Impaired response to hepatitis B vaccine in children receiving anticancer chemotherapy

Hepatitis B Reactivation and Vaccination Effectiveness after Solid Organ Transplantation: A Matched Case-Control Study

Solid organ transplant (SOT) recipients are at significant risk of hepatitis B (HB) virus (HBV) reactivation (HBVr). Despite the clinical significance of HBVr after solid organ transplantation, data on the risk factors for HBVr and vaccine effectiveness in SOT recipients with resolved HBV infection are limited. This study evaluated the risk factors for HBVr and the seroconversion rates after HBV vaccination in SOT recipients. Patients who had undergone solid organ transplantation and those with a resolved HBV infection were identified. We matched patients who experienced post-transplantation HBVr with those who did not. We also explored the characteristics and seroconversion rates of HBV-vaccinated patients following transplantation. In total, 1299 SOT recipients were identified as having a resolved HBV infection at the time of transplantation. Thirty-nine patients experienced HBVr. Pre-transplant HB surface antibodies (anti-HBs) positivity and allograft rejection within 3 months after transplantation were independently associated with HBVr. Among the 17 HBV-vaccinated patients, 14 (82.4%) received three or fewer vaccine doses, and 13 (76.5%) had seroconversion with positive anti-HBs results. Pre-transplant anti-HBs(-) status and allograft rejection were risk factors for HBVr in SOT recipients with a resolved HBV infection, and HBV vaccination after transplantation resulted in a high rate of anti-HBs seroconversion. HBV vaccination after transplantation should be considered to reduce the HBVr risk.

Advances in treatment and prevention of hepatitis B

Chronic hepatitis B (CHB) continues to contribute to worldwide morbidity and mortality significantly. Scientists, clinicians, pharmaceutical companies, and health organizations have dedicated substantial Intellectual and monetary resources to finding a cure, increasing immunization rates, and reducing the global burden of CHB. National and international health-related organizations including the center for disease control, the national institute of health, the American Association for the study of liver disease (AASLD), The European association for the study of the Liver (EASL), The Asia Pacific association for the study of the Liver (APASL) and the world health organization release periodic recommendations for disease prevention and treatment. Our review of the most recent guidelines by EASL, AASLD, APASL, and Taiwan Association for the Study of the Liver revealed that an overwhelming majority of cited studies were published before 2018. We reviewed Hepatitis B-related literature published 2018 onwards to identify recent developments and current barriers that will likely direct future efforts towards eradicating hepatitis B. The breakthrough in our understanding of the hepatitis B virus life cycle and resulting drug development is encouraging with significant room for further progress. Data from high-risk populations, most vulnerable to the devastating effects of hepatitis B infection and reactivation remain sparse. Utilization of systems approach, optimization of experimental models, identification and validation of next-generation biomarkers, and precise modulation of the human immune response will be critical for future innovation. Within the foreseeable future, new treatments will likely complement conventional therapies rather than replace them. Most Importantly, pragmatic management of CHB related population health challenges must be prioritized to produce real-world results.

High Risk of HBV Infection Among Vaccinated Polytransfused Children With Malignancy

AIM OF THE STUDY

The national Egyptian hepatitis B virus (HBV) vaccination program coverage of all infants started in 1992. The study aimed to assess immunity against HBV and occurrence of HBV breakthrough infections in vaccinated polytransfused children with malignancies.

PATIENTS AND METHODS

Eighty-nine polytransfused children with malignancies were recruited; 37 were on chemotherapy (male:female 20:17; mean age 7.7±4.0 y), and there were 52 naive patients (male:female 31:21; mean age 7.6±3.2 y). In addition, 162 age-matched and sex-matched healthy controls were recruited. Patients' sera were tested for quantitative anti-hepatitis B surface (HBs) (enzyme-linked immunoassays technique), hepatitis B surface antigen (HBsAg), total anti-hepatitis B core, and HBV-DNA (nested polymerase chain reaction for surface, core, and x-regions).

RESULTS

There was a significant lower percentage of having protective anti-HBs (10 to 100 IU/L) level among those receiving chemotherapy (13.5%) than those without (44.2%) and controls (32.1%). Twenty-one (67.7%) of those on chemotherapy were HBsAg positive compared with 10 (32.2%) of those without. Overall, 46 patients were HBV-DNA positive; 38 were c-region positive, 5 were s-region positive, 2 positive for the c-region and the s-region, and 1 tested positive for the c-region and the x-region. Of 46 patients, 20 were also positive for HBsAg (overt infection), while 26 had occult HBV infection (HBsAg-negative). Anti-HBs ≥10 IU/L co-existed among 45% of patients with overt infection and in 50% of those with occult infection. There was nonsignificant impact of receiving chemotherapy on the level of HBV-DNA.

