How soon after a prior tetanus-diphtheria vaccination can one give adult formulation tetanus-diphtheria-acellular pertussis vaccine?

Overuse of tetanus toxoid vaccine: a common but under-addressed issue in Nepal

Introduction and importance

Tetanus, though potentially fatal, is preventable with proper vaccination, but high tetanus titers from frequent or higher doses can lead to increased adverse events. In countries like Nepal, where tetanus vaccines are readily available over the counter, irrational and frequent dosing, especially in certain occupational groups, is a noted issue.

Case presentation

A 28-year-old metal worker presented with a superficial cut on his forearm, managed with standard wound care, and reported a history of frequent tetanus vaccinations. Given his extensive vaccination history, a tetanus toxoid injection was deemed unnecessary, and he was educated on proper vaccination schedules and advised to seek medical attention for future injuries.

Clinical discussion

Timely administration of vaccines for pre-exposure and postexposure prophylaxis is crucial for combating tetanus, with booster doses recommended every 10 years or as needed for wound management. High antibody titers from frequent tetanus vaccinations can increase the risk of adverse events, prompting guidelines to avoid administering Td more frequently than every 10 years unless necessary. Local reactions, like pain and swelling at the injection site, are common, while systemic reactions can include fever and peripheral neuropathy. Over-immunization is a concern in some regions, with frequent unnecessary booster doses potentially causing harm and highlighting the need for adherence to vaccination guidelines.

Conclusion

Modifying and monitoring adult Td booster vaccination can lead to significant cost savings and fewer adverse events, requiring proper vaccination record-keeping, accurate assessment, and adherence to guidelines by healthcare workers.

Immunogenicity at delivery after Tdap vaccination in successive pregnancies

Background

Tetanus, diphtheria, acellular pertussis (Tdap) vaccination is recommended to be administered in every pregnancy. Although the safety of this strategy has been confirmed, the immunogenicity of Tdap vaccination in two successive pregnancies has not yet been described. This study investigated Tdap-specific immunity levels and transplacental transfer in two successive pregnancies after repeated Tdap-vaccination.

Methods

Women enrolled in prior studies on Tdap vaccination during pregnancy were invited to participate in a follow-up study if they became pregnant again. Women who received a Tdap vaccine in both pregnancies were considered for this analysis. Tdap-specific total IgG and IgG subclasses were measured with a multiplex immunoassay.

Results

In total, 27 participants with a mean interval between deliveries of 2.4 years were included in the analysis. In maternal serum, Tdap-specific total IgG levels were comparable at both deliveries whereas in cord serum, all Tdap-specific total IgG antibody levels were reduced at the second compared to the first delivery. This was largely reflected in the IgG1 levels in maternal and cord serum. Transplacental transfer ratios of total IgG and IgG1 were also mostly reduced in the second compared to the first pregnancy.

Conclusion

This study reports for the first time Tdap-specific total IgG and IgG subclass levels and transfer ratios after repeated Tdap vaccination in successive pregnancies. We found reduced transfer of most Tdap-specific IgG and IgG1 antibodies in the successive pregnancy. As pertussis-specific antibodies wane quickly, Tdap vaccination in each pregnancy remains beneficial. However, more research is needed to understand the impact of closely spaced booster doses during pregnancy on early infant protection against pertussis.

Arthus Reaction as an Adverse Event Following Tdap Vaccination

Repeat administration of tetanus toxoid-containing vaccines has rarely been associated with Arthus phenomenon, an immune-complex reaction. In the US, since 2013, tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccines (Tdap) have been recommended for administration during each pregnancy. Separately, in 2019, one Tdap was approved for repeat administration in adults in the US. We aimed to describe trends in spontaneously reported Arthus reactions following Tdap in the US and to assess the risk of this phenomenon in persons receiving Tdap repeatedly. We reviewed Arthus reports in the Vaccine Adverse Events Reporting System (VAERS), 1990-2018. Reporting rates were estimated using Tdap doses distributed data. A systematic literature review was conducted in MEDLINE for any Arthus cases reported in Tdap clinical trials and observational studies published between 2000 and 2019. We found 192 Arthus reports in VAERS after any vaccine, of which 36 occurred after Tdap and none were reported during pregnancy. The Arthus reporting rate was estimated at 0.1 per million doses distributed. We identified eight published studies of Tdap administration within five years after a previous dose of tetanus toxoid-containing vaccine; no Arthus cases were reported. We conclude that Arthus reaction following Tdap is extremely rare. Increasing frequency of repeat Tdap administration in adults in the US did not result in a detectable increase in reporting rates of this phenomenon, confirming the favorable safety profile of Tdap.

Is there any harm in administering extra-doses of vaccine to a person? Excess doses of vaccine reported to the Vaccine Adverse Event Reporting System (VAERS), 2007-2017

BACKGROUND

The administration of an extra dose of a vaccine may occur due to a programmatic error (e.g., vaccination error) when there is need to provide one of the antigens of a combination vaccine not readily available as a single antigen, or when there is need to provide immunization in a person with uncertain vaccination histories (e.g., refugees). There is little data available on the safety of an extra dose of vaccine.

OBJECTIVE

To assess for the presence of adverse events (AEs) most commonly reported following the administration of excess doses of vaccine in the Vaccine Adverse Event Reporting System (VAERS).

METHODS

We searched VAERS for US reports where an excess dose of vaccine was administered to a person received from 1/1/2007 through 1/26/2018. We reviewed medical records for all serious reports and a random sample of non-serious reports. The most common AEs among reports of excess dose of vaccine administered were compared with the corresponding AEs for all vaccines reported to VAERS during the same period.

