Investigation of adverse events following bacille Calmette-Guérin immunization using immunization safety surveillance system in Korea Centers for Disease Control and Prevention

Microneedle-mediated intradermal delivery of Bacille Calmette-Guérin (BCG) vaccines for single-dose tuberculosis vaccination

Tuberculosis (TB) remains a highly lethal infectious disease. The primary preventive measure is Bacille Calmette-Guérin (BCG), a live attenuated vaccine. However, the current intradermal vaccination method with 10-dose vials faces challenges such as inadequate infant injection, inaccurate dispensing, and unstable storage. Researchers have explored microneedle (MN) technology to address these concerns as a intradermal vaccine delivery approach. MN array patches offer painless administration, convenience, improved immunogenicity, and vaccine stability. This study aimed to develop a coated MN system using a micro-dispensing technique at a low temperature (4 °C) and specific excipients for precise dosing and vaccine viability enhancement. Long-term storage stability revealed enhanced storage stability of the BCG-coated MN (BCG-MN) vaccine, maintaining a survival rate of over 60 % for 8 weeks at -20 °C. In vivo vaccination tests using BCG-MN vaccines on guinea pigs exhibited no adverse reactions. Moreover, the BCG-MN vaccine demonstrated superior immune response compared to injections, suggesting that this BCG vaccine-coated MN platform has the potential as a single-dose TB vaccination technology, offering precise dosing control and enhanced immune effectiveness with high storage stability.

Spectrum and Incidence of Adverse Reactions Post Immunization in the Taiwanese Population (2014-2019): An Analysis Using the National Vaccine Injury Compensation Program

Background: Post-marketing surveillance is crucial for gathering data on vaccine reactogenicity, enhancing public trust in immunization, and promoting vaccine uptake. This study aims to characterize adverse events following immunization (AEFIs) and estimate the incidence rates of adverse reactions (ARs) associated with vaccines included in Taiwan's Expanded Program on Immunization (EPI). This study utilizes data from Taiwan's Vaccine Injury Compensation Program (VICP). Methods: Vaccine injury claims submitted to the VICP between 2014 and 2019 were analyzed. ARs were defined as AEFIs adjudicated as "related" or "indeterminate" by the VICP committee. Data on the annual number of vaccine doses administered were obtained from the Taiwan CDC, which helped calculate the AR incidence rates. Results: A total of 491 AEFI claims were reviewed, with 327 (66.6%) categorized as ARs. The AEFIs were mainly associated with the Bacillus Calmette-Guérin (BCG) vaccine (43.4%) and the seasonal influenza vaccine (22.0%). Most EPI vaccines demonstrated low AR incidence rates, ranging from 1.68 to 13.6 per million doses, with the exception of BCG, which exhibited 162.5 ARs per million doses. Shifting BCG immunization from below 5 months to at least 5 months reduced osteomyelitis incidence significantly, from 41.4 to 7.9 (p = 0.0014), but increased abscess and lymphadenitis cases. Conclusions: EPI vaccines in Taiwan are highly safe, with minimal AR incidences in the general population. The BCG vaccine remains an exception, occasionally causing severe ARs like osteomyelitis. Adjusting the immunization schedule to an older age may mitigate some of these adverse effects.

Vaccines and allergy: Back to the right places

Hypersensitivity reactions represent one of the most common causes of hesitancy for adherence to national vaccination programs. The majority of hypersensitivity reactions after vaccination are mild, and anaphylaxis is reported to be rare, although it remains challenging to estimate the frequency attributed to each single vaccine, either because of the lower number of administered doses of less common vaccines, or the administration of simultaneous vaccine in most of the vaccination programs. Although literature remains scattered, international consensus guides clinicians in identifying patients who might need the administration of vaccines in protected environments due to demonstrated hypersensitivity to vaccine components or adjuvants. Here we provide the current guidance on hypersensitivity reactions to vaccines and on vaccination of children with allergy disorders.