CONCLUSIONS

Vaccinated children with malignancies, especially those under chemotherapy, are at a significant risk of HBV infection. The co-existence of anti-HBs with HBsAg and/or HBV-DNA may represent a possible residual transfusion-transmission risk with mutant HBV strains.

A Study of Immunogenicity of Intensified Hepatitis B Vaccination in Children Being Treated for Acute Lymphoblastic Leukemia

Children with acute lymphocytic leukemia (ALL) are at an increased risk of acquiring hepatitis B infection due to repeated exposure to blood products. They have poor response to vaccination due to immunosuppressive effects of malignant disease and chemotherapy; hence necessitating vaccination with increased doses or increased amount of vaccine or both. The authors studied 44 patients (32 boys and 12 girls) given double dose hepatitis B vaccination at 0, 1 and 2 mo during induction and consolidation phase of therapy. Of the thirty patients who completed the study, only 13 (43.34%) developed protective antibody levels (titres >10 mIU/ml) measured 4 wk after the third dose. The authors conclude that with three double dose schedule of Hepatitis B vaccination, response rate is poor. Therefore, for protection from Hepatitis B infection during initial phase of therapy, there is a need to provide passive immunization.

Prevention of Hepatitis B Virus Infection in the United States: Recommendations of the Advisory Committee on Immunization Practices

HEPATITIS B VIRUS (HBV) IS TRANSMITTED VIA BLOOD OR SEXUAL CONTACT. PERSONS WITH CHRONIC HBV INFECTION ARE AT INCREASED RISK FOR CIRRHOSIS AND LIVER CANCER AND REQUIRE MEDICAL CARE. THIS REPORT UPDATES AND SUMMARIZES PREVIOUSLY PUBLISHED RECOMMENDATIONS FROM THE ADVISORY COMMITTEE ON IMMUNIZATION PRACTICES (ACIP) AND CDC REGARDING THE PREVENTION OF HBV INFECTION IN THE UNITED STATES. ACIP RECOMMENDS TESTING ALL PREGNANT WOMEN FOR HEPATITIS B SURFACE ANTIGEN (HBSAG), AND TESTING HBSAG-POSITIVE PREGNANT WOMEN FOR HEPATITIS B VIRUS DEOXYRIBONUCLEIC ACID (HBV DNA); ADMINISTRATION OF HEPB VACCINE AND HEPATITIS B IMMUNE GLOBULIN (HBIG) FOR INFANTS BORN TO HBV-INFECTED WOMEN WITHIN 12 HOURS OF BIRTH, FOLLOWED BY COMPLETION OF THE VACCINE SERIES AND POSTVACCINATION SEROLOGIC TESTING; UNIVERSAL HEPATITIS B VACCINATION WITHIN 24 HOURS OF BIRTH, FOLLOWED BY COMPLETION OF THE VACCINE SERIES; AND VACCINATION OF CHILDREN AND ADOLESCENTS AGED <19 YEARS WHO HAVE NOT BEEN VACCINATED PREVIOUSLY. ACIP RECOMMENDS VACCINATION OF ADULTS AT RISK FOR HBV INFECTION, INCLUDING UNIVERSAL VACCINATION OF ADULTS IN SETTINGS IN WHICH A HIGH PROPORTION HAVE RISK FACTORS FOR HBV INFECTION AND VACCINATION OF ADULTS REQUESTING PROTECTION FROM HBV WITHOUT ACKNOWLEDGMENT OF A SPECIFIC RISK FACTOR. THESE RECOMMENDATIONS ALSO PROVIDE CDC GUIDANCE FOR POSTEXPOSURE PROPHYLAXIS FOLLOWING OCCUPATIONAL AND OTHER EXPOSURES. THIS REPORT ALSO BRIEFLY SUMMARIZES PREVIOUSLY PUBLISHED AMERICAN ASSOCIATION FOR THE STUDY OF LIVER DISEASEST GUIDELINES FOR MATERNAL ANTIVIRAL THERAPY TO REDUCE PERINATAL HBV TRANSMISSION.