RESULTS

Out of 366,815 total VAERS reports received, 5067 (1.4%) reported an excess dose of vaccine was administered; 3898 (76.9%) did not describe an adverse health event (AHE). The most common vaccines reported were trivalent inactivated influenza (15.4%), varicella (13.9%), hepatitis A (11.4%), and measles, mumps, rubella, varicella (11.1%). Among reports where only AHEs were reported, the most common were pyrexia (12.8%), injection site erythema (9.7%), injection site pain (8.9%), and headache (6.6%). The percentage of AHEs among these reports was comparable to all reports submitted to VAERS during the same study period.

CONCLUSION

More than three-fourths of reports of an excess dose of vaccine did not describe an AHE. Among reports where an AHE event was reported, we did not observe any unexpected conditions or clustering of AEs.

Randomized Controlled Trial of the Safety and Immunogenicity of Revaccination With Tetanus-Diphtheria-Acellular Pertussis Vaccine (Tdap) in Adults 10 Years After a Previous Dose

BACKGROUND

Reduced-antigen-content tetanus, diphtheria, and acellular pertussis (Tdap) vaccine is recommended in many countries for boosting immunity in adolescents and adults. Although immunity to these antigens wanes with time, currently available Tdap products are not labeled for repeat administration in the United States.

METHODS

We performed an observer-blinded, randomized controlled trial in 1330 adults aged 18 to <65 years who received either the Tdap (n = 1002) or tetanus-diphtheria (Td) (n = 328) vaccine 8 to 12 years after a dose of Tdap vaccine administered previously. Solicited adverse events following immunization were documented for 7 days after vaccination, and serious adverse events and adverse events of medical significance were documented for 6 months after vaccination. Levels of antibodies against component vaccine antigens were measured before and 1 month after vaccination.

RESULTS

A solicited adverse event was reported by 87.7% of Tdap and 88.0% of Td vaccine recipients. We found no significant differences in the rates of injection-site reactions, systemic reactions, or serious adverse events between the vaccine groups. A robust antibody response to each pertussis antigen in the Tdap-vaccinated group was found; postvaccination-to-prevaccination geometric mean antibody concentration ratios were 8:1 (pertussis toxoid), 5.9 (filamentous hemagglutinin), 6.4 (pertactin), and 5.2 (fimbriae 2 and 3). Postvaccination geometric mean concentrations of tetanus antibody (4.20 and 4.74 IU/mL, respectively) and diphtheria antibody (10.1 and 12.6 IU/mL, respectively) were similar in the Tdap and Td groups, and the rates of seroprotection against tetanus and diphtheria were >99% in both groups.

CONCLUSIONS

A second dose of Tdap vaccine in adults approximately 10 years after a previous dose was well tolerated and immunogenic. These data might facilitate consideration of providing Tdap booster doses to adults.

Emerging Topics in Vaccine Therapeutics for Adolescents and Adults: An Update for Immunizing Pharmacists

Vaccine therapeutics and the practice of immunization provision are ever-changing. As pharmacy-based immunization services continue to flourish in the United States, more and more patients are requesting both routine and travel vaccines in community pharmacies. However, vaccine recommendations from the Centers for Disease Control and Prevention/Advisory Committee on Immunization Practices (CDC/ACIP) can sometimes differ from product-specific US Food and Drug Administration (FDA)-indicated uses. In addition, changes in vaccine schedules, product availability, and disease outbreaks can present immunizing pharmacists with scenarios requiring a high level of clinical judgment. Thus, it is of paramount importance that all immunizing pharmacists maintain competency in the most recent evidence in vaccine therapeutics, as well as practice standards for vaccine provision and administration. This review provides an update of the most recent literature surrounding emerging topics in adolescent and adult immunizations—highlighting influential studies and recent developments in the prevention of herpes zoster, human papillomavirus (HPV), measles, mumps, rubella (MMR), meningococcal disease, tetanus, diphtheria, and pertussis. Key concepts discussed include the emergence of the new recombinant zoster vaccine (RZV), meningococcal vaccine product selection, MMR revaccination during disease outbreaks, tetanus vaccine product selection, and duration of pertussis immunity with vaccination.

Active surveillance of 2017 seasonal influenza vaccine safety: an observational cohort study of individuals aged 6 months and older in Australia

OBJECTIVE

To actively solicit adverse events experienced in the days following immunisation with quadrivalent inactivated influenza vaccine using Australia's near real-time, participant-based vaccine safety surveillance system, AusVaxSafety.

DESIGN AND SETTING

Observational cohort study conducted in 194 sentinel surveillance immunisation sites (primary care, hospital and community-based clinics) across Australia.

PARTICIPANTS

Individuals aged ≥6 months who received a routine seasonal influenza vaccine at a participating site (n=102 911) and responded to a survey (via short message service or email) sent 3 days after vaccination about adverse events experienced (n=73 892; 71.8%).

MAIN OUTCOME MEASURE

Near real-time and cumulative participant-reported rates of any adverse event, fever or medical attendance experienced within 3 days after vaccination overall, by brand, age, pregnancy status and concomitant vaccine receipt.

RESULTS

Participant median age was 57 years (range: 6 months to 102 years); 58.1% (n=42 869) were female and 2.7% (n=2018) were pregnant. Near real-time fast initial response cumulative summation and Bayesian analyses of weekly event rates did not demonstrate a safety signal. Children aged 6 months to 4 years had higher event rates (522/6180; 8.4%) compared with older ages; participants aged ≥65 years reported fewer events (1695/28 154; 6.0%). There were no clinically significant differences in safety between brands, by age group or overall. Cumulative data analysis demonstrated that concomitant vaccination was associated with increased rates of fever (2.1% vs 0.8%) and medical attendance (0.8% vs 0.4%), although all rates were low and did not exceed expected levels.

