added.

Tuberculosis, or TB, is a respiratory disease caused by a bacteria and spread through the air when an infected person coughs, sneezes or speaks, according to the CDC. Without treatment, it can be fatal. Some people can have the disease without symptoms, called inactive TB.

Symptoms of active TB include:

• Persistent cough lasting more than three weeks;

• Coughing up blood or phlegm;

• Chest pain;

• Unexplained weight loss;

• Night sweats;

• Fever and chills; and

• Fatigue and weakness.

The risk of exposure is low unless you have prolonged exposure to an infected person, local health officials said.

Anyone with concerns should contact their primary care provider. Treatment can take months, but most people can receive their treatment at home, county health officials have said.

Is vaccine for tuberculosis available?

Bacille Calmette-Guérin is a vaccine for tuberculosis, but the vaccine is not generally used in the United States, according to the U.S. Centers for Disease Control and Prevention.

Many people born outside the U.S. Have been vaccinated with BCG, which is given to infants and small children in countries where the disease is common.

The vaccine protects children from getting severe forms of active TB disease, such as TB meningitis. Its protection weakens over time, the CDC said.

Those who have received the TB vaccine should tell their health providers, especially if they're getting tested for TB infection. The vaccine can cause a false positive TB skin test reaction.

Source: Centers for Disease Control

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