Department of Epidemiological Surveillance and Intervention

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1 EPIDEMIOLOGICAL DATA FOR ΤYPHOID/PARATYPHOID FEVER IN GREECE, MANDATORY NOTIFICATION SYSTEM NATIONAL REFERENCE CENTRE FOR SALMONELLA AND SHIGELLA Main points The notification rate for typhoid/paratyphoid fever in Greece is low. Based on data for the period: - Sixty six (42%) of the confirmed cases had traveled abroad during the incubation period - Travel-related cases were mainly foreigners who had traveled to their home country (VFRs, Visiting Friends or Relatives) - A seasonal pattern was apparent: the mean monthly notification rate reached a peak in August. Typhoid fever is a systematic disease, caused by Salmonella Τyphi. The incubation period of the disease is 3-40 days. Paratyphoid fever is also a systematic disease, with an incubation period of 7-10 days. It is caused by Salmonella Paratyphi, for which three types have been identified: A, B and C [1]. Humans get infected after consuming contaminated food or water. Two to 5% of the cases become chronic carriers. Chronic carriage is more frequent among S. Typhi cases than it is among S. Paratyphi B cases. Paratyphi A and C have only short-term carriers. Time trend The number of notified cases for the period , is shown in Table 1. Out of the 167 reported cases, 90 (53.9%) were typhoid and 77 (46.1%) were paratyphoid cases. Time trend of the typhoid/paratyphoid fever notification rate is depicted in Graph 1. 1

2 The annual notification rate for typhoid/paratyphoid fever for the period , ranged from 0.4 cases in 2009 to 1.8 cases per 1,000,000 population in 2004 and The mean annual notification rate for typhoid/paratyphoid fever for the same period was 1.1 cases per 1,000,000 population, and the mean annual number of reported cases was 10.5 (standard deviation: 5.38). Notification rates of typhoid and paratyphoid fever were 0.6 and 0.5 cases per 1,000,000, respectively (median number of typhoid cases: 5, min:3-max:15, median number of paratyphoid cases: 4.5, min:0-max:14). Age and gender distribution Typhoid/paratyphoid fever is more common among children. In particular, for the period, the disease had a higher mean annual notification rate in the age group 0-4 years (4.1 cases per 1,000,000 population), followed by the age group of 5-14 years (1.9 cases per 1,000,000 population) (Graph 2). The mean annual notification rate for typhoid/paratyphoid fever for the same period was 1.4 cases/1,000,000 in males and 0.7/1,000,000 in females. As shown in Table 2, age and gender distribution differed between Greeks and foreigners (nationality other than Greek). The majority of foreigners (85.7%) were males and 55.3% of them were between 25 and 44 years old. Seasonality The mean monthly notification rate for the period increased during summer and autumn, reaching a peak in August (Graph 3). Geographical distribution The geographical area of Epirus had the highest mean annual notification rate for (2.3 cases per 1,000,000 population), and the area of Peloponnesos the lowest with 0.2 cases per 1,000,000 population. Laboratory data All notified cases during this period were laboratory-confirmed. S. Paratyphi type A was identified in 36 out of the 62 cases (58.1%) that the respective information was known and S. Paratyphi type B in 26 (41.9%). 2

3 It should be noted that the presented data here regard the cases reported via the mandatory notification system. For some of them the respective information from the reference laboratory is available while for others it is not. Data on the total number of isolates serotyped at the Reference Laboratory can be found at: Risk factors Seventy seven (47%) of the laboratory-confirmed cases that were notified during were of foreign origin. Sixty six (41.8%) of the reported cases, had traveled abroad during incubation period; nine Greeks and 56 foreigners (Table 3). Traveling abroad mainly regarded migrants, who had traveled to their country of origin prior to disease onset (VFRs, Visiting Friends or Relatives) (82.7%). Fourteen (8.7%) cases reported the presence of another person with similar symptoms among their contacts. Discussion Typhoid and paratyphoid fever present low notification rates in Greece. The mean annual notification rate for was lower than that reported by the EU and EEA/EFTA countries (3.1 cases/1,000,000 population for the year 2014) [2]. When interpreting this difference, the surveillance systems probable under-reporting should be taken into account. The high proportion of imported cases is consistent with data reported by other European countries [3-5]. The difference between Greeks and foreigners regarding the age and gender distribution is in agreement with the fact that the majority of the economical migrants in the country are young adult men. References 1. Heymann D, MD. Control of Communicable Diseases Manual. 20th Edition, 2015, American Public Health Association. 2. European Centre for Disease Prevention and Control. Surveillance Atlas of Infectious Diseases. Typhoid and paratyphoid fever - Data by Country and Year. Current time period: Available from: 3. Clark TW, Daneshvar C, Pareek M, Perera N, Stephenson I. Enteric fever in a UK regional infectious diseases unit: a 10 year retrospective review. J Infect. 2010;60(2):

