[Influence of the treatment of chronic hepatitis B on HBV DNA suppression and prevention of disease progression]

Appropriate treatment for chronic hepatitis B to present disease progression and clinical complications requires an accurate knowledge of the natural history of this disorder. The natural course of chronic HBV infections now perceive as consisting of 4 phases: immune tolerance, immune clearance, inactive carrier state and reactivation. In patients who acquire the disease in early life complications of CHB continue to develop because of the prolonged insidious damage to the liver. Measurement of serum HBV DNA is the most important factor to evaluate disease activity, assess the efficacy of antiviral therapy and predict treatment outcomes. It was shown that higher HBV DNA levels are associated with increased risk of progression to cirrhosis and HCC. Long-term suppression of viral replication to very low levels with nucleoside (nucleotide) analogues has been shown to decrease or delay liver disease progression and even partially reverse preexisting fibrosis and cirrhosis.

[Infections with hepatitis B virus in hemodialysis units of Wielkopolska]

OBJECTIVE

Epidemiological analysis of HBV infections in dialysis units of Wielkopolska.

METHODS

Studies were carried out in 19 dialysis units, in which patients were treated with intermittent hemodialysis (IHD). Data were collected from 18.04.2007 to 18.06.2007.

MAIN OBSERVATIONS

There were 39 persons with HBsAg(+) among 1140 patients (3.42%). Positive results of HBcAb were shown in 114 from 349 examined patients with HBsAg(-) (32.7%). The group with HBsAg(+) consisted of 7 women (17.9%) and 32 men (82.1%). Documented duration of HBV infection was 9.7 +/- 6.0 years. Eight patients before detection of HBsAg(+) were vaccinated against hepatitis B; 21 patients (53.8%) underwent surgical interventions or invasive diagnostic procedures. Transfusions of blood or blood-related products were documented in 17 cases (43.6%). HBV infection in at least 32 patients (82.1%) was not connected with IHD treatment (p = 0.000). Four patients (10.3%) showed symptoms of acute hepatitis. Eleven patients (28.2%) with HBsAg(+) had renal transplantation. Patients with HBsAg(-) were vaccinated against hepatitis B. Vaccination was not effective (level of HBsAb < 10 IU/l) in 244 patients (22.2%).

CONCLUSIONS

HBV infection in patients with chronic kidney disease is most frequently detected before or due to initiation of IHD treatment. Over 20% IHD patients remains susceptible for HBV infection despite vaccination against hepatitis B.

Detection and characterization of hepatitis B virus of anti-hepatitis B core antigen-reactive blood donors in Quebec with an in-house nucleic acid testing assay

BACKGROUND

Hepatitis B virus (HBV) infection can be detected in blood donations by many serologic markers. Since the introduction of routine anti-hepatitis B core antigen (HBc) donor screening at Héma-Québec in April 2003, a large number of donors have been deferred on the basis of reactive anti-HBc test results. The objective of this study was to evaluate the correlation between the anti-HBc-reactive donations and the detection of HBV DNA with an in-house nucleic acid testing (NAT) assay.

STUDY DESIGN AND METHODS

The in-house HBV NAT assay is a conventional polymerase chain reaction amplifying part of the viral S gene. From October 2004 to November 2005, a total of 1169 anti-HBc-reactive donations were tested with this in-house assay. The results were correlated with hepatitis B surface antigen (HBsAg) and anti-HBs markers. HBV DNA-positive samples were further investigated by DNA sequencing.

RESULTS

All HBsAg-positive samples were detected by the NAT assay. Overall, 38 (3.25%) of anti-HBc-positive samples were found to be positive for the presence of HBV DNA. Of these 38, a total of 12 donations with a low level of HBV DNA were HBsAg-negative. The sequencing results clearly showed various genotypes and subtypes within a same genotype.

