-
Cell Host & Microbe May 2020The live-attenuated oral poliovirus vaccine (OPV or Sabin vaccine) replicates in gut-associated tissues, eliciting mucosa and systemic immunity. OPV protects from...
The live-attenuated oral poliovirus vaccine (OPV or Sabin vaccine) replicates in gut-associated tissues, eliciting mucosa and systemic immunity. OPV protects from disease and limits poliovirus spread. Accordingly, vaccination with OPV is the primary strategy used to end the circulation of all polioviruses. However, the ability of OPV to regain replication fitness and establish new epidemics represents a significant risk of polio re-emergence should immunization cease. Here, we report the development of a poliovirus type 2 vaccine strain (nOPV2) that is genetically more stable and less likely to regain virulence than the original Sabin2 strain. We introduced modifications within at the 5' untranslated region of the Sabin2 genome to stabilize attenuation determinants, 2C coding region to prevent recombination, and 3D polymerase to limit viral adaptability. Prior work established that nOPV2 is immunogenic in preclinical and clinical studies, and thus may enable complete poliovirus eradication.
Topics: Adult; Animals; Chlorocebus aethiops; Disease Models, Animal; Female; Genetic Engineering; HeLa Cells; Humans; Immunogenicity, Vaccine; Male; Mice; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Oral; RNA, Viral; RNA-Dependent RNA Polymerase; Recombination, Genetic; Vaccination; Vaccines, Attenuated; Vero Cells; Virulence
PubMed: 32330425
DOI: 10.1016/j.chom.2020.04.003 -
BMJ (Clinical Research Ed.) Jun 2023To test for potential non-specific effects of an additional, early measles, mumps, and rubella (MMR) vaccine at age 5-7 months on risk of infection related... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
To test for potential non-specific effects of an additional, early measles, mumps, and rubella (MMR) vaccine at age 5-7 months on risk of infection related hospitalisation before age 12 months.
DESIGN
Randomised, double blinded, placebo controlled trial.
SETTING
Denmark, a high income setting with low exposure to MMR.
PARTICIPANTS
6540 Danish infants aged 5 to 7 months.
INTERVENTIONS
Infants were randomly allocated 1:1 to intramuscular injection with standard titre MMR vaccine (M-M-R VaxPro) or placebo (solvent only).
MAIN OUTCOME MEASURES
Hospitalisations for infection, defined as all hospital contacts of infants referred from primary care for hospital evaluation and with an infection diagnosed, analysed as recurrent events, from randomisation to 12 months of age. In secondary analyses implications of censoring for date of subsequent diphtheria, tetanus, pertussis, polio, type B, and immunisation with pneumococci conjugate vaccine (DTaP-IPV-Hib+PCV), potential effect modification by sex, prematurity (<37 weeks' gestation), season, and age at randomisation were tested, and the secondary outcomes of hospitalisations ≥12 hours and antibiotic use were evaluated.
RESULTS
6536 infants were included in the intention-to-treat analysis. 3264 infants randomised to MMR vaccine experienced 786 hospitalisations for infection before age 12 months compared with 762 for the 3272 infants randomised to placebo. In the intention-to-treat analysis the rate of hospitalisations for infection did not differ between the MMR vaccine and placebo groups (hazard ratio 1.03, 95% confidence interval 0.91 to 1.18). For infants randomised to MMR vaccine compared with those randomised to placebo, the hazard ratio of hospitalisations for infection with a duration of at least 12 hours was 1.25 (0.88 to 1.77), and for prescriptions of antibiotics was 1.04 (0.88 to 1.23). No significant effect modifications were found by sex, prematurity, age at randomisation, or season. The estimate did not change when censoring at the date infants received DTaP-IPV-Hib+PCV after randomisation (1.02, 0.90 to 1.16).
CONCLUSION
Findings of this trial conducted in Denmark, a high income setting, do not support the hypothesis that live attenuated MMR vaccine administered early to infants aged 5-7 months decreases the rate of hospitalisations for non-targeted infection before age 12 months.
