Declaración SLIPE: Aumento de la cobertura antipoliomielítica con vacunas más seguras: una urgencia inaplazable en Latinoamérica

Ante el riesgo real de ocurrencia de brotes de parálisis fláccida aguda en la región debidos a poliovirus derivado de la vacuna Sabin o a la importación de poliovirus salvaje, la Sociedad Latinoamericana de Infectología Pediátrica comisionó a un grupo ad hoc de expertos integrantes del Comité de Vacunas y Biológicos de la institución, para redactar un documento oficial de posición sobre la necesidad imperiosa de incrementar los niveles de inmunización contra la enfermedad en la región e incorporar definitivamente en forma exclusiva la vacuna de polio inactivada en todos los esquemas nacionales de vacunación. La presente publicación discute las principales conclusiones y recomendaciones generadas como resultado de esta actividad.

Given the actual risk of poliomyelitis outbreaks in the region due to poliovirus derived from the Sabin vaccine or the importation of wild poliovirus, the Latin American Society of Pediatric Infectious Diseases commissioned an ad hoc group of experts from the institution's Vaccines and Biologicals Committee, to draft an official position paper on the urgent need to increase immunization levels against the disease in the region and incorporate inactivated polio vaccine exclusive schedules in all national immunization programs. This publication discusses the main conclusions and recommendations generated as a result of such activity.

Increasing polio coverage with safer vaccines: a pressing need in Latin America

Given the actual risk of poliomyelitis outbreaks in the region due to poliovirus derived from the Sabin vaccine or the importation of wild poliovirus, the Latin American Society of Pediatric Infectious Diseases commissioned an ad hoc group of experts from the institution's Vaccines and Biologicals Committee, to draft an official position paper on the urgent need to increase immunization levels against the disease in the region and incorporate inactivated polio vaccine exclusive schedules in all national immunization programs. This publication discusses the main conclusions and recommendations generated as a result of such activity.

Ante el riesgo real de ocurrencia de brotes de parálisis fláccida aguda en la región debidos a poliovirus derivado de la vacuna Sabin o a la importación de poliovirus salvaje, la Sociedad Latinoamericana de Infectología Pediátrica comisionó a un grupo ad hoc de expertos integrantes del Comité de Vacunas y Biológicos de la institución, para redactar un documento oficial de posición sobre la necesidad imperiosa de incrementar los niveles de inmunización contra la enfermedad en la región e incorporar definitivamente en forma exclusiva la vacuna de polio inactivada en todos los esquemas nacionales de vacunación. La presente publicación discute las principales conclusiones y recomendaciones generadas como resultado de esta actividad.

Effect of Simultaneous Administration of Oral Polio Vaccine on Local Reaction of BCG Vaccine in Term Infants.

Objective: To study local reaction and to ascertain timing of scar formation in infants after BCG vaccination at birth, with and without simultaneous administration of trivalent OPV. Design: Prospective observational study. Setting: Teaching hospital in Lucknow, India. Participants: 152 term neonates born in the hospital and given BCG and OPV 0-dose simultaneously before discharge, within 7 days of birth (Group I) , and 122 infants born at home or in private health facility, not given OPV-0 dose, coming for vaccination within 7 days of age (Group 2). Intervention/Observation: Follow up done at 6 week, 10 week, 14 week and 9 months. Local reaction was recorded at the site of BCG vaccination. Results: Scar formed in ≤14 wks in 51.3% and 89.3% babies in Group 1 and Group 2, respectively following BCG vaccination (P<0.001). At 9 months, scar developed in 93.9% infants in Group I and 94.3% babies in Group II. Abortive reaction and nonreactors were similar in both groups (P>0.05). Conclusions: Simultaneous administration of BCG vaccine with trivalent OPV to term infants in early neonatal period prolongs the time of scar formation but sequence of local reaction is not affected.

