Mariyana Stoycheva, Nikolay Vatev, Andrey Petrov, Chavdar Venchev, Maria Atanasova

Abstract: Background: Hepatitis A is a social disease and has great importance for public health in countries with high level of incidence rate. The problem is particularly serious for Bulgaria because the morbidity rate in the country is several times higher in comparison with the other countries of the European Union. The aim of the study is to establish the contemporary epidemiological characteristics of viral hepatitis A in Bulgaria. Methods: Analysis of the incidence rate and the age distribution has been done among two groups of the population differentiated depending on their hygienic living conditions: 1st group—living in bad hygienic conditions; 2nd group—living in good hygienic conditions. A large epidemic outbreak of hepatitis A with 1004 persons of Roma origin has been described. The comprehensive method for epidemiological research and serological methods for determining the diagnosis have been used. To study the risk factors the methods of case-control and multi-factor logistic regression are used. Results: Nine times higher incidence rate has been established in the 1st group 450/100,000 in comparison with the 2nd 50/100,000. The patients from the 1st group are predominantly children aged 5 - 9 years and from the 2nd adults aged 30 - 39 years. The level of significance of the risk factors for the biggest epidemic outbreak has been established—bad personal hygiene is of the greatest importance. The risk for travellers to countries and regions with high endemicity and during epidemic outbreaks has been shown. Conclusions: There are essential differences in the epidemiology of HAV between the groups with different hygienic living conditions. That is why the analyses of the incidence rate and age distribution of hepatitis A have to be done separately for different population groups. Recommendations for providing differentiated measures for prevention and control of hepatitis A among the two groups are given.

Keywords: Hepatitis A, Incidence Rate, Epidemic Outbreak, Risk Factors

Cite this paper: nullM. Stoycheva, N. Vatev, A. Petrov, C. Venchev and M. Atanasova, "Epidemiological Study of Hepatitis A in Plovdiv Region—Bulgaria, 2005-2008," World Journal of Vaccines, Vol. 1 No. 4, 2011, pp. 162-168. doi: 10.4236/wjv.2011.14017.

References

[1]   K. H. Jacobsen and J. S. Koopman, “Declining Hepatitis A Seroprevalence: A Global Review and Analysis,” Epidemiology and Infection, Vol. 132, No. 6, 2004, pp. 1005-1022. doi:10.1017/S0950268804002857

[2]   S. Krugman, J. P. Giles and J. Hammond, “Infectious Hepatitis. Evidence for Two Distinctive Clinical, Epidemiological and Immunological Types of Infection,” Journal of the American Medical Association, Vol. 200, No.5, 1967, pp. 365-373. doi:10.1001/jama.200.5.365

[3]   S. J. Staes, T. L. Schlenker, I. Risk, K.G. Cannon, H. Haris and A. T. Pavia, “Sources of Infection among Persons with Acute Hepatitis A and No Identified Risk Factors during a Sustained Community-Wide Outbreaks,” Pediatrics, Vol. 106, No. 4, 2000, pp. E54. doi:10.1542/peds.106.4.e54

[4]   P. Mathur and N. K. Arora, “Epidemiological Transition of Hepatitis A in India: Issues for Vaccination in Developing Countries,” Indian Journal of Medical Research, Vol. 128, No. 6, 2008, pp. 699-704.

[5]   G. De Serres, T. I. Cromeans, B. Levesque, M. Brassard, C. Barthe, M. Dionne, H. Prudhomme, D. Paradis, C. N. Shapiro, O. V. Nainan and H. S. Margolis, “Molecular Confirmation of Hepatitis A Virus from Well Water, Epidemiology and Public Health Implications,” Journal of Infectious Diseases, Vol. 179, No. 1, 1999, pp. 37-43. doi:10.1086/314565

[6]   S. M. Feinstone, A. Z. Kapikan and R. H. Purcell, “Hepatitis A: Detection by Immune Electron Microscopy of a Virus-Like Antigen Associated with Acute Illness,” Science, Vol. 182, No. 116, 1973, pp. 1026-1028. doi:10.1126/science.182.4116.1026

[7]   B. B. Goswami, W. Burkhardt and T. A. Cebula, “Identification of Genetic Variants of Hepatitis A Virus,” Journal of Virological Methods, Vol. 65, No. 1, 1997, pp. 95- 103. doi:10.1016/S0166-0934(97)02179-4

[8]   T. I. Cromeans, O. V. Nainan and H. S. Margolis, “Detection of Hepatitis A Virus RNA in Oyster Meat,” Applied and Environmental Microbiology, Vol. 63, No. 6, 1997, pp. 2460-2463.

