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Original Articles
Changes in the pattern and disease burden of acute respiratory viral infections before and during the COVID-19 pandemic
Chungmin Park, Donghan Lee, Bryan Inho Kim, Sujin Park, Gyehee Lee, Sangwoo Tak
Osong Public Health Res Perspect. 2022;13(3):203-211.   Published online June 30, 2022
DOI: https://doi.org/10.24171/j.phrp.2022.0144
  • 1,701 View
  • 113 Download
AbstractAbstract PDF
Objectives
We conducted a comparative analysis of the differences in the incidence of 8 acute respiratory viruses and the changes in their patterns before and during the coronavirus disease 2019 (COVID-19) pandemic. Methods: Three sentinel surveillance systems of the Korea Disease Control and Prevention Agency and data from the Health Insurance Review and Assessment Service were analyzed. The average numbers of reported cases and the related hospital admissions and outpatient data were compared between April 2018–2019 and 2020–2021. Changes in the disease burden and medical expenditures between these 2 time periods were evaluated. Results: During the COVID-19 pandemic, the number of reported cases of all acute respiratory viral infections, except for human bocavirus, decreased significantly. Data from the Health Insurance Review and Assessment Service also showed decreases in the actual amount of medical service usage and a marked reduction in medical expenditures. Conclusion: Non-pharmacological interventions in response to COVID-19 showed preventive effects on the transmission of other respiratory viruses, as well as COVID-19. Although COVID-19 had a tremendous impact on society as a whole, with high social costs, there were also positive effects, such as a reduction in the incidence of acute respiratory viral infections.
Seroprevalence of immunoglobulin G antibodies against SARS-CoV-2 in children and adolescents in Delhi, India, from January to October 2021: a repeated cross-sectional analysis
Pragya Sharma, Saurav Basu, Suruchi Mishra, Mongjam Meghachandra Singh
Osong Public Health Res Perspect. 2022;13(3):184-190.   Published online June 10, 2022
DOI: https://doi.org/10.24171/j.phrp.2022.0014
  • 1,894 View
  • 54 Download
Graphical AbstractGraphical Abstract AbstractAbstract PDF
Objectives
The aim of this study was to assess changes in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G (IgG) seroprevalence among children and adolescents in Delhi, India from January 2021 to October 2021. Methods: This was a repeated cross-sectional analysis of participants aged 5 to 17 years from 2 SARS-CoV-2 seroprevalence surveys conducted in Delhi, India during January 2021 and September to October 2021. Anti-SARS-CoV-2 IgG antibodies were detected by using the VITROS assay (90% sensitivity, 100% specificity). Results: The seroprevalence among 5- to 17-year-old school-age children and adolescents increased from 52.8% (95% confidence interval [CI], 51.3%−54.3%) in January 2021 to 81.8% (95% CI, 80.9%−82.6%) in September to October 2021. The assay-adjusted seroprevalence was 90.8% (95% CI, 89.8%−91.7%). Seropositivity positively correlated with participants’ age (p<0.001), but not sex (p=0.388). A signal to cut-off ratio ≥4.00, correlating with the presence of neutralization antibodies, was observed in 4,814 (57.9%) participants. Conclusion: The high percentage of seroconversion among children and adolescents indicates the presence of natural infection-induced immunity from past exposure to the SARS-CoV-2 virus. However, the lack of hybrid immunity and the concomitant likelihood of lower levels of neutralization antibodies than in adults due to the absence of vaccination warrants careful monitoring and surveillance of infection risk and disease severity from newer and emergent variants.
Review Article
Worldwide prevalence of fungal coinfections among COVID-19 patients: a comprehensive systematic review and meta-analysis
Saber Soltani, Milad Zandi, Samireh Faramarzi, Ramin Shahbahrami, Mohebat Vali, Sara Akhavan Rezayat, Reza Pakzad, Pooneh Malekifar, Iraj Pakzad, Neda Jahandoost, Jalal Moludi
Osong Public Health Res Perspect. 2022;13(1):15-23.   Published online February 8, 2022
DOI: https://doi.org/10.24171/j.phrp.2021.0293
  • 5,158 View
  • 82 Download
AbstractAbstract PDFSupplementary Material
Microbial coinfections can increase the morbidity and mortality rates of viral respiratory diseases. Therefore, this study aimed to determine the pooled prevalence of fungal coinfections in coronavirus disease 2019 (COVID-19) patients. Web of Science, Medline, Scopus, and Embase were searched without language restrictions to identify the related research on COVID-19 patients with fungal coinfections from December 1, 2019, to December 30, 2020. A random-effects model was used for analysis. The sample size included 2,246 patients from 8 studies. The pooled prevalence of fungal coinfections was 12.60%. The frequency of fungal subtype coinfections was 3.71% for Aspergillus, 2.39% for Candida, and 0.39% for other. The World Health Organization’s Regional Office for Europe and Regional Office for Southeast Asia had the highest (23.28%) and lowest (4.53%) estimated prevalence of fungal coinfection, respectively. Our findings showed a high prevalence of fungal coinfections in COVID-19 cases, which is a likely contributor to mortality in COVID-19 patients. Early identification of fungal pathogens in the laboratory for COVID-19 patients can lead to timely treatment and prevention of further damage by this hidden infection.
Original Article
Prevalence of plasmid-mediated AmpC β-lactamases among uropathogenic Escherichia coli isolates in southwestern Iran
Nabi Jomehzadeh, Khadijeh Ahmadi, Zahra Rahmani
Osong Public Health Res Perspect. 2021;12(6):390-395.   Published online December 1, 2021
DOI: https://doi.org/10.24171/j.phrp.2021.0272
  • 2,301 View
  • 57 Download
AbstractAbstract PDF
Objectives
This study was undertaken to evaluate AmpC β-lactamase-producing Escherichia coli urine isolates and to characterize the frequency of plasmid-mediated AmpC (pAmpC)-encoding genes.
Methods
Antimicrobial susceptibility tests were performed using the disk diffusion technique. AmpC β-lactamase production was assessed with a phenotypic inhibitor-based method. The presence of 6 pAmpC-encoding cluster genes was detected by multiplex polymerase chain reaction (PCR).
Results
The proportion of antibiotic resistance of E. coli isolates ranged from 7.4% to 90.5%, and more than half (51.6%) of the total isolates were multidrug-resistant (MDR). Among the 95 E. coli isolates, 60 (63.2%) were found to be cefoxitin-resistant, but only 14 (14.7%) isolates were confirmed as AmpC β-lactamase-producers. In the PCR assay, pAmpC-encoding genes were found in 15 (15.8%) isolates, and blaDHA was the most prevalent type. However, blaFOX, blaMOX, and blaACC genes were not detected in the isolates.
Conclusion
Our findings contributed valuable information concerning antibiotic resistance, confirmatory phenotypic testing for AmpC production, and pAmpC β-lactamase gene content in E. coli isolates in southwestern Iran. The level of MDR recorded in AmpC-producing strains of this study was worrying; therefore, implementing strong infection control approaches to reduce the MDR burden is recommended.
Brief Report
The laboratory test procedure to confirm rotavirus vaccine infection in severe complex immunodeficiency patients
Su-Jin Chae, Seung-Rye Cho, Wooyoung Choi, Myung-Guk Han, Deog-Yong Lee
Osong Public Health Res Perspect. 2021;12(4):269-273.   Published online August 13, 2021
DOI: https://doi.org/10.24171/j.phrp.2021.0079
  • 2,272 View
  • 63 Download
AbstractAbstract PDF
The rotavirus vaccine is a live vaccine, and there is a possibility of infection by the virus strain used in the vaccine. We investigated the process of determining whether an infection was caused by the vaccine strain in a severe complex immunodeficiency (SCID) patient with rotavirus infection. The patient was vaccinated with RotaTeq prior to being diagnosed with SCID. The testing process was conducted in the following order: confirming rotavirus infection, determining its genotype, and confirming the vaccine strain. Rotavirus infection was confirmed through enzyme immunoassay and VP6 gene detection. G1 and P[8] were identified by multiplex polymerase chain reaction for the genotype, and G3 was further identified using a single primer. By detecting the fingerprint gene (WC3) of RotaTeq, it was confirmed that the detected virus was the vaccine strain. Genotypes G1 and P[8] were identified, and the infection was suspected of having been caused by rotavirus G1P[8]. G1P[8] is the most commonly detected genotype worldwide and is not included in the recombinant strains used in vaccines. Therefore, the infection was confirmed to have been caused by the vaccine strain by analyzing the genetic relationship between VP4 and VP7. Rotavirus infection by the vaccine strain can be identified through genotyping and fingerprint gene detection. However, genetic linkage analysis will also help to identify vaccine strains.
Short Communications
Detection of Novel Coronavirus on the Surface of Environmental Materials Contaminated by COVID-19 Patients in the Republic of Korea
Sang-Eun Lee, Deog-Yong Lee, Wook-Gyo Lee, ByeongHak Kang, Yoon Suk Jang, Boyeong Ryu, SeungJae Lee, Hyunjung Bahk, Eungyu Lee
Osong Public Health Res Perspect. 2020;11(3):128-132.   Published online May 8, 2020
DOI: https://doi.org/10.24171/j.phrp.2020.11.3.03
  • 6,221 View
  • 264 Download
  • 19 Citations
AbstractAbstract PDF