TRIAL REGISTRATION
EU Clinical Trials Registry EudraCT 2016-001901-18 and ClinicalTrials.gov NCT03780179.
Topics: Infant; Humans; Measles-Mumps-Rubella Vaccine; Mumps; Diphtheria-Tetanus-Pertussis Vaccine; Poliovirus Vaccine, Inactivated; Measles; Immunization; Hospitalization; Haemophilus Vaccines
PubMed: 37286215
DOI: 10.1136/bmj-2022-072724 -
Best Practice & Research. Clinical... Oct 2021Neonatal immunisation includes vaccination in the first 4 weeks of life (Neonatal period) as well as in high-risk preterm infants in the first few months (until 44 weeks... (Review)
Review
Neonatal immunisation includes vaccination in the first 4 weeks of life (Neonatal period) as well as in high-risk preterm infants in the first few months (until 44 weeks corrected gestational age). Neonates have an immature immune system, which renders them highly susceptible to life-threatening infections. This highlights the importance of vaccination in this vulnerable population; however, at the same time also making it challenging because of their inability to generate a protective immune response. Other challenges include interference from maternal antibodies and excessive skewing towards T Helper Cell Type 2 (Th2) immunity. Despite these challenges, several vaccines have been developed and proven safe and effective at birth. Presently, there are 3 vaccines - Hepatitis B vaccine, Bacillus Calmette-Guerine (BCG) and Oral Polio vaccine (OPV) widely used in neonates, which provides evidence that certain antigen-adjuvant combinations can elicit protective neonatal responses. This review focusses on current vaccinations in neonates, including preterm infants and highlights some novel approaches to enhance neonatal vaccination.
Topics: Humans; Infant; Infant, Newborn; Infant, Premature; Poliovirus Vaccine, Oral; Vaccination
PubMed: 33129673
DOI: 10.1016/j.bpobgyn.2020.09.004 -
The Medical Letter on Drugs and... Oct 2022
Topics: Adult; Haemophilus Vaccines; Humans; Immunization Schedule; Infant; Poliovirus Vaccine, Inactivated; Vaccination
PubMed: 36206162
DOI: No ID Found -
Bulletin of the World Health... Dec 2023A decrease in vaccine coverage in conflict-affected areas has placed Yemen at higher risk of polio outbreaks caused by vaccine-derived poliovirus strains.
PROBLEM
A decrease in vaccine coverage in conflict-affected areas has placed Yemen at higher risk of polio outbreaks caused by vaccine-derived poliovirus strains.
APPROACH
In response to polio outbreaks, the Yemeni health ministry and partners initiated multiple vaccination campaigns to deliver vaccines to children. We also implemented several measures to enhance communication, education, health promotion and hygiene, especially in camps for internally displaced people.
LOCAL SETTING
In 2009, Yemen achieved polio-free status and maintained it until 2019. However, the ongoing political conflict since 2015, coupled with challenges in delivering the polio vaccine to conflict-affected areas, resulted in two polio outbreaks: 35 cases caused by vaccine-derived poliovirus strain 1 between 2019 and 2021, and 230 cases due to vaccine-derived poliovirus strain 2 between November 2021 and December 2022.
RELEVANT CHANGES
In response to the first outbreak, by the end of 2020, we vaccinated 7.2 million children through nationwide vaccination campaigns, except in Sa'ada governorate due to a ban by the authorities. By the end of 2021, 3 800 313 children younger than 5 years had received polio vaccines. For the second outbreak, by the end of 2022, 4 463 389 vaccines had been given to children younger than 10 years, and 1 217 423 to those younger than 5 years.
LESSONS LEARNT
Vaccination campaigns in conflict-affected areas with low vaccine coverage remain crucial in eradicating polio. Efforts are needed to reach vulnerable groups such as displaced populations. Advocacy, communication and social mobilization actions help ensure broader public inclusion and participation in vaccination efforts to prevent polio outbreaks.
