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Stanley Plotkin

Publications and source records attributed to Stanley Plotkin.

12 recordsLinked to original sources
PubMed2006

Analysis of reversions in the 5'-untranslated region of attenuated poliovirus after sequential administration of inactivated and oral poliovirus vaccines.

Replication of Sabin strains used in oral poliovirus vaccine (OPV) in the intestines of vaccine recipients leads to reversions that increase virus neurovirulence. Previously, a small study reported that prior immunization with inactivated poliovirus vaccine (IPV) resulted in faster accumulation of revertant virus, thus potentially increasing the risk of vaccine-associated paralytic poliomyelitis. We studied the impact that prior immunization with IPV and OPV has on shedding of revertant virus by healthy infants. By polymerase chain reaction (PCR), we amplified full-length poliovirus genomes directly from stool specimens from unimmunized infants and from infants previously immunized with IPV or OPV. The amplicons were used to quantify reversions in the 5'-untranslated region, using oligonucleotide microarray hybridization. Nearly all 140 samples that were PCR positive contained varying amounts of revertants of all 3 poliovirus serotypes. Polioviruses of Sabin types 2 and 3 reverted more easily than those of type 1. Prior vaccination with IPV did not increase the proportion of revertants after OPV administration.

DNA, Viral↗
PubMed2005

Effect of different vaccination schedules on excretion of oral poliovirus vaccine strains.

Inactivated poliovirus vaccine (IPV) is believed to induce significantly lower mucosal immunity than oral poliovirus vaccine (OPV). Most of the data supporting this were generated before enhanced IPV (eIPV) was introduced. Excretion of poliovirus by OPV recipients can be used to assess intestinal immunity. We studied polymerase chain reaction amplification of viral complementary DNA from the stool of children vaccinated with either OPV alone or eIPV. Of first-time OPV recipients, 92% excreted virus after 1 week, and 81% excreted virus after 3 weeks. Prior vaccination with OPV reduced the number to 22% and shortened the duration of virus excretion (to 5% after 3 weeks). Two doses of IPV reduced the number of poliovirus-positive 1-week samples (to 76%), the duration of shedding (to 37% at 3 weeks), and the quantity of excreted virus. This suggests that IPV-vaccinated communities are partially protected from the spread of poliovirus. Further enhancement of IPV potency may lead to even higher levels of mucosal immunity.

DNA, Complementary↗
PubMed2005

The global pertussis initiative: process overview.

In 2001, the Global Pertussis Initiative was established as a scientific forum to analyze the status of pertussis globally and to evaluate various immunization strategies to improve disease control. Thirty-seven multidisciplinary experts from 17 countries participated. The initiative was conducted in 3 stages: assessment of the international epidemiology, diagnosis, health and economic burden, and prevention and treatment of pertussis; evaluation and prioritization of 7 immunization strategies to address the problems; and identification of solutions to surmount potential barriers to the implementation of these strategies. A health-economic model, created for the Initiative, analyzed the cost-effectiveness of the selected immunization strategies. Discussion, debate, and consensus were facilitated via a roundtable meeting, teleconferences and use of a closed, interactive website, allowing the participants to share data, knowledge, experience, and opinion. This article describes the processes undertaken to conduct the Initiative.

Communicable Disease Control↗
PubMed2005

Potential strategies to reduce the burden of pertussis.

Pertussis continues to be a significant cause of morbidity and mortality among nonimmunized young infants. Although the inception of childhood pertussis immunization programs has significantly reduced the occurrence of the disease in children, waning vaccine-induced immunity permits the disease to affect adolescents and adults, who in turn transmit the disease to unimmunized or incompletely immunized infants. The Global Pertussis Initiative brought together experts from 17 countries around the world to evaluate strategies to improve disease control. Seven strategies were considered: (1) universal adult immunization; (2) selective immunization of mothers and close family contacts of newborns; (3) selective immunization of health care workers; (4) selective immunization of child care workers; (5) universal immunization of adolescents; (6) preschool booster at 4-6 years of age; and (7) reinforcement and/or improvement of current infant and toddler immunization strategies. Because immunization programs vary widely from country to country, no single strategy is likely to be appropriate for all. Moreover it would be helpful to have additional data to support the strategies and provide a better understanding of the disease so that new approaches can be monitored effectively. However, certain steps can be taken now to reduce the incidence of pertussis.

Adolescent↗
PubMed2004

New pertussis vaccination strategies beyond infancy: recommendations by the global pertussis initiative.

BACKGROUND: The Global Pertussis Initiative, an expert scientific forum, was established to address the ongoing problems associated with pertussis disease worldwide. METHODS: The group analyzed pertussis disease trends, developed recommendations to improve disease control through expanded vaccination strategies, and proposed solutions to barriers to implementation and support of research activities. RESULTS: Bordetella pertussis infection is endemic and continues to be a serious problem among unvaccinated or incompletely vaccinated infants. In addition, the reported incidence of pertussis disease is increasing in adolescents and adults, who not only experience a considerable health burden themselves but also infect vulnerable infants. CONCLUSIONS: Current vaccination strategies need to be reinforced. Expanded vaccination should include adding booster doses to existing childhood schedules (preschool or adolescent) and booster doses for those specific adult subgroups that have the highest risk of transmitting B. pertussis infection to infants (i.e., new parents, other contacts of newborns, and health care workers). More epidemiological studies and studies of disease transmission and the cost-effectiveness of vaccination would be valuable, and surveillance, diagnostic improvements, and educational campaigns are needed for implementation. However, as a prelude to universal adult vaccination, immediate universal adolescent vaccination should be instituted in countries in which it is economically feasible.

