Coordinated responses to maintain tuberculosis care amid climate emergencies: challenges and perspectives based on the events of Brazil

INTRODUCTION

The Unified Health System (Sistema Único de Saúde, SUS) is one of Brazil’s major public health achievements, providing universal, comprehensive and free healthcare since 1990.1 Created in response to civil society demands, SUS is recognised globally for its success, particularly by promoting coordinated and integrated responses in primary, secondary and tertiary care among the three levels of management—federal, state and municipal.2

SUS has been vital in crises like the COVID-19 pandemic, ensuring hospital bed availability, care resources, field hospitals and units for managing mild COVID-19 cases; it also played a key role in acquiring and distributing vaccines against the virus.3 These coordinated efforts demonstrate SUS’ resilience and efficiency in maintaining public health during emergencies, highlighting its crucial role in crisis response.

In the wake of crisis, climate change increasingly affects global health, requiring swift, coordinated actions to prevent overburdening health systems and protect vulnerable populations, especially in tuberculosis (TB) control.4 SUS, with its broad reach and capacity for organised response, is crucial in addressing these challenges. Its resource mobilisation and comprehensive care make it essential in adapting to health risks posed by climate change.5

Beyond its role in crisis management, SUS exemplifies the importance of public health systems in fostering equity and accessibility, even amid socioeconomic disparities. By integrating technological advances and prioritising decentralised care, SUS has maintained its capacity to address health challenges. This demonstrates the system’s adaptability, which will be critical as climate change continues to redefine public health priorities and amplify existing vulnerabilities.

The objective of this study is to analyse coordinated responses to sustain TB care during climate-related emergencies, with a focus on the 2024 flooding in Rio Grande do Sul, Brazil. Drawing on field experiences and programme data, it highlights context-specific actions that supported continuity of care amid disaster, aiming to provide practical lessons for policymakers and health practitioners facing similar crises globally.

The emergence of climate change and its potential effects on public health

Climate change is an escalating threat to global health, driven by long-term shifts in temperature and climate patterns, influenced by natural factors and human-induced greenhouse gas emissions.6 The World Health Organization (WHO) estimates that climate change could cause around 250 000 additional deaths annually between 2030 and 2050 due to malnutrition, malaria, diarrhoea and heat stress, intensifying vulnerabilities in affected populations.7

The intensification of climatic events—floods, droughts and heatwaves—is strongly associated with the rise in transmissible diseases and the worsening of pre-existing conditions.8 It also affects social determinants of health, increasing barriers to essential resources like clean water, food security, housing and sanitation. These impacts exacerbate inequities, particularly for vulnerable populations, making it more challenging to meet public health needs.9

Most systematic reviews suggest that climate change worsens human health.10 This exacerbation of vulnerabilities, such as increased poverty, migratory movements and food insecurity, significantly impacts health conditions.10 11 TB, in particular, deserves attention, as its risk factors can have short, medium and long-term effects on operational and epidemiological indicators, further complicating public health efforts in the face of climate change.

Brazil is particularly vulnerable to climate change due to its size and socioeconomic inequalities.12 The increasing frequency of floods and droughts has already challenged its healthcare system. These adverse conditions disproportionately affect poorer populations, deepening social inequalities. As a result, Brazil’s ability to respond to public health crises caused by climate-related events is further strained, exacerbating existing vulnerabilities.12

Global climate agreements, like the Paris Agreement, aim to reduce greenhouse gas emissions and tackle climate change impacts.13 The agreement mandates developed nations to invest $100 billion annually in climate mitigation and adaptation for developing countries. Its goal is to limit global temperature increases to below 2.0°C above preindustrial levels, with efforts to keep the rise to 1.5°C, ensuring a unified response to the climate crisis.13

In Brazil, the goal is to reduce greenhouse gas emissions by 37% below 2005 levels by 2025, and by 43% by 2030.13 However, achieving these targets requires broad societal engagement.14 Beyond environmental policies, the impacts of climate crises demand adaptation to new health challenges. It is essential to integrate public health measures to ensure the resilience of health systems in the face of these changes.

