[Immunogenicity and safety of the influenza vaccine, in a population older than 55-years in Mexico]. / Inmunogenicidad y tolerancia de una vacuna contra influenza, en una población mexicana mayor de 55 años de edad.

OBJECTIVE: To confirm the immunogenicity and tolerance of the inactivated, fractionated, and purified influenza vaccine, in a Mexican adult population aged 55 and older, medically served at a Petróleos Mexicanos Hospital (Pemex, Mexican Oil Company). MATERIAL AND METHODS: The study was conducted between November and December, 2000, among ninety adult subjects aged 55 years and older who were seen at the Hospital Central Sur Pemex. The primary endpoints regarding immunogenicity were the percentage of individuals with protective antibodies targeting hemagglutinins higher than or equal to 1:40, and the percentage of subjects who seroconverted as measured by a four-fold increase in protective antibody production. Secondary endpoints included the frequency of local and systemic reactions to the vaccine. An additional criterion that was evaluated included antigen-antibody affinity assays to measure the polyclonal antibody response to the vaccine and the specific generation of high-affinity antibodies to viral proteins, before and after vaccination. RESULTS: The antibody protection rate was 95.6% against the HINI strain, 98.9% against the H3N2 strain, and a 100% against the B/Yamanashi strain. Seroconversion to the HINI strain was elicited in 74.4% of subjects, to the H3N2 strain in 88.9%, and to the B/Yamanashi strain in 82.2%. Eighteen (20%) subjects developed local reactions; 17 (18.8%) developed a systemic reaction post vaccination at day 5 and nine subjects (10%) at day 28. Local reactions consisted of pain in 10 (11.1%) subjects, redness in 8 (8.8%), and induration in 6 (6.6%). General malaise, headache, and fever were identified in 10, 8.8, and 0% of subjects, respectively, at day 5, and in 4.4, 6.6, and 0%, respectively, at day 28. CONCLUSIONS: Influenza vaccine was highly immunogenic in a healthy Mexican adult population aged 55 years and older. The generation of high-affinity antibodies to the virus after vaccination was also demonstrated. Local and systemic adverse reactions to the vaccine identified in our study were similar to those in previous reports. The results of this study can be extrapolated to other health institutions serving this adult population to increase influenza vaccine coverage rates.

Inmunogenicidad y tolerancia de una vacuna contra influenza, en una población mexicana mayor de 55 años de edad / Immunogenicity and safety of the influenza vaccine, in a population older than 55-years in Mexico

OBJETIVO: Verificar la inmunogenicidad y tolerancia de una vacuna purificada, inactivada y fraccionada contra influenza, en adultos mexicanos derechohabientes de Petróleos Mexicanos (Pemex). MATERIAL Y MÉTODOS: Se incluyeron 90 adultos mayores de 55 años de edad, derechohabientes de los servicios médicos del Hospital Central Sur Pemex, durante los meses de noviembre y diciembre de 2000. Los criterios evaluados en relación con la inmunogenicidad incluyeron el porcentaje de sujetos protegidos, cuantificados por medio de anticuerpos antihemaglutininas superior o igual a 1:40, así como por el porcentaje de seroconversión determinado por el título inicial de anticuerpos multiplicado por un factor 4X. Los criterios secundarios fueron la frecuencia de reacciones adversas tanto locales como sistémicas. Se realizaron estudios de afinidad antígeno-anticuerpo para determinar la respuesta policlonal de anticuerpos y de anticuerpos de alta afinidad prevacunación y posvacunación. Se calcularon frecuencias y porcentajes. RESULTADOS: Se identificó una seroprotección en 95.6 por ciento de los sujetos a la cepa H1N1, de 98.9 por ciento a la cepa H3N2 y de 100 por ciento a la cepa B/ Yamanashi. En cuanto a los porcentajes de seroconversión, se identificó un incremento 4X de 74.4 para la cepa H1N1, de 88.9 para la cepa H3N2, y de 82.2 para la cepa B / Yamanashi. Un total de 18 individuos (20 por ciento) presentaron reacciones locales, mientras que 17 (18.8 por ciento) presentaron reacciones sistémicas a los cinco días posvacunación y nueve sujetos (10 por ciento) a los 28 días. Las reacciones locales a los cinco días consistieron en dolor, en 10 individuos (11.1 por ciento); enrojecimiento, en ocho (8.8 por ciento), e induración, en seis (6.6 por ciento). Malestar general, cefalea y fiebre se presentaron a los cinco días en 10, 8.8, y 0 por ciento de individuos, respectivamente, y en 4.4, 6.6, y 0 por ciento, respectivamente, a los 28 días. CONCLUSIONES: Esta vacuna contra influenza demostró ser altamente inmunogénica en adultos mexicanos mayores de 55 años de edad. Se demostró también la producción de anticuerpos de alta afinidad contra el virus, posterior a la vacunación. Además, se identificó una frecuencia de reacciones locales y sistémicas similares a las previamente reportadas...

