Over 90% of adults have latent herpes zoster virus in their bodies!

2023-12-09

Shingles is a painful rash caused by the reactivation of the chickenpox virus. Without vaccination, the lifetime risk of developing shingles in the general population is 30%. Relevant studies show that more than 90% of adults have the "herpes zoster virus" lurking in their bodies. As age increases, the function of the immune system declines, and the risk of developing herpes zoster shows an increasing trend.

Complications and major clinical outcomes of shingles include: postherpetic neuralgia (pain in the rash area that persists for several months), ocular herpes zoster (the rash occurs in or around the eyes), hospitalization for shingles, etc. . Among patients diagnosed with herpes zoster, approximately 5% to 30% develop postherpetic neuralgia, 9% to 25% develop ocular herpes zoster, and 1% to 4% are hospitalized for herpes zoster.

Recently, a prospective cohort study published in The British Medical Journal (THE BMJ) evaluated the 10-year long-term effectiveness of live herpes zoster vaccine in people aged 50 years and above. The analysis showed that the live shingles vaccine was most effective when initially administered and that its effectiveness declined significantly over time (although it still provided some protection 10 years after vaccination). Ten years after vaccination with the live herpes zoster vaccine, the vaccine was less effective in preventing the incidence of herpes zoster, but it remained relatively effective in preventing postherpetic neuralgia.

The current real-world cohort study is based on electronic health record data of more than 1.5 million subjects (≥50 years old) in the KPNC (Kaiser Permanente Northern California) system in the United States, and evaluates the effectiveness of the live herpes zoster vaccine in preventing herpes zoster, shingles, and shingles. Effectiveness in post-herpetic neuralgia, ocular herpes zoster, etc. Overall, these subjects were followed for nearly 9.4 million person-years (January 1, 2007, to December 31, 2018).

Statistics show that among the 1,505,647 subjects included in the study, 507,444 (34%) subjects were vaccinated with live herpes zoster vaccine. By the end of the study, the vaccination coverage rate for people aged 60-69 years and ≥80 years old exceeded 60%; the vaccination coverage rate for people aged 70-79 years old exceeded 80%; the vaccination coverage rate for people aged 50-59 years old was lower. (<5%). About 5.7% of the vaccinated population were immunocompromised at the time of vaccination (1.2% of them were highly immunocompromised).

During the follow-up period, a total of 75,135 new cases of herpes zoster occurred in the subjects, of which 4,982 (7%) developed postherpetic neuralgia, 4,439 (6%) developed ocular herpes zoster, and 556 ( 0.7%) were admitted to hospital due to herpes zoster.

For the unvaccinated population, the incidence rates of herpes zoster, postherpetic neuralgia, ocular herpes zoster, and hospitalization for herpes zoster were approximately 863.2/100,000 person-years and 57.2/100,000 people, respectively. -year, 48.9/100,000-year, 6.9/100,000-year. The incidence of these clinical outcomes increases with subject age (especially postherpetic neuralgia and hospital admission for herpes zoster).

In every age group, the incidence of each clinical outcome was lower in vaccinated people than in unvaccinated people (except for those aged 50 to 59 years old who were hospitalized for herpes zoster, for which the incidence of this clinical outcome was the same in both vaccinated and unvaccinated people). lower).

In terms of preventing the occurrence of four clinical outcomes: herpes zoster, postherpetic neuralgia, ocular herpes zoster, and hospitalization for herpes zoster, the effectiveness of the vaccine is highest in the first year after vaccination, and then increases over time. significantly weakened. in particular:

In terms of preventing shingles, the vaccine's effectiveness was 67.2% in the first year, dropped to 49.6% in the second year, and gradually dropped to 14.9% between years 10 and 12;

The vaccine's effectiveness in preventing postherpetic neuralgia was 83.0% in the first year, decreasing to 41.4% between years 10 and 12;

In preventing ocular herpes zoster, the vaccine was 70.6% effective in the first year, falling to 29.4% between years 5 and 8;

The vaccine was 89.5% effective in preventing hospitalization for shingles in the first year, falling to 52.5% between years 5 and 8.

Over all follow-up times, the vaccine was 45.7% overall effective in preventing herpes zoster, 62.3% overall effective in preventing postherpetic neuralgia, and 62.3% overall effective in preventing ocular herpes zoster. was 44.5%, with an overall effectiveness of 65.9% in preventing hospitalization for shingles.

Ten years after vaccination, the average effectiveness of the vaccine in preventing herpes zoster, postherpetic neuralgia, ocular herpes zoster, and hospitalization for herpes zoster was 38.1%, 59.0%, 36.6%, and 64.2, respectively. %.

In addition, vaccine effectiveness is generally similar across different population subgroups (e.g., different age, gender, race/ethnicity, immune function status at the time of vaccination).

Taken together, the results of the analysis from the current study show that the effectiveness of the live herpes zoster vaccine is highest during the first year after vaccination and then declines substantially over time.

The study highlights that the incidence of herpes zoster-related clinical outcomes increases significantly with age in the population, but vaccine effectiveness decreases slightly with the age of the recipients. From the perspective of absolute benefit, the benefits of vaccination increase as the age of the population increases. Vaccination with live herpes zoster vaccine will also benefit the elderly (such as those aged 80 and above).