• Parasites, Hosts and Diseases
• /
• v.55 no.3
• /
• pp.247-254
• /
• 2017

ELISA has been used for the diagnosis of toxoplasmosis, but it is being gradually replaced by a rapid diagnostic test (RDT). We compared and analyzed ELISA and RDT results using the sera collected during 4 consecutive years from residents of Gyodong-do (Island), Incheon-city, Korea. Sera from 921, 993, 940, and 838 adult residents were collected on a yearly basis (2010-2013). ELISA was performed by using a crude extract of T. gondii RH strain antigen and IgG/IgM RDT mounted with recombinant fragment of major surface antigen (SAG1), GST-linker-SAG1A, were applied to the sera. Comparison between groups was analyzed by the Student's t-test. The positive seroprevalence surged from 14.7% (135/921, 2010), 23.1% (231/993, 2011), 23.6% (222/940, 2012), and 32.1% (269/838, 2013) by ELISA. In contrast, RDT showed a more moderate increasing trend from 21.7% (200/921, 2010), 25.5% (253/993, 2011), 28.9% (272/940, 2012) and 33.1% (277/838, 2013). Discrepancies between ELISA and RDT were noted near the cut-off value. At the OD 0.15-0.24 range, RDT could detect 16.1% (169/1051) more positives, which suggests an early or acute toxoplasmosis, but at the OD 0.25-0.34 range, ELISA could detect 35.9% (92/256) more positives of possible chronic infections. Over the OD > 0.35 ELISA and RDT agreed in the majority of the cases. This surge in seroprevalence may be caused by the organic agriculture in addition to eating behavior or increase in pets among Koreans. These facts may be applied on a full-scale national survey using RDT to supplement ELISA to define the characteristics of the infection.

• Korean Journal of Veterinary Service
• /
• v.38 no.4
• /
• pp.233-239
• /
• 2015

Both Q-fever and Toxoplasmosis are zoonosis. Q-fever occurs due to intracellular bacteria, while Toxoplasmosis is created by protozoan. Both of them have a wide range of host including livestock and wild animals and occur sporadically all over in the world. In this study, seroprevalence of Q-fever and Toxoplasmosis was investigated on cows bred in the area of Seoul where there was a fairly high possibility to occur, while vaccine was not used in Korea. As for experiment materials, cattle blood collected from 190 cows from February to September in 2014 was used ELISA. According to the result, there was a positive reaction on Q-fever from 18 cows out of total 190 cows (9.5%) and on Toxoplasmosis from 32 cows (16.8%). Seroprevalence of both diseases per age was turned out to be negative for those aged less than 2. In addition, it was shown to be positive on 4 cows out of 87 (4.6%) cows aged from 3 to 5, on 7 cows out of 30 cows (23.3%) aged from 6 to 7. Finally, it was shown to be positive on 7 cows out of 17 cows (41.2%) aged 8 or above. Toxoplasmosis was turned out to be positive on 1 cow out of 56 cows (1.8%) aged less than 2, on 6 cows out of 87 cows (6.9%) aged from 3 to 5, on 17 cows out of 30 cows (56.7%) aged from 6 to 7. In addition, it was turned out to be 8 cows out of 17 cows (47.1%) aged 8 or above. Seroprevalence of both diseases was turned out to be higher as age increased. Therefore, it seems that a wide range of investigation on the entire disease spreaders as well as livestock is required since infection of Q-fever and Toxoplasmosis, types of zoonosis, has continuously occurred, and the number of insects, wild animals, and stray animals serving as a role of spreading diseases by changes in seasons and environments has been gradually increasing in Korea.

• Parasites, Hosts and Diseases
• /
• v.36 no.3
• /
• pp.191-198
• /
• 1998

The responses to antifolales of ToxopLasmc Bondii were investigated by measuring the dihydrorolate redLlctase (DHFR) activity. quantity of DHFR mRNA, and single-strand conformational polymorphism (SSCP) pattern. Pyrimethamine (PYM) and methotrexate (MTX) were tested ds anlifolates. When T. gondii was treated wish PYM, the viability was decreased by the increasing concentration of PYM. DHFR activity tended to increase as the passage proceeded. and the quantity of mRNA expressed was also increased according to passages. The viability of 7. gonnii was decreased by the increasing concentration of MTX, but it was maintained over 40% up to $100{\;}{\mu\textrm{m}}$ MTX. DHFR activity was 77.4% in the 1st passage ($1{\;}{\mu\textrm{m}}$). 82.2% in the 4th passage ($10{\;}{\mu\textrm{m}}$), and 141.3% in the 7th passage ($100{\;}{\mu\textrm{m}}$) But no changes were detected in SSCP pattern of T gondii rxposvd to FYM and MTX. both. These results suggested that the response of T gondii to FYN was rofulalcd by transrriptional level and that, in MTX. the viability of T. gonnii was derived from increasing DHFK activity.