CONCLUSIONS

Novel, postmarketing AusVaxSafety surveillance demonstrated comparable and expected safety outcomes for the 2017 quadrivalent inactivated influenza vaccine brands used in Australia. These near real-time, participant-reported data are expected to encourage confidence in vaccine safety and promote uptake.

Reactogenicity and immunogenicity of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap) in pregnant and nonpregnant women

OBJECTIVE

Tetanus toxoid, reduced diphtheria toxoid, and acellular pertusiss (Tdap) vaccine is recommended during each pregnancy, regardless of prior receipt. Data on reactogenicity and immunogenicity, particularly after repeated Tdap, are limited. We compared local injection-site and systemic reactions and serologic response following Tdap in (1) pregnant and nonpregnant women and (2) pregnant women by self-reported prior Tdap receipt.

STUDY DESIGN

Pregnant women (gestational age 20-34 weeks) and nonpregnant women receiving Tdap were enrolled in this observational study. Injection-site and systemic reactions were assessed for one week post-vaccination. Pertussis toxin, filamentous hemagglutinin, pertactin, fimbriae, tetanus and diphtheria specific IgG antibody titers were determined by standardized enzyme-linked immunosorbent assay at baseline and 28 days post-vaccination. Reactogenicity and serologic responses were compared by pregnancy status, and within pregnant women by self-reported prior Tdap receipt.

RESULTS

374 pregnant and 225 nonpregnant women were vaccinated. Severe local or systemic reactions or "any" fever were uncommon (≤3% for both groups). Moderate/severe injection-site pain was significantly higher in pregnant (17.9%) versus nonpregnant (11.1%) women, but did not prompt a healthcare visit. Proportions of other moderate/severe or any severe reactions were not significantly higher in pregnant compared to nonpregnant women. Moderate/severe (including pain) and severe reactions were not significantly higher in pregnant women receiving repeat versus first-time Tdap. Antibody titers increased from baseline to post-vaccination for all vaccine antigens in pregnant and nonpregnant women; post-vaccination titers against pertussis toxin and filamentous hemagglutinin were significantly higher in nonpregnant versus pregnant women (p < 0.01).

CONCLUSION

Tdap was well-tolerated in pregnant and nonpregnant women. Pregnant women were more likely to report moderate/severe pain at the Tdap injection-site compared with nonpregnant women, but did not necessitate medical visits. Prior Tdap receipt did not increase occurrence of moderate/severe local or systemic reactions in pregnant women. Serologic responses to all vaccine antigens were robust. Clinical Trial Registration@ClinicalTrials.gov. NCT02209623. https://clinicaltrials.gov/ct2/show/NCT02209623.

Prevention of Pertussis, Tetanus, and Diphtheria with Vaccines in the United States: Recommendations of the Advisory Committee on Immunization Practices (ACIP)

This report compiles and summarizes all recommendations from CDC's Advisory Committee on Immunization Practices (ACIP) regarding prevention and control of tetanus, diphtheria, and pertussis in the United States. As a comprehensive summary of previously published recommendations, this report does not contain any new recommendations and replaces all previously published reports and policy notes; it is intended for use by clinicians and public health providers as a resource. ACIP recommends routine vaccination for tetanus, diphtheria, and pertussis. Infants and young children are recommended to receive a 5-dose series of diphtheria and tetanus toxoids and acellular pertussis (DTaP) vaccines, with one adolescent booster dose of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine. Adults who have never received Tdap also are recommended to receive a booster dose of Tdap. Women are recommended to receive a dose of Tdap during each pregnancy, which should be administered from 27 through 36 weeks' gestation, regardless of previous receipt of Tdap. After receipt of Tdap, adolescents and adults are recommended to receive a booster tetanus and diphtheria toxoids (Td) vaccine every 10 years to assure ongoing protection against tetanus and diphtheria.

Controlling pertussis: how can we do it? A focus on immunization

INTRODUCTION

Pertussis is a highly contagious disease of the respiratory tract which is caused by the bacterium Bordetella pertussis and is most severe in those <1 year of age. A vaccine against pertussis, introduced in the 1950's, led to a significant decrease in incidence of the disease, but recent increases in outbreaks have been attributed to insufficient vaccine uptake, suboptimal protection conferred by vaccines, and waning immunity after immunization. Areas covered: In this review we discuss the major challenges for controlling pertussis, and what we believe the best strategies are to overcome these challenges, focusing on immunization against pertussis in Europe, but with recommendations that are relevant worldwide. Expert commentary: To provide maximum vaccine coverage we propose a schedule that incorporates immunization of infants, preschoolers, adolescents, adults, and pregnant women. Uptake of vaccines may also vary between populations due to a variety of causes, including hesitancy to vaccinate, so any national strategy to control pertussis should also include sustaining public and healthcare provider confidence in vaccination. Addressing and improving regional variations in surveillance will also help better monitor annual incidence and outbreaks. Looking towards the future, the development of new pertussis vaccines with longer duration of protection would be advantageous.

Tetanus-diphtheria-acellular pertussis vaccination for adults: an update

Although tetanus and diphtheria have become rare in developed countries, pertussis is still endemic in some developed countries. These are vaccine-preventable diseases and vaccination for adults is important to prevent the outbreak of disease. Strategies for tetanus, diphtheria, and pertussis vaccines vary from country to country. Each country needs to monitor consistently epidemiology of the diseases and changes vaccination policies accordingly. Recent studies showed that tetanus–diphtheria–acellular pertussis vaccine for adults is effective and safe to prevent pertussis disease in infants. However, vaccine coverage still remains low than expected and seroprevalence of protective antibodies levels for tetanus, diphtheria, and pertussis decline with aging. The importance of tetanus–diphtheria–acellular pertussis vaccine administration should be emphasized for the protection of young adult and elderly people also, not limited to children.

