The distribution of HBV infection among the world shows differences according to geography. Because of these differences HBsAg endemicity is classified as low if positivity is lower than or equal to 2%, moderate if between 2-10% and high if greater than 10%. According to this classification, the Bolu region is near the lower borderline of moderate endemicity (2.85%) (3). In our country HBsAg positivity is reported to be between 3.9% and 12.5%, varying in different regions of the country by ELISA method (6). These data show that our country is moderately endemic for HBsAg positivity and that there are 4 million carriers (1). The results of our study demonstrated an HBsAg positivity rate of 2.7%, which is lower than most of the other studies done in Turkey.
The possible reasons for this may be the increase in public consciousness of this disease with the help of the media. Another reason may be the more common usage of screening tests. Out of the 3,084 subjects screened, only 1,374 (44.5%) accepted to be tested for HBsAg positivity. This situation may be related to the following. First, subjects who may have been tested before and already found as positive for HbsAg may not have wanted to take part in the study for fear of their positivity being disclosed. Second, some subjects have a phobia against having their blood drawn. This may partially explain why our results were lower than actual positivity. Furthermore, Bolu was divided into local districts, and samples were collected by public survey in an effort to represent the whole population. Lastly, either professional blood donors or subjects attending Red Crescent Blood Banks comprised the study groups in most of the other studies. Most of the donors attending Red Crescent Blood Banks are soldiers, and the ones from eastern and southeastern regions of Turkey may have increased the seropositivity for HBsAg.
Brucellosis caused by Brucella spp occurs naturally in domestic animals and is transmitted to human beings mainly through ingestion of contaminated milk or milk products or by close contact with infected livestock or their tissues or secretions; it is endemic in certain parts of Turkey. It is still an important public health problem throughout the world, but principally, and in particular, in the Mediterranean region, including Turkey, the Arabian Peninsula, the Indian subcontinent, Mexico, and parts of Central and South America (7). In Turkey, approximately 15,000 cases of Brucella are reported annually according to the 2001 data of the Ministry of Health of Turkey. However, it is believed that the actual number of cases is at least 50,000-100,000 per year, if the unreported and subclinical cases are considered. For this reason, brucellosis is an important public health problem in our country (8), and it is crucial to detect its actual incidence in fighting against this disease (9). We found that the incidence of exposure to Brucella and acquisition of brucellosis in Bolu is 1% and 0.46%, respectively. However, the Ministry of Health of Turkey has reported this incidence as 0.0047%. This may be because the number of unreported or subclinical cases with brucellosis is quite high. The Brucella prevalence is higher than the data reported by the Ministry of Health. The significant difference between the data obtained may be a result of the unreliability of health records in our country. We believe that public health programs in Bolu should focus on educating the population about the risk of consuming dairy products made from unpasteurized milk, such as soft cheeses (10).
In conclusion, the prevalence of HBsAg seropositivity, Brucella antibodies seropositivity and of brucellosis were determined as 2.85%, 1% and 0.46%, respectively, in the central region of Bolu. No difference in Brucella and HBsAg carriage has been detected between urban and rural areas. HBsAg seropositivity in Bolu is lower than in many other centers in Turkey (11, 12). Brucella prevalence is 1%, which is higher than that in the records of the Ministry of Health. This shows that the recording system in our country is not very efficient. Similar studies should be carried out in different regions of our country to determine the actual values, and this requires the cooperation of scientific foundations and the Ministry of Health.
){kind=link}