CONCLUSION

The 3.25 percent HBV DNA positivity rate among the anti-HBc-reactive donations and more particularly the low level of HBV DNA observed in occult donations underline the importance of the use of a sensitive assay to detect HBV DNA in conjunction with other markers. The HBV genetic diversity found in our donor population reflects the province demographics, particularly in the Montreal area where most of the positive donors were from.

Serological markers and risk factors for hepatitis B and C viruses in patients infected with human immunodeficiency virus

Both hepatitis B and hepatitis C viruses (HBV and HCV) infection are common in HIV-infected individuals as a result of shared risk factors for acquisition. A serological study for HBV and HCV was performed in 251 HIV-positive individuals from Medellín, Colombia. A qualitative RT-PCR for HCV was done in 90 patients with CD4+ T-cell count < 150 per mm(3). Serological markers for HBV infection were present in 97 (38.6%) patients. Thirty six of them (37.1%) had isolated anti-HBc. A multivariate analysis indicated that the following risk factors were significantly associated with the presence of these markers: age (OR = 1.05, 95% CI: 1.01-1.08), pediculosis pubis (OR = 1.83, 95% CI: 1.01-3.33), men who have sex with men and women (OR = 3.23, 95% CI: 1.46-7.13) and men who have sex only with men (OR = 3.73, 95% CI: 1.58-8.78). The same analysis restricted to women showed syphilis as the only significant risk factor. Thus, HBV infection was considerably associated with high risk sexual behavior. HCV was present in only two (0.8%) of HIV patients. Both of them were positive by RT-PCR and anti-HCV. This low frequency of HIV/HCV coinfection was probably due to the uncommon intravenous drug abuse in this population. The frequent finding of isolated anti-HBc warrants molecular approaches to rule out the presence of cryptic HBV infection.

[The histopathologic and clinical analysis of viral chronic hepatitis patients with negative serological viral markers]

OBJECTIVE

To analyze the histopathological and clinical features of viral chronic hepatitis patients with negative serological viral markers.

METHODS

62 hepatitis patients with negative serological markers were assayed with serological viral hepatitis markers, liver function test and liver biopsies were enrolled in the study. Serum HBV DNA of HBV cases was analyzed by PCR. Liver specimens were examined by immunohistochemistry for HBsAg and HBcAg.

RESULTS

The fit rate of histopathological diagnosis with clinical diagnosis is 53.2%, the fit rate is 69.1% in moderate chronic hepatitis group. The immunohistochemistry showed that HBsAg and/or HBeAg positive rate was 45.2%, 53.6% had moderate chronic hepatitis and 25% had mild hepatitis. 13 (46.4%) had G1 hepatitis, 10 (35.7%) had G2 hepatitis, 3 (10.8%) had G3 hepatitis and 2 (7.1%) had G4 hepatitis, and serum HBV DNA positive rate was 35.7%. There were no differences in HBV DNA levels between different hepatitis group and fibrosis stage group (P > 0.05). There were no differences in all indexes between HBV DNA negative group and HBV DNA positive group (P > 0.05). There were no differences in all indexes between HBV patients and other patients (P > 0.05).

CONCLUSION

Occult HBV infection may account for a high proportion of the cases with chronic hepatitis of unknown etiology. Most patients are chronic mild hepatitis, but they still have HBV replication and can progress to liver cirrhosis. Serum PCR test, liver biopsy and immunohistochemistry are helpful for the diagnosis.

[Establishment of a new combined enzyme immunoassay for detection of HBV preS1 and core antigens and the consistency with HBV DNA test]