Performance of a bedside test for tetanus immunity: results of a cross-sectional study among three EDs in the Netherlands in 2012-2013

INTRODUCTION

Despite sustained high vaccination coverage and a national guideline by the Health Council (HC-guideline) on tetanus postexposure prophylaxis (T-PEP), tetanus sporadically occurs in the Netherlands. This study aims to assess the added value of a bedside test for tetanus immunity (Tetanos Quick Stick (TQS); Ingen BioSciences Group, France), in the context of routine T-PEP in two adult cohorts: those born before introduction of tetanus toxoid vaccination in the National Immunization Programme (NIP) in 1957 (pre-NIP-cohort; n=196) and those born after (NIP-cohort; n=405).

METHODS

Adults included at the time of visiting one of three participating EDs received T-PEP as per routine recommendations. Subsequently, a nurse performed the TQS and filled in a questionnaire. We compared the indication for T-PEP based on TQS results with those based on the HC-guideline and with actually administration of T-PEP, stratified by cohort.

RESULTS

Among the pre-NIP and NIP-cohort, 16% and 9%, respectively, received T-PEP, while this was not indicated based on the HC-guideline. Furthermore, 8% and 7%, respectively, did not get T-PEP, although it was indicated by the guideline. Comparing the indication derived from the HC-guideline with TQS result found that 22% (pre-NIP-cohort) and 8% (NIP-cohort) were not eligible for T-PEP according to the HC-guideline but had a negative TQS. Conversely, 36% (pre-NIP-cohort) and 73% (NIP-cohort) were eligible for T-PEP according to the HC-guideline but had positive TQS, indicating sufficient tetanus protection.

CONCLUSION

Use of the TQS would allow better targeting of T-PEP. Furthermore, stricter adherence to the HC-guideline can prevent overimmunisation and decrease the risk of tetanus.

Association of Tdap Vaccination With Acute Events and Adverse Birth Outcomes Among Pregnant Women With Prior Tetanus-Containing Immunizations

IMPORTANCE

The Advisory Committee on Immunization Practices (ACIP) recommends the tetanus, diphtheria, and acellular pertussis (Tdap) vaccine for pregnant women during each pregnancy, regardless of prior immunization status. However, safety data on repeated Tdap vaccination in pregnancy is lacking.

OBJECTIVE

To determine whether receipt of Tdap vaccine during pregnancy administered in close intervals from prior tetanus-containing vaccinations is associated with acute adverse events in mothers and adverse birth outcomes in neonates.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study in 29,155 pregnant women aged 14 through 49 years from January 1, 2007, through November 15, 2013, using data from 7 Vaccine Safety Datalink sites in California, Colorado, Minnesota, Oregon, Washington, and Wisconsin.

EXPOSURES

Women who received Tdap in pregnancy following a prior tetanus-containing vaccine less than 2 years before, 2 to 5 years before, and more than 5 years before.

MAIN OUTCOMES AND MEASURES

Acute adverse events (fever, allergy, and local reactions) and adverse birth outcomes (small for gestational age, preterm delivery, and low birth weight) were evaluated. Women who were vaccinated with Tdap in pregnancy and had a prior tetanus-containing vaccine more than 5 years before served as controls.

RESULTS

There were no statistically significant differences in rates of medically attended acute adverse events or adverse birth outcomes related to timing since prior tetanus-containing vaccination. [table: see text].

CONCLUSIONS AND RELEVANCE

Among women who received Tdap vaccination during pregnancy, there was no increased risk of acute adverse events or adverse birth outcomes for those who had been previously vaccinated less than 2 years before or 2 to 5 years before compared with those who had been vaccinated more than 5 years before. These findings suggest that relatively recent receipt of a prior tetanus-containing vaccination does not increase risk after Tdap vaccination in pregnancy.

Vaccination in elite athletes

Public health vaccination guidelines cannot be easily transferred to elite athletes. An enhanced benefit from preventing even mild diseases is obvious but stronger interference from otherwise minor side effects has to be considered as well. Thus, special vaccination guidelines for adult elite athletes are required. In most of them, protection should be strived for against tetanus, diphtheria, pertussis, influenza, hepatitis A, hepatitis B, measles, mumps and varicella. When living or traveling to endemic areas, the athletes should be immune against tick-borne encephalitis, yellow fever, Japanese encephalitis, poliomyelitis, typhoid fever, and meningococcal disease. Vaccination against pneumococci and Haemophilus influenzae type b is only relevant in athletes with certain underlying disorders. Rubella and papillomavirus vaccination might be considered after an individual risk–benefit analysis. Other vaccinations such as cholera, rabies, herpes zoster, and Bacille Calmette–Guérin (BCG) cannot be universally recommended for athletes at present. Only for a very few diseases, a determination of antibody titers is reasonable to avoid unnecessary vaccinations or to control efficacy of an individual’s vaccination (especially for measles, mumps, rubella, varicella, hepatitis B and, partly, hepatitis A). Vaccinations should be scheduled in a way that possible side effects are least likely to occur in periods of competition. Typically, vaccinations are well tolerated by elite athletes, and resulting antibody titers are not different from the general population. Side effects might be reduced by an optimal selection of vaccines and an appropriate technique of administration. Very few discipline-specific considerations apply to an athlete’s vaccination schedule mainly from the competition and training pattern as well as from the typical geographical distribution of competitive sites.

Shortened interval between tetanus vaccines

OBJECTIVE

To identify the minimum safe interval between tetanus-diphtheria (Td) and tetanus-diphtheria-acellular pertussis (Tdap) vaccines.

DATA SOURCES

Literature was retrieved through a review of ImmunoFacts, the Centers for Disease Control and Prevention (CDC) Web site, MEDLINE (1966-February 2012) and International Pharmaceutical Abstracts (1970-February 2012) using the terms Tdap, Td, and interval. In addition, reference citations from publications identified were reviewed.