The Immune Response of Vaccination Against Hepatitis B virus in Iranian Patients Undergoing Chemotherapy

Introduction:

Hepatitis B virus (HBV) infection and its complications are major public health problems. As it is hard to treat and control the chronic state, control of disease depends on the prevention especially by vaccination. There is an impaired immune response to vaccinations including HBV in patients with some malignancies. The aim of this study is to assess the response rate of patients undergoing chemotherapy to HBV vaccination.

Materials and Methods:

All patients from two hematology/oncology clinics in Isfahan, Iran with the history of at least 1 month chemotherapy who had the inclusion criteria were enrolled in a case control study. Also a sex- and age-matched control group from healthy population was selected. They were vaccinated in a schedule of 0, 1, and 6 months and were examined for antibody titers 1 month after the last dose. The titers more than 10 mIU/ml were determined as positive response to vaccination.

Results:

In this study, 50 patients and 50 healthy subjects were enrolled. The two groups were age and sex matched (P > 0.05). Frequency of negative responses to HBV vaccination in case and control groups were 9 (18%) and 1 (2%), respectively (OR = 10.75, CI = 1.30–88.47, P = 0.027). Of 50 patients, 54%, 12%, 22%, and 12% had breast cancer, lymphoma, gastrointestinal, and genitourinary cancers, respectively, and frequency of negative responses were 3 (11%), 1 (16%), 4 (36.4%), and 1 (16%), respectively (P = 0.167).

Conclusion:

According to our results, malignancy and chemotherapy will have an important effect on the immune system and cause negative response to HBV vaccination. Our results revealed the importance of passive immunity and screening for HBV infection in patients undergoing chemotherapy. Also more studies for better vaccination schedules in this group of patients are recommended.

[Seroconversion in response to a reinforced primary hepatitis B vaccination in children with cancer]

INTRODUCTION

Immune response against vaccine antigens may be impaired in children with cancer. The aim of this study was to evaluate the seroconversion response against hepatitis B vaccination (HBV) at the time of chemotherapy onset and/or remission in children with cancer.

PATIENTS AND METHOD

Prospective, two-centre, controlled, non-randomised study conducted on children recently diagnosed with cancer, paired with healthy subjects. Cases received HBV at time 0, 1 and 6 months with DNA recombinant HBV at a dose of 20 and 40 μg if < or > than 10 years of age, respectively, at the time of diagnosis for solids tumours and after the remission in case of haematological tumours. Controls received the same schedule, but at of 10 and 20 μg doses, respectively. HBs antibodies were measured in serum samples obtained at 2, 8 and 12 months post-vaccination. Protective titres were defined as > 10 mIU/ml at 8th month of follow up.

RESULTS

A total of 78 children with cancer and 25 healthy controls were analysed at month 8th of follow up. Seroconversion rates in the cancer group reached 26.9%, with no differences by age, gender or type of tumour (P = .13, .29, and .44, respectively). Control group seroconversion was 100% at the 8th month, with P < .0001 compared with the cancer group. At month 12 of follow up, just 31.9% of children with cancer achieved anti-HBs antibodies > 10 mIU/ml.

CONCLUSIONS

Vaccination against hepatitis B with three doses of DNA recombinant vaccine at an increased concentration, administrated at the time of onset of chemotherapy and/or remission provided an insufficient immune response in a majority of children with cancer. More immunogenic vaccines should be evaluated in this special population, such as a third generation, with more immunogenic adjuvants, enhanced schedules at 0, 1, 2, 6 month, evaluation of antibody titres at month 8 and 12h to evaluate the need for further booster doses.

Guidelines on vaccinations in paediatric haematology and oncology patients

OBJECTIVE

Vaccinations are the most important tool to prevent infectious diseases. Chemotherapy-induced immune depression may impact the efficacy of vaccinations in children.

PATIENTS AND METHODS

A panel of experts of the supportive care working group of the Italian Association Paediatric Haematology Oncology (AIEOP) addressed this issue by guidelines on vaccinations in paediatric cancer patients. The literature published between 1980 and 2013 was reviewed.

RESULTS AND CONCLUSION

During intensive chemotherapy, vaccination turned out to be effective for hepatitis A and B, whilst vaccinations with toxoid, protein subunits, or bacterial antigens should be postponed to the less intensive phases, to achieve an adequate immune response. Apart from varicella, the administration of live-attenuated-virus vaccines is not recommended during this phase. Family members should remain on recommended vaccination schedules, including toxoid, inactivated vaccine (also poliomyelitis), and live-attenuated vaccines (varicella, measles, mumps, and rubella). By the time of completion of chemotherapy, insufficient serum antibody levels for vaccine-preventable diseases have been reported, while immunological memory appears to be preserved. Once immunological recovery is completed, usually after 6 months, response to booster or vaccination is generally good and allows patients to be protected and also to contribute to herd immunity.