Adolescent↗
PubMed2004

Vaccine development to prevent cytomegalovirus disease: report from the National Vaccine Advisory Committee.

Cytomegalovirus (CMV) infection is the most common intrauterine infection in the United States, and it exacts a heavy toll when it infects children and immunocompromised individuals. A CMV vaccine was assigned the highest priority by the Institute of Medicine in its 1999 assessment of targets for vaccine development. The priority was based on the cost and human suffering that would be alleviated by reducing the disease burden of congenital CMV infection. The National Vaccine Advisory Committee and invited experts examined the prospects for a CMV vaccine and the actions needed to bring about successful vaccine development at a National Vaccine Program Office workshop in October 2000. This article summarizes information about the changing epidemiology of CMV and immune responses to infection and immunity, and it reviews the current status of several vaccine candidates. Support of government agencies for CMV vaccine research and development is critical to address this need.

Adult↗
PubMed2004

Poxvirus-based vaccine candidates for HIV: two decades of experience with special emphasis on canarypox vectors.

Poxvirus vectors have emerged as important vectors for licensed veterinary vaccines and candidate vaccines for humans. Vaccinia, highly-attenuated vaccinia strains and avipoxviruses have been assessed extensively in preclinical models, as well as in humans, to determine their immunogenicity and protective efficacy against HIV. The attenuated vaccinia strains and avipoxviruses have been shown to be safe and able to carry HIV genes and express their proteins to induce both antibodies and cellular immune responses. Preclinical studies show protection against HIV challenge. When using a live attenuated vector system, one must be cognizant of the potential for immune dampening because of vector-specific immunity. In this regard, avipoxviruses, such as canarypox, appear free of the inhibitory effects of vector immunity and repeated use. Unlike vaccinia-based vectors derived from classical vaccine strains, NYVAC and modified vaccinia Ankara may be less susceptible to this effect. In the coming 5 to 10 years, we will certainly know whether this class of vaccine candidates, either alone or in a prime-boost format with other vectors or proteins, will contribute to HIV disease management either from a preventive or therapeutic perspective. Additional Phase I and II studies, as well as human efficacy trials will provide new information. Furthermore, it is hoped that this body of data will contribute to a better understanding of the relevance of specific immunogenicity end points to protection and the predictive value of available animal models in HIV vaccine development.

AIDS Vaccines↗
PubMed2003

Virus-inhibiting surgical glove to reduce the risk of infection by enveloped viruses.

Needle puncture and other accidents that occur during surgery and other procedures may lead to viral infections of medical personnel, notably by hepatitis C (HCV) and human immunodeficiency virus (HIV), now that hepatitis B can be prevented by vaccination. A new surgical glove called G-VIR, which contains a disinfecting agent for enveloped viruses, has been developed. Herpes simplex type 1 (HSV) was used as a standard enveloped virus in both in vitro and in vivo tests of the virucidal capacity of the glove. Bovine viral diarrhea virus (BVDV) and feline immunodeficiency virus (FIV) were used as models for HCV and HIV, respectively. For in vitro study, a contaminated needle was passed through a glove and residual virus was titrated; for in vivo studies, animals were stuck with a contaminated needle through a glove. Despite variation in virus enumeration inherent in the puncture technique, statistical evaluation showed that infection was reproducibly and substantially reduced by passage through the virucidal layer. For BVDV, the amount of virus passing through the virucidal glove was reduced in 82% of pairwise comparisons with control gloves that lacked the virucidal agent; when plaque counts were adjusted to a common dilution, the median count for the virucidal glove was on the average reduced >10-fold. In experiments in which the proportion of wells infected with FIV was measured, the ratio of TCID(50) values (control glove to G-VIR) was >15, and probably much higher. For HSV, the amount of virus passing through the virucidal glove was reduced in 81% of comparisons with control gloves; the median of adjusted plaque counts was reduced on the average approximately eightfold or ninefold. In vivo tests with FIV and HSV in cats and mice, respectively, found smaller percentage reductions in infection than the in vitro tests but confirmed the virucidal effect of the gloves.

Animals↗
PubMed2002

Effect of previous or simultaneous immunization with canarypox expressing cytomegalovirus (CMV) glycoprotein B (gB) on response to subunit gB vaccine plus MF59 in healthy CMV-seronegative adults.

Development of a vaccine for prevention of congenital cytomegalovirus (CMV) disease is a priority. This study evaluated a "prime-boost" strategy by comparing the safety and immunogenicity of 3 doses of subunit CMV glycoprotein B (gB) vaccine plus MF59 (a squalene-in-water emulsion), 2 doses of a canarypox recombinant vaccine expressing CMVgB (ALVAC-CMVgB) followed by 2 doses of the subunit gB vaccine, 3 doses of both vaccines administered concomitantly, and placebo in 105 healthy, CMV-seronegative adults. Systemic adverse events were rare, but local reactions were common in all groups. After the first subunit vaccination, neutralizing antibody titers in the prime-boost group were comparable to those in subjects receiving 2 subunit vaccinations, indicating a priming effect of ALVAC-CMVgB. However, after the final dose, antibody and cell-mediated immune responses were not significantly different among the groups. All 3 vaccine regimens induced high-titer antibody and lymphoproliferative responses, but no benefit for priming or simultaneous vaccination was detected.

Adjuvants, Immunologic↗