STUDY SELECTION AND DATA EXTRACTION

All English-language articles identified from the data sources were evaluated. Studies addressing an interval of 2 years or less between Td and Tdap vaccines were included.

DATA SYNTHESIS

Two observational noninferiority studies have evaluated the safety of an interval of 2 years or less. The first involved a school-based immunization program to compare the safety of a single dose of Tdap given 18 months to 9 years after a tetanus and diphtheria toxoid-containing vaccine versus an interval of 10 or more years. Injection site erythema and swelling were increased among participants with shortened intervals between vaccines; however, no serious adverse events, entire limb swelling, or Arthus-like reactions were reported. The second study involved health care workers who received Tdap during a pertussis outbreak with the objective to compare safety of intervals less than 2 years between prior tetanus vaccination and Tdap with intervals 2 years or more. Criteria for noninferiority were met overall between the 2 intervals in terms of moderate and severe injection site reactions. Fever was more common with the shortened interval, as was any redness or any swelling. No serious adverse events were reported among the group with an interval of less than 2 years between vaccine administration.

CONCLUSIONS

Although well-designed randomized controlled trials are lacking, the current observational evidence and CDC provisional recommendations support a shortened interval between Td and Tdap vaccines to protect health care workers from pertussis. Intervals less than 2 years may be associated with an increased incidence of local injection site reactions.

Immune responses in adults to revaccination with a tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine 10 years after a previous dose

BACKGROUND

Although decennial adult boosters of tetanus and diphtheria toxoids are recommended in Canada and the United States, a second dose of pertussis vaccine during adulthood is not currently recommended.

METHODS

This open-label, multicenter study compared the safety and immunogenicity of a first dose of an adult formulation of tetanus, diphtheria, and acelluar pertussis vaccine (Tdap) with a repeat dose of Tdap in adults who had received Tdap 10 years previously.

RESULTS

A total of 769 participants ranging in age from 20 to 72 years took part in this study; 92.3% of naïve and 92.7% of repeat-dose participants had at least one solicited adverse event. Injection-site pain (84.4% and 87.8%), erythema (29.7% and 23.1%), and swelling (23.3% and 20.5%), and myalgia (53.5% and 60.1%), headache (37.6% and 40.6%), malaise (29.0% and 29.4%), and fever (4.9% and 4.2%) were the most common solicited adverse events reported in the naïve and repeat-dose groups, respectively. Postvaccination antibody levels ≥0.1 IU/mL were achieved by 99.7% of the naïve-group participants and all of the repeat-dose participants for tetanus and 96.1% of the naïve group and 98.5% of the repeat-dose group for diphtheria, both meeting the predefined noninferiority criteria. For pertussis antibodies, anti-PT (89.2 EU/mL vs. 116 EU/mL) was higher in the repeat-dose group, anti-FHA (249 vs. 214) and anti-PRN (216 vs. 266) were similar, and anti-FIM (1015 vs. 779) was higher in the naïve group. Noninferiority criteria were met for all antigens except for anti-FIM.

CONCLUSION

A repeat dose of Tdap vaccine 10 years after the first dose was well tolerated and immunogenic in adults (ClinicalTrials.gov identifier: NCT00712959).

Vaccination recommendations for Germany

BACKGROUND

Vaccination is an effective means of preventing infectious diseases. In Germany, the Standing Vaccination Committee at the Robert Koch Institute (Ständige Impfkommission, STIKO) issues recommendations on vaccination to prevent the occurrence and spread of infectious diseases in the nation's population.

METHODS

Selective literature review, including consideration of the current STIKO recommendations.

RESULTS

The annually updated vaccination calendar currently includes recommendations for vaccination against diphtheria, tetanus, pertussis, type b Haemophilus influenzae, hepatitis B, poliomyelitis, and pneumococci, beginning at the age of eight weeks. From the age of twelve months onward, children should be vaccinated against measles, mumps, rubella, varicella, and serogroup C meningococci. In later childhood and adolescence, booster vaccinations are recommended, in addition to the provision of any vaccinations that may have been missed. Girls aged 12 to 17 years should be vaccinated against human papilloma virus. Adults should have their tetanus and diphtheria vaccinations refreshed regularly, and their pertussis vaccination refreshed once; from age 60 onward, they should be vaccinated against pneumococci and influenza.

CONCLUSIONS

The vaccinations recommended by the STIKO are available to all German citizens free of charge and provide effective protection against infectious disease.

Additional recommendations for use of tetanus toxoid, reduced-content diphtheria toxoid, and acellular pertussis vaccine (Tdap)

The American Academy of Pediatrics and the Centers for Disease Control and Prevention are amending previous recommendations and making additional recommendations for the use of tetanus toxoid, reduced-content diphtheria toxoid, and acellular pertussis vaccine (Tdap). Review of the results from clinical trials and other studies has revealed no excess reactogenicity when Tdap is given within a short interval after other tetanus- or diphtheria-containing toxoid products, and accrual of postmarketing adverse-events reports reveals an excellent safety record for Tdap. Thus, the recommendation for caution regarding Tdap use within any interval after a tetanus- or diphtheria-containing toxoid product is removed. Tdap should be given when it is indicated and when no contraindication exists. In further efforts to protect people who are susceptible to pertussis, the American Academy of Pediatrics and Centers for Disease Control and Prevention recommend a single dose of Tdap for children 7 through 10 years of age who were underimmunized with diphtheria-tetanus-acellular pertussis (DTaP). Also, the age for recommendation for Tdap is extended to those aged 65 years and older who have or are likely to have contact with an infant younger than 12 months (eg, health care personnel, grandparents, and other caregivers).

