Differences in seroprevalence between epicenter and non-epicenter areas of the COVID-19 outbreak in South Korea

Jeong Hye Won,Chang Hyun-Ha,Kim Eun Ji,Kim Yu Kyung,Kim Se-Mi,Kim Eun-Ha,Kim Young-Il,Casel Mark Anthony B.,Kim Seong-Gyu,Rollon Rare,Jang Seung-Gyu,유광민,Kim Hee-Sung,Park Hee Sue,Park Su-Jin,Kim Yong- 한국미생물학회 2021 The journal of microbiology Vol.59 No.5

To compare the standardized severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence of high epicenter region with non-epicenter region, serological studies were performed with a total of 3,268 sera from Daegu City and 3,981 sera from Chungbuk Province. Indirect immunofluorescence assay (IFA) for SARS-CoV-2 IgG results showed a high seroprevalence rate in the Daegu City (epicenter) compared with a non-epicenter area (Chungbuk Province) (1.27% vs. 0.91%, P = 0.0358). It is noteworthy that the highest seroprevalence in Daegu City was found in elderly patients (70’s) whereas young adult patients (20’s) in Chungbuk Province showed the highest seroprevalence. Neutralizing antibody (NAb) titers were found in three samples from Daegu City (3/3, 268, 0.09%) while none of the samples from Chungbuk Province were NAb positive. These results demonstrated that even following the large outbreak, the seropositive rate of SARS-CoV-2 in the general population remained low in South Korea.

Seroprevalence and risk factors of sheep and goat pox virus in selected districts of Wolaita Zone, Southern Ethiopia

Fentaye Kassa,Haben Fesseha,Mesfin Mathewos,Selenat Getachew,Nato Hundessa,Saliman Aliye,Isayas Asefa Kebede 대한수의학회 2024 Journal of Veterinary Science Vol.25 No.4

Importance: Sheep and goat pox (SGP) virus infection is a highly fatal viral infection of small ruminants that causes major production losses in sheep and goats in Ethiopia while also limiting international trade. Objective: This study aimed to estimate the seroprevalence of SGP infection and assess related risk variables. Methods: A cross-sectional study was conducted from February to August 2023 on 384 serum samples taken from sheep and goats. A serum neutralization test was conducted to detect the presence of antibodies against the SGP virus in Wolaita Sodo Regional Laboratory. Results: The overall seroprevalence rate of SGP was 4.95%. Factors such as sheep (8.26%), female sheep and goats (7.45%), older sheep and goats (8.33%), larger flock size of sheep and goats (10.47%), poorly conditioned sheep and goats (31.58%), sheep and goats with a tick on their skin (10.38%), and animals that had not been vaccinated (5.17%) were found to have higher seroprevalence. Furthermore, the seropositivity in sheep was five times greater than in goats (adjusted odds ratio [AOR], 4.73; 95% confidence interval [CI], 1.39–15.99). Additionally, large-sized flocks of sheep and goats were more likely to be seropositive to pox disease than small-sized flocks (AOR, 6.73; 95% CI, 1.58–28.67). Conclusions and Relevance: Thus, the study revealed the prevalence of SGP in the Wolaita zone. Additional research should be conducted to estimate the extent of the disease at the regional level, and management measures should be implemented to reduce the economic losses associated with this condition.

Serological studies on murine typhus in field workers of national forest

( Byoungchul Gill ),( Hyun-sul Lim ),( Ji-hyuk Park ),( Jeongmin Lee ),( Nari Shin ),( Yeong Seon Lee ) 대한인수공통전염병학회 2017 창립총회 및 학술대회 초록집 Vol.2017 No.1

Background: Rickettsia species are gram negative, strictly intracellular bacilli that multiply within the cytosol endothelial cells. Rickttsia typhi, a typhus group rickettsia, is the etiologic agent of murine or endemic typhus. R. typhi is transmitted to human primarily by the rat flea, Xenopsylla cheopis, although lice and mites are also potential vectors. In Korea, about 50 cases of this disease has been reported since the first case reported in the 1950s. This surveillance study was conducted to obtain basic data of murine typhus for prevention and control in high-risk population. Materials and Methods: This study included field workers (Yeongrim-dan) in national forest considered as a high-risk population of scrub typhus. The eligible participants were 715 (43.9%) out of 1,629 forestry workers. The sera were collected and then the antibodies specific to R. typhi Wilmington causing murine typhus were titrated using indirect immunofluorescence antibody assay (IFA). As a reference for seroprevalence, 1:256 in IgG or 1:16 in IgM was considered as a single cut-off titer. Results: The seroprevalence showing higher titration than the single cut-off and seroreactivity showing any titration to the single cut-off were 12.4% (89/715) and 26.5% (190/715), respectively. However, the gene for the 16s rRNA of Rickettsia spp. was not detected in any seroprevalence-positive samples. Conclusion: This is the first serological study of murine typhus among forestry workers considered as high-risk population. The high exposure to R. typhi amongst forestry workers suggests that flea-borne spotted fever is an important cause of undifferentiated fever conditions that may not be adequately recognized in Korea. Therefore, continuous surveillance needs to understand the status and to improve the control and prevention of these diseases in high-risk population.