Topics: Child; Humans; Yemen; Poliomyelitis; Poliovirus; Poliovirus Vaccines; Disease Outbreaks
PubMed: 38024246
DOI: 10.2471/BLT.23.290122 -
Pediatrics May 2022The majority of children are prescribed antibiotics in the first 2 years of life while vaccine-induced immunity develops. Researchers have suggested a negative...
BACKGROUND
The majority of children are prescribed antibiotics in the first 2 years of life while vaccine-induced immunity develops. Researchers have suggested a negative association of antibiotic use with vaccine-induced immunity in adults, but data are lacking in children.
METHODS
From 2006 to 2016, children aged 6 to 24 months were observed in a cohort study. A retrospective, unplanned secondary analysis of the medical record regarding antibiotic prescriptions and vaccine antibody measurements was undertaken concurrently. Antibody measurements relative to diphtheria-tetanus-acellular pertussis (DTaP), inactivated polio (IPV), Haemophilus influenzae type b (Hib), and pneumococcal conjugate (PCV) vaccines were made.
RESULTS
In total, 560 children were compared (342 with and 218 without antibiotic prescriptions). Vaccine-induced antibody levels to several DTaP and PCV antigens were lower (P < .05) in children given antibiotics. A higher frequency of vaccine-induced antibodies below protective levels in children given antibiotics occurred at 9 and 12 months of age (P < .05). Antibiotic courses over time was negatively associated with vaccine-induced antibody levels. For each antibiotic course the child received, prebooster antibody levels to DTaP antigens were reduced by 5.8%, Hib by 6.8%, IPV by 11.3%, and PCV by 10.4% (all P ≤ .05), and postbooster antibody levels to DTaP antigens were reduced by 18.1%, Hib by 21.3%, IPV by 18.9%, and PCV by 12.2% (all P < .05).
CONCLUSIONS
Antibiotic use in children <2 years of age is associated with lower vaccine-induced antibody levels to several vaccines.
Topics: Anti-Bacterial Agents; Antibodies, Viral; Child; Child, Preschool; Cohort Studies; Diphtheria-Tetanus-acellular Pertussis Vaccines; Haemophilus Vaccines; Humans; Poliovirus Vaccine, Inactivated; Retrospective Studies; Vaccines, Combined
PubMed: 35474546
DOI: 10.1542/peds.2021-052061 -
Nature Reviews. Immunology Dec 2021In August 2020, Africa was declared free of poliomyelitis (polio), bringing to fruition a goal that took more than 30 years to achieve. This Perspective chronicles... (Review)
Review
In August 2020, Africa was declared free of poliomyelitis (polio), bringing to fruition a goal that took more than 30 years to achieve. This Perspective chronicles global, continental, national and community actions taken by diverse stakeholders that finally led to the elimination of transmission of wild poliovirus in Africa. The cascade of events started with the development of polio vaccines and the realization that polio, much like smallpox, could be eradicated. After a 1988 pledge by the World Health Assembly to eradicate polio globally, concerted and deliberate efforts were made in Africa to achieve this goal. This included the use of evidence-based approaches for the harmonization and standardization of public health strategies, using a network of polio laboratories and emergency operation centres and actively pursuing underserved populations. Innovative solutions to counter challenges such as conflict and vaccine hesitancy may be of use in future public health interventions.
Topics: Africa; Animals; Disease Eradication; Global Health; Humans; Poliomyelitis; Poliovirus Vaccines; Vaccination Hesitancy
PubMed: 34697501
DOI: 10.1038/s41577-021-00640-w -
Current Opinion in Infectious Diseases Oct 2020Focusing on the key developments since January 2019, this review aims to inform policymakers and clinical practitioners on the latest on evolving global polio... (Review)
Review
PURPOSE OF REVIEW
Focusing on the key developments since January 2019, this review aims to inform policymakers and clinical practitioners on the latest on evolving global polio epidemiology and scientific advancements to guide strategies for eradication.