The safety of BCG revaccination in the context of COVID-19

The bacille Calmette-Guérin (BCG) vaccine is administered in many countries as part of their vaccination schedules. Epidemiologic studies have suggested a possible benefit of this vaccine in the context of the COVID-19 pandemic and other respiratory infections. We aimed to assess the safety of this intervention in BCG-primed adults. Adult health care workers (n = 451) received a single intradermal application of the BCG vaccine (Tokyo 172 strain) in the deltoid region of the right arm. Follow-up (30 days) calls and clinical inspections were guided using a standardized data sheet to assess local and systemic reactions. Early local reactions were common at 24 h and 7 days, such as erythema (74.9%, 69.2%), induration (55.7%, 59%), a papule (53.4%, 47.7%), and edema (48.3%, 38.1). Local symptoms (pruritus 44.8%, heat 16.2%, and pain 34.8%) were less frequent at day 7. Late expected reactions (14 and 30 days) included the formation of crusts (39.6% and 63.9%), a pustule (36.6% and 17%), or ulcers (28.8% and 17.7%). Severe reactions were limited to subcutaneous abscesses (2%) and lymphadenitis (<1%).

Bacillus Calmette-Guérin Vaccine-Related Osteomyelitis in Immunocompetent Children in Saudi Arabia: A Narrative Review

The Bacillus Calmette-Guérin (BCG) vaccine is the most frequently used live-attenuated vaccine worldwide. Since 2002, two BCG vaccination strains, Pasteur 1173 P2 and Tokyo 172-1, have been the mainstay of Saudi Arabian healthcare. In 2005, the Danish 1331 strain was first used as the principal strain in clinical trials. Children can develop osteomyelitis 4-24 months after immunization with the BCG vaccine, an uncommon but serious side effect in immunocompetent children. We conducted this study to review the epidemiology, diagnosis, clinical symptoms, laboratory analyses, imaging features, and management of BCG osteomyelitis in immunocompetent children. Long bone metaphyses and epiphyses are more frequently affected. The diagnosis of BCG osteomyelitis is difficult because the symptoms are vague and subtle, and the duration between presentation and vaccination may range from a few months to a year. Radiography and computed tomography scans for BCG osteomyelitis typically show a devastating lesion with an associated periosteal response. Magnetic resonance imaging frequently reveals a large interosseous abscess indicative of osteomyelitis. There are no current treatment guidelines for BCG osteomyelitis in Saudi Arabia, but antituberculous regimens, particularly isoniazid and rifampicin, have been found to be very effective in previous studies. Although older studies did not favor surgical intervention because of the risk of complications, a few studies performed minor surgical interventions and had good outcomes. As BCG osteomyelitis is an infrequent complication, especially in immunocompetent children, its diagnosis is time-consuming. Therefore, it is critical to inform healthcare workers of this possible complication to make the diagnosis more straightforward and avoid confusion with pyogenic osteomyelitis. As only a few cases have been reported, further studies in Saudi Arabia are required for evidence-based guidelines applicable to actual practice to be established.

Efficacy and Safety of BCG Revaccination With M. bovis BCG Moscow to Prevent COVID-19 Infection in Health Care Workers: A Randomized Phase II Clinical Trial