This study aimed to determine the presence of SARS-CoV-2 on surfaces frequently touched by COVID-19 patients, and assess the scope of contamination and transmissibility in facilities where the outbreaks occurred. In the course of this epidemiological investigation, a total of 80 environmental specimens were collected from 6 hospitals (68 specimens) and 2 “mass facilities” (6 specimens from a rehabilitation center and 6 specimens from an apartment building complex). Specific reverse transcriptase-polymerase chain reaction targeting of RNA-dependent RNA polymerase, and envelope genes, were used to identify the presence of this novel coronavirus. The 68 specimens from 6 hospitals (A, B, C, D, E, and G), where prior disinfection/cleaning had been performed before environmental sampling, tested negative for SARS-CoV-2. However, 2 out of 12 specimens (16.7%) from 2 “mass facilities” (F and H), where prior disinfection/cleaning had not taken place, were positive for SARS-CoV-2 RNA polymerase, and envelope genes. These results suggest that prompt disinfection and cleaning of potentially contaminated surfaces is an effective infection control measure. By inactivating SARS-CoV-2 with disinfection/cleaning the infectivity and transmission of the virus is blocked. This investigation of environmental sampling may help in the understanding of risk assessment of the COVID-19 outbreak in “mass facilities” and provide guidance in using effective disinfectants on contaminated surfaces.

