Factors Associated with Increased or Decreased Stress Level in French Children during the First COVID-19 Lockdown.

In spring 2020, governments of many countries implemented lockdown measures to prevent the spread of the COVID-19 pandemic. Worldwide, the pandemic forced about 1.5 billion children to stay at home for several weeks and to experience homeschooling. The objective of this study was to assess the variation in stress levels and associated factors in school-aged children in France during the first COVID-19 lockdown. A cross-sectional study using an online questionnaire was designed by an interdisciplinary team involving hospital child psychiatrists and school doctors. Between 15 June and 15 July 2020, Educational Academy of Lyon (France) invited the parents of school-aged children to participate in this survey. The first part of the questionnaire concerned the children with data on lockdown conditions, socio-demographic data, daily rhythms (eating and sleeping), perceived stress variations, and feelings. The second part assessed parental perspectives on their child's psychological state and use of the mental health care system. Multivariate logistic regression was performed to identify factors associated with stress variation (increased or decreased). A total of 7218 questionnaires were fully completed by children from elementary school to high school with a balanced sex ratio. In summary, 29% of children reported a higher stress level during the lockdown, 34% reported a lower stress level, and 37% reported no stress variation in the usual situation prior to COVID-19. Parents were most often able to identify signs of increased stress levels in their children. The most influential factors in the variation of stress for children were academic pressure, family relationships, and fear of being infected or infecting a family member with SARS-CoV-2. Our study underlines the high impact of school attendance stressors on children in usual conditions and encourages vigilance for children whose stress levels have decreased during the lockdown but who may have increased difficulty re-exposing themselves upon deconfinement.

A new approach to estimate vaccine efficacy based on immunogenicity data applied to influenza vaccines administered by the intradermal or intramuscular routes.

BACKGROUND: Despite their pivotal role in the assessment of influenza vaccines, limited attempts have been made to use haemagglutination inhibition (HI) titers for predicting vaccine efficacy against laboratory-confirmed influenza. We present here the second step of a two-step approach allowing performing such predictions and use it to compare a new trivalent inactivated influenza vaccine administered by the intradermal (ID) route (INTANZA® /IDFlu®) with the vaccine administered by the classical intramuscular (IM) route. METHODS: The first step corresponding to the estimation of the level of protection against laboratory-confirmed influenza that can be linked to each HI titer, referred to as the HI protection curve, was achieved by using a meta-analytical approach based on published information. Vaccine efficacy and differences in vaccine efficacy are predicted in a second step using this HI protection curve alongside the results of two randomized clinical trials providing comparative information on the immunogenicity of trivalent inactivated influenza vaccines administered ID or IM in 3503 & 1645 elderly participants, respectively. RESULTS: Pooling all available immunogenicity data, the predicted vaccine efficacy was 63.3% [CI: 58.1; 68.7] for ID route and 54.4% [CI: 49.4; 59.2] for IM route. The corresponding relative increase in efficacy that is of 16.5% [CI: 12.7; 20.1]. Predicted vaccine efficacies decreased with age for both vaccines, but the decrease was less marked by ID route: the relative increase in efficacy for subjects aged 70 years and above is of 18.0% [CI:12;24]. CONCLUSION: The analysis performed confirmed that the superior immune response provided by the vaccine using the ID route should translate into a higher vaccine efficacy against laboratory-confirmed influenza.

Perception and acceptance of intradermal influenza vaccination: Patient reported outcomes from phase 3 clinical trials.

An intradermal trivalent inactivated influenza vaccine administered using a microinjection system has received European marketing authorization from the European Medicine Agency. We assessed clinical trial subjects' perception of injection site reactions (ISRs) and whether ISRs affected overall acceptability of vaccination and willingness to be vaccinated in the future. A validated, self-administered, patient reported outcome questionnaire was completed 21 days after intradermal or intramuscular vaccination by elderly and non-elderly adult participants in two European randomized, controlled, open-label phase 3 trials. The questionnaire addressed: the acceptability of ISRs, effect of ISRs on arm movement or sleep, satisfaction with the injection system, and willingness to be revaccinated. Questions were answered using a 5-point Likert verbal rating scale (1 = most favourable, 5 = most unfavourable response). Mean scores were calculated per group. 5,305 questionnaires were completed and analysed (95% return rate). Mean scores were close to 1 in all cases (maximum 1.68), indicating an overall favourable opinion of the vaccination and ISRs. More than 96% of participants rated ISRs after intradermal or intramuscular vaccination as either 'totally acceptable' or 'very acceptable'. Willingness to get vaccinated the following year and satisfaction with the intradermal microinjection system or the conventional intramuscular syringe were high and were not adversely affected by ISRs. ISRs after intradermal influenza vaccine administered using a microinjection system are well accepted by the vaccinees and are generally not a cause for concern.