RECENT FINDINGS
An upsurge in wild poliovirus type 1 cases in Pakistan and Afghanistan and an expansion of type 2 circulating vaccine-derived poliovirus transmission in multiple countries threaten the remarkable progress made over past several decades by the global eradication program. These challenges have also spurred innovation on multiple fronts, including earlier detection, enhanced environmental surveillance and safer and more affordable vaccine options.
SUMMARY
A concerted effort to adapt program strategies to address context-specific challenges and continued focus on innovations to enhance detection and response capabilities will be the key to achieve and sustain eradication of all types of polioviruses.
Topics: Afghanistan; Disease Eradication; Global Health; Humans; Immunization Programs; Molecular Epidemiology; Pakistan; Poliomyelitis; Poliovirus; Poliovirus Vaccines; RNA, Viral
PubMed: 32773500
DOI: 10.1097/QCO.0000000000000667 -
The Lancet. Global Health Aug 2021The Global Polio Eradication Initiative, launched in 1988 with anticipated completion by 2000, has yet to reach its ultimate goal. The recent surge of polio cases... (Review)
Review
The Global Polio Eradication Initiative, launched in 1988 with anticipated completion by 2000, has yet to reach its ultimate goal. The recent surge of polio cases urgently calls for a reassessment of the programme's current strategy and a new design for the way forward. We propose that the sustainable protection of the world population against paralytic polio cannot be achieved simply by stopping the circulation of poliovirus but must also include maintaining high rates of population immunity indefinitely, which can be created and maintained by implementing global immunisation programmes with improved poliovirus vaccines that create comprehensive immunity without spawning new virulent viruses. The proposed new strategic goal of eradicating the disease rather than the virus would lead to a sustainable eradication of poliomyelitis while simultaneously promoting immunisation against other vaccine-preventable diseases.
Topics: Disease Eradication; Global Health; Humans; Immunization Programs; Poliomyelitis; Poliovirus Vaccines; Program Evaluation
PubMed: 34118192
DOI: 10.1016/S2214-109X(21)00205-9 -
MMWR. Morbidity and Mortality Weekly... Jul 2023This report describes the status of introductions globally for eight World Health Organization (WHO)-recommended new and underutilized vaccines, comprising 10 individual...
This report describes the status of introductions globally for eight World Health Organization (WHO)-recommended new and underutilized vaccines, comprising 10 individual vaccine antigens. By 2021, among 194 countries worldwide, 33 (17%) provided all of these 10 WHO-recommended antigens as part of their routine immunization schedules; only one low-income country had introduced all of these recommended vaccines. Universal hepatitis B birth dose; human papillomavirus vaccine; rotavirus vaccine; and diphtheria, tetanus, and pertussis-containing vaccine first booster dose have been introduced by 57%, 59%, 60%, and 72% of all countries worldwide, respectively. Pneumococcal conjugate vaccine, rubella-containing vaccine, measles-containing vaccine second dose, and Haemophilus influenzae type b vaccine have been introduced by 78%, 89%, 94%, and 99% of all countries, respectively. The annual rate of new vaccine introductions declined precipitously when the COVID-19 pandemic started, from 48 in 2019 to 15 in 2020 before rising to 26 in 2021. Increased efforts to accelerate new and underutilized vaccine introductions are urgently needed to improve universal equitable access to all recommended vaccines to achieve the global Immunization Agenda 2021-2030 (IA2030) targets.
Topics: Humans; Infant; Diphtheria-Tetanus-Pertussis Vaccine; Pandemics; Haemophilus Vaccines; COVID-19; Vaccination; Measles Vaccine; Rubella Vaccine; Immunization Schedule; Poliovirus Vaccine, Inactivated; Hepatitis B Vaccines; Vaccines, Combined
PubMed: 37410663
DOI: 10.15585/mmwr.mm7227a2