Contact Transmission of COVID-19 in South Korea: Novel Investigation Techniques for Tracing Contacts
Osong Public Health Res Perspect. 2020;11(1):60-63.   Published online February 28, 2020
DOI: https://doi.org/10.24171/j.phrp.2020.11.1.09
  • 37,415 View
  • 1,016 Download
  • 103 Citations
AbstractAbstract PDF

In the epidemiological investigation of an infectious disease, investigating, classifying, tracking, and managing contacts by identifying the patient’s route are important for preventing further transmission of the disease. However, omissions and errors in previous activities can occur when the investigation is performed through only a proxy interview with the patient. To overcome these limitations, methods that can objectively verify the patient’s claims (medical facility records, Global Positioning System, card transactions, and closed-circuit television) were used for the recent ongoing coronavirus disease 2019 contact investigations in South Korea.

Original Articles
Estimation of the Size of Dengue and Zika Infection Among Korean Travelers to Southeast Asia and Latin America, 2016–2017
Chaeshin Chu, Een Suk Shin
Osong Public Health Res Perspect. 2019;10(6):394-398.   Published online December 31, 2019
DOI: https://doi.org/10.24171/j.phrp.2019.10.6.10
  • 2,545 View
  • 53 Download
AbstractAbstract PDF
Objectives

To estimate the number and risk of imported infections resulting from people visiting Asian and Latin American countries.

Methods

The dataset of visitors to 5 Asian countries with dengue were analyzed for 2016 and 2017, and in the Philippines, Thailand and Vietnam, imported cases of zika virus infection were also reported. For zika virus, a single imported case was reported from Brazil in 2016, and 2 imported cases reported from the Maldives in 2017. To understand the transmissibility in 5 Southeast Asian countries, the estimate of the force of infection, i.e., the hazard of infection per year and the average duration of travel has been extracted. Outbound travel numbers were retrieved from the World Tourism Organization, including business travelers.

Results

The incidence of imported dengue in 2016 was estimated at 7.46, 15.00, 2.14, 4.73 and 2.40 per 100,000 travelers visiting Philippines, Indonesia, Thailand, Malaysia and Vietnam, respectively. Similarly, 2.55, 1.65, 1.53, 1.86 and 1.70 per 100,000 travelers in 2017, respectively. It was estimated that there were 60.1 infections (range: from 16.8 to 150.7 infections) with zika virus in Brazil, 2016, and 345.6 infections (range: from 85.4 to 425.5 infections) with zika virus in the Maldives, 2017.