The impacts of climate change extend beyond immediate health crises, influencing long-term patterns of morbidity and mortality. For example, rising temperatures can expand the geographical range of vector-borne diseases, placing additional strain on health systems in vulnerable regions. Strategic investments in climate-resilient infrastructure are essential to mitigate these risks, ensuring that public health systems remain robust and responsive.15 16

The TB situation in Brazil and the impacts of climate changes

TB is one of the most prevalent infectious diseases in Brazil, and climate change has worsened the challenges in controlling it. TB disproportionately affects vulnerable populations, who are also more impacted by climate events. In 2023, Brazil reported 80 012 new TB cases, with an incidence rate of 37.0/100 000. Eleven states exceeded the national average, including Roraima (85.7/100 000), Amazonas (81.6/100 000) and Rio de Janeiro (70.7/100 000).17

Rio Grande do Sul reported an incidence of 40.0/100 000 in 2023, with 4 584 new cases, representing 52.4% of cases in southern Brazil.17 The state’s floods severely disrupted health services, creating major challenges in TB control. Many municipalities had to suspend diagnostic testing and treatment, which may lead to higher rates of treatment loss to follow-up and increased TB-related mortality, worsening the public health impact in the coming years.

The current stage of the HIV epidemic in Brazil shows stabilisation, according to official Ministry of Health data, though there is a warn of a potential reemergence. A trend analysis of HIV cases from 2005 to 2020 revealed an annual decrease of −4.40% (95% confidence interval, 95% CI −5.80 to −2.90). The southern region showed a decline of −3.00% (95% CI −4.70 to −1.20), but Rio Grande do Sul continues to report high rates, exceeding 31.51/10 000.18

A time-series study using data from 2001 to 2022 revealed an annual percentage decline of −0.97% (95% CI −1.23 to −0.74) in pulmonary TB cure rates, −1.11% (95% CI −1.42 to −0.85) for TB-HIV coinfected individuals, and −1.44% (95% CI −1.62 to −1.31) for TB retreatment cases in Brazil.19 Rio Grande do Sul showed similar trends: −1.75% (95% CI −1.99 to −1.56), –1.99% (95% CI −2.25 to −1.79), and −2.70% (95% CI −2.98 to −2.42), respectively.19

The challenges for TB control in Rio Grande do Sul were worsened by the April 2024 climate emergency. The destruction of laboratories and health centres interrupted rapid diagnostic testing, such as GeneXpert. Additionally, the loss of TB medications in Porto Alegre deepened the crisis. A rapid, coordinated response became essential to restore services and ensure treatment continuity, safeguarding the population from further public health impacts.

The climate scenario in Rio Grande do Sul: floods and health repercussions

Rio Grande do Sul has faced severe climate change effects, notably from an extreme rainfall and flooding. These events were influenced by a combination of climatic factors, including the interaction of tropical and polar air masses and the effects of El Niño.20 The continuous rainfall over several days caused significant weather disruptions, underscoring the growing impact of climate change on the region and its infrastructure challenges.20

The state experienced one of its worst floods, with heavy rains starting on 27 April. Within 2 weeks, the state faced extreme flood risks on the hydrological scale. During this time, the SUS National Force—a programme focused on prevention, assistance and response to situations, disasters and care disruptions—was deployed to support the emergency response, including on-site actions in affected municipalities to mitigate the disaster’s impact.16

On 4 May, the Brazilian Ministry of Health established the Emergency Operations Center (EOC), overseen by the Department of Public Health Emergencies of the Secretariat for Health and Environment Surveillance. The EOC focused on managing the coordinated health response to the intense rains and floods in the southern region, addressing public health emergencies caused by heavy rainfall, floods and related disasters at a national level.21

The magnitude of the 2024 floods in Rio Grande do Sul far surpassed the 1941 flood, highlighting the increasing impact of climate change on the weather patterns.22 State data show that 96% of municipalities (479/497) were affected, with over 2.4 million people impacted. The floods caused more than 180 deaths and left approximately 160 000 individuals displaced or homeless, making it one of the most devastating climate-related disasters in history.20

The floods severely damaged Rio Grande do Sul’s health infrastructure, with many health centres destroyed and critical supplies lost. Porto Alegre, the state capital, lost all medications, including those for TB treatment, forcing the government to quickly redistribute supplies to maintain treatment continuity. This disruption of healthcare services created significant challenges, especially in controlling infectious diseases like TB during the emergency response.

