Defining the immunity status of hepatitis B among health care workers of Mongolia

Abstract

Background: Healthcare workers have a high risk of viral hepatitis due to occupational exposure. The rates of HBsAg (+) 0.1%-8.1% and anti-HBc (+) 6.2%-73.4%, anti-HCV (+) 0.1%-9.7% in healthcare workers reported in several studies published, depending on their country of origin. Immunization of healthcare workers against hepatitis B virus (HBV) to prevent infection, and determine the immunity of the vaccine by determining the level of anti-HBV and whether to booster doses. Aim: To study the prevalence of hepatitis B and Delta viruses and immunity of hepatitis B among health workers at the national level. Materials and Methods: This is a cross-sectional study, a multi-stage random sampling, conducted 1135 health care workers from all level health facilities in Ulaanbaatar city and 5 provinces. Questionnaires and blood samples are taken from participants. Blood samples were analyzed HBsAg, anti-HDV, anti-HBc, anti-HBs using ELISA. Data was analyzed by using SPSS-23 program. Results: The few 4.7% (53/1135) of the study subjects was tested as HBsAg positive, while 7.8% (88/1135) were uninfected and non-immune. The most of them or 53.8% (611/1135) had post-infection immunity, and 33.7% (382/1135) had post-vaccination immunity. 22.64% (12/53) of HBsAg-positive participants were positive for anti-HDV. Anti-HBs titer level for the subjects with post-vaccination immunity were adequate or protective in 57.6% (220/382) of 100-999.99 IU/ ml, while 32.2% was weakly positive in 10-99.9IU/ml. The insufÏcient level was detected for 8.1% of the participants in 0 -9.9 IU/ml. The mean value is 176.80 [140.26-221.70] IU/ml. Conclusions: 1. HBV prevalence among the healthcare workers is 4.7%, and 22.64% of the participants with HBV had co-infection of hepatitis delta virus. 2. The proportion of health care workers with post-infection immunity rises with each year of service and older age, while the proportion of the ones with vaccine immunity improves with younger age and fewer working years, those phenomenon has increased statistical probability. 33.7% of total participants had post-vaccination immunity, and anti-HBs titer level for the subjects with post-vaccination immunity were protective in 59.7% of >100 IU/ml.