Background The contemporary national epidemiological surveillance system of sexually transmitted infections in Lithuania was legalised in 2009. A national computerised reporting system has been introduced, aiming to standardise the data collection and analysis for all communicable diseases and their etiological agents through the country.

Methods Analysis of the national database available at www.ulac.lt

Results There are four reportable STIs in Lithuania, namely syphilis, Chlamydia trachomatis, Neisseria gonorrhoeae and HIV. Since 2010 both the physicians and the laboratories report identified STI cases. The physician reports individual new STI cases weekly, while the laboratory reports are provided monthly and only as aggregated data. During the period of 2009–2011, the incidences of bacterial STIs in Lithuania have been decreasing. The incidence (cases per 100,000 population) of syphilism decreased from 9.6 to 8.5 cases, of gonorrhoea from 11.5 to 7.9 cases, and of genital C. trachomatis infection from 11.9 to 10.6. In contrast, the incidence of HIV infection during the same time period increased from 0.49 to 5.15 cases! These changes in STI incidences were not due to the level of testing, which has been relatively stable from 2009 to 2011.

Conclusion The substantial increase in HIV incidence during recent years in Lithuania is of major concern. The difference in reporting methodologies, namely reporting of individual cases by the physicians and aggregated data from the laboratory reports does not allow comparison of them sufficiency of such reporting as well as evaluation of the true epidemiological situation.