Rio Grande do Sul’s experience underscores the urgency of integrating climate adaptation measures into urban planning. Improved infrastructure, such as flood-resistant health facilities, and pre-emptive resource allocation for disaster-prone areas could mitigate the impact of extreme weather events. Collaborative planning will be critical in addressing both immediate needs and the broader consequences of climate-induced disasters on public health.23

Coordinated responses to climate emergencies: strategies for the continuity of care

Rio Grande do Sul faced a critical situation, underscoring the urgent need to reorganise TB surveillance, diagnosis and treatment (figure 1). The General Coordination of Tuberculosis, Endemic Mycoses and Nontuberculous Mycobacteria Surveillance (CGTM), under the Department of HIV/AIDS, Tuberculosis, Viral Hepatitis and Sexually Transmitted Infections, supported these efforts in a coordinated manner with the municipality and state.

TB diagnosis and treatment occur in all primary healthcare services, so unit closures due to flooding impacted continuity of care. In Porto Alegre, 21 of 134 health units closed: 14 from flooding and 7 due to power or water supply issues, area flooding or staff shortages. The response was immediate, with aeromedical evacuations, emergency care, field hospitals in strategic locations and mobile health units near shelters ensuring ongoing care.

Additionally, civil society played an essential role—its guaranteed space within SUS has promoted the democratisation and strengthening of public health. Direct communication between local representatives and municipal, state and national managers was key to understanding the population’s needs. This coordination offered support to local areas through peer guidance, enhancing communication between management and the population.

Given the situation, beyond the actions taken by state and municipalities, the CGTM implemented measures to mitigate the impact of the floods on TB. Technical Note No. 015/2024-CGTM provided guidelines for maintaining TB diagnosis, treatment and surveillance in the state.24 Key measures included prevention efforts in shelters, the use of digital technologies for continuous treatment and dispensing medications for extended periods, among others.

Rio Grande do Sul has 24 GeneXpert machines across 17 municipalities.25 In cities like Pelotas and São Leopoldo, their use was temporarily halted due to flooding risks. However, a rapid response coordinated by municipal, state and national TB programmes involved relocating equipment and contracting private laboratories to perform sputum smear microscopy and culture testing. These actions were crucial in ensuring the continuation of TB diagnosis.

Additionally, health teams were mobilised to isolated areas to ensure that vulnerable populations continued to have access to TB treatment. Social protection measures, including shelter and food for displaced individuals, were implemented to promote treatment adherence and prevent loss to follow-up. These efforts highlight SUS’ ability to respond to crises, efficiently deploying resources and healthcare professionals to maintain the care.

Recommendations for addressing climate emergencies in TB management

Municipalities must prioritise the development of contingency plans tailored to local vulnerabilities. These plans should establish clear protocols for maintaining diagnostic services, including alternative sites for testing, mobile health units and partnerships with private laboratories to ensure uninterrupted access to TB diagnosis during emergencies. Strengthening local infrastructure to withstand climate impacts is also crucial for service continuity.

States should implement integrated response strategies that coordinate efforts among municipalities to optimise resource allocation. This includes the establishment of regional health task forces to rapidly mobilise human and material resources during disasters. Prepositioning essential supplies like TB medications in climate-resilient facilities can prevent shortages, while fostering intermunicipal collaboration ensures equitable access to care across affected regions.

At the national level, governments must institutionalise disaster preparedness within public health systems. National contingency plans should include robust mechanisms for resource redistribution, such as emergency supply chains and aeromedical evacuation capabilities. Regular simulations and training for health professionals should be conducted to enhance readiness, ensuring the health workforce is equipped to respond effectively during crises.

Cross-sector collaboration is essential to integrate public health into broader disaster risk reduction policies. This includes partnerships with environmental, transportation and housing sectors to address the social determinants exacerbated by climate change. For example, ensuring access to safe shelters and food security can reduce TB risk factors like malnutrition and overcrowding during emergencies, mitigating the disease’s spread.