In this study, a new combined enzyme immunoassay(NRAg ELISA) for detection of HBV PreS1 and core antigens which was highly consistent with serum HBV DNA test was established. The serial serum dilution test indicated that the average sensitivity of the assay was 10(3.2) genome copies/mL (95% CI: 10(2.2-4.2) genome copies/mL), which was notably higher than the test performed on Pre S1 or core antigen alone. The test with sera from 994 blood donors whose HBsAg were negative demonstrated that the specificity of this assay was 99.7% (95% CI: 99.1%-99.9%). 271 serum samples from chronic hepatitis patients were also examined and the result showed that the total consistent rate between NRAg ELISA and HBV DNA was 96.3% (95% CI: 93.3%-98.2%). The NRAg ELISA S/CO(signal/cutoff) was closely correlated with HBV genome copies (R = 0.9158, n=231). Furthermore,by using this assay,we found a patient whose HBsAg was negative but HBV DNA was positive. Sequencing result showed that HBV genome from this patient had a point mutation in the "a"epitope of S gene. Our results indicate that HBV NRAg ELISA has a high relativity with HBV DNA test, and can effectively detect the mutation of HBsAg,it is expected to be a potent tool for screening HBsAg mutant and is a convenient method for substituting HBV DNA test.

Administration of hepatitis B vaccine in winter as a significant predictor of the poor effectiveness of vaccination in rural Mongolia: evidence from a nationwide survey

BACKGROUND

Universal hepatitis B (HB) immunisation is the most effective means for prevention of hepatitis B virus (HBV) infection worldwide. Maintaining the vaccine cold chain is an essential part of a successful immunisation programme. Our recent nationwide survey in Mongolia has observed significant urban-rural differences in the prevalence of HBV infection among vaccinated cohorts.

OBJECTIVE

To examine whether the administration of HB vaccine in winter contributes to these residential discrepancies on the effectiveness of vaccination.

DESIGN AND SETTING

In 2004, a nationwide serosurvey was carried out covering both urban and rural areas of Mongolia. Sampling was multistage, with random probability from all public schools in the country.

PARTICIPANTS

A random sample of 1145 children (51.7% boys; aged 7-12 years), representative of Mongolian elementary school children.

RESULTS

Multivariate logistic regression analysis identified that total (past and current) HBV infection (OR 2.31, 95% CI 1.20 to 4.42; p = 0.012) was independently associated with the administration of all HB vaccines in winter. An increased OR for current HBV infection was also observed (OR 2.58, 95% CI 0.87 to 7.68; p = 0.089), but without significance. Interestingly, after stratifying by residence, the association between winter vaccination and total HBV infection was evident for rural (p = 0.008) but not for urban areas (p = 0.294). The frequency of vaccine-induced immunity was significantly (p = 0.007) lower for those who received HB vaccine at birth during winter in rural areas.

CONCLUSION

Administration of HB vaccine during winter is an important predictor of the low effectiveness of vaccination in rural Mongolia. To improve the effectiveness of HB vaccination in remote areas, cold chain control should be addressed with particular attention to the winter season.

Efficacy of lamivudine therapy in elderly patients with chronic hepatitis B infection

BACKGROUND

The aim of this study was to evaluate the efficacy of lamivudine therapy in elderly patients with chronic HBV infection.

METHODS

Patients aged >or=60 years (n = 40) received lamivudine monotherapy between February 1995 and September 2005 at Toranomon Hospital. We compared the efficacy of lamivudine therapy in these patients and in 639 patients aged <60 years, including 80 patients aged <60 years matched for sex, hepatitis B e antigen (HBeAg) status, and hepatitis B virus (HBV) DNA level.

RESULTS

The rates of normalization of alanine aminotransferase (ALT) level in 40 patients aged >or=60 years and 639 patients aged <60 years were 85% versus 76%, and 86% versus 73% at 1 and 3 years, respectively. The respective rates of loss of HBV-DNA were 74% versus 74%, and 76% versus 68% at 1 and 3 years. The respective cumulative emergence rates of the YMDD mutant were 16% and 17% at 1 year, and 46% and 49% at 3 years. In 80 patients <60 years old matched for sex, HBeAg status, and HBV-DNA level, the rates of normalization of the ALT level and loss of HBV-DNA were similar to those in the 639 patients aged <60 years. The emergence rate of YMDD mutants in patients aged >or=60 years were similar to those in matched patients aged <60 years. Multivariate analyses identified low serum bilirubin (<1 mg/dl) as an independent factor associated with the emergence of the YMDD motif mutation in patients aged >or=60 years.