The safety of immunizing with tetanus-diphtheria-acellular pertussis vaccine (Tdap) less than 2 years following previous tetanus vaccination: Experience during a mass vaccination campaign of healthcare personnel during a respiratory illness outbreak

BACKGROUND

Tdap is recommended for health care personnel (HCP) aged <65 years who received tetanus diphtheria or tetanus toxoid immunization (Td/TT) ≥2 years earlier. During a medical center Tdap vaccination campaign, we assessed the safety of use of a Td/TT to Tdap interval <2 years in HCP. We also describe reactogenicity in HCP who were aged ≥65 years or pregnant.

METHODS

HCP vaccinated with Tdap were surveyed to assess time since last Td/TT (≥2 years vs. <2 years), age, pregnancy status, and injection site adverse events (AEs) during the 2 weeks after Tdap. AE rates were calculated and compared by non-inferiority analysis using a predetermined margin of 10%. We searched clinic logbooks to assess for clinically important adverse events during the 2 months after Tdap.

RESULTS

Of the 4524 vaccinated HCP, 2221 (49.1%) completed a safety survey which met criteria for analysis. Non-inferiority analysis found that rates of moderate and/or severe injection site AEs were not significantly greater in those vaccinated <2 years than in those vaccinated ≥2 years after previous Td/TT. Three serious adverse events were reported during the 2 months after vaccination, none in persons who were ≥65 years, pregnant or received Td/TT <2 years before.

CONCLUSIONS

Our findings add to the body of evidence that a short interval between Td/TT and a single dose of Tdap is safe.

Boostrix: a reduced-dose acellular pertussis vaccine for use in adolescents and adults

Pertussis remains a serious problem in many countries. Even in countries with high vaccine coverage and a long vaccination history, pertussis outbreaks occur periodically. Rather than being a disease of young children, pertussis has shifted to affect adolescents and adults. Increased pertussis burden in adolescents and adults is the major source of severe infection for young infants. An effective vaccine is needed to control the spread of pertussis beyond preschool children. Boostrix is a reduced-dose acellular pertussis vaccine with diphtheria and tetanus toxoids, and is designed for use in adolescents and adults. Current evidence suggests that Boostrix is immunogenic and well tolerated. The pertussis component of Boostrix has been shown to be efficacious in a large-scale Phase III trial. More than 50 countries have given permit to the use of Boostrix, and many of them formally recommend the use of Boostrix in adolescents and adults. Designed as a vaccine for adolescence and adults, Boostrix has a long way to go to achieve large-scale use in those target groups. Nevertheless, we expect that the advent of Boostrix will lead to a much better control of pertussis in the general population.

Frequency of medically attended adverse events following tetanus and diphtheria toxoid vaccine in adolescents and young adults: a Vaccine Safety Datalink study

Background

Local reactions are the most commonly reported adverse events following tetanus and diphtheria toxoid (Td) vaccine and the risk of local reactions may increase with number of prior Td vaccinations.

Methods

To estimate the risk of medically attended local reactions following Td vaccination in adolescents and young adults we conducted a six-year retrospective cohort study assessing 436,828 Td vaccinations given to persons 9 through 25 years of age in the Vaccine Safety Datalink population from 1999 through 2004.

Results

Overall, the estimated risk of a medically attended local reaction was 3.6 events per 10,000 Td vaccinations. The lowest risk (2.8 events per 10,000 vaccinations) was found in the 11 to 15 year old age group. In comparison with that group, the event risks were significantly higher in both the 9 to 10 and 21 to 25 year old age groups. The risk of a local reaction was significantly higher in persons who had received another tetanus and diphtheria toxoid containing vaccine (TDCV) in the previous five years (incidence rate ratio, 2.9; 95% confidence interval, 1.2 to 7.2). Twenty-eight percent of persons with a local reaction to Td vaccine were prescribed antibiotics.

Conclusion

Medically attended local reactions were uncommon following Td vaccination. The risk of those reactions varied by age and by prior receipt of TDCVs. These findings provide a point of reference for future evaluations of the safety profile of newer vaccines containing tetanus or diphtheria toxoid.

Vaccine adherence in adolescents

Although a number of routine and catch-up vaccinations are currently recommended for adolescents, coverage rates of these vaccines are currently suboptimal. Routine recommended immunizations for this cohort include vaccines for influenza, human papillomavirus, and meningococcal disease, as well as a booster for tetanus, diphtheria, and acellular pertussis. Adolescence is also a critical period for administration of catch-up vaccines for those not fully immunized during childhood. Adolescents who do not seek appropriate preventive healthcare are at risk for significant morbidity and possible mortality. Increasing adolescent adherence to recommended vaccine schedules presents a challenge and opportunity for pediatricians and public health advocates. This article outlines barriers to vaccine compliance among adolescents and discusses strategies to increase vaccine uptake.

How much will it hurt? HPV vaccine side effects and influence on completion of the three-dose regimen

We examined the prevalence of reported pain following human papillomavirus (HPV) vaccination and whether it differed from that for other adolescent vaccines or affected completion of the HPV vaccine regimen. In 2008, we conducted cross-sectional surveys with parents of adolescent girls aged 11-20 living in areas of North Carolina with elevated cervical cancer rates who had received at least one dose of HPV vaccine. Pain from HPV vaccination, while commonly reported by parents, was less frequent compared to other adolescent vaccines and did not appear to affect vaccine regimen completion. These findings may be important to increase HPV vaccination coverage.