Finally, leveraging digital health technologies can bolster TB management in disaster scenarios. Electronic health records and telemedicine platforms enable real-time monitoring of patient progress and remote consultations, minimising disruptions. Investing in these technologies, along with community-based approaches to disseminate information and ensure treatment adherence, enhances the resilience of health systems and safeguards TB care in future emergencies.

The need for a TB vaccine in the context of extreme climate events

Brazil has one of the largest public vaccination programmes in the world—the National Immunization Program (Programa Nacional de Imunização, PNI). It enables agile and organised distribution of vaccines and supplies during health crises.26 In extreme events, such as emerging vaccine-preventable diseases, the PNI has been a leader in the Americas, efficiently distributing vaccines and supplies, focusing on mitigating immediate impacts on public health.

The need for an effective TB vaccine becomes even more urgent in the context of extreme climate events. Malnutrition, lack of adequate shelter, and overcrowding in temporary shelters are known risk factors for the development and spread of TB.27 28 Additionally, stress on health services can lead to failures in diagnosis and continuity of treatment, increasing the possibility of outbreaks and the emergence of drug-resistant strains.

In this context, an effective TB vaccine would be a vital tool for mass prevention, significantly reducing the incidence of the disease and its devastating impact on vulnerable populations, particularly during environmental and climate-related crises. Implementing vaccination strategies in high-risk areas, combined with broader climate adaptation measures, would be crucial in mitigating the adverse effects of climate changes on public health.

It is necessary to strengthen research focused on developing an effective vaccine. It is clear that Brazil’s exemplary response, through its PNI, could be enhanced in extreme scenarios. The rapid implementation of a TB vaccine, once experimental trials are completed, would not only enable a qualified response to TB as a public health issue by 2030 but also support emergency responses in health crises arising from climate change.

Final considerations

Climate change directly affects TB control by exacerbating social vulnerabilities and disrupting health services. During climate emergencies, such as in Rio Grande do Sul, healthcare services are interrupted, delaying diagnosis and treatment. These challenges highlight the need for preventive public health policies that account for climate impacts, alongside measures to ensure swift restoration of health services for TB control.29

In Rio Grande do Sul—although some targeted measures were implemented—the long-term impact of this catastrophe is still unfolding and cannot yet be measured, as Brazil’s TB notification system is not online. Developing a system for real-time case reporting is crucial for emergency responses. Such a system would improve monitoring, enable timely interventions and allow for the evaluation of response effectiveness.

Challenges persist in strengthening health system resilience. Adequate funding for health infrastructure, especially in vulnerable areas, is essential to mitigate the effects of future crises. Training health professionals to manage climate emergencies and infectious disease outbreaks must also be prioritised. Effective collaboration and resource allocation are fundamental to bolstering SUS’ capacity to respond to climate-related crises.

Civil society plays a critical role in addressing the challenges posed by climate change. Local communities contribute to disseminating information, supporting campaigns and adopting preventive measures. Strengthening community networks and empowering local leaders, in conjunction with public policies, ensures health interventions reach the most affected populations, fostering equity in disaster responses.

Digital health technologies, such as telemedicine and electronic health records, offer valuable tools for ensuring care continuity during emergencies. These innovations support real-time patient tracking, remote consultations and improved coordination among sectors. By integrating digital tools into one health strategies, health systems can enhance their capacity to address interconnected health, environmental and social vulnerabilities.

The one health approach is critical for addressing climate change’s interconnected impacts on human, animal and environmental health.30 Cross-sector collaboration mitigates vulnerabilities like food insecurity and overcrowding, which exacerbate TB risks. By incorporating one health principles and leveraging digital technologies, TB control efforts can become more comprehensive, resilient and equitable.

Adopting these strategies, along with advancing TB vaccine development, is essential for mitigating climate change’s health impacts. Expanding cross-sector collaboration with education, infrastructure and environmental policies is key. A resilient response requires integrated efforts to protect vulnerable populations. Only through comprehensive and multisectoral strategies can Brazil effectively address the challenges posed by climate change.