CONCLUSIONS

Our results suggest that treatment with lamivudine is both well tolerated and efficacious in elderly patients with chronic HBV infection.

Diagnosis, diagnostic tests and monitoring of hepatitis B virus in monoinfected and HIV-coinfected patients

With the recent approval of several drugs for the management of chronic hepatitis B, the proper diagnosis and classification of this disease is necessary to determine if therapy is needed and what the best treatment options are. The diagnosis of chronic hepatitis B relies on serological testing, and disease stage is further characterized with HBV DNA levels and an assessment of liver disease through biopsy or non-invasive methods. A regular screening protocol is necessary for patients with chronic hepatitis B to monitor the development of cirrhosis and hepatocellular carcinoma. Patients receiving treatment also need regular monitoring for response to determine if a different therapeutic regimen is needed or if drug-resistant variants are being selected. This review discusses the various tests for hepatitis B diagnosis and for monitoring disease progression and treatment response. In addition, noninvasive methods for classifying liver disease stage are discussed, as are special considerations that are needed for individuals coinfected with HIV.

Virological features of hepatitis B virus-associated nephropathy in Japan

Hepatitis B virus (HBV)-associated nephropathy is considered as an immune-mediated disorder which is dependent on interactions between viral, host, and environmental factors. But there are few reports that investigated the relationship between the development of HBV-associated nephropathy and HBV genotypes and the mutations. To clarify the relationship between nephropathy and HBV genotype in Japan, six male patients with HBV-associated nephropathy were examined. The complete genome sequences of HBV were determined directly and the specific mutations associated with the development of HBV-associated nephropathy were examined by comparison of the alignments along with consensus sequences [HBV/A1 (Aa), A2 (Ae), B1 (Bj), B2 (Ba), C1 (Cs) and C2 (Ce)] retrieved from international database. The mean age of the six patients was 33.5 years. HBeAg was found in all patients and serum HBV-DNA levels were relatively high. Histological findings of renal tissues indicated five cases of membranous nephropathy and one membranoproliferative glomerulonephritis. HBV genotypes from the six patients were two HBV/A1, two A2 and two C2, suggesting HBV/A was predominant. G1862T mutation was observed in the two HBV/A1 patients, resulting in the pre-core amino acid substitution with a switch from valine (Val) to phenylalanine (Phe). Only one patient had core deletions. It is concluded that HBV/A may be associated with membranous nephropathy, but little relationship between HBV gene mutations and the development of HBV-associated nephropathy was observed.

[Hepatitis B in children with cancer]

INTRODUCTION

Cancer patients can be asymptomatic carriers of the hepatitis B virus (HBV), which can be reactivated by chemotherapy. Our aim was to identify the serological markers of HBV in children with cancer who were asymptomatic carriers of the virus. Fifty two (52) children with cancer treated at the Maracaibo University Hospital in Venezuela were studied, 28 of these children (53.8%) were HBV positive, despite no clinical or biochemical signs or symptoms of hepatitis. The type of serological markers present in each of these children.were investigated. We found 7 cases (25%) with hepatitis B surface antigen (HBsAg) and 2 (7.1%) with anticore as the only markers. Multiple markers were found in the other children: 9 (32.1%) HBsAg and anticore; 7 (25%) HBsAg, e-antigen (HBeAg) and anticore; 3 (10.7%) HBsAg, HBeAg antibody and anticore. In total, of the 28 positive children 20 (71.4%) showed positive anticore and of these 4 (20%) were of the IgM type. Our results show a high level of positivity for HBV in the children with cancer studied. In spite of being asymptomatic carriers of the HBV, it is noticeable the presence of serological markers for acute disease. We recommend testing for HBV serological markers before starting chemotherapy. Should the test results be negative, vaccination is indicated and should they be positive, specialized care is indicated.