Prevalence of prolonged and chronic poliovirus excretion among persons with primary immune deficiency disorders in the Philippines

OBJECTIVES: As part of the global initiative to eradicate poliovirus infections this study aims to: (1) estimate the prevalence of vaccine-derived poliovirus excretion among persons diagnosed with primary immune (B-cell or combined B/T-cell) deficiency disorders (PIDD) in the Philippines; (2) describe clinical features of these PIDD patients excreting poliovirus; (3) genetically characterize vaccine-derived polioviruses isolated from persons with PIDDs; and (4) determine the duration of poliovirus excretion among subjects who tested positive for vaccine-derived poliovirus excretion. METHODS: Seventy-one (71) Filipino patients (ages 0-35 years of age) with PIDD were recruited retrospectively and prospectively over a period of 16 months. The study participants, after informed consent and administration of a questionnaire for baseline data, underwent further testing of quantitative immunoglobulin levels (IgG, IgA, and IgM) and stool poliovirus isolation using two stool samples. Stool specimens which tested positive for the poliovirus were sent to the Regional Reference Laboratory in Australia for further characterization by Intratypic Differentiation (ITD) and Vaccine-derived polioviruses (VDPV) real-time PCR. These participants were then monitored on a monthly basis until laboratory tests identified two sequential months of negative poliovirus stool specimens. RESULTS: Seventy-one (71) patients underwent interview and quantitative serum immunoglobulin testing. However, one patient expired prior to stool isolate collection. This study, then, documented that none of the remaining 70 Filipino individuals (0-35 years old) with confirmed or suspected PIDDs chronically excreted immunodeficiency-associated vaccine-derived poliovirus (IVDPV). One patient who was a recent OPV-recipient excreted poliovirus Sabin-like 1 transiently (less than 1 month) and two patients excreted non polio-enteroviruses. CONCLUSIONS: Chronic and prolonged poliovirus excretion appears to be uncommon among Filipino patients with diagnosed Primary Immunodeficiency Disease Disorders. However, as part of the continuing global initiative for poliovirus eradication, vigilance is still necessary in patients with primary immunodeficiency diseases. Adequate identification of these patients followed by monitoring their capacity for viral excretion and environmental contamination may be necessary to achieve this goal.

Timing of Zero dose of OPV, first dose of hepatitis B and BCG vaccines.

The Indian Academy of Pediatrics has been recommending Hepatitis B vaccination for infants since 1992. This community based cross sectional study carried out in the rural and urban areas of Tamil Nadu found no significant rural urban difference in the proportions of children who had received BCG in 3 days/7 days and OPV-zero dose in 3 days/7 days after birth. The proportion of children who had received first dose of Hepatitis B in 3 days was significantly lower than those who had received BCG and OPV within 3 days after birth. The proportion of children who had received Hepatitis B on the day of birth was significantly lower in the rural area than in the urban area.

Eradicating Polio: It's Feasibility in Near Future.

Continuous wild poliovirus transmission despite 12 years of intensive surveillance has raised serious questions about the feasibility of polio eradication programme with current strategy in near future. At present most of the cases are confined to four endemic countries, which are causing sporadic outbreaks in non-endemic areas. India has experienced a significant increase in number of cases reported in 2006 compared to previous year. Outbreaks originated in western UP which was due to the accumulation of susceptibles between the last outbreak in 2002 and early 2006. Substantial improvement has been observed in strategies of polio eradication but still there are gaps in the programme implementation which needs immediate attention so that goal of polio eradication can be achieved at the earliest opportunity. Even though there are many issues but there are also many factors, which favour polio eradication. These factors include new tool in form of m OPV, natural immunity due to recent outbreak, limiting international spread of polio, new researches to guide programme in right direction, political commitments from endemic countries, etc. 2008 presents the best opportunity ever to interrupt wild polio virus transmission which will lead to global eradication of Polio. Since global eradication is within sight, it is scientifically possible to eradicate the disease in near future.