Conclusion

This study emphasizes that dengue and zika virus infections are mild in their nature, and a substantial number of infections may go undetected. An appropriate risk assessment of zika virus infection must use the estimated total size of infections.

Relationships between Virulence Factors and Antimicrobial Resistance among Escherichia coli Isolated from Urinary Tract Infections and Commensal Isolates in Tehran, Iran
Mohammad Reza Asadi Karam, Mehri Habibi, Saeid Bouzari
Osong Public Health Res Perspect. 2018;9(5):217-224.   Published online October 31, 2018
DOI: https://doi.org/10.24171/j.phrp.2018.9.5.02
  • 3,897 View
  • 103 Download
  • 16 Citations
AbstractAbstract PDF
Objectives

Uropathogenic Escherichia coli (UPEC) are the major cause of urinary tract infections (UTIs). Here, we determined whether sensitivity to antibiotics was related to the prevalence of iron scavenging genes, or to biofilm and hemolysis formation.

Methods

A total of 110 UPEC and 30 E coli isolates were collected from the urine of UTI patients and feces of healthy individuals without UTI, respectively. The presence of iron receptor genes and phenotypic properties were evaluated by polymerase chain reaction and phenotypic methods, respectively. Susceptibility to routine antibiotics was evaluated using the disc diffusion method.

Results

The prevalence of iron scavenging genes ranged from 21.8% (ireA) to 84.5% (chuA) in the UPEC. Resistance to ceftazidime and cefotaxime was significantly correlated with the presence of fyuA and iutA iron genes. Biofilm production was significantly associated with the prevalence of fyuA and hma iron genes. A higher degree of antibiotic resistance was exhibited by isolates that produced biofilms than by their non-biofilm producing counterparts.

Conclusion

Our study clearly indicates that biofilm production is associated with antibiotic resistance, and that iron receptors and hemolysin production also contribute to reduced antibiotic sensitivity. These results further our understanding of the role that these virulence factors play during UPEC pathogenesis, which in turn may be valuable for the development of novel treatment strategies against UTIs.

Epidemiological Study on Candida Species in Patients with Cancer in the Intensive Care Unit
Young-ju Choi, Byeongyeo Lee, Sun-A Park
Osong Public Health Res Perspect. 2017;8(6):384-388.   Published online December 31, 2017
DOI: https://doi.org/10.24171/j.phrp.2017.8.6.05
  • 2,406 View
  • 22 Download
  • 1 Citations
AbstractAbstract PDF
Objectives

Although cancer survival rates have increased, serious infection complications can arise in cancer patients. Candida can occur in various tissues and has significant effects on the prognosis of patients with cancer. Thus, we conducted an epidemiological study on Candida infections in patients with cancer admitted to the intensive care unit.

Methods

A retrospective study was conducted in adult patients with cancer admitted to the intensive care unit between January 1, 2013, and December 31, 2015. Candida infection status and predictive factors for mortality were examined in 634 patients.

Results

The predictive factors for mortality included the use of steroids, use of a central venous catheter or mechanical ventilator, and identification of Candida in the blood. Patients who stayed in the surgical and intensive care unit for more than 7 days had a lower risk of death than that in those with shorter days.

Conclusion

The present study shows that invasive procedures, bloodstream infections, and the use of steroids increase the risk of mortality in Candida-infected patients with cancer. To improve the quality of life and reduce mortality, further studies are needed on the factors affecting the risk of mortality associated with Candida infection.

Review Article
Foodborne Infectious Diseases Mediated by Inappropriate Infection Control in Food Service Businesses and Relevant Countermeasures in Korea
Jong Myong Park, Young-Hyun You, Hyun-Min Cho, Ji Won Hong, Sa-Youl Ghim
Osong Public Health Res Perspect. 2017;8(3):159-168.   Published online June 30, 2017
DOI: https://doi.org/10.24171/j.phrp.2017.8.3.02
  • 3,030 View
  • 30 Download
  • 5 Citations
AbstractAbstract PDF
Objectives

The objective of this review is to propose an appropriate course of action for improving the guidelines followed by food handlers for control of infection. For this purpose, previous epidemiological reports related to acute gastroenteritis in food service businesses mediated by food handlers were intensively analyzed.