Immunogenicity, large scale safety and lot consistency of an intradermal influenza vaccine in adults aged 18-60 years: Randomized, controlled, phase III trial.

BACKGROUND: Vaccination is the most effective way of reducing the large health and economic burden of influenza, yet vaccination coverage remains low, particularly among non-elderly adults. Intradermal influenza vaccine produce an effective immune response and represents an alternative to intramuscular influenza vaccination. RESULTS: The three industrial lots of intradermal vaccine were equivalent in terms of post-vaccination titres elicited by day 21. The intradermal and intramuscular vaccines induced similar post-vaccination titres, and satisfied all three immunogenicity criteria set out in the European regulatory guidelines for influenza vaccines for each of the three influenza strains. The solicited systemic reaction profile and the incidence and type of spontaneously reported adverse events were similar in the two vaccine groups and in line with the known safety profile of inactivated influenza vaccines. Injection site reactions were more frequent with intradermal vaccination. METHODS: A Phase III multicentre, randomised, controlled, double-blind (for the three different lots of intradermal vaccine) study assessed lot-to-lot consistency, immunogenicity and safety of an intradermal inactivated trivalent splitvirion influenza vaccine in 2,255 adults aged 18-60 years. Participants received one of three lots of intradermal vaccine containing 9 microg of haemagglutinin per influenza strain, or a licensed intramuscular control vaccine containing 15 microg haemagglutinin/strain. CONCLUSIONS: This intradermal vaccine containing 9 microg per influenza strain, provides an alternative to conventional intramuscular vaccination, has a reliable production method and is equally immunogenic and well tolerated in adults. The study was registered at clinicaltrials.gov (identifier NCT00383539).

Intradermal influenza vaccination of healthy adults using a new microinjection system: a 3-year randomised controlled safety and immunogenicity trial.

BACKGROUND: Intradermal vaccination provides direct and potentially more efficient access to the immune system via specialised dendritic cells and draining lymphatic vessels. We investigated the immunogenicity and safety during 3 successive years of different dosages of a trivalent, inactivated, split-virion vaccine against seasonal influenza given intradermally using a microinjection system compared with an intramuscular control vaccine. METHODS: In a randomised, partially blinded, controlled study, healthy volunteers (1150 aged 18 to 57 years at enrollment) received three annual vaccinations of intradermal or intramuscular vaccine. In Year 1, subjects were randomised to one of three groups: 3 microg or 6 microg haemagglutinin/strain/dose of inactivated influenza vaccine intradermally, or a licensed inactivated influenza vaccine intramuscularly containing 15 microg/strain/dose. In Year 2 subjects were randomised again to one of two groups: 9 microg/strain/dose intradermally or 15 microg intramuscularly. In Year 3 subjects were randomised a third time to one of two groups: 9 microg intradermally or 15 microg intramuscularly. Randomisation lists in Year 1 were stratified for site. Randomisation lists in Years 2 and 3 were stratified for site and by vaccine received in previous years to ensure the inclusion of a comparable number of subjects in a vaccine group at each centre each year. Immunogenicity was assessed 21 days after each vaccination. Safety was assessed throughout the study. RESULTS: In Years 2 and 3, 9 microg intradermal was comparably immunogenic to 15 microg intramuscular for all strains, and both vaccines met European requirements for annual licensing of influenza vaccines. The 3 microg and 6 microg intradermal formulations were less immunogenic than intramuscular 15 microg. Safety of the intradermal and intramuscular vaccinations was comparable in each year of the study. Injection site erythema and swelling was more common with the intradermal route. CONCLUSION: An influenza vaccine with 9 microg of haemagglutinin/strain given using an intradermal microinjection system showed comparable immunogenic and safety profiles to a licensed intramuscular vaccine, and presents a promising alternative to intramuscular vaccination for influenza for adults younger than 60 years. TRIAL REGISTRATION: (Clinicaltrials.gov) NCT00703651.

