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R W Sutter

Publications and source records attributed to R W Sutter.

At least 37 records · Page 2Linked to original sources
PubMed2000

Disease eradication as a public health strategy: a case study of poliomyelitis eradication.

Disease eradication as a public health strategy was discussed at international meetings in 1997 and 1998. In this article, the ongoing poliomyelitis eradication initiative is examined using the criteria for evaluating candidate diseases for eradication proposed at these meetings, which covered costs and benefits, biological determinants of eradicability (technical feasibility) and societal and political considerations (operational feasibility). The benefits of poliomyelitis eradication are shown to include a substantial investment in health services delivery, the elimination of a major cause of disability, and far-reaching intangible effects, such as establishment of a "culture of prevention". The costs are found to be financial and finite, despite some disturbances to the delivery of other health services. The "technical" feasibility of poliomyelitis eradication is seen in the absence of a non-human reservoir and the presence of both an effective intervention and delivery strategy (oral poliovirus vaccine and national immunization days) and a sensitive and specific diagnostic tool (viral culture of specimens from acute flaccid paralysis cases). The certification of poliomyelitis eradication in the Americas in 1994 and interruption of endemic transmission in the Western Pacific since March 1997 confirm the operational feasibility of this goal. When the humanitarian, economic and consequent benefits of this initiative are measured against the costs, a strong argument is made for eradication as a valuable disease control strategy.

Developed Countries↗
PubMed2000

Stopping poliovirus vaccination after eradication: issues and challenges.

Since 1988 reported polio cases worldwide have declined by about 85% and the number of known or suspected polioendemic countries has decreased from over 120 to less than 50. With eradication of poliomyelitis approaching, issues potentially affecting when and how vaccination against poliovirus can be stopped become extremely important. Because of the potential risks and benefits inherent in such a decision, the best available science, a risk-benefit analysis, contingency plans, a stock pile of poliovirus vaccines, and the endorsement by the global policy-making committees will all be needed before vaccination can be discontinued. The scientific basis for stopping polio immunization has been reviewed by WHO. This Round Table article summarizes the current state of knowledge, provides an update on the processes and timelines for certification, containment, and stopping vaccination, and highlights some of the unanswered scientific questions that will be addressed by further research. These include whether transmission of vaccine-derived poliovirus strains could be sustained so that poliomyelitis could re-emerge in a future unvaccinated population and whether prolonged excretion of vaccine-derived poliovirus from individuals with immune deficiencies could be a mechanism through which this could occur.

Biological Warfare↗
PubMed1998

Outbreak of paralytic poliomyelitis in Albania, 1996: high attack rate among adults and apparent interruption of transmission following nationwide mass vaccination.

After >10 years without detection of any cases of wild virus-associated poliomyelitis, a large outbreak of poliomyelitis occurred in Albania in 1996. A total of 138 paralytic cases occurred, of which 16 (12%) were fatal. The outbreak was due to wild poliovirus type 1, isolated from 69 cases. An attack rate of 10 per 100,000 population was observed among adults aged 19-25 years who were born during a time of declining wild poliovirus circulation and had been vaccinated with two doses of monovalent oral poliovirus vaccines (OPVs) that may have been exposed to ambient temperatures for prolonged periods. Control of the epidemic was achieved by two rounds of mass vaccination with trivalent oral poliovirus vaccine targeted to persons aged 0-50 years. This outbreak underscores the ongoing threat of importation of wild poliovirus into European countries, the importance of delivering potent vaccine through an adequate cold chain, and the effectiveness of national OPV mass vaccination campaigns for outbreak control.

Adolescent↗
PubMed1998

Prolonged replication of a type 1 vaccine-derived poliovirus in an immunodeficient patient.

VP1 sequences were determined for poliovirus type 1 isolates obtained over a 189-day period from a poliomyelitis patient with common variable immunodeficiency syndrome (a defect in antibody formation). The isolate from the first sample, taken 11 days after onset of paralysis, contained two poliovirus populations, differing from the Sabin 1 vaccine strain by approximately 10%, differing from diverse type 1 wild polioviruses by 19 to 24%, and differing from each other by 5.5% of nucleotides. Specimens taken after day 11 appeared to contain only one major poliovirus population. Evolution of VP1 sequences at synonymous third-codon positions occurred at an overall rate of approximately 3.4% per year over the 189-day period. Assuming this rate to be constant throughout the period of infection, the infection was calculated to have started approximately 9.3 years earlier. This estimate is about the time (6. 9 years earlier) the patient received his last oral poliovirus vaccine dose, approximately 2 years before the diagnosis of immunodeficiency. These findings may have important implications for the strategy to eliminate poliovirus immunization after global polio eradication.

Adult↗
PubMed1997

Tetanus surveillance--United States, 1991-1994.

