in practical activity

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1 Measles: the vaccine efficacy in practical activity Irina Brumboiu 1*, Bocşan IS 1, Daniela Lăpuşan 1, Giorgiana Hâţu 1, Ligia Ursu 2, Daniela Petruş 2 1 The Iuliu Hatieganu University of Medicine and Pharmacy Epidemiology & Primary 1 The Iuliu Hatieganu University of Medicine and Pharmacy, Epidemiology & Primary Health Care Department, Cluj Napoca, Romania; *irinabrumboiu@yahoo.com 2 The Academic Infectious Diseases Hospital Cluj Napoca, Romania

2 Background Despite of the large scale measles vaccination programs, measles has still an epidemic evolution more often than expected (1, 2). In Romania, measles vaccination program was introduced in May 1979, and incidence dropped promptly to a very low level (fig.1) (3, 4). Since then, several epidemics have evolved in our vaccinated population; lti the last one started t quite recently (fig.2). In previous epidemics the proportion of cases with vaccination history has been growing (fig. 3) (4). (1)***Measles outbreaks in Europe, WER, 2011, 86(18): (2)*** Measles Progress towards global and regional elimination, ; WER, 1999, 74, (3) Brumboiu I: Vaccinarea antirujeolica. In Irina Brumboiu, I.S. Bocsan: Vaccinuri si vaccinari in practica medicala; Ed. Iuliu Hatieganu, Cluj-Napoca, 2005, (4) Brumboiu I.: Rujeola. În: Epidemiologie practică pentru medicii de familie, I. Bocşan, A. Rădulescu, I. Brumboiu et al.; Ed. Med. Univ. Iuliu Haţieganu, Cluj-Napoca, 1999,

3 Fig. 1: Measles evolution in Romania before and after measles vaccine implementation Source of data: Centre of Statistics of Ministry of Health, Romania; WHO..

4 Fig. 2: Measles epidemics in the vaccinated population of Romania, e for people Incidenc Source of data: WHO.

5 Fig. 3: Proportion of cases with history of vaccination in three previous measles outbreaks (5) Objective: to measure the efficacy of measles vaccination in three epidemics in Cluj County. (5) Irina Brumboiu, IS Bocsan, Ancuta Sava et al: Analiza dinamicii epidemiilor de rujeola in populatia vaccinata din zona de nord-vest a Romaniei, Clujul Medical, 2005, LXXVIII(1):

6 Methods Aiming to measure the efficacy of measles vaccine we conducted a case control study, for the epidemics of , and ; The data sources were the records of family doctors from Cluj County in both urban and rural areas; The target age group was 1 4 years; Controls were children registered at the same doctor, of same age ± one month; The vaccination history was searched in cases and controls ; Data base and statistics i in Excel.

7 Results 165 children for the epidemic, 589 for epidemic and 255 for measles epidemic seasons were included in thiscase case control control study; The vaccine efficacy for the three epidemics was: Item Case Control Case Control Case Control Vaccinated Unvaccinated Odds vaccinated 2,6:1 9.5:1 4,6:1 18,1:1 5,4:1 49,7:1 Odds Ratio 0,28 0,25 0,11 Vaccine efficacy % 72,2 74,6 89,1 IC95% 30,8 88,9 54,9 85,7 61,4 96,9 p <0,01 <0,001 <0,001

8 Discussions We analysed these three epidemics because the medical records were filled in similarly; starting the year 2000 the measles national surveillance program changed. The analysed target group was chosen as being the most vulnerable to severe clinicalforms of disease. The observed values of measles vaccine efficacy (in our study) are lower than real, because of the nature of case control study and the use of medical records for data collection. The assessment of field vaccine efficacy explores both the potential clinical efficacy of vaccine and the entire vaccination program as well (6). (6) Orenstein W., Bernier R., Hinman A.: Assessing vaccine efficacy in the field; Epidemiol. Rev., 1988, 10,

9 Conclusions In the day by day routine practice, the measles vaccine efficacy remains high in the most vulnerable age group (1 4 years of age), and stays the most important component of the measles elimination program. The continuous passive surveillance of measlesvaccine efficiency is an essential tool of long term measles control strategy.

10 Bibliography (1)***Measles outbreaks in Europe, WER, 2011, 86(18): 8) (2)*** Measles Progress towards global and regional elimination, ; WER, 1999, 74, (3) Brumboiu I: Vaccinarea antirujeolica. In Irina Brumboiu, I.S. Bocsan: Vaccinuri si vaccinari in practica medicala; Ed. Iuliu Hatieganu, Cluj Napoca, 2005, (4) Brumboiu I.: Rujeola. În: Epidemiologie practică pentru medicii de familie, I. Bocşan, A. Rădulescu, I. Brumboiu et al.; Ed. Med. Univ. Iuliu Haţieganu, Cluj Napoca, 1999, (5) Irina Brumboiu, IS Bocsan, Ancuta Sava, Ligia Ursu, Octavia Olariu, Ionela Pastina, Laura Simionca: Analiza dinamicii epidemiilor de rujeola in populatia vaccinata din zona de nord vest a Romaniei, Clujul Medical, 2005, LXXVIII(1): (6) Orenstein W., Bernier R.,Hinman A.: Assessing vaccine efficacy in the field; Epidemiol. Rev., 1988, 10,