Combined typhoid fever and hepatitis A vaccine: comparison of immunogenicity and safety to concomitant monovalent vaccine over 3 years.

BACKGROUND: The safety and immunogenicity of Viatim, a combined hepatitis A (HA) and typhoid fever (Vi) vaccine, were compared with the monovalent component vaccines up to and 1 month after a booster dose at 3 years. METHODS: Healthy, adult volunteers were randomized to receive Viatim (group A, n = 179) or separate HA and Vi vaccines (group B, n = 181); subgroups were boosted after 3 years with Viatim (groups C and D, n = 56 and 46, respectively). Local and systemic reactions were recorded for 28 days postvaccination. Seroconversion and seroprotection rates and geometric mean antibody concentrations were measured at 14 and 28 days, 1, 2, and 3 years postvaccination, and 28 days after the booster dose. RESULTS: Local and systemic safety profiles were equivalent between the two groups. Immediate local reactions were infrequent (1 in group A and 2 in group B). Local reactions, consisting mostly of mild or moderate pain, were least frequent with monovalent HA. Antibody concentrations to both antigens were similar in groups A and B, in which HA seroprotection rates (> or = 20 mIU/mL) were respectively, 98.7% and 100% at day 28, and 99.1% and 99.0% after 3 years, achieving 100% after the booster. Vi seroprotection rates (> or = 1 microg/mL) of 85.2% and 84.9% after 28 days fell to 32.1% and 35.6% after 3 years, increasing to 67.3% and 69.8% after the booster dose. CONCLUSIONS: The combined HA/Vi vaccine, Viatim, had equivalent tolerability and safety and was as rapidly immunogenic as its component monovalent vaccines when given concurrently. A booster dose after 3 years significantly increased antibody levels with some evidence of relative hyporesponsiveness of the typhoid response.

Intanza (®) 9 µg intradermal seasonal influenza vaccine for adults 18 to 59 years of age.

Seasonal influenza in healthy working-age adults accounts for a substantial part of the socioeconomic burden of this disease. Intanza® 9 µg (sanofi pasteur) is a microneedle-delivered intradermal trivalent inactivated influenza vaccine approved in 2009 for the prevention of seasonal influenza in adults 18 to 59 years of age. The microneedle system reliably and reproducibly delivers the vaccine to the dermis. Clinical studies show that Intanza 9 µg is as immunogenic and as well tolerated in working-age adults as a reference intramuscular trivalent inactivated vaccine. Local reactions to Intanza 9 µg, mainly erythema, are transient, mostly mild or moderate, and do not affect acceptability. Intanza 9 µg is considered satisfactory by at least 95% of both vaccinees and prescribers, especially because of the short needle and rapid administration. Because Intanza® 9 µg offers an alternative to intramuscular vaccines, it might help increase influenza vaccine coverage rates.

Immunogenicity and safety of Intanza(®)/IDflu(®) intradermal influenza vaccine in South Korean adults: a multicenter, randomized trial.

Intanza(®)/IDflu(®) (Sanofi Pasteur, Lyon, France) is an intradermal inactivated trivalent influenza vaccine developed as an alternative to intramuscular influenza vaccine. The objective of this study was to confirm the immunogenicity and safety of Intanza/IDflu in South Korean adults. In a phase IV multicenter trial, South Korean adults 18-59 y old (n = 120) and ≥ 60 y old (n = 120) were randomized 1:1 to receive a single dose of Intanza/IDflu (9 µg for 18-59 y, 15 µg for ≥ 60 y) or trivalent intramuscular vaccine (Vaxigrip(®) 15 µg, Sanofi Pasteur, Lyon, France). Blood was collected on pre-vaccination (day 0) and on day 21. Hemagglutination inhibition titers, seroprotection rates and seroconversion rates were determined on day 21. Geometric mean titers, seroprotection and seroconversion rates were similar between the intradermal and intramuscular vaccines in both age groups for all three vaccine strains (A/H1N1, A/H3N2 and B). Both vaccines met Committee for Medicinal Products for Human Use criteria for all three strains. Solicited systemic reactions of the intradermal groups were generally mild, transient, and similar to those of the intramuscular groups. Solicited injection site reactions were more frequent in the intradermal groups but were mostly mild, transient, and consisted mainly of pain, erythema, and pruritus. No treatment-related serious adverse events or other safety concerns were reported. These results confirm that Intanza/IDflu is an effective and well-tolerated alternative to IM influenza vaccination. (Clinicaltrials.gov NCT ID: NCT01215669).

