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Results for “seroconversion”

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PubMed1998

Hepatitis B vaccination program at a New York City hospital: seroprevalence, seroconversion, and declination.

BACKGROUND: Despite implementation of hepatitis B vaccination programs, 2 problems have prevented full vaccine-induced protection of health care workers (HCWs). About 10% to 12% of vaccinated HCWs do not develop antibody, and many HCWs continue to decline vaccination. To determine the effectiveness of our hepatitis B vaccine program, we studied rates of postvaccination seroconversion and vaccine declination. METHODS: Employee health service records were used to determine demographic features, hepatitis B surface antibody serostatus at baseline, serologic response to vaccine, and declination or acceptance of vaccine. RESULTS: About 26% of HCWs were seropositive at baseline, including those vaccinated before employment. Higher seroprevalence rates were seen among those born outside the United States, nurses, and laboratory workers. Seroconversion occurred in only 79% of HCWs who completed a 3-vaccine series. Increasing age was the only significant risk for failure to convert. Declination rates overall were about 45% and were lowest in HCWs who have jobs that included potential exposure to blood. CONCLUSION: Hepatitis B seroprevalence among HCWs at our hospital is higher than in many other urban hospitals in the United States; over postvaccination seroconversion rate is substantially lower; and our declination rate of 45% resembles other published series. Declination of vaccine and failure to respond to vaccine continue to thwart achievement of full control of this preventable occupational infection.

Adult↗

PubMed2000

Seroconversion and duration of immunity after vaccination against group C meningococcal infection in young children.

An increase in the incidence of group C meningococcal disease was observed in the Murcia Region (Spain) during 1996-1997. In September 1997, a massive vaccination campaign was implemented among the population aged 18 months to 19 years. The aim of this study was to assess the seroconversion rate of children aged 18-59 months and the persistence of immune response 1 year after vaccination. A total of 296 children were included. Blood samples were obtained before vaccination and 1 month and 1 year after vaccination. Three point seven percent of the children had bactericidal antibody titres of >/=1:8 before vaccination. One month after vaccination seroconversion was 63.7%, with a growing trend related to age at vaccination (p<0.0001). The increase in antibody titres was shown to be quantitatively greater above the age of 36 months (p<0.0001). One year after vaccination only 4.3% of the children who initially seroconverted still had bactericidal activity. Seroconversion in children under 5 increases with age but antibodies decline rapidly in the year following vaccination.

Antigens, Bacterial↗

PubMed2002

A high rate of seroconversion for Neospora caninum in a dairy herd without an obvious increased incidence of abortions.

The purpose of this paper is to investigate the high rate of seroconversion for Neospora caninum in a dairy herd. Forty-five of 95 (47%) of the seronegative animals seroconverted within a period of 6 months. Seropositive animals were not equally distributed among age-groups. A high seroprevalence age-group of 8-30 months was housed together during a period of 4 months, indicating a point source infection within this period. A lack of association between the serological status of daughters and mothers also indicated horizontal transmission of the infection. Low avidity indices in the seroconverted animals confirmed a recent infection in this herd. However, there was no increased abortion rate in connection with the seroconversion, which indicates that mass seroconversions in dairy herds may remain unnoticed. There was circumstantial evidence that the farm dog played a role in the transmission of the infection to the cattle. However, also evidence was found for an unexplained ongoing horizontal transmission after the initial point source exposure.

Abortion, Veterinary↗

PubMed2004

[Toxoplasmosis seroconversion in pregnant women. The differing attitudes in France].

INTRODUCTION: Since 1992 France has been running a toxoplasmosis prevention program based on the serological detection of infections during pregnancy. In the absence of a consensus, the seroconversions discovered are managed in different ways, varying from one centre to another. OBJECTIVE: To describe the habits of the specialised centres in France and propose means to reduce the heterogeneity. METHODS: A survey using a questionnaire mailed to the centres of parasitology in France specialised in the management of toxoplasmosis seroconversion during pregnancy. RESULTS: All the 30 centres surveyed replied. Five of them do not provide recommendations for treatment and were excluded from analysis. The attitudes of the 25 other centres varied greatly with regard to the indications for therapeutic abortion and amniocentesis, treatment protocols with pyrimethamine and sulfamides, as well as in the frequency of sonographical monitoring. CONCLUSION: In the absence of National guidelines, the management of seroconversions discovered during the prenatal prevention of congenital toxoplasmosis program is left to the discretion of the specialised centre. This results in variations from one town to the next. This heterogeneity underlines the lack of knowledge on the most efficient and acceptable means of preventing and treating congenital toxoplasmosis. In order to improve this situation, the French parasitologists have launched a program of consensual meetings aimed at harmonising the treatment protocols and identifying the points that require further studies.