4 4. Gil R, Alvarez JL, Gomez C, Alvaro A, Gil A. Epidemiology of typhoid and paratyphoid fever hospitalizations in Spain ( ). Hum Vaccin. 2009;5(6): Keller A, Frey M, Schmid H, Steff en R, Walker T, Schlagenhauf P. Imported typhoid fever in Switzerland, 1993 to J Travel Μed. 2008;15(4): Table 1. Number of reported cases of typhoid/paratyphoid fever, Mandatory Notification System & National Reference Centre for Salmonella and Shigella, Greece, Number of cases Total Year Typhoid fever Paratyphoid fever Total

5 Mean incidence Cases/1,000,000 2,00 1,80 1,60 1,40 1,20 1,00 0,80 0,60 0,40 0,20 0, Year Graph 1. Time trend of typhoid/paratyphoid notification rate (number of cases/1,000,000 population) in Greece, Mandatory Notification System & National Reference Centre for Salmonella and Shigella, ,5 4,0 3,5 3,0 2,5 2,0 1,5 1,0 0,5 0, Age group (years) Graph 2. Mean notification rate of typhoid/paratyphoid fever (number of cases/1,000,000 population) in Greece by age group, Mandatory Notification System & National Reference Centre for Salmonella and Shigella, Table 2. Distribution of typhoid/paratyphoid fever cases by age and gender in Greeks and people of foreign nationality, Mandatory Notification System & National Reference Centre for Salmonella and Shigella, Greece, Greeks Foreigners Total 5

6 Cases/1,000,000 Gender Male 42 (48.8%) 66 (85.7%) 108 (65.8%) Female 44 (51.2%) 11 (14.3%) 55 (33.5%) Age group (years) (25.9%) 8 (10.5%) 30 (18.6%) (23.5%) 9 (11.8%) 29 (18.0%) (9.4%) 13 (17.1%) 21 (13.0%) (16.5%) 42 (55.3%) 56 (34.8%) (10.6%) 4 (5.3%) 13 (8.1%) (14.1%) 0 (0.0%) 12 (7.4%) *n = number of cases, %= percentage for the cases that the respective information was available 0,25 0,20 0,15 0,10 0,05 0,00 Month Graph 3. Mean notification rate of typhoid/paratyphoid fever (number of cases/1,000,000 population) by month, Mandatory Notification System & National Reference Centre for Salmonella and Shigella, Greece, Table 3. Distribution of travel-related typhoid/paratyphoid fever cases by country of destination among Greeks and people of foreign nationality, Mandatory Notification System & National Reference Centre for Salmonella and Shigella, Greece, Country Foreigners Greeks Pakistan 24 (46.1%) 1 (11.1%) India 13 (25.0%) 3 (33.3%) 6

7 Turkey 4 (7.7%) 0 (0.0%) Bangladesh 4 (7.7%) 0 (0.0%) Afghanistan 2 (3.8%) 0 (0.0%) Nigeria 1 (1.9%) 0 (0.0%) Nepal 1 (1.9%) 1 (11.1%) Panama 1 (1.9%) 0 (0.0%) Anguilla 1 (1.9%) 0 (0.0%) Israel 1 (1.9%) 0 (0.0%) Swaziland 0 (0.0%) 1 (11.1%) Bulgaria 0 (0.0%) 1 (11.1%) France 0 (0.0%) 1 (11.1%) Peru 0 (0.0%) 1 (11.1%) Total 52 (100.0%) 9 (100.0%) *n = number of cases, % = percentage Foodborne and Waterborne Diseases Unit K. Mellou, T. Sideroglou, E. Saranti-Papasaranti Tel: , National Reference Centre for Salmonella and Shigella G. Mandilara, A. Vatopoulos 7