Acceptance and opinions of Intanza/IDflu intradermal influenza vaccine in the Czech Republic and Turkey.

INTRODUCTION: Intanza(®)/IDflu(®) (Sanofi Pasteur SA, Lyon, France), a split-virion, trivalent influenza vaccine delivered by intradermal injection with a microinjection system, became available in adults 18-59 years of age (9 µg) and ≥60 years of age (15 µg) as of the 2010/2011 northern hemisphere influenza season. METHODS: This study assessed the acceptability of intradermal vaccination with Intanza/IDflu in routine clinical practice in adult vaccinees and their vaccine prescribers. Vaccine prescribers and adults who had elected to be vaccinated with Intanza/IDflu during the 2010/2011 northern hemisphere influenza season were recruited to complete surveys about their opinions of influenza vaccination and their acceptance of the intradermal vaccination. Czech subjects 18-59 years of age were vaccinated with the 9 µg formulation and those ≥60 years of age with the 15 µg formulation of Intanza/IDflu. All Turkish subjects were vaccinated with the 9 µg formulation, as Intanza/IDflu 15 µg was not available in Turkey at the time the survey was conducted. RESULTS: One thousand and twelve vaccinees and 28 vaccine prescribers in the Czech Republic, and 249 vaccinees and 15 vaccine prescribers in Turkey completed questionnaires. Overall, 96.1% of vaccinees were satisfied or very satisfied with Intanza/IDflu. The main reason for satisfaction was that the injection was considered minimally painful. Most (93.9%) vaccinees reported that they would prefer to receive the same vaccination next year. Furthermore, 95.3% of vaccine prescribers were satisfied or very satisfied with the intradermal vaccine, and 82.6% preferred intradermal over intramuscular vaccination. CONCLUSIONS: Intradermal vaccination for seasonal influenza using Intanza/IDflu is well accepted by adult vaccinees and vaccine prescribers. By providing an additional, well-accepted method, Intanza/IDflu might help increase seasonal influenza vaccination rates in adults.

Acceptance of Intanza® 9 µg intradermal influenza vaccine in routine clinical practice in Australia and Argentina.

INTRODUCTION: Intanza® 9 µg (Sanofi Pasteur SA, Lyon, France), a split virion trivalent influenza vaccine delivered by intradermal injection with a microinjection system, became available as a vaccination for adults aged 18 to 59 years old, as of the 2010 southern hemisphere influenza season. METHODS: This study was designed to assess the acceptability of intradermal vaccination with Intanza 9 µg in routine clinical practice by adult vaccinees and their prescribers. Prescribers and healthy adults 18 to 59 years old in Australia and Argentina who had elected to be vaccinated with Intanza 9 µg during the 2010 southern hemisphere influenza season were recruited to complete surveys about their opinions of influenza vaccination and acceptance of the intradermal vaccination. RESULTS: 1402 vaccinees and 30 prescribers in Australia, and 264 vaccinees and 16 prescribers in Argentina responded to surveys. In both countries, 98% of vaccinees were satisfied or very satisfied with Intanza 9 µg. The main reasons for satisfaction were that the injection was considered minimally painful and that the vaccination was quickly administered. Most (95%) vaccinees reported that they would prefer to receive the same vaccination next year. Furthermore, 85% of prescribers were satisfied or very satisfied with the intradermal vaccine. CONCLUSION: Intradermal vaccination for seasonal influenza using Intanza 9 µg is well accepted both by adult vaccinees and prescribers. By providing an additional, well-accepted method, Intanza 9 µg might help increase seasonal influenza vaccination rates in adults.

Immunogenicity and safety of intradermal influenza vaccination in renal transplant patients who were non-responders to conventional influenza vaccination.