Nationwide hepatitis B vaccination program in Taiwan: effectiveness in the 20 years after it was launched

The national hepatitis B vaccination program in Taiwan is considered one of the most successful and effective public health programs to control chronic hepatitis B infection in the past 20 years. This review illustrates how to implement a successful hepatitis B vaccination program based on Taiwan's experience. Several important controlled randomized clinical trials on hepatitis B immunoglobulin and vaccine in Taiwan demonstrated an 80-90% protective effect among infants of mothers who were positive for either hepatitis B envelope antigen or hepatitis B surface antigen. A series of prevalence surveys on children born before and after the national vaccination program began disclosed a steady decrease in seroprevalence of hepatitis B surface antigen in Taiwan, with 78-87% effectiveness after the national vaccination program was launched. Studies on the secular trend of liver disease risk also documented a 68% decline in mortality from fulminant hepatitis in infants and a 75% decrease in the incidence of hepatocellular carcinoma in children 6-9 years of age after the national vaccination program began. In conclusion, since 1984, the national hepatitis B vaccination program has been successful in preventing acute and chronic liver diseases in Taiwan.

Seroepidemiology of hepatitis A, B, C, and E viruses infection among preschool children in Taiwan

Taiwan was a hyperendemic area for hepatitis A and B viruses (HAV and HBV) infection before late 1980s. To study the seroprevalence of hepatitis A, B, C, and E viruses (HCV and HEV) infection among preschool children in Taiwan, a community-based survey was carried out in 54 kindergartens in 10 urban areas, 10 rural areas, and 2 aboriginal areas randomly selected through stratified sampling. Serum specimens of 2,538 preschool children were screened for the hepatitis A, C, and E antibodies by a commercially available enzyme immunoassay and for HBV markers by radioimmunoassay methods. The multivariate-adjusted odd ratios (OR) with their 95% confidence intervals (CI) were estimated through the multiple logistic regression analysis. Females had a statistically significantly higher HAV seroprevalence than males. The seroprevalence of HCV infection increased significantly with age. The larger the sibship size, the higher the seroprevalence of HBV infection. Aboriginal children had a significantly higher seroprevalence of HBV and HEV infection and lower seroprevalence of HCV infection than non-aboriginal children. A significantly higher seroprevalence of HBV infection was found in rural children than urban children. There was no significant association between serostatus of HAV and HEV infection and between serostatus of HBV and HCV infection among preschool children in Taiwan. The poor environmental and hygienic conditions in the aboriginal areas might play a role in infection with HBV and HEV.

[Clinical features and treatment of hepatic tumor-like lesions]

BACKGROUND & OBJECTIVE

Focal nodular hyperplasia (FNH), inflammatory pseudotumor (IPT), adenomatous nodular hyperplasia (ANH), and focal fatty change (FFC) are common hepatic tumor-like lesions, a group of benign liver diseases, which remains difficult to be distinguished from primary liver cancer (PLC). This study was to investigate the clinical features and treatment of these 4 kinds of hepatic tumor-like lesions.

METHODS

Clinical data of 70 patients with pathologically conformed hepatic tumor-like lesions, treated in Cancer Center of Sun Yat-sen University from 1992 to 2004, were studied retrospectively.

RESULTS

Of the 70 patients, 34 (48.6%) had clinical symptoms, and most of them suffered mild pain in the abdomen; 22 (31.4%) were positive for hepatitis B virus (HBV) antigen; 21 had mild abnormal liver function; 6 had alpha fetal protein (AFP) > 25 microg/L. The ultrasonography and computed tomography (CT) presentations of the tumor-like lesions were various. Only 8 cases of FNH were diagnosed preoperatively. Sixty-one patients received resection, with no postoperative complication occurred. One case of FNH and 1 case of IPT were recurred during follow-up, and treated with non-resection therapy.