[Reactogenicity of the simultaneous administration of influenza and pneumococcal vaccines in adults over 55 years of age]. / Reactogenicidad de la administración simultánea de las vacunas contra influenza y neumococo en adultos mayores de 55 años de edad.

BACKGROUND: Pneumonia is the principal cause of morbidity and mortality in PEMEX medical services. Vaccination against influenza is 72% effective in preventing hospitalizations and 87% effective in preventing deaths related to this virus, and vaccination against pneumococcus is 60% effective in preventing invasive diseases by this microorganism. ACIP recommends use of both vaccines simultaneously in adults over 65 years of age. OBJECTIVES: To describe the frequency, duration and severity of local and systemic reactions related to the simultaneous administration of vaccines against influenza and pneumococcus in adults over 55 years of age, and compare with reactions related to influenza vaccine. MATERIAL AND METHODS: Two hundred-thirty two adults over 55 years of age were randomly assigned to two groups, group A (114 subjects) received influenza vaccine, group B (118 subjects) received influenza and pneumococcus vaccines simultaneously. RESULTS: Comparing the number of subjects with local reactions on the right arm between groups A and B (17 subjects vs. 27 subjects), differences were not statistically significative (p = 0.121). Systemic reactions were not statistically significative either (p = 0.126) when results were compared between both groups (30 from group A vs. 42 for group B). CONCLUSIONS: Simultaneous administration of influenza and pneumococcus vaccines has proven to be safety. In the absence of contraindications, there is no reason for not offering both vaccines in the same medical visit.

Reactogenicidad de la administración simultánea de las vacunas contra influenza y neumococo en adultos mayores de 55 años de edad / Reactogenicity of the simultaneous administration of influenza and pneumococcal vaccines in adults over 55 years of age

Background. Pneumonia is the principal cause of morbidity and mortality in PEMEX medical services. Vaccination against influenza is 72% effective in preventing hospitalizations and 87% effective in preventing deaths related to this virus, and vaccination against pneumococcus is 60% effective in preventing invasive diseases by this microorganism. ACIP recommends use of both vaccines simultaneously in adults over 65 years of age. Objectives. To describe the frequency, duration and severity of local and systemic reactions related to the simultaneous administration of vaccines against influenza and pneumococcus in adults over 55 years of age, and compare with reactions related to influenza vaccine. Material and methods. Two hundred-thirty two adults over 55 years of age were randomly assigned to two groups, group A (114 subjects) received influenza vaccine, group B (118 subjects) received influenza and pneumococcus vaccines simultaneously. Results. Comparing the number of subjects with local reactions on the right arm between groups A and B (17 subjects vs. 27 subjects), differences were not statistically significative (p = 0.121). Systemic reactions were not statistically significative either (p = 0.126) when results were compared between both groups (30 from group A vs. 42 for group B). Conclusions. Simultaneous administration of influenza and pneumococcus vaccines has proven to be safety. In the absence of contraindications, there is no reason for not offering both vaccines in the same medical visit.

Antecedentes. La neumonía es la principal causa de morbilidad y mortalidad en adultos mayores en los servicios mèdicos de PEMEX. La vacunación contra influenza ha probado ser efectiva en prevenir 72% de las hospitalizaciones y 87% de las muertes causadas por este virus y la vacunación contra neumococo ha sido efectiva en prevenir 60% de las enfermedades invasoras por este microorganismo. El ACIP recomienda que ambas vacunas se administren en forma simultánea a los adultos mayores de 65 años de edad. Objetivos. Describir la frecuencia, duración y severidad de las reacciones locales y sistèmicas asociadas a la administración simultánea de las vacunas contra influenza y neumococo en adultos mayores de 55 años de edad, y comparar los resultados con las reacciones asociadas al uso de vacuna contra influenza únicamente. Material y mètodos. Se asignaron en forma aleatoria 232 adultos mayores de 55 años de edad a dos grupos, el grupo A (114 sujetos) recibieron la vacuna contra influenza y el grupo B (118 sujetos) recibieron las vacunas contra influenza y neumococo en forma simultánea. Resultados. Al comparar el número de individuos con reacciones locales en el brazo derecho entre el grupo A y el grupo B (17 sujetos vs. 27 sujetos) las diferencias no fueron estadísticamente significativas (p = 0.121). En cuanto a las reacciones sistèmicas, èstas tampoco fueron estadísticamente significativas (p = 0.126) cuando se compararon los sujetos en ambos grupos (30 del grupo A vs. 42 del grupo B). Conclusiones. La administración simultánea de las vacunas contra influenza y neumococo ha probado ser segura. En ausencia de contraindicaciones, no hay razón para no ofrecer estas dos vacunas en la misma visita mèdica.