Changes in age-specific seroprevalence of Japanese encephalitis virus and impact of Japanese encephalitis vaccine in Korea

Kwak Byung Ok,Hong Young Jin,Kim Dong Hyun 대한소아청소년과학회 2022 Clinical and Experimental Pediatrics (CEP) Vol.65 No.3

The Japanese encephalitis (JE) virus is the leading cause of vaccine-preventable encephalitis in Asia. Since the introduction of a universal JE vaccination program and urbanization of Korea, the incidence of JE has dramatically decreased in Korea. However, recent JE cases have occurred, predominantly among unvaccinated adults and with a shift in age distribution. Here we aimed to review the changes in age-specific JE seroprevalence over time and discuss the implications of JE vaccination programs in Korea. Following the last epidemic in 1982?1983, mandatory vaccination for all children aged 3?15 years was conducted annually until 1994. However, JE has reemerged, predominantly affecting unvaccinated adults aged 40 years or older and demonstrating a shift in age distribution toward older populations. The age-specific seroprevalence of the JE virus in Korea has changed noticeably over time. Seropositivity in children and adolescents increased from 10%?59% in the 1970s to 90%?92% in the 1980s after the implementation of the JE vaccination program and increased further to 98% in 2012. No age-specific difference in the seroprevalence of JE was found, and appropriate levels of immunity to JE were maintained for all age groups. Continuous surveillance of the seroprevalence of JE is essential to establish a proper immunization policy in Korea. The Japanese encephalitis (JE) virus is the leading cause of vaccine-preventable encephalitis in Asia. Since the introduction of a universal JE vaccination program and urbanization of Korea, the incidence of JE has dramatically decreased in Korea. However, recent JE cases have occurred, predominantly among unvaccinated adults and with a shift in age distribution. Here we aimed to review the changes in age-specific JE seroprevalence over time and discuss the implications of JE vaccination programs in Korea. Following the last epidemic in 1982–1983, mandatory vaccination for all children aged 3–15 years was conducted annually until 1994. However, JE has reemerged, predominantly affecting unvaccinated adults aged 40 years or older and demonstrating a shift in age distribution toward older populations. The age-specific seroprevalence of the JE virus in Korea has changed noticeably over time. Seropositivity in children and adolescents increased from 10%–59% in the 1970s to 90%–92% in the 1980s after the implementation of the JE vaccination program and increased further to 98% in 2012. No age-specific difference in the seroprevalence of JE was found, and appropriate levels of immunity to JE were maintained for all age groups. Continuous surveillance of the seroprevalence of JE is essential to establish a proper immunization policy in Korea.

Original Article : Changes in the seroprevalence of IgG anti-hepatitis A virus between 2001 and 2013: experience at a single center in Korea

( Sung Jun Chung ),( Tae Yeob Kim ),( Sun Min Kim ),( Min Roh ),( Mi Yeon Yu ),( Jung Hoon Lee ),( Chang Kyo Oh ),( Eun Young Lee ),( Seung Lee ),( Yong Cheol Jeon ),( Kyo Sang Yoo ),( Joo Hyun Sohn ) 대한간학회 2014 Clinical and Molecular Hepatology(대한간학회지) Vol.20 No.2

Background/Aims: The incidence of symptomatic hepatitis A reportedly increased among 20- to 40-year-old Korean during the late 2000s. Vaccination against hepatitis A was commenced in the late 1990s and was extended to children aged <10 years. In the present study we analyzed the changes in the seroprevalence of IgG anti-hepatitis A virus (HAV) over the past 13 years. Methods: Overall, 4903 subjects who visited our hospital between January 2001 and December 2013 were studied. The seroprevalence of IgG anti-HAV was analyzed according to age and sex. In addition, the seroprevalence of IgG anti-HAV was compared among 12 age groups and among the following time periods: early 2000s (2001-2003), midto- late 2000s (2006-2008), and early 2010s (2011-2013). The chi-square test for trend was used for statistical analysis. Results: The seroprevalence of IgG anti-HAV did not differ significantly between the sexes. Furthermore, compared to the seroprevalence of IgG anti-HAV in the early 2000s and mid-to-late 2000s, that in the early 2010s was markedly increased among individuals aged 1-14 years and decreased among those aged 25-44 years (P<0.01). We also found that the seroprevalence of IgG anti-HAV in individuals aged 25-44 years in the early 2010s was lower than that in the early 2000s and mid-to-late 2000s. Conclusions: The number of symptomatic HAV infection cases in Korea is decreasing, but the seroprevalence of IgG anti-HAV is low in the active population. (Clin Mol Hepatol 2014;20:162-167)

