Herpes Zoster: Understanding the Rising Burden in Latin America
Herpes zoster (HZ), commonly known as shingles, is a painful condition affecting millions worldwide. While often dismissed as a minor ailment, HZ can lead to debilitating pain, persistent complications, and a significant impact on quality of life. Recent research highlights a growing burden of HZ, particularly in Latin America, with Argentina emerging as a key area of concern. This article examines the epidemiology of HZ in the region, focusing on recent findings and the urgent demand for preventative measures.
What is Herpes Zoster?
Herpes zoster is a reactivation of the varicella-zoster virus (VZV), the same virus that causes chickenpox. After a chickenpox infection, the VZV remains dormant in nerve cells. As individuals age or experience weakened immune systems, the virus can reactivate, causing a painful rash typically appearing on one side of the body. The most common complication is postherpetic neuralgia (PHN), a chronic pain condition that can persist for months or even years after the rash has healed. Other complications include ocular involvement, neurological issues, and dermatological problems.
The Burden of Herpes Zoster in Argentina
A retrospective cohort study conducted at the Italian Hospital of Buenos Aires (HIBA) Health Plan from 2010 to 2022 revealed a substantial HZ burden in Argentina. The study, which followed an average of 138,977 members annually, recorded 8,122 cases of HZ. This translates to a mean incidence of 4.50 cases per 1,000 person-years (95% confidence interval: 4.15–4.85).1
The incidence of HZ demonstrably increases with age. The lowest incidence was observed in adults aged 18–29 years (1.87 cases per 1,000 person-years), while the highest incidence was found in those aged 80–89 years (7.27 cases per 1,000 person-years).1
The HIBA study also examined the frequency of complications. Postherpetic neuralgia (PHN) was observed in 50.85 cases per 1,000 HZ patients (95% CI: 37.31–64.39).1 The median duration of PHN was 981 days (interquartile range: 487–1,718 days). Additional complications included cutaneous issues (31.3 cases/1,000 HZ cases), ophthalmic involvement (6.0 cases/1,000 HZ cases), and neurological complications (1.85 cases/1,000 HZ cases). Recurrent HZ occurred in 4.25% of cases, with a median time to recurrence of 815 days (interquartile range: 308–1,890 days).
Regional Trends in Latin America
The increasing burden of HZ isn’t limited to Argentina. A systematic review and meta-analysis of Herpes Zoster epidemiology in Latin America and the Caribbean (LAC) revealed limited data, but highlighted a significant impact, particularly in high-risk populations.23 The review, which analyzed studies published between 2000 and 2020, found cumulative incidence ranging from 318 to 3,423 cases per 100,000 persons per year of follow-up in higher-risk groups. Incidence density ranged from 6.4 to 36.5 cases per 1,000 person-years.23
Age was consistently identified as a major risk factor, with incidence significantly increasing in individuals over 50 years of age. Hospitalization rates ranged from 3% to 35.7%, and in-hospital mortality rates varied from 0% to 36%. HZ mortality rates were also found to be higher in females across all age groups and countries.23
The Need for Prevention
The findings from Argentina and the broader Latin American region underscore the critical need for HZ prevention strategies. While acyclovir remains a frequently used therapy, preventative measures, such as vaccination, are essential to reduce the incidence of HZ and its debilitating complications. Further research is needed to fully understand the epidemiology of HZ in Latin America and to develop targeted prevention programs.
Key Takeaways:
- Herpes zoster is a painful condition caused by the reactivation of the varicella-zoster virus.
- The incidence of HZ increases with age and is a growing concern in Latin America.
- Argentina has a significant HZ burden, with a mean incidence of 4.50 cases per 1,000 person-years.
- Postherpetic neuralgia is the most common and debilitating complication of HZ.
- Preventative measures, including vaccination, are crucial to reduce the impact of HZ.