CONCLUSIONS

Hepatic tumor-like lesions are difficult to be distinguished from PLC. Exploratory operation should be performed in cases suspicious of PLC.

Combined lamivudine/interferon-alpha treatment in "immunotolerant" children perinatally infected with hepatitis B: a pilot study

OBJECTIVE

To investigate whether combining the antiviral effect of lamivudine with the immune-boosting action of interferon-alpha (IFN-alpha) is effective in treating hepatitis B virus (HBV) "immunotolerant" children.

STUDY DESIGN

Twenty-three children (8 boys; mean age, 10 years) infected during the first year of life (17 Asian, 21 with normal aminotransferase levels, 15 with HBV-DNA >1000 pg/mL by hybridization and all with mild histologic changes) were treated with lamivudine (3 mg/kg) for 8 weeks alone and then lamivudine (3 mg/kg) and IFN-alpha (5 MU/m(2), 3 times weekly) in combination for 10 months.

RESULTS

Seventy-eight percent became HBV-DNA negative at the end of treatment, 5 (22%) seroconverted to anti-HBe, 4 (17%) of whom achieved complete viral control, becoming persistently HBsAg negative and anti-HBs positive. None had YMDD mutations. The viral status of the patients has not changed after a median follow-up of 40 months (range, 36 to 48).

CONCLUSIONS

This pilot study suggests that lamivudine pretreatment followed by a combination of lamivudine and IFN-alpha can induce complete viral control in HBV immunotolerant children, hitherto considered poor responders.

Impact of Presence of HBs Antigen and Anti-Hepatitis C Virus and Anti-Cytomegalovirus Antibodies on Transplanted Kidney Survival

INTRODUCTION

Infections are one of the most common complications after organ transplantation. Viral infections such as hepatitis type B (HBV) and C (HCV) or cytomegalovirus (CMV) infections are among the most serious ones. A high frequency of HBV and HCV infections has been recognized in kidney recipients. Viral infections play a special role in graft recipients because of clinical symptoms influencing graft function and recipient survival. Immunosuppressive treatment to decrease immunological reactions after organ transplantation may increase the risk of viral infections. The aim of this study was to evaluate the impact of the presence of HBs antigen and HCV and CMV antibodies on patient and graft survivals.

MATERIAL AND METHODS

Two hundred one enrolled kidney transplantation patients (96 women and 105 men) were treated with the same immunosuppressive regimen. Age, sex, and viral state (HBs antigen, anti-HCV and anti-CMV antibodies) were evaluated in every patient. Statistical analysis was performed with the Gompertz model, Kaplan-Meier curves and Cox proportional hazard tests.

RESULTS

The presence of HBs antigen was detected in 161 patients (20.4%), HCV antibodies in 61 recipients (30.3%); and CMV antibodies in 12 patients (5.9%). Eighty-seven recipients (43.4%) were seronegative. Average recipient age was 38.5 years.

CONCLUSION

Time of graft function was independent of the presence of HBs antigen or HCV or CMV antibodies.

Evaluation of liver tissue by polymerase chain reaction for hepatitis B virus in patients with negative viremia

AIM: To assess the clinical significance of Hepatitis B virus (HBV) DNA localization in the liver tissue of patients with positive HBsAg and negative viremia.

METHODS: HBV virological parameters of 33 HBsAg positive chronic hepatitis patients, including seromarkers and HBV DNA amplification in both sera and liver biopsies, were evaluated.

RESULTS: Ten patients had negative viremia and positive HBV DNA in their liver biopsies. Most of them had HBeAg-negative/HBeAb-positive chronic hepatitis. Their liver biochemical and histopathological profiles were different from the viremic patients. Their disease pattern was designated as “hepatitis B in situ”.

CONCLUSION: Hepatitis B in situ is a consequential entity which can be missed in clinical practice. It is a new clinical pattern of chronic HBV infection that considers HBV in liver biopsy and adds a new indication for antiviral therapy.