Adult↗

PubMed1995

Time course of detection of viral and serologic markers preceding human immunodeficiency virus type 1 seroconversion: implications for screening of blood and tissue donors.

BACKGROUND: Almost all human immunodeficiency virus (HIV) transmission via blood or tissues that has occurred since anti-HIV screening was implemented in 1985 is traceable to blood given after infection but before antibody seroconversion, a time that is referred to as the window period. In this study, the performance of newer assays designed to detect viral and serologic markers soon after infection is assessed, and the reduction in the window period achieved by these assays is estimated. STUDY DESIGN AND METHODS: Three cohort studies of persons at high risk for acquiring HIV infection were identified. These studies included well-controlled HIV type 1 (HIV-1) polymerase chain reaction (PCR) analyses of serial preseroconversion specimens from HIV-1-seroconverting homosexual men or intravenous drug users. Of 81 enrollees with anti-HIV-1 seroconversion documented by a viral lysate anti-HIV-1 enzyme immunosorbent assay (EIA) available in 1989, 13 (16%) had PCR-positive preseroconversion specimens. In the present study, sera from these 13 PCR-positive samples were further tested for anti-HIV by 10 contemporary EIAs and 6 supplemental assays, as well as being tested for plasma p24 antigen and HIV-1 RNA. Preseroconversion sera from 38 HIV-1 DNA PCR-negative cohort participants were also tested by selected anti-HIV EIAs and tested for p24 antigen and HIV-1 RNA. On the basis of these laboratory data and the intervals between blood drawing in all 81 men, the reduction in the preseroconversion window period achieved by these new assays was estimated with a mathematical model developed to analyze seroconversion data. RESULTS: Nine (69%) of the 13 preseroconversion PCR-positive samples had anti-HIV that was detectable by one or more contemporary anti-HIV-1 or anti-HIV type 2 EIA. Supplemental antibody assays were negative on all four EIA-nonreactive preseroconversion samples and negative or indeterminate on a high proportion of the nine EIA-reactive PCR-positive samples. Eight (61%) of the 13 samples were p24 antigen-positive, and 11 (85%) were HIV-1 RNA-positive. The estimated reductions in the window period (relative to the index viral lysate-based anti-HIV EIA) were as follows: contemporary anti-HIV-1/2 EIAs, 20.3 days (95% Cl, 8.0-32.5); p24 antigen and DNA PCR, 26.4 days (95% Cl, 12.6-38.7); and RNA PCR, 31.0 days (95% Cl, 16.7-45.3). CONCLUSION: Recent improvement in the sensitivity of anti-HIV assays has resulted in significant shortening of the preseroconversion window period. Consequently, the incremental reduction in the window period that could be achieved by implementing direct virus-detection assays has diminished significantly.

Blood Donors↗

PubMed1999

Seroindeterminate patterns and seroconversions to human T-lymphotropic virus type I positivity in blood donors from Martinique, French West Indies.

BACKGROUND: Screening for human T-lymphotropic virus type I (HTLV-I) antibodies in volunteer blood donors has been systematic in the French West Indies since 1989. Western blot-indeterminate results are commonly obtained. The significance of these indeterminate serologic patterns in HTLV-I-endemic areas is still unclear. STUDY DESIGN AND METHODS: During a 2-year period, 9759 blood donors were tested for HTLV-I antibodies. The epidemiologic features of HTLV-I-seropositive, -seroindeterminate, and -seronegative donors were compared. A lookback investigation was performed for the HTLV-I-seropositive donors, and the HTLV-I-seroindeterminate individuals were followed up. RESULTS: Thirty-nine donors (0.4%) were HTLV-I seropositive and 49 (0.5%) were seroindeterminate. The age and sex ratio characteristics of the seroindeterminate donors are divergent from those of the HTLV-I-seropositive group and are more like those of the seronegative population. However, during the study period, three cases of seroconversion after an initial seroindeterminate profile were reported. Two cases were detected through follow-up of 38 HTLV-I-seroindeterminate donors over a mean of 8 months (2-24 months). The third seroconverter belonged to the HTLV-I-seropositive group and was identified through lookback investigation. This case is atypical, with p19 reactivity for several months before HTLV-I seropositivity. CONCLUSION: These findings indicate that, although HTLV-I-seroindeterminate donors mainly are HTLV-I-noninfected, the rate of seroconversion in a repeat blood donor population from an endemic region must be taken into consideration. Moreover, the case of delayed seroconversion observed in this study suggests the difficulty of counseling seroindeterminate blood donors in endemic regions.

