Varicella is typically mild and self-limiting, but can be associated with complications and even death. The limited data available on varicella in Latin America and the Caribbean (LAC) indicate substantial burden in countries where varicella vaccine is not part of publicly funded childhood national immunization programs. A systematic literature review of published studies was complemented by “gray” literature on varicella incidence, complications, mortality, and economic consequences, in the absence and presence of universal varicella vaccination (UVV) in LAC. Seroprevalence data indicate that varicella is usually a disease of childhood in LAC. Varicella incidence rates, while unreliable in the absence of mandatory reporting, show a trend to increased incidence due to greater urbanization and population density. The introduction of UVV in national immunization programs has led to significant reductions in varicella incidence in these areas. Varicella continues to pose a substantial healthcare burden in LAC. The future introduction of UVV in additional countries is predicted to provide substantial reductions in cases, with important economic benefits. For countries that have already implemented UVV, the challenge is to maintain high rates of coverage and, where relevant, consider inclusion of a second dose to reduce breakthrough cases. Given the significant proportion of the region now implementing UVV, a regional recommendation in order to prevent any potential for age-shifts in varicella infection might be considered.

The pneumococcal conjugate vaccination (PCV) was introduced into the Brazilian Childhood National Immunization Program in 2010; however, universal pneumococcal vaccination for older adults has not been implemented yet. Our aim is to evaluate the trends in pneumococcal meningitis incidence and case fatality rate (CFR) across all age groups from 2007 to 2019 using data from the National Surveillance System. The pre-PCV (2007–2009) and post-PCV (2011–2019) periods were compared; changes in incidence and CFR were assessed by joinpoint regression. Additional analyses of bacterial meningitis were performed to compare the patterns and trends. Over the 13-year period, 81,203 and 13,837 cases were classified as bacterial and pneumococcal meningitis, respectively. S. pneumoniae was the main etiological agent of bacterial meningitis in adults aged ≥50 years and the most lethal in all age groups. In the post-PCV period, a 56.5% reduction in the average incidence was seen in pneumococcal meningitis in the pediatric population. In contrast, there was an increasing trend among adults. The CFR for pneumococcal and bacterial meningitis remained stable in most age groups during the study period. These findings highlight the value of expanding pneumococcal vaccination policies, including vaccines that provide better indirect protection from children to adults and broadening vaccination to older adults.

One-dose universal varicella vaccination (UVV) was introduced in the Argentinian National Immunization Program in July 2015. This study examined the impact of one-dose UVV on varicella incidence and mortality in Argentina. Incidence and mortality data were obtained from official databases for pre-UVV (January 2008–June 2015) and post-UVV (July 2015–December 2019) periods. Time series analyses with autoregressive integrated moving average (ARIMA) modeling predicted varicella incidence and mortality in absence of UVV in the target (aged 1–4 years) and overall population. Predicted and observed values post-UVV were compared to estimate UVV impact. Mean annual incidence rates per 100,000 reduced from 1999 (pre-UVV) to 1122 (post-UVV) in the target population and from 178 to 154 in the overall population. Significant declines in incidence were observed, reaching reductions of 83.9% (95% prediction interval [PI]: 58.9, 90.0) and 69.1% (95% PI: 23.6, 80.7) in the target and overall populations, respectively, during peak months (September-November) post-UVV. Decreasing trends in mortality rate from 0.4 to 0.2 per 1,000,000 population were observed. Over the last four years, one-dose UVV has significantly reduced varicella burden of disease in Argentina. Continuous efforts to improve vaccination coverage rates and long-term follow-up are needed to better understand the benefits of the UVV program.

The HPV vaccination program in Brazil, introduced in 2014 for girls and 2017 for boys, aims to reduce HPV-related diseases, including anogenital warts (AGW) and high-grade cervical intraepithelial neoplasia (CIN). This descriptive ecological study evaluated the program’s impact on hospitalizations for AGW and high-grade-CIN using interrupted time series analysis of data from the Brazilian Hospital Information System from 2011 to 2019. From 2011 to 2019, there were 4,312 AGW hospitalizations among females, 7,295 AGW hospitalizations among males, and 84,306 hospitalizations for high-grade CIN. Following the implementation of the HPV vaccination program, significant reductions in hospitalizations for AGW and high-grade CIN were observed, particularly in the targeted 15–19-year-old age group. In this group, the median number of hospitalizations prevented was 174 (95% CI: 154–193) for AGW among females, 116 (95% CI: 86–147) for AGW among males, and 217 (95% CI: 94–339) for high-grade CIN, with strong model fits. Downward trends were also noted in older age groups, though with poorer model fits. The HPV vaccination program has significantly reduced hospitalizations for AGW and high-grade CIN in Brazil, particularly among the targeted age group. Local evidence of early disease benefits reinforces the importance of HPV immunization in reducing the burden of HPV-related diseases and support expanding vaccination efforts for broader public health benefits. Reductions of AGW and high-grade CIN in older age groups may reflect indirect vaccination effects and treatment strategies, respectively.

This review aimed to characterize adolescent vaccination schedules in publicly funded national immunization programs in Latin America and the Caribbean. The initial review identified vaccine type, target age and gender, dose schedule, and vaccination coverage rate (VCR) across 50 countries/territories in the region. A systematic review from January 2010-October 2023 was then conducted to identify primary data collection studies reporting VCRs. Overall, 42 webpages and 23 primary studies were identified. Among 47 countries/territories with ≥1 vaccine for adolescent immunization, human papillomavirus (HPV) vaccine was included in 45, tetanus component vaccines in 43, and meningococcal vaccines in 10. Catch-up vaccination for hepatitis B in 17, and yellow fever in all 13 endemic countries/territories. VCRs were primarily available for HPV. The findings of this review underscore the need to prioritize adolescent vaccination, improve accessibility, and strengthen tracking infrastructure to ensure comprehensive protection of this age group across the region.