The Bacillus Calmette-Guérin (BCG) vaccine, which is widely used to protect children against tuberculosis, can also improve immune response against viral infections. This unicentric, randomized-controlled clinical trial assessed the efficacy and safety of revaccination with BCG Moscow in reducing the positivity and symptoms of COVID-19 in health care workers (HCWs) during the COVID-19 pandemic. HCWs who had negative COVID-19 IgM and IgG and who dedicated at least eight hours per week in facilities that attended to individuals suspected of having COVID-19 were included in the study and were followed for 7, 15, 30, 60, and 180 days by telemedicine. The HCWs were randomly allocated to a revaccinated with BCG group, which received the BCG vaccine, or an unvaccinated group. Revaccination with BCG Moscow was found to be safe, and its efficacy ranged from 30.0% (95.0%CI -78.0 to 72.0%) to 31.0% (95.0%CI -74.0 to 74.0%). Mycobacterium bovis BCG Moscow did not induce NK cell activation at 15–20 days post-revaccination. As hypothesized, revaccination with BCG Moscow was associated with a lower incidence of COVID-19 positivity, though the results did not reach statistical significance. Further studies should be carried out to assess whether revaccination with BCG is able to protect HCWs against COVID-19. The protocol of this clinical trial was registered on August 5th, 2020, at REBEC (Registro Brasileiro de Ensaios Clínicos, RBR-4kjqtg - ensaiosclinicos.gov.br/rg/RBR-4kjqtg/1) and the WHO (# U1111-1256-3892). The clinical trial protocol was approved by the Comissão Nacional de ética de pesquisa- CONEP (CAAE 31783720.0.0000.5078).

Epidemiological characteristics and trends of Bacillus Calmette-Guérin lymphadenitis in Shanghai, China from 2010 to 2019

Although the administration of the Bacillus Calmette–Guérin (BCG) vaccine is generally safe, lymphadenitis, the most common complication of BCG vaccination, can occur. Here, we describe the epidemiological characteristics and incidence trends of BCG lymphadenitis in Shanghai, China, among a population with a high burden of tuberculosis. A total of 56 cases of adverse events following immunization (AEFI) after BCG vaccination were reported in Shanghai, including 51 cases of BCG lymphadenitis (91.07%), from 2010 to 2019. The general incidence of BCG lymphadenitis was 173 per 1,000,000 doses in Shanghai from 2010 to 2019. A nonsignificant increase of 58.81% per year was observed between 2010 and 2012 (t = 0.93; p = .40), followed by a significant decline of 28.00% per year from 2012 to 2019 (t = −4.27; p < .01). Seven batches of BCG vaccines triggered three or more BCG lymphadenitis cases, for 27 (52.94%) cases in total. We identified two patients with immunodeficiency of chronic granulomatous disease, one of whom died four years later after BCG vaccination and another of whom was still being treated after two transplants. The average total care cost of the 47 recovered cases was 11,336 RMB (range: 2,637–33,861 RMB). Due to the high burden of BCG lymphadenitis, especially in children with immunodeficiency, it is suggested that government departments should strengthen healthcare provider training, assign specific nurses to perform BCG vaccination, monitor vaccinated individuals actively and timely detect abnormal signals so as to reduce the incidence of BCG lymphadenitis.

Risks of ACTH therapy for West syndrome following BCG vaccination

OBJECTIVE

Bacille de Calmette et Guérin (BCG) is a live vaccine for tuberculosis that is administered to all infants in Japan. Adrenocorticotropic hormone (ACTH) therapy for West syndrome (WS) causes immunosuppression and may result in BCG infection after BCG vaccination. We evaluated the safety of ACTH therapy initiated shortly after BCG vaccination.

METHODS

We analyzed patients with WS who received ACTH therapy between 2005 and 2018. We evaluated the interval between BCG and ACTH therapy, and the rate of BCG infection during and after ACTH therapy, by retrospective chart review.

RESULTS

Seventy-nine patients were included in the analysis. Twenty-three patients received ACTH therapy prior to BCG vaccination. For the remaining 56 patients, the median interval between BCG vaccination and the start of ACTH therapy (BCG-ACTH interval) was 91.5 (range 14-280) days. The BCG-ACTH interval was shorter in patients with unknown than in those with known etiologies. It was <8 weeks in 13 patients (10 with unknown and 3 with known etiologies). The minimum BCG-ACTH interval was 14 days. Six patients with epileptic spasms received BCG vaccinations because physicians did not recognize their seizures. None of the patients developed BCG infection.

CONCLUSION

No patients who received ACTH therapy after BCG, even at an interval of 8 weeks, developed BCG infection. The timing of ACTH therapy initiation should be based on the risk of BCG-related adverse events and the adverse effects of any delay.