Adult↗

PubMed2002

Quantification of HCV RNA levels and detection of core antigen in donations before seroconversion.

BACKGROUND: Detection of HCV during the window phase of infection before seroconversion is important in blood screening. HCV RNA levels were measured before seroconversion and compared with HCV core antigen and anti-HCV detection. STUDY DESIGN AND METHODS: A total of 41 plasma samples from 17 US plasmapheresis donors and one English National Blood Service donor in the window phase before seroconversion of HCV infection were tested for the presence of anti-HCV, HCV RNA, and HCV core antigen. RESULTS: HCV RNA levels between 5.4 x 10(2) and 3.4 x 10(7) IU per mL were measured. HCV core antigen was detected in 11 of 18 donors at the same time point as RNA was detected. CONCLUSIONS: A wide range of HCV RNA levels can be detected during the seronegative window phase of HCV infection. HCV core antigen can be used to detect HCV infection during the window phase of infection.

Antigen-Antibody Reactions↗

PubMed2003

Stage of chronic kidney disease predicts seroconversion after hepatitis B immunization: earlier is better.

BACKGROUND: Hepatitis B virus (HBV) infection remains a concern in dialysis populations, and vaccination programs have been less successful than those in the general population. Reasons for poor response include malnutrition, uremia, and the generalized immunosuppressive state of patients with chronic kidney disease (CKD). This prospective cohort study evaluated factors impacting on the effectiveness of a vaccination program before dialysis therapy initiation, including level of kidney function. METHODS: All patients receiving care in the Kidney Function Clinic (St Paul's Hospital, Vancouver, Canada) were screened for previous HBV infection or vaccination. Those who were marker negative were administered a standardized hepatitis B vaccination schedule recommended for patients with CKD. The primary outcome measure, seroconversion, is defined as hepatitis B surface antibody titer greater than 10 IU 3 months after completion of the vaccination schedule. RESULTS: The study population of 165 patients included 64% men with a mean age of 60 years, mean serum creatinine level of 3.4 +/- 1.5 mg/dL (300 +/- 133 micromol/L), and median estimated glomerular filtration rate (GFR) of 20 mL/min (interquartile range, 14 to 20). Seroconversion rate was 82%. Multivariate analyses showed the independent predictive value of level of GFR. The model showed that patients with the lowest level of kidney function and who were older and had diabetes were less likely to seroconvert (P < 0.05). CONCLUSION: This is the largest study to show in a well-characterized cohort that patients with higher GFR levels are more likely to respond to hepatitis B vaccination programs with seroconversion, independent of other factors. Future studies will explore specific mechanisms to explain this phenomenon.

Aged↗

PubMedDate not supplied

Seroconversion issues among out-of-treatment injection drug users.

Many risk factors for HIV incidence among drug users have been reported in the literature. However most of these studies have been with local samples, and typically have had limited sample sizes. The National Institute on Drug Abuse (NIDA) funded a Cooperative Agreement for AIDS Community-Based Outreach/Intervention Research (CA) since 1991 that produced a national database. Associations found in the literature were tested to determine whether they were replicated on this national database. The CA national database had complete data, including blood draws six months apart, on 6,970 drug users who were seronegative at baseline. Sites that had no seroincident cases were excluded from the analysis. Twenty-nine risk factors identified in the literature were tested on the national database on a bivariate basis. There were 56 seroincident cases (those who were HIV-seronegative at baseline and HIV-seropositive at follow-up) out of 3752 person years at risk, for a seroconversion rate of 1.49 (CI 1.05, 1.94) per 100 person years at risk. Data were analyzed both as a whole dataset and with the sites stratified by high and low prevalence. In the overall analysis, risk factors associated with seroconversion were times injected any drug, ever injected any drug, days injected cocaine, times injected cocaine, and times injected speedball (these variables had a 30-day time referent). Also significant was how recently formerly-used injection equipment was used. High-prevalence sites revealed associations for times injected any drug, days injected cocaine, and times injected speedball. Low-prevalence sites revealed associations for injected any drug and days injected cocaine. These findings highlight the importance of injection drug use, especially cocaine injection, as a major risk factor in recent seroconversion.

