Infection rates of Enterobius vermicularis and Clonorchis sinensis of primary school children in Hamyang-gun, Gyeongsangnam-do (province), Korea

Enterobius vermicularis Infection among Preschool Children: A 12-Year (2008-2019) Survey in Large Cities and Provinces of the Republic of Korea

A 12-year nationwide survey (2008-2019) was performed to investigate the prevalence of Enterobius vermicularis infection among preschool children in Seoul, 4 large cites (Busan, Incheon, Daegu, and Ulsan), and 9 provinces (grouped into 5 localities) in the Republic of Korea (=Korea). The survey was carried out once a year by 16 regional offices of the Korea Association of Health Promotion. The cello-tape perianal swab method (1 smear per child) was applied to detect eggs of E. vermicularis and other helminths. According to the results, the egg positive rate of E. vermicularis infection in 2008-2009 was 1.8-2.0%, but it decreased gradually to 0.6% in 2019 (P<0.05). The prevalence was significantly higher in boys (0.7-5.0%, mean 1.8%) than in girls (0.5-2.8%, mean 1.3%) (P<0.05). The 2 most southern localities, Jejudo (Province) and Jeolla-do (inclusive of Jeollabuk-do and Jeollanam-do) and a mid-western province, Gyeonggi-do, revealed higher prevalences, whereas Seoul and Gangwon-do showed lower prevalences. The results indicate that a low-grade prevalence of E. vermicularis infection (less than 4%) has been maintained for the recent 12 years among preschool children in Korea. Continuous monitoring of enterobiasis in the child age group is necessary in Korea.

A preliminary epidemiological study of pinworm infection in Thaklong Municipal Early Childhood Development Center and Rangsit Babies' Home, Pathum Thani, Thailand

Objectives

We investigated the prevalence and risk factors for Enterobius vermicularis in children at the Thaklong Municipal Early Childhood Development Center (TMECDC), and the Rangsit Babies’ Home (RBH) in Pathum Thani, Thailand using the Scotch tape method.

Results

397 children aged 3–6 years were sampled (male = 198); 31 (7.8%) were E. vermicularis positive: 1 (TMECDC) and 30 (RBH). 264/397 (66.50%) of parents had incomes > 12,000 baht/month and 313/397 (78.84%) were educated from primary school to college. Univariate analysis identified (i) age 5–6 years, (ii) female sex, (iii) lower education of mother/father, (iv) being a house wife, (v) being a low income family, (vi) being resident in the orphanage, (vii) reporting anorexia and/or fever, and (viii) not washing their bottoms as factors for a positive slide. By logistic regression, education level and age group were independently associated with a positive Scotch tape result. Older children and higher family education had opposing associations with E. vermicularis. Strategies to control pinworm infection should focus on high-risk children in orphanages.

Parents' knowledge about enterobiasis might be one of the most important risk factors for enterobiasis in children

To know the prevalence of Enterobius vermicularis infection and what are the most important risk factors, we evaluated the incidence and risk factors of enterobiasis among children attended in kindergartens in Busan metropolitan city, Republic of Korea. A total of 1,674 children from 21 kindergartens in 11 of 16 autonomous districts of Busan were evaluated for E. vermicularis infection by the cellotape anal swab technique. The overall egg-positive rate for E. vermicularis was 10.7% (179/1,674), and the prevalence of enterobiasis in each kindergarten ranged between 0% and 32.4%. There was an increasing tendency of the egg positive rate according to the population density; the higher the population density communities had, the higher egg-positive rate for E. vermicularis was detected (P = 0.001). Among personal hygiene factors involving children, thumb-sucking (P = 0.036) and fingernail-trimming (P = 0.024) were highly associated with enterobiasis. In addition, taking anthelmintic medications against E. vermicularis infection was strongly associated with enterobiasis (P = 0.014). Moreover, parents' knowledge of enterobiasis was correlated significantly with the incidence of enterobiasis of their children (P = 0.006). In conclusion, we need to consider not only personal hygiene but also parents' knowledge about enterobiasis as a factor in order to develop new strategies for elimination or to complete reduction of enterobiasis in Korea.

Egg positive rate of Enterobius vermicularis among preschool children in Cheongju, Chungcheongbuk-do, Korea

In an attempt to determine the prevalence of pinworm infection, the egg positive rate of Enterobius vermicularis was examined using the adhesive cello-tape anal swab method in 1,512 preschool children sampled from a total of 20 kindergartens in Cheongju city, in November to December of 2004 (951 children from 13 kindergartens) and September to October of 2005 (561 from 7 kindergartens). The overall egg positive rate was found to be 7.9% (119/1,512); 9.3% (73/784) for boys and 6.3% (46/728) for girls, respectively. The 5-year age group evidenced the highest egg positive rate (10.9%, 47/430) among the examined age groups. As compared to those reported from previous works (ranged from 9.2 to 26.1%), the prevalence of E. vermicularis in the Cheongju city area is relatively low.