Hepatitis B immunity and response to booster vaccination in children with inflammatory bowel disease treated with infliximab

OBJECTIVES

Hepatitis B virus (HBV) reactivation has been described in patients treated with infliximab for inflammatory bowel disease (IBD). This has resulted in a "black box" warning. Although universal vaccination against hepatitis B was implemented in the United States in 1991, up to 10% of vaccine recipients fail to respond with adequate anti-hepatitis B surface antibodies (anti-HBs) levels after a primary series of vaccinations. In addition, anti-HBs levels are expected to decline with time. The objectives of this study were to determine HBV immunity in children with IBD on infliximab therapy and to determine response to a booster dose of the HBV vaccine in patients who were found to be non-immune.

METHODS

This was a prospective cross-sectional, single-center study that included 100 pediatric IBD patients on infliximab. Serologic specimens were tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), and anti-HBs. Patients with an anti-HBs level ≥10 mIU/ml were considered to be immune. One booster dose was given to non-immune patients and a serum sample was collected after 4 weeks to assess the presence of anamnestic response (anti-HBs level ≥10 mIU/ml after booster).

RESULTS

The mean age of the patients was 17.9 (±4.0) years. None of the patients were positive for HBsAg or anti-HBc. In all, 87 patients were vaccinated against HBV and 49/87 (56%) had immunity to HBV as defined by anti-HBs level ≥10 mIU/ml. The mean concentration of anti-HBs levels in immune patients was 295.6 (±350.6) mIU/ml. Older age, lower albumin levels, and the presence of pancolitis were associated with the absence of protective antibodies; however, infliximab dose, frequency, duration, and the concurrent use of immunomodulators were not significantly different between immune and non-immune patients. Thirty-four patients received booster immunization and 26/34 (76%) had an anamnestic response. Interestingly, non-responders were given infliximab with higher frequency (every 5.9 ± 1.2 weeks vs. every 7.1 ± 1.8 weeks, P=0.01). Overall, 75/87 (86%) of previously immunized patients were considered immune against HBV infection.

CONCLUSIONS

In pediatric IBD patients seen at a large, urban tertiary care facility in the United States, a significant minority (13%) have not been vaccinated against HBV. Nearly one-half of all patients (and 44% of previously vaccinated patients) did not have protective anti-HBs levels. Moreover, of those previously vaccinated, a significant minority (14%) appear at risk for HBV because protective anti-HBs levels were absent and could not be elicited through booster immunization. Given the high risk for severe HBV infection in this group, efforts should be made to screen for HBV immunity at the time of IBD diagnosis. Booster immunization should be considered in patients without protective antibodies.

Immune response to conjugated meningococcal C vaccine in pediatric oncology patients

BACKGROUND

Following outbreaks of meningococcal disease in Quebec in 1991-1993 and 2000-2001, a mass vaccination campaign was performed. In 2001-2002, children aged 2 months to 20 years were immunized with the Meningococcal CRM197 vaccine (Menjugate). We examined the response of pediatric oncology patients during or following maintenance chemotherapy and post-bone-marrow transplantation to Meningococcal C vaccine.

PROCEDURE

This was an open label descriptive study of a cohort of patients from the oncology clinic at the Montreal Children's Hospital. A positive vaccine response was defined as a fourfold increase in specific IgG from baseline and a bactericidal assay using human complement (hBCA) titer >1:4.

RESULTS

Of the 25 patients with ALL, 13 had a serologic response (average 60-fold increase). The serologic responders had a higher mean B cell count (0.262) compared to non-responders 0.068 x 10.9/L [t(23) = 2.843 (P < 0.05)]. Eleven of the 12 non-responders and 4 of the responders were on maintenance chemotherapy. In addition, two of the five patients post-bone-marrow transplant, responded. Fifteen of the 34 patients (44%) had an adequate hBCA response (mean titer 61). The group included 14/18 serologic responders with hBCA response (P < 0.001) and 16/17 non-serologic responders with no hBCA response (P < 0.001).

CONCLUSIONS

Meningococcal C-conjugate vaccine produced variable responses in children with common cancers. Proximity to chemotherapy and total B cell number may help predict likelihood of response.

