ABSTRACT
Objectives@#This study aimed to investigate differences in the anti-hepatitis A (HAV) antibody seropositivity rate by age and gender. @*Methods@#We collected information on anti-HAV immunoglobulin G and immunoglobulin M status from samples submitted for HAV antibody testing in 2012–2022. A total of 1,333,615 cases were included in the analysis. @*Results@#By age, the seropositivity rate was represented by a U-shaped curve, such that the rate was low for the group aged 20 to 39 years and higher in those who were younger or older. Over time, the curve shifted rightward, and the seropositivity rate declined gradually in the group aged 35 to 39 years and older. A gender-based difference in antibody seropositivity rate was especially noticeable in the group aged 20 to 29 years. This difference between genders widened in the participants’ early 20s—when men in the Republic of Korea enlist in the military—and the divergence continued subsequently for older individuals. @*Conclusion@#These results indicate a higher risk of severe infection among older individuals and a gender-based difference in seroprevalence. Therefore, it is necessary to implement policies to promote vaccination in adults.
ABSTRACT
OBJECTIVES: Despite the importance of human immunodefi-ciency virus(HIV) transmission through heterosexual contact, the features of heterosexual transmission has not been well studied in Korea. So we conducted a cross sectional study to determine the transmission rates in married couples and assess risk factors for male to female heterosexual transmission of HIV. METHODS: 169 HIV-infected males and their female sex partners were recruited from 1985 to June 1998. We examined female sex partners HIV infection status and interviewed male index partners and their female sex partners about demographic characteristics and sexual practices. We analysed heterosexual transmission rate by epidemiologic characteristics, disease status and sexual practices. And we assessed risk factors for HIV infection by univariate and multivariate analysis. RESULTS: 30 female sex partners were infected at enrollment, yielding an transmission rate of 17.8%. Among couples who had used condoms consistently, none of the female sex partners was infected with HIV. In univariate analysis the significant risk factors were full blown AIDS status (OR=4.1, 95% CI: 1.49-11.43) and low CD4 T cell count of index partners at enrollment (OR=7.8, 95% CI: 2.19-27.80). In multivariate analysis HIV-1 RNA levels was significant risk factor when adjusted by CD4 T cell counts and mean sexual contacts per month (OR=19.2, 95% CI: 1.03-357.59) CONCLUSION: The risk of male to female heterosexual transmission increased with advanced stages of HIV infection in the index male partners.