A bile based study of Clonorchis sinensis infections in patients with biliary tract diseases in Ulsan, Korea

Stool examination is believed to be the most reliable method for detecting Clonorchis sinensis (CS) eggs. However, it has limited value for diagnosing clonorchiasis when the biliary tract is obstructed or when there is a light infection. We evaluated the infection states of CS in patients with biliary tract diseases using a bile sample. From January 2001 to August 2003, 238 patients who had undergone endoscopic biliary drainage were prospectively included in the study. The patients' bile samples were obtained directly from the nasobiliary drainage tube and then analyzed to detect CS eggs. The overall CS egg positive rate was 28.2% (35.4% in males, 19.4% in females). The egg positive rate was similar in all age groups examined: 26.7% in 30-39 years, 25.0% in 40-49 years, 24.4% in 50-59 years, 30.2% in 60-69 years, 35.3% in 70-79 years, and 25.0% in 80 years of age and over. There were no significant differences in the egg positive rate between the disease groups: 32.6% in bile duct cancer, 38.5% in gallbladder cancer, and 26.4% in gallstone diseases. Our results show that the CS infection rate was very high, regardless of the age, gender, and type of diseases of the patients. Although the study population was limited to patients with biliary tract diseases, it is assumed that clonorchiasis is still an endemic disease in Ulsan, Korea.

Enterobius vermicularis infection among population of General Mansilla, Argentina

AIM: To evaluate the relationships between the personal, sociocultural, and environmental characteristics, and the presence or absence of symptoms with the detection of Enterobius vermicularis (E. vermicularis) in a population sample in our region (General Mansilla, Province of Buenos Aires, Argentina), by individual and familiar analyses.

METHODS: E. vermicularis was diagnosed in 309 people from 70 family units residing in the urban area and the rural area of the city of General Mansilla. Each of them was surveyed so as to register personal, environmental and sociocultural data. Questions about the presence or absence of anal itch, abdominal pain and sleeping disorder were also asked. Significant associations were determined by square chi tests. Logistic regression models were adjusted by using a backward conditional stepwise method to determine the presence of this parasite in the individuals and in the families.

RESULTS: The parasites were found in 29.12% (90/309) of the individuals, with a frequency of 14.28% (20/140) among the heads of the families and of 41.42% (70/169) among the children. The only variables showing a significant association were affiliation, where the risk category was "being the son/daughter of", and the symptoms were abdominal pain, sleeping disorder, and anal itch. Families with a member infected with parasite were considered Positive Families (PF) and they were 40/70 (57.14%), only 5% (2/40) of the PF had 100% of their members infected with the parasite. The logistic regression models applied showed that the risk categories were mainly affiliation (son/daughter) and housing (satisfactory) among others.

CONCLUSION: The presence of E. vermicularis was proved in one third of the studied population. The frequency of families with all their members infected with the parasite was very low. Most of the studied personal, sociocultural, and environmental variables did not turn out to be significantly associated with the presence of the parasite. An association with the category of "son/daughter" and housing classified as "satisfactory" was determined. The latter may be due to the fact that the people living in that category of housing have hygienic practices at home that favour the distribution of the eggs in the environment. The presence of the analysed symptoms was associated with the presence of the parasite, thus strengthening the need of periodical control of the population showing at least one of these symptoms.

Prevalence and risk factors for enterobiasis among preschool children in a metropolitan city in Korea

The infection rate of Enterobius vermicularis was investigated in 1,191 preschool children in 25 daycare centers in Seoul, Korea by cellotape anal swab from July to August 1999. Both the directors of the daycare centers and the children's parents were asked to complete questionnaires that inquired about the potential risk factors involved. The overall egg positive rate for E. vermicularis was 9.5%, and the prevalence in the daycare centers ranged from 0 to 31.1%. Children aged 6-7 years showed a significantly higher egg positive rate than younger children, but the infection rate was similar for boys and girls. The socioeconomic status of the family and personal hygiene were not associated with enterobiasis, but anthelmintic medication significantly reduced the infection rate. The daycare centers in residential areas showed significantly lower egg positive rates than those situated near traditional markets. The environment of daycare centers is an important factor in enterobiasis, and the mass screening and treatment of children at high risk is recommended.

Egg positive rate of Enterobius vermicularis of primary school children in Geoje island

The status of pinworm (Enterobius vermicularis) egg positive rate of primary school children in Geoje island was investigated by using adhesive cellotape anal swap method, in September, 2002. Total egg positive rates of E. vermicularis were 9.8% (74/754) and those of male and female were 10.8% and 8.7%, respectively. Among three schools examined, Myeongsa primary school showed the highest egg positive rate (12.6%) followed by Yeoncho [9.8% (26/266)] and Geoje [9.1% (35/385)]. As for the age groups, the 2nd grade had the highest egg positive rate (15.3%), whereas the 5th grade showed the lowest egg positive rate (2.6%). The above result led us to confirm that the egg positive rates of E. vermicularis in primary school children in Geoje island were not significantly different from the those in the whole country including urban and rural areas, showing more than 10%.

Infection status of Clonorchis sinensis in residents of Hamyang-gun, Gyeongsangnam-do, Korea

Oriental liver fluke (Clonorchis sinensis) infection was surveyed among residents of Hamyang-gun, Gyeongsangnam-do, Korea during the period of January 2001 to March 2002. Total 1,041 stool samples were collected from residents who visited Public Health Center and its branches in Hamyang-gun and examined using formalin-ether sedimentation method. The overall egg positive rate was 16%, male showing higher positive rate (21%) than female (10%). The age group of 30 to 50 years had the highest egg positive rate of C. sinensis from 20% to 22%. The positive examinees were treated with praziquantel and educated individually to prevent reinfection. Egg positive rate in this area was decreased when compared with results recorded in the past, however, still remained more than 10%. This study suggests that periodic examination, treatment as well as education of residents should be continued and systematized.