Risk of medically attended local reactions following diphtheria toxoid containing vaccines in adolescents and young adults: a Vaccine Safety Datalink study

Three vaccines currently recommended for adolescents (Tdap, Td, and MCV4 meningococcal conjugate vaccine) contain diphtheria toxoid. While the safety of individual diphtheria toxoid containing vaccines has been evaluated, less is known regarding the safety of administration of two or more of these vaccines, either concomitantly or sequentially. This study evaluated the risk of medically attended local reactions in adolescents and young adults with varying patterns of receipt of diphtheria toxoid containing vaccines. In general the risk of medically attended local reactions was low and did not differ with concomitant or sequential administration of diphtheria toxoid containing vaccines.

Adverse events after administration of tetanus-diphtheria-acellular pertussis vaccine to healthcare workers

Healthcare workers who received the tetanus-diphtheria-acellular pertussis (Tdap) vaccine were surveyed about adverse events. Local adverse events were more common among women and among those who received the Tdap vaccine less than 5 years after they had received the tetanus-diphtheria vaccine. Systemic adverse events were more common among healthcare workers aged less than 30 years. These findings provide guidance for counseling of healthcare workers who receive Tdap vaccine.

Pretravel consultation: rapid dipstick test as a decision guidance for the application of tetanus booster vaccinations

BACKGROUND

When deciding whether to administer a tetanus vaccination--for international travel or injury--a subject's vaccination certificate should be investigated. As many people lack valid vaccination cards and are unable to recall their vaccination history, the Tetanos Quick Stick (TQS) test rapidly detects protective tetanus immunoglobulin IgG antibodies in whole blood, serum, or plasma. This immunochromatographic dipstick test yields a positive or negative result.

METHODS

Our study evaluates the effectiveness of the TQS test by comparing the binary TQS test results of 100 sera with the tetanus antibody levels as measured by the standardized enzyme-linked immunosorbent assay (ELISA) method. We used the TQS test to determine whether a person needed a tetanus booster vaccination. If the test showed a clearly visible line that was similar to the control line, the result was determined to be positive.

RESULTS

All positive TQS test results had a concentration of IgG antibodies above 0.5 IU/mL as measured by ELISA, indicating that no booster vaccination was required. Similarly, in all cases with an antibody level below 0.1 IU/mL, where a vaccination would have been recommended based on the ELISA test result, the TQS test yielded a negative result. The positive predictive value and the specificity for the dipstick test were therefore 100%.

CONCLUSIONS

The TQS test is a reliable, fast, and cost-effective means of identifying subjects with a preexisiting level of tetanus IgG antibodies above approximately 0.5 IU/mL. This can help to avoid unnecessary tetanus vaccinations in travel clinics, emergency departments, and practices of family doctors.

Pertussis: not only a disease of childhood

INTRODUCTION

Pertussis is not just a childhood disease, but a respiratory infection that causes persistent cough in all age groups, from newborns to the elderly.

METHODS

The authors performed a selective literature search and reviewed national and international recommendations for treatment and vaccination.

RESULTS

Pertussis is found principally in young unvaccinated infants, but school-age children, adolescents, and adults are also affected. Up to 1% of infants contract pertussis, and their respiratory symptoms are often accompanied by apnea. School-age children occasionally display the coughing spasms typical of the disease. Annually, 0.2% to 0.5% of all adolescents and adults are infected and suffer from prolonged, frequently non-paroxysmal coughing. Severe and fatal cases of pertussis occur mainly in newborns and infants, and 25% of affected adults experience complications. Bordetella DNA may be detected by polymerase chain reaction (PCR) for four weeks after symptom onset; except in infants, the sensitivity of this diagnostic technique is low. Although the diagnosis can be confirmed by serological tests, the methods are not well standardized. Treatment with a macrolide prevents the spread of infection, but generally does not alleviate the symptoms. Combination vaccines are the most effective means of prophylaxis.

DISCUSSION

Pertussis is usually not included in the differential diagnosis of persistent respiratory symptoms. The considerable burden of disease could be reduced in adults and young infants by vaccinating adults with acellular combination vaccines.

Tetanus-diphtheria-acellular pertussis vaccination of adults in the USA

Pertussis is an important cause of morbidity and mortality, and its incidence has been increasing in adolescents and adults over the past two decades. Waning immunity in adolescents and adults may be partially responsible. Adults can suffer significant illness from pertussis and its complications, such as pneumonia, rib fractures and syncope. Moreover, adults serve as a source of disease for infants, who are more vulnerable to severe complications and even death. The economic burden of pertussis is substantial, in terms of both medical and nonmedical costs. Fortunately, the burden of pertussis disease can now be safely and effectively reduced by vaccinating adults with tetanus-diphtheria-acellular pertussis (Tdap) vaccine. Further research is needed to elucidate the role of vaccination in pregnant women and those over 65 years of age, and also to determine whether further booster doses of Tdap are needed.

Pertussis vaccination for health care workers

Pertussis, an acute respiratory infection caused by Bordetella pertussis, classically manifests as a protracted cough illness. The incidence of pertussis in the United States has been increasing in recent years. Immunity wanes after childhood vaccination, leaving adolescents and adults susceptible to infection. The transmission of pertussis in health care settings has important medical and economic consequences. Acellular pertussis booster vaccines are now available for use and have been recommended for all adolescents and adults. These vaccines are safe, immunogenic, and effective. Health care workers are a priority group for vaccination because of their increased risk of acquiring infection and the potential to transmit pertussis to high-risk patients. Health care worker vaccination programs are likely to be cost-effective, but further research is needed to determine the acceptability of pertussis vaccines among health care workers, the duration of immunity after booster doses, and the impact of vaccination on the management of pertussis exposures in health care settings.