경북지역 집합유와 젖소에서 큐열 항체 보유율 조사

우인옥 ( In Ohk Ouh ),서민구 ( Min Goo Seo ),도재철 ( Jae Cheul Do ),김인경 ( In Kyoung Kim ),조민희 ( Min Hee Cho ),곽동미 ( Dong Mi Kwak ) 한국동물위생학회 2013 한국동물위생학회지 (KOJVS) Vol.36 No.4

Q fever is a rickettsial infection caused by Coxiella burnetii that is transmitted from animals to humans. Modes of transmission to humans include inhalation, tick bites and ingestion of unpasteurized milk or dairy products. This survey was aimed at monitoring the seroprevalence of C. burnetii in bulk-tank milk (BTM) in Gyeongbuk province. In addition, the seroprevalence of C. burnetii was investigated at the herd level of dairy cattle in eastern Gyeongbuk province in which many dairy cattle are reared. Among 324 BTM samples collected from 20 country areas, 175 (54%) BTM samples from 15 (75%) country areas were positive for C. burnetii by ELISA. By regions, the seroprevalence of BTM samples in eastern, central, western and northern areas of Gyeongbuk province were 62.7%, 48.4%, 45.1%, and 41.4%, respectively. When analyzed in the dairy cattle reared in the eastern area where high seroprevalence occurred in BTM samples, 119 (24.2%) out of 492 dairy cattle were positive for C. burnetii. Seroprevalence of C. burnetii in dairy cattle was increased with daily milk yield of farm (P<0.05) and age (P<0.001). Since seroprevalence of C. burnetii is relatively high in both BTM samples and dairy cattle reared in Gyeongbuk province, further studies on the high risk farms and herds are needed to evaluate infection status and appropriate control programs in this region.

Seroprevalence of Antibody to Hepatitis A Virus in North-West Jeonbuk Province

( Yong Sub Shin ),( Yoo Hyun Kim ) 대한임상검사과학회 2013 대한임상검사과학회지(KJCLS) Vol.45 No.3

Hepatitis A (HA) is an acute infectious disease of the liver caused by the Hepatitis A virus (HAV). In acute HA, the presence of anti-HAV IgM is detectable and about 3 weeks after exposure, its titre increases over 4 to 6 weeks. Anti-HAV IgG is detectable within a few days of the onset of symptoms. IgG antibodies continue to last for years after infection and provide lifelong immunity to the host. This study was performed to investigate the current seroprevalence of anti-HAV antibodies in Jeonbuk province, South Korea. A total of 591 (male 322, female 269) serum samples were collected in July 2011 to June 2012. We tested the antibodies of anti-HAV IgG and IgM using a Modular E170 (Roche Diagnostics, Germany), and analysed the serum alanine aminotransferase (ALT) levels by HITACH 7600-100 (HITACH, Japan). The overall seroprevalence of anti-HAV IgG was 84.6% (500/591), and the rate of females (85.9%) was higher than males (83.5%). According to the decade of age, seroprevalence of anti-HAV IgG were as follows; 68.8% (11/16) in the under 10 years old category, 100% (19/19) in the 10∼19 category, 96% (48/50) in the 20∼29 category, 83.6% (56/67) in the 30∼39 category, 84.3% (123/146) in the 40∼49 category, 83.3% (135/162) in the 50∼59 category, 83.1% (54/65) in the 60∼69 category, 78.1% (32/41) in the 70 ∼79 category, and 88% (22/25) in the over 80 category. Total seroprevalence of anti-HAV IgM was 3.4% (20/591), and according to gender, the seroprevalence of male (3.1%) was very similar to that of female (3.7%). Through this study, we know that the seroprevalence of anti-HAV antibody in north-west Jeonbuk province, South Korea, was high. Only children under the age of 10 remain susceptible to HAV infection. Vaccination against HAV is not needed at the present time for the people of Jeonbuk province, South Korea, but a vaccination should be recommended and the improvement in sanitary conditions and personal hygiene should be highlighted.