Simultaneous determination of HIV antibodies, hepatitis C antibodies, and hepatitis B antigens in dried blood spots--a feasibility study using a multi-analyte immunoassay

HIV in particular, as well as hepatitis B and C, present a burden on healthcare systems worldwide. Early detection of these diseases may prevent further infections and improve the outcome for patients. In particular, transmission of HIV from mother to child can be significantly reduced when preventive measures are taken before birth. We have developed and optimized a method for the simultaneous detection of HIV 1 and hepatitis B and C from dried blood specimens using the Luminex multi-analyte profiling technology (LabMap). Dried blood spots provide a convenient method for mailing, analysis and storage of samples. Specimens from known HIV-positive children (n=46) as well as hepatitis B- (n=8) and hepatitis C-positive patients (n=7) tested positive in our assay. Storage for up to 10 years did not interfere with the test in the case of HIV-positive patients. Results for five different antibodies and one antigen were obtained in approximately 80 seconds. Furthermore, antibody levels in infants of HIV-positive mothers were monitored over a period of 1 year. Antibodies were no longer detectable after 260-360 days, which compared well with results independently obtained by ELISA and Western blot analysis. We demonstrated the feasibility of the simultaneous detection of infectious diseases from dried blood. Our novel method also provides a convenient tool for monitoring children from HIV-positive mothers and for possible screening efforts.

The changing pattern of hepatitis B virus infection over the past three decades in Italy

By the end of 1970s, Italy was a country at medium endemic level of hepatitis B virus infection, with wide geographical differences; intrafamily transmission was the major mode by which infection spread; hepatitis B e antigen positivity and hepatitis Delta positivity were frequently detected in hepatitis B surface antigen chronic carriers; a high proportion of subjects with chronic liver disease resulted as hepatitis B surface antigen positive. Three decades apart, the picture was completely changed, as documented by several surveys. Nowadays, Italy is a country at very low endemic level of hepatitis B, without geographical differences; the infection is mostly sexually transmitted; hepatitis B e antigen positivity and hepatitis Delta positivity are rarely detected in hepatitis B surfaces antigen chronic carriers; a low proportion of subjects with chronic liver disease result hepatitis B surface antigen positive. These important changes may be due to both non-specific (i.e. improvement in socio-demographic features) and specific (i.e. a comprehensive vaccination program against hepatitis B) preventive measures.

An economic evaluation of universal infant vaccination strategies against hepatitis B in Thailand: an analytic decision approach to cost-effectiveness

To evaluate the cost-effectiveness of four infant vaccination strategies aimed at protecting the Thai population against hepatitis B virus (HBV) infection, vaccination and giving hepatitis B immunoglobulin (HBIg) to high-risk infants were compared with universal vaccination of infants and no vaccination. An analytic decision model was used to estimate the clinical and economic consequences of HBV for a hypothetical cohort of newborns for each of the immunization strategies. The model focused on the numbers and the costs of cases prevented. The decision model examined four different HBV management strategies: 1. screening for HBsAg, and vaccination; 2. screening for HBsAg, then HBeAg, and vaccination; 3. universal vaccination of all neonates; and 4. no vaccination. The cost-effectiveness per case prevented for Strategy 1 was 292.79 baht; for Strategy 2, 264.34 baht; for Strategy 3, 151.05 baht; and for Strategy 4, 0 baht. The incremental cost comparing Strategy 3 to Strategy 4 was 6,521 baht; comparing Strategy 2 to Strategy 3, 20,000 baht; and comparing Strategy 1 to Strategy 2, 95,000 baht. There is no socially acceptable threshold value for cost per case prevented to guide decisions on funding health care interventions. Strategy 3 should certainly be continued. Nevertheless, based on these results, Strategy 2 may be considered, despite the incremental cost being about 2 times that of Strategy 3, as it might represent a worthwhile investment of public funds.