Evaluation of vaccine dosing in patients with solid tumors receiving myelosuppressive chemotherapy

OBJECTIVE

To provide oncology healthcare providers with information on current vaccine recommendations and discuss the proper timing of vaccination in relation to chemotherapy, to allow for an adequate, protective antibody response.

DATA SOURCES

In this review, we have attempted to include all available literature as well as the current recommendations. The National Library of Medicine, PubMed online database was searched using the keywords: chemotherapy, influenza, vaccine, cancer, immunosuppression. In addition, the Center for Disease Control (CDC) guidelines were reviewed and incorporated into the recommendations.

DATA SYNTHESIS

There were several limitations to the literature available. To date, most of the literature was completed in the 1970s and 1980s, and definitions of protective immunity regarding influenza vaccines have changed over time, as well as improved study design. These studies have also been completed in a variety of disease states, hence, it is difficult to make comparisons between trials. The recommendations in this review are consistent with the current CDC Guidelines and, until further clinical trials are carried out, are the most conservative recommendations in favor of patient safety, health care costs, and resource utilization.

CONCLUSION

Patients on cancer chemotherapy should receive vaccination at least 2 weeks before initiation of treatment. Providers should avoid administering vaccination during chemotherapy or active radiation treatment because of suboptimal responses to vaccines. Active immunization has been shown to confer protective immunity to several infections in cancer patients at similar rates to healthy individuals.

Unexpected protection from infection by two booster hepatitis B virus vaccination in children with acute lymphoblastic leukemia

The protective power of two booster dose vaccination against hepatitis B virus (HBV) infection has not been previously studied in patients with acute lymphoblastic leukemia (ALL) who remained unresponsive to immunization. The aim of this study was to determine the HBV infection rate in vaccinated and unvaccinated patients with or without seroconversion and to compare these groups in respect to HBV infection rate. The study group included 111 male and 85 female ALL patients with a mean age of 6.23+/-4.10 years. Patients were divided into three groups as follows: Group 1 included 82 patients who were vaccinated during maintenance chemotherapy, Group 2 included 87 unvaccinated patients, and Group 3 included 27 patients who were vaccinated prior to the diagnosis of ALL. Seroconversion was obtained in 35.4% (29/82) of patients in Group 1. The incidence of HBV infection was significantly lower in Group 1 (4/82, 4.8%) than in Group 2 (25/87, 28.7%). When we compared only the seronegative patients in Group 1 with Group 2 in respect to HBV infection rate, Group 1 still had a significantly lower HBV infection rate than Group 2 (7.5% versus 28.7%) (p<0.001). No patients in Group 3 (n=27) had HBV infection. In addition to the seroconversion level, infection rate is also important in the evaluation of the effectiveness of vaccination. Our study results suggest that a high protective role of HBV vaccination was also observed in non-seroconversion ALL patients. The effect of cellular immunity on the protection against infection should also be investigated in such patients with further studies.

Association between cancer chemotherapy and canine distemper virus, canine parvovirus, and rabies virus antibody titers in tumor-bearing dogs

OBJECTIVE

To determine the association between cancer chemotherapy and serum canine distemper virus (CDV), canine parvovirus (CPV), and rabies virus antibody titers in tumor-bearing dogs.

DESIGN

Prospective study.

ANIMALS

21 client-owned dogs with various malignancies and 16 client-owned dogs with lymphoma.

PROCEDURE

In study A, serum antibody titers were measured by use of hemagglutination inhibition (CPV titers) or serum neutralization (CDV titers) before and at least 1 month after initiation of chemotherapy. Baseline values were compared with values obtained from a control population of 122 healthy dogs seen for routine revaccination. Titers were considered protective at > or = 1:96 for CDV and > or = 1:80 for CPV. In study B, serum IgG titers were measured by use of immunofluorescent assay (CDV and CPV titers) and rapid fluorescent focus inhibition test (RFFIT, rabies titers) at baseline and again at weeks 5, 8, and 24 of a standard chemotherapy protocol for treatment of lymphoma. An IgG titer of > or = 1:50 was considered protective for CPV and CDV. An RFFIT titer of > or = 0.5 U/ml was considered protective for rabies virus.

RESULTS

Significant changes were not detected in CDV, CPV, and rabies virus titers following chemotherapy in tumor-bearing dogs.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that established immunity to CDV, CPV, and rabies virus from previous vaccination is not significantly compromised by standard chemotherapy used to treat tumor-bearing dogs.

[Immunization for children treated for solid tumors: what are the guidelines?]