Seroprevalence of Antibody to Hepatitis A Virus in North-West Jeonbuk Province

Shin, Yong Sub,Kim, Yoo Hyun 대한임상검사과학회 2013 대한임상검사과학회지(KJCLS) Vol.45 No.3

Hepatitis A (HA) is an acute infectious disease of the liver caused by the Hepatitis A virus (HAV). In acute HA, the presence of anti-HAV IgM is detectable and about 3 weeks after exposure, its titre increases over 4 to 6 weeks. Anti-HAV IgG is detectable within a few days of the onset of symptoms. IgG antibodies continue to last for years after infection and provide lifelong immunity to the host. This study was performed to investigate the current seroprevalence of anti-HAV antibodies in Jeonbuk province, South Korea. A total of 591 (male 322, female 269) serum samples were collected in July 2011 to June 2012. We tested the antibodies of anti-HAV IgG and IgM using a Modular E170 (Roche Diagnostics, Germany), and analysed the serum alanine aminotransferase (ALT) levels by HITACH 7600-100 (HITACH, Japan). The overall seroprevalence of anti-HAV IgG was 84.6% (500/591), and the rate of females (85.9%) was higher than males (83.5%). According to the decade of age, seroprevalence of anti-HAV IgG were as follows; 68.8% (11/16) in the under 10 years old category, 100% (19/19) in the 10~19 category, 96% (48/50) in the 20~29 category, 83.6% (56/67) in the 30~39 category, 84.3% (123/146) in the 40~49 category, 83.3% (135/162) in the 50~59 category, 83.1% (54/65) in the 60~69 category, 78.1% (32/41) in the 70~79 category, and 88% (22/25) in the over 80 category. Total seroprevalence of anti-HAV IgM was 3.4% (20/591), and according to gender, the seroprevalence of male (3.1%) was very similar to that of female (3.7%). Through this study, we know that the seroprevalence of anti-HAV antibody in north-west Jeonbuk province, South Korea, was high. Only children under the age of 10 remain susceptible to HAV infection. Vaccination against HAV is not needed at the present time for the people of Jeonbuk province, South Korea, but a vaccination should be recommended and the improvement in sanitary conditions and personal hygiene should be highlighted.

전북지방의 북서부에 A형 간염 바이러스에 대한 항체의 양성률

신용섭,김유현 대한임상검사과학회 2013 대한임상검사과학회지(KJCLS) Vol.45 No.3

Hepatitis A (HA) is an acute infectious disease of the liver caused by the Hepatitis A virus (HAV). In acute HA, the presence of anti-HAV IgM is detectable and about 3 weeks after exposure, its titre increases over 4 to 6 weeks. Anti-HAV IgG is detectable within a few days of the onset of symptoms. IgG antibodies continue to last for years after infection and provide lifelong immunity to the host. This study was performed to investigate the current seroprevalence of anti-HAV antibodies in Jeonbuk province, South Korea. A total of 591 (male 322, female 269) serum samples were collected in July 2011 to June 2012. We tested the antibodies of anti-HAV IgG and IgM using a Modular E170 (Roche Diagnostics, Germany), and analysed the serum alanine aminotransferase (ALT) levels by HITACH 7600-100 (HITACH, Japan). The overall seroprevalence of anti-HAV IgG was 84.6% (500/591), and the rate of females (85.9%) was higher than males (83.5%). According to the decade of age, seroprevalence of anti-HAV IgG were as follows; 68.8% (11/16) in the under 10 years old category, 100% (19/19) in the 10∼19 category, 96% (48/50) in the 20∼29 category, 83.6% (56/67) in the 30∼39 category, 84.3% (123/146) in the 40∼49 category, 83.3% (135/162) in the 50∼59 category, 83.1% (54/65) in the 60∼69 category, 78.1% (32/41) in the 70 ∼79 category, and 88% (22/25) in the over 80 category. Total seroprevalence of anti-HAV IgM was 3.4% (20/591), and according to gender, the seroprevalence of male (3.1%) was very similar to that of female (3.7%). Through this study, we know that the seroprevalence of anti-HAV antibody in north-west Jeonbuk province, South Korea, was high. Only children under the age of 10 remain susceptible to HAV infection. Vaccination against HAV is not needed at the present time for the people of Jeonbuk province, South Korea, but a vaccination should be recommended and the improvement in sanitary conditions and personal hygiene should be highlighted.

국내 의료종사자에서 HHV-8의 항체양성률에 대한 연구

주우철,최용준,박재은,이혜명,이진수,정문현,김수미,문지혜 대한감염학회 2008 Infection and Chemotherapy Vol.40 No.4

HHV-8 virus is known to be associated with Kaposi's sarcoma (KS) in HIV seropositive patients and its seroprevalence has geographic difference. In South Korea, incidence of KS is low not only in general population but also in HIV patients compared to other countries. It is speculated that low seroprevalence of HHV-8 has contributed to the low incidence of KS in South Korea. We examined the seroprevalence of anti HHV-8 IgG of HIV seronegative health care workers in one University hospital. Enzyme-linked immunosorbent assay(ELISA) was used for diagnosis. One person (0.6%,1/164) was seropositive, six were equivocal (3.7%,6/164) and 157 people were seronegative (95.73%,157/164). This study revealed that seroprevalence of HHV-8 in general population was low in South Korea. Further studies are needed to be carried out to evaluate the low HHV-8 seroprevalence in Korea.