Resurgent Diseases: A Warning Sign for Public Health in the 21st Century
A quiet alarm is sounding in public health circles. Diseases once considered relics of the past – syphilis, measles, tuberculosis – are showing signs of a worrying comeback. Recent data, particularly from Quebec, Canada, paints a concerning picture, prompting experts to warn of a potential erosion of hard-won gains in infectious disease control. This isn’t simply a localized issue; it’s a global trend with potentially far-reaching consequences.
The Declining Shield: Vaccination Rates and Immunity Gaps
At the heart of this resurgence lies a decline in vaccination rates. Dr. Caroline Quach-Thanh, National Director of Public Health in Quebec, emphasizes that reduced vaccine coverage directly correlates with increased cases of preventable diseases. “The first thing we see when vaccination coverage declines is a resurgence of measles,” she states, “but if all other vaccines continue to decline, there’s nothing to say we won’t see cases of polio again.”
The principle of herd immunity – where a high percentage of the population is immune, protecting those who cannot be vaccinated (infants, immunocompromised individuals) – is being compromised. As vaccination rates slip, this protective barrier weakens, leaving communities vulnerable. Recent polio virus detections in wastewater in Germany, despite no confirmed cases, serve as a stark reminder of how easily these diseases can re-emerge.
Pro Tip: Check your family’s vaccination records and consult with your healthcare provider to ensure everyone is up-to-date. Resources like the Centers for Disease Control and Prevention (CDC) offer comprehensive vaccination schedules.
Tuberculosis: A Persistent Threat, Especially for Vulnerable Populations
Tuberculosis (TB), a disease with roots stretching back millennia (evidence found in Egyptian mummies dating to 2400 BC), remains a significant global health challenge. The World Health Organization (WHO) estimated 10.8 million new cases of active TB in 2023, a 2-3% annual increase since 2020. Quebec is experiencing its own surge, with 493 cases reported in 2025 (as of December 13th), with a disproportionate concentration in the Nunavik region.
The situation in Nunavik highlights the complex interplay between health and social determinants. Overcrowded housing conditions facilitate transmission, while systemic challenges hinder access to healthcare and treatment. Addressing TB in Nunavik requires a multi-faceted approach, encompassing not only medical interventions but also improvements in housing and social support systems.
Measles: Losing Ground After Decades of Progress
Measles, once declared eliminated in Canada in 1998, has lost its status due to recent outbreaks. Alberta and Ontario have been particularly affected, with over 2000 cases reported. To achieve herd immunity, vaccination coverage needs to exceed 95%. Currently, Quebec’s coverage varies significantly by region, ranging from 83% to 96%.
The ease of international travel means that a single imported case can quickly spark a local outbreak, especially in areas with low vaccination rates. This underscores the importance of maintaining high vaccination coverage globally to prevent the re-establishment of measles transmission.
Syphilis: A Concerning Rise in Congenital Cases
Syphilis, an ancient sexually transmitted infection, is also experiencing a resurgence, particularly among men who have sex with men, but increasingly in heterosexual populations, especially women of childbearing age. The most alarming trend is the rise in congenital syphilis – babies born with the infection – indicating gaps in prenatal screening and treatment.
Dr. Quach-Thanh stresses the preventability of congenital syphilis, emphasizing the need for consistent prenatal testing and timely treatment of infected mothers. Public health initiatives are exploring strategies to repeat syphilis testing in the third trimester of pregnancy and at birth to ensure no cases are missed.
The Role of Societal Factors and Pandemic Aftermath
Dr. Karl Weiss, Head of Infectious Diseases at the Jewish General Hospital, points to a shift in societal attitudes towards vaccination. “We’ve become a ‘rich’ society where we have the luxury of questioning whether or not to vaccinate our children,” he observes. This contrasts sharply with previous generations who lived through the devastating consequences of these diseases and viewed vaccination as a non-negotiable safeguard.
The COVID-19 pandemic also played a role, albeit indirectly. Lockdowns and travel restrictions temporarily suppressed the spread of many infectious diseases. However, as societies reopened, these diseases re-emerged, highlighting their dependence on human interaction and mobility.
Looking Ahead: Strategies for a More Resilient Future
Public health officials are employing various strategies to improve vaccination coverage, including programs like EMMIE, which provides unbiased vaccination counseling to new parents. However, a shift towards education and dialogue, rather than mandatory vaccination, is the preferred approach in Quebec.
Did you know? The EMMIE program aims to address vaccine hesitancy by providing parents with evidence-based information and a safe space to ask questions.
Ultimately, combating the resurgence of infectious diseases requires a collective effort. It demands a renewed commitment to vaccination, investment in public health infrastructure, and a recognition that these diseases are not relics of the past but persistent threats that require ongoing vigilance.
FAQ
Q: Why are vaccine rates declining?
A: Several factors contribute, including misinformation, vaccine hesitancy, access barriers, and complacency due to the perceived rarity of these diseases.
Q: Is polio a real threat again?
A: While polio has been eradicated in most of the world, the detection of the virus in wastewater in countries like Germany indicates a risk of re-emergence, especially in areas with low vaccination coverage.
Q: What can I do to protect myself and my family?
A: Ensure everyone is up-to-date on their vaccinations, practice good hygiene (handwashing, covering coughs), and consult with your healthcare provider if you have any concerns.
Q: Why is tuberculosis so prevalent in Nunavik?
A: Overcrowded housing, limited access to healthcare, and underlying social determinants of health contribute to the high TB rates in the region.
Want to learn more about infectious disease prevention? Explore our other articles on public health or subscribe to our newsletter for the latest updates.
