Prevalence of hepatitis C antibodies in the population aged 16-80 years in the Community of Madrid 2008-2009.

Together with AIDS, the burden of hepatitis C virus (HCV) in Spain heads the list of communicable diseases in terms of impact on public health. The aim of this study was to estimate the prevalence of HCV antibodies in the Community of Madrid, assess changes in recent years and analyse associated risk factors. Descriptive cross-sectional study of a target population consisting of Community of Madrid residents aged 16-80 years old. Two-stage cluster sampling was performed, with stratification by socioeconomic status and percentage immigrant population. The sampling frame consisted of public blood extraction centers attached to the Madrid Health Service. Seroprevalence of HCV antibodies, prevalence ratios by age groups in comparison with 1999 survey data and prevalence association with risk factors were assessed using a logistic regression model. Prevalence of HCV antibodies for the age group 16-80 years was 1.8% (95% CI: 1.3-2.5). The age group with the highest prevalence was 41-60 years. In comparison with the 1999 survey, prevalence fell for the age groups 21-30 and 31-40 years and increased for the age group 41-60. Statistically significant associations were found for age, education, history of hepatitis C and consultation regarding liver problems. Seroprevalence of HCV antibodies in the Community of Madrid is similar to that shown in other regions of Spain. It is increasing in older age groups as the population at risk ages. Incidence of hepatitis C may be decreasing considering the decrease in the seroprevalence in the population younger than 40 related to the previous serosurvey.

Varicella and herpes zoster in Madrid, based on the Sentinel General Practitioner Network: 1997-2004.

BACKGROUND: Varicella (chickenpox) is the primary disease caused by varicella-zoster virus. It is extremely contagious and is frequent in children. Indeed, in the absence of vaccination, a high proportion of the population is liable to contract it. Herpes zoster -more frequent among adults- is caused by reactivation of the latent virus. The objective of this study is to describe the status of and time trend for varicella and herpes zoster in the Madrid Autonomous Region prior to the introduction of the vaccine to the general population. DATA SOURCE: individualised varicella and herpes zoster case records kept by the Madrid Autonomous Region Sentinel General Practitioner Network for the period 1997-2004. Cumulative incidences, crude and standardised incidence rates, and age-specific rates of varicella and herpes zoster were calculated for each year. Kendall's Tau-b correlation coefficient was calculated to evaluate whether incidence displayed a time trend. Spectral density in the time series of weekly incidences was estimated using a periodogram. RESULTS: Standardised annual varicella incidence rates ranged from 742.5 (95% CI: 687.2-797.7) to 1239.6 (95% CI: 1164.5-1313.4) cases per 100 000 person-years. Most cases affected children, though complications were more frequent in adults. Varicella incidence displayed an annual periodicity but no trend over time. Most herpes zoster cases occurred at advanced ages, with incidence registering a rising annual trend but no seasonality factor. CONCLUSION: In the absence of vaccination, no significant changes in varicella incidence were in evidence recent years, though these were observed in the incidence of herpes zoster. Sentinel general practitioner networks are a valid instrument for surveillance of diseases such as varicella. Further varicella vaccination-coverage and vaccine-efficacy studies are called for.