New, and some not-so-new, vaccines for adolescents and diseases they prevent

Adolescents in the United States now have the opportunity to receive new vaccines that prevent invasive meningococcal infections, pertussis (whooping cough), and cervical cancer. Except for their potential to cause serious illness, these infections could not be more different. Their incidence ranges from extremely low to quite high. Early clinical manifestations of infection range from none to life-threatening illness. Two of the vaccines are similar to those already in use, whereas 1 is completely new. In conjunction with the 4 vaccines previously recommended for adolescents (the tetanus and diphtheria booster, hepatitis B, measles-mumps-rubella, and varicella), the 3 new vaccines (meningococcal, human papillomavirus, and the tetanus-diphtheria-pertussis booster [which replaced the tetanus-diphtheria booster]) bring the number recommended for adolescents to 6. In this article, we describe key characteristics of the 3 new vaccines and infections they were designed to prevent. We also briefly discuss other vaccines recommended for all adolescents who have not already received them and new vaccines that are still under development.

Emergency department staff and susceptibility to pertussis: a seroprevalence study

OBJECTIVE

To determine the proportion of ED staff who are susceptible to pertussis. There was evidence that some winter leave in southern Tasmania might be a reason of pertussis infection among unimmunized staff. This results in loss of individual earning and loss of availability of staff during the peak demand periods in the ED. There is evidence in the literature that underdiagnosis and undertreatment of pertussis occurs worldwide.

METHODS

All ED staff were approached to participate in this seroprevalence study. A self-completed questionnaire was used to record pervious immunization history for pertussis. Blood samples were collected and analysed to detect and quantify immunoglobulin G and immunoglobulin A titres for pertussis. All confidence intervals (CI) are at 95%.

SETTINGS

The Royal Hobart Hospital and the co-located Hobart Private Hospital.

RESULTS

Ninety-seven of 106 eligible staff took part in the present study, a participation rate of 92% (CI 84-96). Ninety-one of 97 subjects (94%, CI 87-98) believed that they had been immunized for pertussis in childhood; six subjects had either not been immunized or were unsure (6%, CI 2-13). Twenty-three subjects (24%, CI 16-33) had been immunized as adults. There was serologic evidence of recent infection for 21 participants (22%, CI 14-31). Thirty-one participants (32%, CI 23-42) were susceptible to pertussis on the basis of low immunoglobulin G titres.

CONCLUSION

ED staff should routinely be offered booster immunization for pertussis.

A "new age" in pertussis prevention new opportunities through adult vaccination

BACKGROUND

For the first time, pertussis vaccines for adolescents and adults (combined with tetanus and diphtheria toxoids [Tdap]) became available in the United States in 2005. Despite a fully implemented U.S. childhood pertussis vaccination program, substantial morbidity because of pertussis continues to occur. To reduce this morbidity, the Advisory Committee on Immunization Practices recommended Tdap for all adolescents and adults in place of the next tetanus-diphtheria booster. As background for the basis of these recommendations, we summarize data on the morbidity and incidence of pertussis in U.S. adults and the role of adults in transmitting pertussis to young infants.

METHODS

A MEDLINE search was performed in March 2006 for data on pertussis incidence rates and cough illness because of pertussis among U.S. adults (prospective, nonoutbreak studies were selected) and pertussis complications in adults. Data from the national passive surveillance system were also analyzed in October 2005.

RESULTS

The true adult burden is estimated at more than 600,000 cases annually in the United States. Adults with pertussis commonly cough for 2-4 months, often resulting in repeated medical visits and missed work. Complications include pneumonia, rib fractures, and cough syncope. Adults are an important source of pertussis for young infants, who have the highest risk of hospitalization and death.

CONCLUSIONS

The morbidity from pertussis in adults can be substantial, the incidence of pertussis in U.S. adults is high, and adults transmit infection to young infants. Providers now have the opportunity to reduce the burden of pertussis by vaccinating adults with Tdap.

Prevention of pertussis: Recommendations derived from the second Global Pertussis Initiative roundtable meeting

The Global Pertussis Initiative (GPI) was established in 2001 to assess the global extent of the ongoing problem of pertussis and to evaluate and prioritize pertussis control strategies. Exchange of data, knowledge, and experience, facilitated by discussion and debate, resulted in the formulation, in 2002, of the following recommendation: all countries should consider expanding existing vaccination strategies to include adding pertussis booster doses to pre-school children (4-6 years old), to adolescents, and to those specific adults that have the highest risk of transmitting Bordetella pertussis infection to vulnerable infants. The GPI met again in 2005, where it reinforced its previous recommendation for universal adolescent immunization. Additionally, the GPI recommended implementation of the cocoon strategy (immunization of family members and close contacts of the newborn) in countries where it is economically feasible, and encouraged efforts toward global standardization of pertussis disease clinical definitions and diagnostics. Universal adult vaccination is a logical goal for the ultimate elimination of pertussis disease, but feasibility issues remain obstacles to implementation.

Immunization update

Although the development and licensure of new vaccines over the last 2 years has generated a lot of excitement as well as debate, there is a lot more to come. Not discussed in this article. licensure of another long-awaited vaccine albeit for use in adults was that for herpes zoster. The second HPV and rotavirus vaccines are awaiting approval in the US. Next in line are the vaccines both prophylactic as well as therapeutic against HIV. Topics of debate over the new vaccines include discussions amongst practices as to the affordability and cost of the new vaccines as well as the ethical debate amongst lawmakers and the general public regarding the rights and wrongs of compulsory vaccination against HPV. Another ongoing discussion is regarding the availability of approved vaccines. Shortages have been seen with several of the childhood vaccines including heptavalent pneumococcal conjugate vaccine, tetravalent meningococcal conjugate vaccine, hepatitis A vaccine, as well as the ongoing saga with influenza vaccines. Across the globe while the struggle against polio continues, there is encouraging news regarding the reduction in measles-related deaths, particularly in Africa. The last few years have indeed been landmark years in infectious disease research as the search continues for better and safer vaccines globally.