There is no agreement on immunization of children treated with chemotherapy (CT) for solid tumors. Based on a review of the literature, we have attempted to establish guidelines on this subject. Except for hepatitis B vaccine, there is no argument to support the use of vaccine during CT. After a standard CT, a 3-month washout period appears to be necessary before starting an immunization program for a child not previously vaccinated, or to proceed with the recommended booster injections for diphteria anatoxin, tetanus vaccine, poliomyelitis inactivated vaccine, pertussis vaccine, and haemophilus influenza type b vaccine if the child is less than 5 years old. For mumps, measles, and rubella live vaccines, a longer post-CT washout of 6 months is suggested for the initial immunization, or for a revaccination of a child proved to be negative for all three serologies. Following high-dose CT a minimal 12-months term and a normalization of the blood lymphocytes count is necessary before planning booster injections once having checked for antidiphteria, tetanic, polio, measles, mumps, rubella and +/- haemophilus antibody titles. We don't find any reason to recommend a systematic varicella immunization in pediatric oncology. Pneumococcal vaccine is recommended in case of asplenia. Any other vaccination (BCG, influenza, yellow fever) must be evaluated individually.

Efficacy of immunization against hepatitis B virus infection in children with cancer

BACKGROUND

The purpose of this study was to evaluate the impact of hepatitis B prophylaxis in preventing hepatitis B infection in children with malignancy.

PROCEDURE

Between May, 1993, and September, 1998, a total of 151 children (95 boys, 56 girls), 29 (19%) with lymphoma, 58 (39%) with leukemia, and 64 (42%) with solid tumor, were screened for hepatitis B virus (HBV). The mean age was 7. 5 +/- 2.5 years. Children with negative serology received active and/or passive immunization. HBsAg and anti-HBs were positive prior to vaccination in 16 (10%) and 17 (11%) children, respectively. One hundred eighteen children (78%) of one hundred fifty-one with negative serology were included in the vaccination program. The vaccine dose was 40 microg. Children with solid tumor and lymphoma received recombinant hepatitis B vaccine at diagnosis, repeated at months 1, 2, and 12. Hyperimmunglobulin was administered monthly in children with leukemia during the intensive chemotherapy period. They were then vaccinated following the third month of maintenance therapy with the schedule described above. Anti-HBs titers were measured every 3 months, and titers above 10 mlU/ml were accepted as protective.

RESULTS

Anti-HBs positivity after the first three doses was 77% in solid tumors, 88% in acute leukemia, and 48% in lymphomas. Anti-HBs positivity with respect to diagnosis in children completing the vaccination schedule was 94% in solid tumor, 90% in leukemia, and 74% in lymphoma (P > 0.05). Thirty-three percent of children have not received the fourth dose as yet. In total 78% of the children developed protective antibody titers with or without the fourth dose, and none was infected with HBV during 3 years of follow-up. Ten (39%) of twenty-six children who remained unresponsive to immunization were infected with HBV.

CONCLUSIONS

These data reveal that HBV prophylaxis is necessary and that our vaccination schedule is effective in preventing HBV infection in these children.

[Recommended vaccines and immunoglobulins for immunocompromised patients]

A revision of the literature was made as to the recommendations given for the use of vaccines and immune globulins in persons who presented total or partial immunodeficiency, mainly related to the nineties. The analysis of 75 references led to the following principal conclusions: the vaccines containing living agents are generally inappropriate for persons who present conditions which determine serious immunodeficiency; the vaccines which contain dead agents or only antigenic fractions, despite their being less immunogenic and conferring lower rates of protection to severely immunocompromised persons as compared to normal persons, are safe and should be administered to them. Immunocompromised patients should receive immune globulins for the same indications and in the same doses as immunocompetent persons, with the exception of immune globulin to prevent measles, as recommended in a dosage of 0.5 mL/Kg for immunodeficients (15 mL, maximum).

Hepatitis B vaccination in acute lymphoblastic leukemia

Active immunization against hepatitis B virus infection was carried out in 162 patients with acute lymphoblastic leukemia attending the Outpatient Department at Tata Memorial Hospital. Recombinant DNA vaccine was given in three doses at 0, 1 and 2 months followed by a booster 1 year after the first dose. Antibodies to hepatitis B surface antigen could be detected in 19.7% of patients following vaccination. Of these only 10.5% had titers in the protective range. Immunosuppression induced by both disease and treatment appears to diminish responsiveness to vaccination. Passive active prophylaxis with both vaccine and immunoglobulin may be a more effective alternative in these patients.