Adult↗

PubMed2000

Social and behavioural factors associated with HIV seroconversion in homosexual men attending a central London STD clinic: a feasibility study.

An unmatched retrospective case control study was conducted to test the feasibility of investigating social and behavioural factors which may have contributed to recent HIV seroconversion in a group of homosexual men. Participants, recruited from a London sexually transmitted disease (STD) clinic, were sexually active and had had a negative HIV test with a subsequent test (positive (cases) or negative (controls)) within three to 15 months. Twenty cases and 22 controls were recruited between February and October 1995. There was no difference between cases and controls in: the number of regular or casual sexual partners, the proportion who were unaware of their regular partners' serostatus (cases 60%, controls 59%), or the proportion who had known HIV-positive regular partners (cases 20%, controls 23%). A significant difference in sexual behaviour was found only when the HIV status of partners, if known, was taken into account: cases were more likely than controls to have had unprotected receptive anal intercourse with a partner not known to be HIV-negative (OR = 5.5, CI = 1.15-29.50). Fifty per cent of the cases and 27% of the controls acquired acute STDs between the two HIV tests. All participants achieved high self-efficacy scores, but the controls believed their peers placed a greater value on safer sex. Cases cited emotional issues and the use of drugs and alcohol as contributing to their seroconversion, whereas controls cited a commitment to safer sex and the avoidance of high-risk situations as contributing to their remaining HIV-negative. The results illustrate the importance of acknowledging the concept of 'negotiated safety' in studies of sexual behaviour; seroconversion was only associated with unprotected sex with a partner not known to be HIV-negative. Despite high self-efficacy scores, indicating the skills to negotiate safer sex, high levels of unsafe anal intercourse were reported. Differences between cases and controls included the importance of safer sex, periods of emotional vulnerability, influence of peers and the appropriate use of condoms. There is a need for these results to be confirmed in a larger and more powerful study.

Adult↗

PubMed1992

Methadone maintenance treatment and HIV type 1 seroconversion among injecting drug users.

This study examined whether methadone maintenance treatment decreases drug injection enough to significantly limit HIV-1 transmission among injection drug users (IDU). When HIV-1 seroconversion status among prospectively followed methadone maintenance clients was analyzed by treatment retention, 1/56 (2%) of those who remained continuously in treatment seroconverted while 8/42 (19%) of those whose methadone treatment was interrupted seroconverted. When controlled for length of follow up, the difference in seroconversion rate was not statistically significant. Subjects in continuous treatment had a seroconversion rate of 0.7 per 100 person years (95% Confidence Interval [CI] = 0.1, 5.3) and those with interrupted treatment a rate of 4.3 per 100 person years (95% CI = 2.2, 8.6). Subjects in continuous treatment reported less needle sharing (p less than 0.0002), fewer needle sharing partners (p less than 0.002), fewer sexual partners (p less than 0.03), and were more likely to be women (p less than 0.01). These data indicate the need for larger studies to evaluate both client and drug treatment program characteristics which might concomitantly increase treatment retention and decrease HIV-1 risk.

Adult↗

PubMed2006

Binge drug use independently predicts HIV seroconversion among injection drug users: implications for public health strategies.

