It is a sign of enormous progress that vaccines are currently available to prevent more than 20 life-threatening diseases. And health and economic data supports the widespread benefits of regular access to vaccination in public health. Yet it is estimated that 20 million infants or so each year do not have access to vaccination for a number of diseases, including varicella (also known as “chickenpox”).

This problem is particularly acute in Latin America and the Caribbean. And the experts convened for a recent webinar, ‘Vaccinating the Americas: Lessons from Varicella Vaccination,’ organized by the Wilson Center and Americas Health Foundation, used the occasion to highlight the widespread challenges facing routine immunization programs following COVID-19.

In particular, the public health community faces a serious challenge in recovering and prioritizing vaccination especially during times of disruptions to the system. Dr. Alejandro Cravioto, president of the World Health Organizations (WHO) Strategic Advisory Group of Experts on Immunization, stated that the COVID-19 pandemic created delays in vaccination programs around the world. And as vaccination clinics either closed or reduced services during the pandemic, millions of children missed out on vaccines against preventable diseases.

The result is that chickenpox and measles infections have risen. Given the impact of these diseases, the risks of greater exposure are not only faced by the region’s children. They could also have a grave impact on healthcare systems in Latin America.

The urgency in improving access is apparent. Felicitas Colombo, Director of Government and Public Affairs at the Americas Health Foundation, noted that the WHO has identified immunization as “a global public health and development achievement that saves millions of lives every year.”

The panelists also discussed how governments can strengthen public health systems to respond more efficiently to vaccination needs in the region. One specific focus was the up to 20 percent decline in varicella vaccination rates due to the re-direction of healthcare priorities and resources during the pandemic. The experts also emphasized the importance and economic benefit to society of including varicella in public health vaccination programs.

Varicella in Latin America

Varicella is a serious disease in young children that must be prioritized in public health programs, said Dr. Mirella Vázquez Rivera, Treasurer of the Mexican Association of Pediatric Infectious Diseases. While the varicella mortality rate is fairly low, 40 percent of children who contract it will experience some sort of side effect or complication. The disease poses a significant threat to children under five years of age. They not only have the highest varicella mortality rate, but these children are also vulnerable to secondary complications such as pneumonia, encephalitis, skin and soft tissue infections, or sepsis.

The panelists said that varicella’s dangers for young children are accompanied by the considerable financial burden that the disease places on the public health sector. Yet they also emphasized that its impacts can be mitigated through regular vaccination. One example is Costa Rica, which introduced the varicella vaccine in its National Immunization Program. The results? A 73 percent reduction in the incidence of varicella cases and a 94 percent decrease in the rate of hospitalization in children under five years of age.

In Latin America, the incidence of varicella is about 22 cases per 1,000 people – well above the global average of 2 to 16 cases per 1,000 people. Dr. Vázquez Rivera observed that this statistical difference demonstrates the importance of immediate attention to varicella in Latin America. Her view was seconded by Dr. Cristina Mariño, a member of both the Society of Pediatrics, Society of Infectious Diseases, and National Committee on Immunization Practices in Colombia,

Dr. Mariño added that the incidence of varicella may be even higher than reported, in part because not all countries require mandatory reporting of varicella infections. And the panelists agreed that such reporting is a crucial step in understanding and reducing the incidence of varicella in Latin America.

Dr. Mario Melgar, a pediatrician who serves on the Guatemalan Association of Infectious Diseases and the National Council of Immunization Practices, said that the lack of a national varicella surveillance program makes it extremely difficult to assess the disease burden of varicella in Guatemala. Dr. Vázquez Rivera echoed his point, and argued that such reporting is necessary to understand the prevalence of varicella and to assess whether vaccines are working.

Varicella’s Economic Costs in Mexico

Panelists also highlighted the economic cost of varicella in Mexico (where the disease is not included in the National Immunization Program), especially given the associated costs to treat the disease and any secondary complications.

Dr. Vázquez Rivera reported that outpatient care costs, including doctor’s visits, medications, tests, and procedures, are estimated to be roughly US $240 dollars, or $4718 Mexican pesos. Inpatient mean costs, including hospitalization, are estimated to be US $5,786 dollars, or $113,454 Mexican pesos.

On a national scale, pediatric infectious disease specialist Dr. Enrique Chacón-Cruz noted that $165 million is spent on treating varicella cases every year. This economic analysis clearly showed the significant financial burden for governments and families caused by the disease, especially if a patient is hospitalized.

Dr. Chacon-Cruz also observed that the considerable expenditures for varicella treatment in Mexico indicate the need for public health efforts and political will to mitigate varicella infections through expanded use of vaccinations. Doing so would reduce infection rates and hospitalizations, hence reducing the economic burden on both public health agencies and patients alike.

Crafting Better Policies to Address Varicella in Latin America

The webinar panelists went beyond simply articulating the challenges facing Latin America in varicella vaccination to recommend a series of policies to address them.

These experts agreed that policymakers ought to work to expand access to varicella vaccination through innovative mechanisms to optimize service delivery and ensure that no child is left behind. Dr. Cravioto called for data systems to be improved to monitor vaccine administration and identify pockets of under-vaccination to inform catch-up campaigns and enhance surveillance capability. This would not only ensure accurate reporting of varicella disease burden, but also allow catch-up programs to be tailored to identify and locate children who missed doses.

There was also agreement that a diverse set of stakeholders should be engaged in order to increase public awareness of varicella disease and confidence in vaccination. Yet there may be more to do, Dr. Chacón-Cruz highlighted the importance of generating data on the health, economic, and societal benefits of varicella vaccination to drive political will for inclusion in national immunization programs. Utilizing evidence-based decision-making methodology, varicella vaccination should be included in all national immunization programs in Latin America.