The intense pain experienced by a person with herpes zoster often makes them completely incapable. And in the event of a complication - the so-called postherpetic neuralgia - the torment of a patient lasts for months, even years...

In the United States, approximately 1 million cases of infection caused by the Herpes zoster virus are recorded each year. Unfortunately, doctors do not have enough information about the risk factors for the development of the disease: with confidence, only two of them can be listed: age and immunosuppression. To date, there is evidence of the effectiveness of the herpes zoster vaccine (Zostavax, Merck & Co., Inc.) in reducing the risk of developing the disease, but they were obtained with the participation of a selection of the population studied and under practically idealized conditions which take place only theoretically. Therefore, data on the effect of the vaccine under normal conditions should be available.

In 2006, the U.S. Food and Drug Administration (FDA), in accordance with the recommendations of the U.S. Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices, granted permission to use the Vaccine, special attention being given to elderly people suffering from absence of contraindications (taking immunosuppressive drugs, blood diseases (leukemia, lymphoma), documented positive HIV status, presence of allergic reactions to the components of the other vaccine). The last update was officially dated 2007, when the vaccination program came into effect.

A study on the prevention of herpes zoster (and called the shingles prevention study, SPS) has shown that the use of a vaccine prepared using the strain Oka / Merck varicella zoster reduced the incidence of infection by 51%. % (P less than 0.001) and postherpetic neuralgia of 67% (P less than 0.001). It should be noted that the study participants were 38,546 people over the age of 60 who had no history of infection caused by Herpes zoster, immunosuppression or any other condition that would make it impossible for the patient to participate in the study (N Engl J Med.2005; 352: 2271-84).

The purpose of this study was to determine the risk of developing shingles in a wide range of people who sought medical care in general practice with symptoms of herpes infection.

The main objective of the research team led by Dr Tseng was to assess the applicability of data on the efficacy of the vaccine in standard clinical practice, and in particular in patients in the older group, for whom the vaccine is not only allowed, but also recommended. In addition, the researchers did not ignore the strict storage requirements of the live attenuated vaccine studied, as well as the vaccination procedure itself.

From January 1, 2007 to December 31, 2009, a retrospective cohort study was conducted which analyzed the medical records of patients who sought help from the Kaiser Permanente Clinic, Southern California. To participate in the study, immunocompetent patients aged 60 and over living in municipal housing were selected. 75,761 study participants vaccinated were selected based on the age of 227,283 subjects who did not receive the vaccine, in a ratio of 1: 3.

During the study, the incidence of infection caused by Herpes zoster was considered the main criterion evaluated.

During the process, it turned out that among the vaccinated patients, the majority were Europeans, women, were treated on an outpatient basis and had a small number of concomitant diseases.

The number of infections among vaccinated individuals was 828 out of 130,415 person-years (6.4 per 1,000 person-years; 95% confidence interval 5.9-6.8); for unvaccinated people, 4,606 per 355,659 person-years (13.0 per 1,000 person-years; 95% CI 12.6–13.3). In a corrected analysis, it was found that vaccination is associated with a 55% reduction in the risk of infection with Herpes zoster (odds ratio 0.45, 95% CI 0, 42 to 0.48); a similar trend occurred in all age groups and in people with chronic illnesses. The risk of contracting herpes zoster much more than the risk of any other acute condition has been determined by vaccination status, so the results are not the result of systematic error. Ophthalmic herpes caused by herpes zoster (OR 0.37; 95% confidence interval, 0.24-0.51) and hospitalizations due to the development of infection by herpes zoster were much less common. in vaccinated individuals. It should be noted that among people over 80 years of age, the effectiveness of vaccination was evident. Compared to this last fact, the data obtained differ from those of the SPS study.

According to the authors, given the short legalization period for the use of the vaccine (4 years), additional studies are needed to more fully assess its effectiveness.

However, already at this stage of research work, it is clearly noted that during the use of the vaccine, the development of many cases of Herpes zoster infection and post-herpetic neuralgia can be avoided every year.

Unfortunately, in practical health care, vaccination against herpes zoster is very rare. This can be explained in part by a poorly organized infrastructure, as well as a lack of understanding of the need for vaccination, which occurs both among patients and among the doctors themselves. The solution to the problems that arise is, first of all, the realization that the vaccinated person will be able to protect themselves against the disease or, at least, to reduce the probability of its occurrence. The elderly, who are much more susceptible to infections, are particularly dangerous. Each doctor consulted by a patient with the intention of being vaccinated must individually assess all the indications and contraindications for administering the vaccine.

It should be noted that the criticisms received for the study are not unambiguous. For example, Karen Roos, professor of neurology and neurosurgery, member of the American Academy of Neurology, points out certain important limits from her point of view, in particular a retrospective study plan and a rather short observation period. The question naturally arises concerning the period of time during which protective immunity will be maintained. It is unclear whether those vaccinated will be adequately protected for one, two, three or more years.

In addition, there is no information on adverse events that coincided with vaccination. For example, in the SPS study, there are indications of a higher percentage of cardiovascular events associated with the vaccination procedure.

However, despite all the positive and negative points, the conclusion is obvious: among immunocompetent immunized patients living in municipal dwellings over the age of 60, there has been a decrease in the incidence of infection caused by Herpes zoster, with a reduced risk of the disease It was noted in all the age groups studied and in people with chronic diseases.