Several studies have highlighted risk factors that cause HIV vulnerability among injection drug users (IDUs); these studies in turn have prompted public health officials to take action to minimize these risks. We sought to evaluate the potential association between binge drug use and HIV seroconversion and, subsequently, risk factors associated with binge drug use among a cohort of IDUs. To do this, we performed analyses of (1) associations with HIV seroconversion and (2) associations with binge drug use among participants enrolled in the Vancouver Injection Drug Users Study (VIDUS), a prospective cohort of IDU. Because serial measures for each individual were available, we undertook a time-updated Cox regression analysis to detect associations with HIV incidence and variables potentially associated with binge drug use were evaluated by using generalized estimating equations (GEE). Overall, 1548 IDU were enrolled into the VIDUS cohort between May 1996 and May 2003. There were 1013 individuals who were HIV seronegative at enrollment and had at least one follow-up visit; 125 (12%) became HIV positive during the study period for a cumulative incidence rate of 14% at 64 months after enrollment. In the final multivariate model, binge drug use [Adjusted Hazards Ratio: 1.61 (CI: 1.12, 2.31)] was independently associated with HIV seroconversion. In subanalyses, when we evaluated associations with binge drug use in GEE analyses, borrowing [Odds Ratio (OR): 153 (CI: 1.33-1.76)] and lending [OR: 1.73 (CI: 1.50-1.98)] syringes, sex trade work [OR: 1.14 (CI: 1.01-1.29)], frequent cocaine [OR: 2.34 (CI: 2.11-2.60)] and heroin [OR: 1.29 (CI: 1.17-1.43)] injection were independently associated with binge drug use and methadone [OR: 0.80 (CI: 0.71-0.89)] was protective against binge drug use. Our study identified an independent association between binge drug use and HIV incidence and demonstrated several high-risk drug practices associated with bingeing. Given the unaddressed public health risks associated with bingeing, a public health response protocol must be developed to minimize the personal and public health risks associated with the binge use of drugs.

British Columbia↗

PubMed1999

Longitudinal human immunodeficiency virus type 1 load in the italian seroconversion study: correlates and temporal trends of virus load.

A prospective study of 149 human immunodeficiency virus type 1 (HIV-1) seroconverters was conducted to describe trends and correlates of HIV-1 load after seroconversion and over time. HIV-1 load was quantified from frozen sera by reverse transcriptase-polymerase chain reaction. High early virus load was associated with lower CD4 cell counts and male sex but not with age at seroconversion or injection drug use. Early virus load predicted progression to clinical AIDS and AIDS/<200 CD4 cells/microL. Virus load exhibited a decline of 52% by 18 months after seroconversion then increased 23% annually (95% confidence interval, 13%-33%). Men and those developing AIDS during follow-up had higher virus loads over the course of disease. Persons who developed AIDS had a steeper virus load slope than those who were AIDS-free (P=.01). In long-term follow-up, virus load exhibited a gradual and sustained increase over time. Virus load and annual increase are strong predictors of disease progression.

Acquired Immunodeficiency Syndrome↗

PubMed1999

Seroconversion rates in healthcare workers using a latex agglutination assay after varicella virus vaccination.

OBJECTIVES: To determine the seroconversion rate after varicella immunization of healthcare workers (HCWs) and the effect of seroconversion rate on current cost-based recommendations for universal vaccination. METHODS: A voluntary vaccination program for HCWs was performed at a tertiary-care cancer center in New York City. A commercial latex agglutination assay was used to test postvaccination antibody response. Costs for vaccination and postvaccination serological testing were compared to potential costs of postexposure employee furloughs. RESULTS: Of 263 seronegative HCWs, 96 (36.5%) began the vaccine program. Thirty-nine HCWs received only one dose of vaccine. Seven returned for follow-up antibody testing, of whom 4 were seropositive. Of the 57 HCWs who received two doses, 38 returned for follow-up serology. Thirty-one (81.6%) HCWs were seropositive for varicella-zoster virus antibodies, and seven HCWs (18.4%) remained seronegative. Total cost of vaccination for all 263 seronegative HCWs was estimated and compared to the cost of varicella-related furloughs at our institution. CONCLUSIONS: We found a considerably lower rate of vaccine-induced seroconversion at our hospital compared to that of the published literature. Despite this finding, universal varicella vaccination remained an extremely cost-effective alternative to the furloughing of exposed, seronegative HCWs. Projected hospital savings exceeded $53,000 in the first year after vaccination alone.

Adult↗

PubMed2006

A cohort study among university students: identification of risk factors for Epstein-Barr virus seroconversion and infectious mononucleosis.

