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Introducción: En el Perú, el programa actual de inmunización para COVID-19 comprende las vacunas BBIBP-CorV, BNT162B2 y ChAdOx1 nCoV-19. Si bien el esquema de inmunización es de dos dosis, algunos países han incluido recientemente una dosis de refuerzo a su esquema. Métodos: Se realizó una búsqueda de evidencia científica sobre la eficacia y seguridad de la vacunación de refuerzo con la vacuna BNT162b2 en población con esquema de vacunación completa para COVID-19 en Perú. Evidencia incluida: Se consideraron cuatro documentos de recomendación basados en evidencia, un estudio observacional y tres ensayos clínicos fase III en curso. Conclusión: A la fecha, no existe evidencia suficiente sobre la eficacia de agregar una dosis de refuerzo al esquema de inmunización para COVID-19. La evidencia disponible no permite justificar el uso de una dosis de refuerzo con la vacuna BNT162B2 en población que recibió previamente dos dosis de las vacunas anteriormente mencionadas.
Introduction: In Peru, the current immunization schedule for COVID-19 comprises BBIBP-CorV, BNT162B2 and ChAdOx1 nCoV-19 vaccines. Although the immunization schedule is two doses, some countries have recently included a booster dose to their schedule. Methods: A search for scientific evidence on the efficacy and safety of booster vaccination with BNT162b2 vaccine in a population with a complete vaccination schedule for COVID-19 in Peru was performed. Evidence included: Four evidence-based recommendation documents, one observational study and three ongoing phase III clinical trials were considered. Conclusion: To date, there is insufficient evidence on the efficacy of adding a booster dose to the immunization schedule for COVID-19. The available evidence does not justify the use of a booster dose of BNT162B2 vaccine in a population that previously received two doses of the aforementioned vaccines.
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Abstract: Objective: To asses the non-inferiority between two different vaccination schedules one month after the administration of the third dose. Materials and methods: We evaluated the anti-HPV 16/18 antibody titers induced by quadrivalent HPV vaccine administered using two different schedules in girls 9 to 10-year-old girls: a traditional (0-2-6) and an alternative (0-6-50). Blood samples were collected at month 7, 21 and 51. Results: The antibody geometric mean titer ratios one month after the application of the third dose -month 51 for the alternative and month 7 for the traditional- were 1.55 for HPV16 (95%CI, 1.15-2.08) and 1.53 for HPV18 (95%CI, 1.12-2.09). The seropositive rate was above 99% in both groups. Conclusions: The application of an alternative 3-dose schedule in 9 to 10-year-old girls induces a non-inferior immune response compared to the standard one month after the last dose. Further research is needed to understand the minimal number of doses and their timing to provide the best coverage for HPV infection.
Resumen: Objetivo: Evaluar la no inferioridad entre dos diferentes esquemas de vacunación un mes después de la administración de la tercera dosis. Material y métodos: Se evaluaron los títulos de anticuerpos anti-VPH 16/18 inducidos por la vacuna contra VPH tetravalente administrada en niñas de 9 a 10 años utilizando dos esquemas diferentes: tradicional (0-2-6) y alternativo (0-6-50). Se recolectaron muestras en los meses 7, 21 y 51. Resultados: La media geométrica de títulos de anticuerpos un mes después de la aplicación de la tercera dosis -mes 51 para la alternativa y mes 7 para el tradicional- fueron 1.55 para HPV16 (95% IC 1.15-2.08) y 1.53 para HPV18 (95% IC 1.12-2.09). La tasa de seropositividad fue superior a 99% en ambos grupos. Conclusiones: la aplicación de un esquema alternativo de tres dosis (0-6-50 meses) en niñas parece inducir una respuesta inmune no inferior al esquema tradicional un mes después de la última dosis. Se necesitan más estudios para determinar las dosis mínimas e intervalos óptimos para obtener la mejor cobertura para la infección por VPH.
Subject(s)
Humans , Female , Child , Immunization Schedule , Immunization, Secondary/methods , Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18/administration & dosage , Immunogenicity, Vaccine/immunology , Time Factors , Human papillomavirus 16/immunology , Human papillomavirus 18/immunology , Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18/immunology , Mexico , Antibodies, Viral/biosynthesis , Antibodies, Viral/bloodABSTRACT
Objective To understand the influence of HBsAg+ pregnant woman on the persistence of hepatitis B surface antibody(HBsAb)of neonates in three years after the first"0,1,6"immunization,and the influences of regular examination every half-year and revaceination in time on maintaining the immune effect. Methods Twenty neonates born from HBsAg-mothers and 24 from HBsAg+ mothers were followed up for 3 years.And children whose HBsAb's titer faded or disappeared(unstable)received recombinate yeast-derived hepatitis B gene vaccine.The proportion of children with unstable HBsAb and the positive rate of HBsAb on 7 month-old and 3 year-old were compared. Results The unstable rate of HBsAb in HBsAg- and HBsAg+ groups were 20.0%(4/20)and 79.2%(19/24),respectively(P<0.05).The rate of revaccination in these two groups were significantly different.The positive rate of HBsAb in 7 month-old children of HBsAg-mothers was 100.0%(20/20)and 62.5%(15/24)in those of the HBsAg+ group(P<0.05).No statistically difference was detected between the two groups when followed up at 3 years of age[85.0%(17/20)vs 91.7%(22/24),P>0.05]. Conclusions HBsAg+ mothers would reduce the stability of HBsAb in their neonates within three years after the first"0,1,6"immunization,but the immune effect of vaccination against hepatitis B can be maintained through regular examination every half or one year and revaccination.
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Objective To study effect of nasal tolerance with rat-derived 97-116 peptide of AChR α-subunit(Rα97-116(V108A))on the manifestation of muscle weakness and the immunity function of experimental autoimmune myasthenia gravis(EAMG).Methods Twenty-two EAMG model Lewis rats immunized thrice with Rα97-116(V108A)were divided randomly into tolerance group and control group.They were respectively immunized with Rα97-116(V108A)and PBS buffer solution for 10 days via nasal mucous.Then the body weight and Lennon score of two group Lewis rats were measured.Their serum anti-AChR antibodies were tested by ELISA,the expression levels of CD28,CTLA4,B7-1 and B7-2 were determined by flow cytometry.Results Compared with control group at different time points.the body weight of tolerance group rats(tolerance group(228.1±5.8)g,control group(215.0±16.2)g,t=2.395,P＜0.05)increased,the mean clinical score of rats(tolerance group 1.55±0.44.control group 2.10±0.66,t=-2.20,P＜0.05)decreased and the amount of serum anti-AChR antibody(tolerance group 0.97±0.20,control group 1.27±0.26,t=-2.857,P＜0.05)decreased obviously.the amount of CD28,B7-1,B7-2,CTLA4(%)expressed on the surface of peripheral blood cells(tolerance group:27.35±7.05,4.73±0.58,2.71±0.35,1.72±0.44,control group:40.02±8.81,9.52±1.25,5.88±1.09,2.64±0.47)down-regulated markedly(t=3.479,10.861,8.755,4.403,all P＜0.01).Conclusion Nasal mucous tolerance with Rα97-116(V108A)could ameliorate muscular weakness of EAMG rats while activates T cell and inhibits B cellular immunity.