[9]   J. Jean, B. Blais, A. Darvean and I. Fliss, “Detection of Hepatitis A Virus by Nucleic Acid Sequence-Based Amplification Technique and Comparison with Reverse Transcription-PCR,” Applied and Environmental Microbiology, Vol. 67, No. 12, 2001, pp. 5593-5600. doi:10.1128/AEM.67.12.5593-5600.2001

[10]   B. P. Bell, “Global epidemiology of hepatitis A: implications for control strategies,” In: H. S. Margolis, M. J. Alter, J. T. Liand and J. I. Dienstag, Eds., Viral Hepatitis and Liver Disease, International Medical Press, London, 2005, pp. 9-14,.

[11]   S. R. Bialek, D. A. Thoroughman, D. Hu, E. P. Simard, J. Chattin, J. Cheek and B. P. Bell, “Hepatitis A Incidence and Hepatitis A Vaccination among American Indians and Alaska Natives 1990-2001,” American Journal of Public Health, Vol. 94, No. 6, 2004, pp. 996-1001. doi:10.2105/AJPH.94.6.996

[12]   A. E. Fiore , A. Wasley and B. P. Bell, “Prevention of Hepatitis A through Active or Passive Immunization: Recommendations of the Advisory Committee on Immunization Practice (ACIP),” MMWR Recommendations and Reports, Vol. 55, No. RR-7, 2006, pp. 1-23.

[13]   N. S. Crowcroft, B. Walsh and K. L. Davison, “Gundabissoon U on Behalf of PHLS Advisory Committee on Vaccination and Immunization, Guidelines for the Control of Hepatitis A Virus Infection,” Communicable Disease and Public Health, Vol. 4, No. 3, 2001, pp. 213-227.

[14]   C. T. Leach, “Hepatitis A in the United States,” Pediatric Infectious Disease Journal, Vol. 23, No. 6, 2004, pp. 551- 553. doi:10.1097/01.inf.0000130071.03003.c2

[15]   B. Pham, B. Duval, G. De Serres, V. Gilca, A. C. Tricco, J. Ochnio and D. W. Scheifele, “Seroprevalence of Hep- atitis A, Infection in a Low Endemicity Country: A Sys- tematic Review,” BMC Infectious Diseases, Vol. 5, 2005, p. 56. doi:10.1186/1471-2334-5-56

[16]   K. Van Herck, P. Van Damme, F. Castelli, J. Zuckerman, H. Nothdurft, A. L. Dahlgren, S. Gisler, R. Steffen, P. Gargalianos, R. Lopéz-Vélez, D. Overbosch, E. Caumes, E. Walker, “Knowledge, Attitudes and Practices in Travel- Related Infectious Diseases: The European Airport Survey,” Journal of Travel Medicine, Vol. 11, No. 1, 2004, pp. 3-8. doi:10.2310/7060.2004.13609

[17]   H. D. Nothdurft, A. La Dahlgren, E. A. Gallagher, H. Kollaritsch, D. Overbosch, M. L. Rummukainen, P. Rendi-Wagner, R. Steffen and P. Van Damme, “The Risk of Acquiring Hepatitis A and B among Travelers in Selected Eastern and Southern Europe and Non-European Mediterranean Countries: Review and Consensus Statement on Hepatitis A and B Vaccination,” Journal of Travel Medicine, Vol. 14, No. 3, 2007, pp. 181-187. doi:10.1111/j.1708-8305.2007.00123.x

[18]   B. Genton, V. D’Acremont, H. J. Furrer, C. Hatz and L. Loutan, “Hepatitis A Vaccines and the Elderly,” Travel Medicine and Infectious Disease, Vol. 4, No. 6, 2006, pp. 303-312. doi:10.1016/j.tmaid.2005.10.002

[19]   N. Vatev, M. Atanasova, J. Stoilova, T. Chervenyakova and M. Troyancheva, “Seroprevalence of Hepatitis A Viral Infection in Plovdiv, Bulgaria,” Folia Medica, Vol. 1, 2009, pp. 70-73.

[20]   M. Kojouharova and Editorial Team, “Current Outbreak of Hepatitis A in Bulgaria, 2006,” European Surveillance, Vol. 11, No. 40, 2006, pp. 30-49.