Prospective Analysis on Strategy of OPV Switching to Sabin-IPV at the Endgame of Poliomyelitis Eradication in China / 中国疫苗和免疫

Objective To explore the immunization strategy at the endgame of poliomyelitis eradication in China.Methods To search the related study databases by the mean of evidence based medicine,and to investigate the update status of production and usage of polio vaccine in China.The general prospective analysis was conducted on aspects of the comparison of different immunization strategies,the feasibility of oral poliovirus vaccine(OPV)switching to Sabin strain inactivated poliovirus vaccine(Sabin-IPV)and the Sabin-IPV immunization schedule.Results The immunization strategy of OPV switching to IPV should be considered to choose in China because the domestic Sabin-IPV products will be registered soon and the switching feasibility is already provided with the conditions of police,technique,vaccine supply,and other guarantee.The routine immunization of Sabin-IPV can be carried out referring to the update OPV immunization schedule.Conclusion The study on immunization strategy at the endgame of poliomyelitis eradication should be further enhanced and the preparation of OPV switching Sabin-IPV should be considered in China.

Seroprevalencia de anticuerpos contra el poliovirus 1 en niños mexicanos / Seroprevalence of antibodies against poliovirus type 1 in Mexican children

OBJETIVO: Analizar la frecuencia y distribución de la prevalencia de anticuerpos contra el virus de la poliomielitis tipo 1 en niños menores de 10 años en México, además de contribuir a la evaluación del programa de vacunación. MATERIAL Y MÉTODOS: Se estudió la presencia de anticuerpos contra el poliovirus tipo 1 en una muestra de la Encuesta Nacional de Salud 2000. Los sueros se recolectaron entre noviembre de 1999 y junio de 2000 a nivel nacional. La muestra constó de 6 270 niños de uno a nueve años de edad y se utilizó la técnica de neutralización. RESULTADOS: La seropositividad fue de 99.3 por ciento (IC95 por ciento99.1-99.7). Se identificaron como factores de riesgo de susceptibilidad el analfabetismo (RM= 1.5, p= 0.002) y el bajo ingreso familiar (RM= 1.4, p= 0.0487) y como factor protector el acceso a la seguridad social (RM= 0.41, p=0.04). CONCLUSIONES: Las actividades del programa de vacunación que han llevado a cabo las instituciones de salud han dado resultados en el control y eliminación de la enfermedad. Sin embargo, los programas de vacunación no deben interrumpirse, incluso si se ha registrado 99.3 por ciento de seropositividad; no puede soslayarse que al convertir el 0.7 por ciento restante, se calcula que hay 190 000 niños susceptibles de contraer la enfermedad. Estos niños se localizan sobre todo en el sur del país.

OBJECTIVE: To analyze the frequency and distribution of the prevalence of antibodies against the poliomyelitis type 1 virus in children 1-9 years old in Mexico. MATERIAL AND METHODS: Antibodies against poliovirus type 1 (neutralization method) were studied in 6 270 sera selected from the 24 232 sera from children one to nine years old, collected by the 2000 National Health Survey (ENSA 2000) that was conducted from November 1999 to June 2000. RESULTS: Overall seroprevalence was 99.3 percent (95 percentCI: 99.1-99.7). Using bivariate analysis, absence of antibodies was shown to be associated with illiteracy (OR= 1.5, p=0.002) and low household income (OR= 1.4, p=0.0487), while those children having access to social security (OR= 0.41 p=0.04) had a higher likelihood of having protective antibodies. CONCLUSIONS: The vaccination program activities conducted by health institutions have been successful in the control and eradication of the disease. However, a note of caution is necessary since the expansion of data reveals that although seroprevalence of antibodies has an upper limit of 99.3 percent, 0.7 percent of children (roughly 190 000) are susceptible to developing the disease. Most of these children live in the southern regions of the country.

The sterility of OPV produced by Poliovac from 1994 to 2003

A study was conducted to test the sterility of 416 final lots of OPV produced by POLIOVAC, Vietnam from 1994 to 2003 in thioglycolate and soybean casein digest media under the standard operating procedure. The study results showed that all the tested lots (461/461 = 100%) had met the requirements for sterility