Annual incidence rates of herpes zoster among an immunocompetent population in the United States

Abstract

BackgroundHerpes zoster (HZ), also known as shingles, is a painful and commonly occurring condition in the United States. In spite of a universally recommended vaccine for use in immunocompetent adults aged 60 years and older, HZ continues to impact the American public, and a better understanding of its current incidence is needed. The objective of the current study is to estimate the overall and age- and gender-specific incidence rates (IRs) of HZ among an immunocompetent US population in 2011 following availability of a vaccine.MethodsClaims data from the Truven Health MarketScan® Research databases between 01/01/2011 and 12/31/2011 were extracted. Immunocompetent adult patients, enrolled as of January 1, 2011 were analyzed. The denominator was defined as eligible subjects who were immunocompetent, had no evidence of zoster vaccination, and no diagnosis of HZ (International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code 053.xx) in the 90 days prior to January 1, 2011. Subjects contributed person-days to the denominator until the occurrence of one of the following events: end of continuous enrollment in the database, a claim for zoster vaccination, diagnosis of HZ or end of the observation period (December 31, 2011). The numerator was defined as enrollees within the denominator file exhibiting evidence of HZ. Annual IRs were calculated for the entire population in the database as well as by gender and age group; standardized IRs were also produced using the 2010 US Census data.ResultsThe overall annual IR of HZ across all ages was 4.47 per 1000 person-years (95 % confidence interval [CI]: 4.44–4.50) which monotonically increased with age from 0.86 (95 % CI: 0.84–0.88) for those aged ≤19 to 12.78 (95 % CI: 12.49–13.07) for patients ≥80 years. The IR was 8.46 (95 % CI: 8.39–8.52) among adults ≥50 years and 10.46 (95 % CI: 10.35–10.56) among those aged ≥60 years. Women compared to men had higher HZ incidence (5.25, 95 % CI: 5.21–5.29 vs. 3.66, 95 % CI: 3.62–3.69) and this was seen across all age groups. When adjusted for age and gender using 2010 US Census data, the annual IR was 4.63 per 1000 person-years (95 % CI: 4.61–4.66).ConclusionsDespite the availability of a vaccine, HZ remains common among immunocompetent adults in the US with incidence rates of HZ observed to increase with age and be higher in women than men.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-015-1262-8) contains supplementary material, which is available to authorized users.

The bowel and beyond: the enteric nervous system in neurological disorders

“…In a small clinical trial of patients in whom salivary VZV DNA caused enteric zoster to be suspected, treatment of three of three patients with the antiviral drug valaciclovir was followed by the rapid disappearance of abdominal pain 144 . Because zoster is associated with a decrease in cellular immunity 150 , population ageing and the increasingly common use of immunosuppressive therapies have caused the incidence of zoster in the USA to rise by about threefold since studies carried out between 1945 and 1959; similar rises have been reported in other developed countries 151 . The use of salivary VZV DNA for the diagnosis of zoster has already revealed that enteric zoster is not rare 144 , and once it begins to be widely suspected, this pathology is likely to be encountered with increasing frequency.…”

The Prevention of Infections in Older Adults: Vaccination

“…The rash is painful and is often accompanied by malaise, headache, and other generalized symptoms. The individual lifetime risk of zoster is 30%, with approximately 1 million new cases annually in the United States . Incidence increases with age, increasing from 0.86 per 1000 in those aged 19 years or younger to 12.78 per 1000 in those ages 80 years or older .…”

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“…In many developed countries, there has been a gradual increase in zoster incidence over time that predates the introduction of varicella vaccine and may relate to changing social or environmental conditions. Overall zoster incidence is 2.0–4.6 cases per 1000 person years rising to 10.0–12.8 cases per 1000 person years in people aged 80 years or over [27,28]. Both the incidence and severity of zoster increase with age, with complications occurring in almost half of older people with zoster [29].…”