BACKGROUND: A vaccine against Epstein-Barr virus (EBV) infection is in clinical trials. Up-to-date information on risk factors for EBV infection and infectious mononucleosis (IM) among young adults is required to inform a vaccination strategy. METHODS: We carried out a prospective study on a cohort of university students. All EBV-seronegative students were asked to report symptoms of IM and were followed up 3 years later to undergo repeat EBV testing and to complete a lifestyle questionnaire. EBV typing was performed for these subjects, as well as for students who were EBV seropositive at enrollment and for additional students with IM. RESULTS: A total of 510 students (25%) who took part in the study were EBV seronegative when they entered the university; of the 241 who donated a second blood sample 3 years later, 110 (46%) had seroconverted to EBV, 27 (25%) of whom developed IM [corrected] Penetrative sexual intercourse was a risk factor for EBV seroconversion (P = .004), but neither condom use nor oral sex significantly altered the rate of seroconversion. EBV type 1 was significantly overrepresented in IM, compared with silent seroconversion (P = .001). CONCLUSIONS: Our findings suggest that acquisition of EBV is enhanced by penetrative sexual intercourse, although transmission could occur through related sexual behaviors, such as "deep kissing." We also found that EBV type 1 infection is significantly more likely to result in IM. Overall, the results suggest that a large EBV type 1 load acquired during sexual intercourse can rapidly colonize the B cell population and induce the exaggerated T cell response that causes IM. Thus, IM could, perhaps, be prevented with a vaccine that reduces the viral load without necessarily inducing sterile immunity.

Adult↗

PubMed1997

Is there a general tendency for CD4 lymphocyte decline to speed up during human immunodeficiency virus infection? Evidence from the Italian Seroconversion Study.

It has been suggested that the rate of CD4 cell decline accelerates in parallel with decreasing numbers of cells; however, the statistical literature suggests the opposite. CD4 cells were counted about every 6 months in a cohort of 1264 human immunodeficiency virus-infected subjects (the Italian Seroconversion Study cohort). Kaplan-Meier analysis was used to estimate the time for CD4 cells to decline by 100 cells/mm3, conditional on reaching predefined levels. In addition, CD4 cell counts were modeled as a function of time since seroconversion in individuals with > or = 5 counts. Kaplan-Meier survival times for a 100 cell/mm3 decrease in CD4 cells increased as lower counts were reached (log rank test, P < .001). The shape of the overall fitted curve of the CD4 cell counts does not suggest an increasing rate of decline. Data from the Italian Seroconversion Study cohort do not show a general tendency for accelerating CD4 cell decline in association with lower counts.

CD4 Lymphocyte Count↗

PubMed1997

Seroconversion to human herpesvirus 6 following liver transplantation is a marker of cytomegalovirus disease.

Human herpesvirus 6 (HHV-6) infection is common after transplantation; HHV-6 is known to interact with other viruses and induce immunosuppression. Whether HHV-6 plays a role in the occurrence of cytomegalovirus (CMV) infection after transplantation was investigated. In a cohort of 247 liver transplant recipients, HHV-6 seroconversion was identified as a significant risk factor for development of symptomatic CMV infection (P < .001), including CMV organ involvement (P < .001), even in the presence of the other significant risk factors: D+/R- CMV serologic status (P < .001) or use of OKT3 after transplantation (P = .002). Subgroup analysis indicated that HHV-6 seroconversion was significantly associated with symptomatic CMV infection in the D+/R+ but not in the D+/R- CMV serologic group (P < .001 and P = .11, respectively). These results indicate that HHV-6 seroconversion is a marker for CMV disease after transplantation and suggest that additional studies using more sensitive diagnostic techniques are warranted to determine the relationship between HHV-6 and CMV infection after transplantation.

Adult↗

PubMed1997

Spontaneous seroconversion in hepatitis B e antigen-positive chronic hepatitis B: implications for interferon therapy.

This study compared rates of spontaneous hepatitis B e antigen (HBeAg)-positive to -negative seroconversion in chronic carriers of hepatitis B virus (HBV) with rates reported during interferon-alpha therapy. Four hundred fifty-four Asian-American HBeAg-positive HBV carriers, followed for 1-10 years, were tested approximately every 6 months for HBeAg. Patients with alanine aminotransferase levels > or = 50 IU/mL at entry had 1067.3 seroconversions/10(5) person-months in the 5- to 19-year age group, 1753.3 in the 20- to 34-year group, and 1257.2 in the 35- to 50-year group. Published data indicate that 30% of children and 33% of adults seroconvert during interferon-alpha treatment and follow-up. In our study population, spontaneous seroconversion occurred in 15% of children (95% confidence interval [CI], 8%-27%), 23% of adults 20-34 years (95% CI, 15%-34%), and 17% of adults 35-50 years (95% CI, 10%-28%) during the same interval. The high rate of spontaneous seroconversion should be weighed in decisions to treat HBV carriers with interferon-alpha.

Adolescent↗