Seasonal influenza epidemics are associated with high morbidity and mortality particularly in high-risk patients. Conventionally administered influenza vaccines show reduced efficacy in populations with weakened immune systems such as solid-organ transplant patients. This study assesses the safety and immunogenicity of an intradermally administered influenza vaccine in renal transplant patients previously identified as non-responders to a licensed trivalent inactivated influenza vaccine (TIV). Renal transplant patients with low or no hemagglutination inhibiting (HI) antibody response to an A influenza (H3N2) vaccine strain were enrolled in a descriptive phase II, open-label, randomized, multicentre trial: 31 received an investigational intradermal TIV, and 31 received a conventionally administered TIV. Both vaccines contained 15 µg hemagglutinin (HA) per strain. The 62 study subjects were selected from 201 renal transplant patients aged 18-60 years who had been vaccinated in the previous year with a conventionally administered TIV. Vaccination was safe and well tolerated by each administration route. The immunogenicity results of this descriptive study showed ID TIV vaccination to induce HI antibody responses that trended higher in renal transplant patients than conventionally administered TIV. Our results suggest that ID influenza vaccination may offer enhanced immunogenicity and protection in persons who do not respond well to conventional TIV. Further studies should be conducted in immunocompromised populations to validate the trends for higher efficacy of ID vs. conventional route of immunization against influenza.

Intradermal influenza vaccine for older adults: a randomized controlled multicenter phase III study.

In a 3-year, randomized, controlled, open-label phase III trial enrolling 3707 adults aged > or = 60 years we evaluated whether the immunogenicity of an intradermal trivalent inactivated seasonal influenza vaccine, containing 15 microg of haemagglutinin per strain per 0.1 ml dose, is superior to that of a conventional intramuscular vaccine. Intradermal vaccine was given using an intradermal microinjection system. After the first vaccination, both vaccines satisfied the immunogenicity criteria for influenza vaccines for older adults set out in European regulatory guidelines, and geometric mean haemagglutination inhibition antibody titers and seroprotection rates were higher (statistically superior) with intradermal vaccination. Higher immune responses with intradermal vaccine were also observed after the 2nd and 3rd annual vaccinations. Both vaccines were well tolerated with similar systemic reactogenicity profiles. This intradermal influenza vaccine for older adults is a beneficial option for influenza protection, consistently enhancing antibody responses without compromising safety.

Seasonal influenza vaccine delivered by intradermal microinjection: A randomised controlled safety and immunogenicity trial in adults.

Influenza vaccines remain largely underused. A promising alternative to current intramuscular vaccines is a trivalent inactivated influenza vaccine (TIV) delivered using a microinjection system to offer a less invasive and possibly more acceptable vaccination. A phase II, multicentre, randomised open-label study in 978 healthy adults (18-57 years) evaluated the immunogenicity and safety of intradermal TIV. Subjects received a 0.1 ml injection of intradermal TIV, containing 9 microg of haemagglutinin (HA) per strain (n = 588) or a conventional 0.5 ml intramuscular vaccine (15 microg of HA/strain; n = 390). Intradermal TIV induced non-inferior humoral immune responses against all three strains and superior responses against both A strains (H1N1, H3N2) compared with the control. Both vaccines were well tolerated.

Intradermal influenza vaccine administered using a new microinjection system produces superior immunogenicity in elderly adults: a randomized controlled trial.

BACKGROUND: Enhanced influenza vaccines are needed to provide improved protection for elderly individuals. The intradermal vaccination route was hypothesized to provide immunogenicity superior to that provided by the intramuscular vaccination route. METHODS: In a multicenter, randomized study, 1107 volunteers >60 years of age received intradermal trivalent inactivated influenza vaccine containing 15 or 21 microg of hemagglutinin per strain or intramuscular control vaccine. Intradermal vaccines used a novel microinjection system designed to ensure easy, convenient, consistent vaccination. The primary end points of the study were the strain-specific hemagglutination inhibition geometric mean titers (GMTs) noted 21 days after vaccination. Groups were compared using noninferiority and superiority analyses. RESULTS: For each strain, the GMTs noted in association with each intradermal vaccine were superior to those noted with the intramuscular control (adjusted P< .0001). Seroprotection rates, seroconversion rates, and mean titer increases were also superior for intradermally administered vaccine in all but one of the analyses undertaken. Systemic reactogenicity was comparable between routes. Local injection site reactions, particularly erythema but not pain, were more commonly associated with intradermal vaccination. CONCLUSIONS: For the first time, the intradermal vaccination route has been used to elicit immune responses significantly superior to those noted in association with the conventional intramuscular vaccination route. This was done using an easy-to-use, reliable microinjection system. This superior response is expected to enhance annual protection against influenza in this vulnerable population. TRIAL REGISTRATION: Clinicaltrials.gov registry number: NCT00296829.