Methods

Relevant studies were identified in international databases. We selected eligible papers reporting foodborne infectious disease outbreaks. Among primary literature collection, the abstract of each article was investigated to find cases that absolutely identified a causative factor to be food handlers’ inappropriate infection control and the taxon of causative microbial agents by epidemiological methodologies. Information about the sites (type of food business) where the outbreaks occurred was investigated.

Results

A wide variety of causative microbial agents has been investigated, using several epidemiological methods. These agents have shown diverse propagation pathways based on their own molecular pathogenesis, physiology, taxonomy, and etiology.

Conclusion

Depending on etiology, transmission, propagation, and microbiological traits, we can predict the transmission characteristics of pathogens in food preparation areas. The infected food workers have a somewhat different ecological place in infection epidemiology as compared to the general population. However, the current Korean Food Safety Act cannot propose detailed guidelines. Therefore, different methodologies have to be made available to prevent further infections.

Original Articles
Estimating Tuberculin Skin Test Reactions among Children and Teenagers Who Received the Bacillus Calmette-Guerin Vaccination at Birth: A Meta-analysis
Mohammad Sadegh Rezai, Siavosh Abedi, Mahdi Afshari, Mahmood Moosazadeh
Osong Public Health Res Perspect. 2017;8(1):3-10.   Published online February 28, 2017
DOI: https://doi.org/10.24171/j.phrp.2017.8.1.02
  • 2,567 View
  • 24 Download
  • 2 Citations
AbstractAbstract PDF
Objectives

Tuberculin skin reaction size is one indicator of bacillus Calmette-Guérin (BCG) vaccine efficacy and a way to diagnose latent infection. Several primary studies have examined this issue. Combining the results of these studies using a meta-analysis will provide reliable evidence regarding this indicator for policymakers. This study aimed to estimate the total frequency of different tuberculin skin test reactions among Iranian children and teenagers who received the BCG vaccination at birth.

Methods

National and international databanks were searched using relevant keywords. After the search strategy was restricted and duplicates were excluded, the titles and abstracts of the remaining papers were screened. All included studies included healthy children who received the BCG vaccine without confirmed tuberculosis exposure. Heterogeneity of the results was assessed using the Cochrane test and I2 index showed the random effects model as the best model for estimating the pooled results.

Results

We combined the results of 14 primary studies including purified protein derivative reaction test measures of 26,281 Iranian children. The frequencies (95% confidence intervals) of the reactions were 8.5% (6.2–10.8) for patients with a reaction size ≥ 10 mm, 29.9% (22.3–37.4) for a reaction size of 5–9 mm, and 60% (48.9–71.1) for a reaction size < 5 mm.

Conclusion

Our study showed that large numbers of Iranian children and teens have no positive BCG vaccine reaction and a considerable number of children have been exposed to Mycobacterium tuberculosis.