Immunogenicity of an inactivated hepatitis A pediatric vaccine: three-year post-booster follow-up.

The persistence of anti-hepatitis A virus antibody concentrations was followed over 3 years in 177 healthy children following primary and booster vaccination with an inactivated hepatitis A vaccine, Avaxim 80 pediatric. Seroconversion rates (post-immunization anti-HAV antibody concentration >or=20 mIU/mL) and geometric mean concentrations (GMC) were estimated for each of three age groups: 18 month--3 years, 4--8 years, and 9--15 years. Only subjects who were initially HAV-seronegative at inclusion (<20 mIU/mL) were analyzed. Follow-up visits at years 1, 2, and 3 involved 177, 149, and 135 children, respectively. A decline in GMCs of about 74% occurred during the first year, from 3,060 to 814 mIU/mL overall, but did not continue during years 2 and 3. All subjects remained seropositive (antibody concentration >or=20 mIU/mL), with overall GMCs of 814, 891, and 924 mIU/mL in years 1--3, respectively. The inactivated hepatitis A study-vaccine resulted in sustained seroprotective antibody concentrations in 100% of these children, without a significant decline in antibiotic concentrations over the 3 years following booster injection, thus demonstrating the long-term protection expected with this vaccine.

A combined dual-chamber typhoid/hepatitis A vaccine as a booster dose in hepatitis A primed adults.

Vivaxim is a combined hepatitis A/typhoid fever vaccine (HA/Vi) licensed for vaccination of travellers, but long-term protection against hepatitis A requires two immunisations at least 6 months apart. A randomised, controlled study was performed in 116 healthy adults primed with hepatitis A vaccine (Avaxim) to compare immune responses to HA/Vi and Avaxim given as booster doses 6 months later. Both vaccines elicited marked booster responses achieving antibody geometric mean titres (GMTs) of 4576 and 3760 mIU/ml in the HA/Vi and Avaxim groups, respectively. Although twice as frequent in the HA/Vi group, local reactions (mostly pain) were mainly mild and transient, probably reflecting the larger volume injected (1ml). Vivaxim offers a convenient means of administering both HA and typhoid fever vaccines in subjects already primed for hepatitis A.

Immunogenicity and safety of two doses of a paediatric hepatitis A vaccine in thai children: comparison of three vaccination schedules.

As fewer children in Thailand are exposed to hepatitis A virus (HAV) and so do not have seroprotective anti-HAV antibodies, they are becoming an important source of HAV transmission. A flexible HAV vaccination schedule would facilitate incorporation of the vaccine into existing immunization programmes, and we compared the immunogenicity and safety of three HAV immunization schedules. An open, randomized, clinical trial was carried out in which healthy children were given a primary dose of the inactivated hepatitis A vaccine, Avaxim 80 paediatric, with a booster dose 6, 12 or 18 months later. Anti-HAV geometric mean concentrations (GMC), seroconversion rates, and GMC ratios (GMCR) of the three schedules were compared and reactogenicity was evaluated. Seroconversion rates were above 98 per cent (per group) up to the booster. The three schedules were equivalent in terms of GMCRs, each eliciting a large booster effect. Local reactions were reported for fewer than 9 per cent of each group after dose one and less frequently after the booster dose. Injection site pain, gastrointestinal tract disorders and fever were the most commonly reported adverse events. No vaccine-related serious adverse events were reported. It was concluded that the hepatitis A vaccine, Avaxim 80 paediatric, is safe and immunogenic when given as a two-dose schedule to healthy seronegative children aged 5-10 years, with the second dose given at either 6, 12 or 18 months after the first.

Comparison of two combined vaccines against typhoid fever and hepatitis A in healthy adults.

A prospective, randomised, observer-blind, comparative study was performed in healthy adults with a new hepatitis A/typhoid combined vaccine, Viatim, and the marketed Hepatyrix vaccine. Both vaccines induced high levels of protective antibodies, but typhoid responses were higher and hepatitis A responses more rapid with Viatim compared with Hepatyrix. Both vaccines were well tolerated, no serious adverse events (SAEs) occurred, but more Viatim vaccinees had more mild or moderate local reactions (82.7%) than Hepatyrix (53.1%, p < 0.001). In this direct comparison Viatim induced more local reactions, but elicited a more rapid and higher immune response to both antigens than Hepatyrix.