Epidemiological Characterization of Skin Fungal Infections Between the Years 2006 and 2010 in Korea
Sang-Ha Kim, Seung-Hak Cho, Seung-Ki Youn, Je-Seop Park, Jong Tae Choi, Young-Seok Bak, Young-Bin Yu, Young Kwon Kim
Osong Public Health Res Perspect. 2015;6(6):341-345.   Published online December 31, 2015
DOI: https://doi.org/10.1016/j.phrp.2015.10.012
  • 2,473 View
  • 22 Download
  • 9 Citations
AbstractAbstract PDF
Objectives
The purpose of this study was to build and provide a basic database of skin fungal infections for the effective management of skin fungal infections in the future.
Methods
We collected health insurance data between the years 2006 and 2010 from the Health Insurance Corporation (Seoul, Korea) and analyzed the data to determine the prevalence and treatment management of skin fungal infections.
Results
Skin fungal infections were divided into two groups: namely dermatophytosis and other superficial mycoses. Dermatophytosis showed a higher prevalence (16,035,399 cases) than the other superficial mycoses (794,847 cases) within the study period. The prevalence rate decreased consecutively by 0.01% to 0.19% every year. The prevalence according to region showed that Jeolla-do had a high prevalence distribution. The prevalences in men and women were similar (7.01% vs. 6.26%). It is interesting to note that adults from the 50–79-year age group showed a higher prevalence than children and young adults. The average convalescence time (days) of dermatophytosis was longer than that of other superficial mycoses. The total medical expenses were also much higher in dermatophytosis than in the other superficial mycoses.
Conclusion
This study provides useful data for study trends of skin fungal infections.
Phenotypic Assays to Determine Virulence Factors of Uropathogenic Escherichia coli (UPEC) Isolates and their Correlation with Antibiotic Resistance Pattern
Mohsen Tabasi, Mohammad Reza Asadi Karam, Mehri Habibi, Mir Saeed Yekaninejad, Saeid Bouzari
Osong Public Health Res Perspect. 2015;6(4):261-268.   Published online August 31, 2015
DOI: https://doi.org/10.1016/j.phrp.2015.08.002
  • 2,086 View
  • 18 Download
  • 39 Citations
AbstractAbstract PDF
Objectives
Urinary tract infection caused by uropathogenic Escherichia coli (UPEC) strains is one of the most important infections in the world. UPEC encode widespread virulence factors closely related with pathogenesis of the bacteria. The purpose of this study was to evaluate the presence of different phenotypic virulence markers in UPEC isolates and determine their correlation with antibiotic resistance pattern.
Methods
UPEC isolates from patients with different clinical symptoms of UTI were collected and screened for biofilm and hemolysin production, mannose resistant, and mannose sensitive hemagglutination (MRHA and MSHA, respectively). In addition, antimicrobial resistance pattern and ESBL-producing isolates were recorded.
Results
Of the 156 UPEC isolates, biofilm and hemolysin formation was seen in 133 (85.3%) and 53 (34%) isolates, respectively. Moreover, 98 (62.8%) and 58 (37.2%) isolates showed the presence of Types 1 fimbriae (MSHA) and P fimbriae (MRHA), respectively. Our results also showed a relationship between biofilm formation in UPEC isolated from acute cystitis patients and recurrent UTI cases. Occurrence of UTI was dramatically correlated with the patients' profiles. We observed that the difference in antimicrobial susceptibilities of the biofilm and nonbiofilm former isolates was statistically significant. The UPEC isolates showed the highest resistance to ampicillin, tetracycline, amoxicillin, and cotrimoxazole. Moreover, 26.9% of isolates were ESBL producers.
Conclusion
This study indicated that there is a relationship between the phenotypic virulence traits of the UPEC isolates, patients' profiles, and antibiotic resistance. Detection of the phenotypic virulence factors could help to improve understanding of pathogenesis of UPEC isolates and better medical intervention.
Modification of AxSYM Human Immunodeficiency Virus Assay to Identify Recent Human Immunodeficiency Virus Infections in Korean Human Immunodeficiency Virus-Positive Individuals
Jin-Sook Wang, Mee-Kyung Kee, Byeong-Sun Choi, Sung Soon Kim
Osong Public Health Res Perspect. 2015;6(3):184-191.   Published online June 30, 2015
DOI: https://doi.org/10.1016/j.phrp.2015.06.002
  • 1,584 View
  • 18 Download
  • 1 Citations
AbstractAbstract PDF
Objectives
To estimate human immunodeficiency virus (HIV) incidence using HIV avidity assays in Korea, we established a serological testing method to differentiate recent HIV infections from long-standing ones.
Methods
We adopted two incidence assays, the BED HIV-1 incidence test (Calypte Biomedical) and an HIV avidity assay (using Abbott AxSYM HIV Antigen/Antibody Combo), and performed them on Korean HIV samples obtained from 81 HIV seroconverters (n = 193), 135 HIV-positive samples, and three HIV commercial incidence panels (PRB965, PRB933, and PRB601 from SeaCare). To determine the most optimal concentration of the chaotropic agent (Guanidine) and the cutoff value for the avidity assay, we evaluated the sensitivity and specificity of the assay at different concentration levels.
Results
We determined that the concentration of Guanidine to be used in the avidity assay was 1.5M. The cutoff value of the avidity index (AI) was 0.8, and the sensitivity and specificity were 90.2% and 83.8%, respectively, under this condition. The gray zone for the avidity assay was 0.75–0.85 AI. The mean of coefficient of variation was low, at 5.43%.
Conclusion
An optimized avidity assay for the diagnosis of recent HIV infections using Korean samples was established. This assay will be applied to investigate the level of recent infection and will provide basic data to the HIV prevention policy in Korea.

PHRP : Osong Public Health and Research Perspectives