PROBLEM/CONDITION: Despite the widespread availability of a safe and effective vaccine against tetanus, 201 cases of the disease were reported during 1991-1994. Of patients with known illness outcome, the case-fatality rate was 25%. REPORTING PERIOD COVERED: 1991-1994. DESCRIPTION OF SYSTEM: Physician-diagnosed cases of tetanus are reported to local and state health departments, the latter of which reports these cases on a weekly basis to CDC's National Notifiable Disease Surveillance System. Since 1965, state health departments also have submitted supplemental clinical and epidemiologic information to CDC's National Immunization Program. RESULTS: During 1991-1994, 201 cases of tetanus were reported from 40 states, for an average annual incidence of 0.02 cases per 100,000 population. Of the 188 patients for whom age was known, 101 (54%) were aged > or = 60 years and 10 (5%) were aged < 20 years. No cases of neonatal tetanus were reported. Among adults, the risk for tetanus increased with age; the risk for persons aged > or = 80 years was more than 10 times greater than the risk for persons aged 20-29 years. All deaths occurred among persons aged > or = 30 years. The case-fatality rate (overall: 25%) increased with age, from 11% in persons aged 30-49 years to 54% in persons aged > or = 80 years. Only 12% of all patients were reported to have received a primary series of tetanus toxoid before onset of illness. For 77% of patients, tetanus occurred after an acute injury was sustained. Of patients who obtained medical care for their injury, only 43% received tetanus toxoid as part of wound prophylaxis. INTERPRETATION: The epidemiology of reported tetanus in the United States during 1991-1994 was similar to that during the 1980s. Tetanus continued to be a severe disease primarily of older adults who were unvaccinated or inadequately vaccinated. Most tetanus cases occurred after an acute injury was sustained, emphasizing the need for appropriate wound management. ACTIONS TAKEN: In addition to decennial booster doses of tetanus-diphtheria toxoid during adult life, the Advisory Committee on Immunization Practices (ACIP) recommends vaccination visits for adolescents at age 11-12 years and for adults at age 50 years to enable health-care providers to review vaccination histories and administer any needed vaccine. Full implementation of the ACIP recommendations should virtually eliminate the remaining tetanus burden in the United States.

Adolescent↗
PubMed1997

Using cost-effectiveness analysis to evaluate targeting strategies: the case of vitamin A supplementation.

Given the demonstrated efficacy of vitamin A supplements in reducing childhood mortality, health officials now have to decide whether it would be efficient to target the supplements to high risk children. Decisions about targeting are complex because they depend on a number of factors; the degree of clustering of preventable deaths, the cost of the intervention, the side-effects of the intervention, the cost of identifying the high risk group, and the accuracy of the 'diagnosis' of risk. A cost-effectiveness analysis was used in the Philippines to examine whether vitamin A supplements should be given universally to all children 6-59 months, targeted broadly to children suffering from mild, moderate, or severe malnutrition, or targeted narrowly to pre-schoolers with moderate and severe malnutrition. The first year average cost of the universal approach was US$67.21 per death averted compared to $144.12 and $257.20 for the broad and narrow targeting approaches respectively. When subjected to sensitivity analysis the conclusion about the most cost-effective strategy was robust to changes in underlying assumptions such as the efficacy of supplements, clustering of deaths, and toxicity. Targeting vitamin A supplements to high risk children is not an efficient use of resources. Based on the results of this cost-effectiveness analysis and a consideration of alternate strategies, it is apparent that vitamin A, like immunization, should be provided to all pre-schoolers in the developing world. Issues about targeting public health interventions can usefully be addressed by cost-effectiveness analysis.

Child, Preschool↗
PubMed1997

Assessment of Guillain-Barré syndrome mortality and morbidity in the United States: implications for acute flaccid paralysis surveillance.

To estimate age-specific incidences and assess the national morbidity and mortality burden for Guillain-Barre syndrome (GBS) in the United States, a national hospital discharge database compiled by the Commission on Professional and Hospital Activities (CPHA) and national death certificate data reported to the National Vital Statistics System were reviewed. During 1985-1991, 10,453 patients with GBS were discharged from CPHA-participating hospitals (estimated annual incidence, 3.0/100,000 population). The age-specific incidence of GBS increased with age from 1.5/100,000 in persons <15 years old to 8.6/100,000 in persons 70-79 years old. The total estimated number of GBS-related deaths from 1985 through 1990 was 3770 (95% confidence interval, 3506-4034), for an average of 628 GBS deaths per year. These rates suggest that the proposed national surveillance system for acute flaccid paralysis should capture at a minimum the 796 GBS cases in persons <15 years old. GBS remains a significant health burden among older adults in the United States, with a marked increase in risk after age 40.

Adolescent↗
PubMed1997

Outbreaks of paralytic poliomyelitis, 1976-1995.

During 1976-1995, 48 outbreaks of paralytic poliomyelitis with a cumulative total of approximately 17,000 cases were reported worldwide. Outbreaks occurred on most continents, affected from 0.1 to 52 persons per 100,000 total population (median, 4.4), lasted 2-25 months (median, 7), typically involved unvaccinated or inadequately vaccinated subgroups within highly immunized communities, and were primarily caused by poliovirus type 1 (74%). Cases in developing countries occurred predominantly among children <2 years of age, while those in industrialized countries tended to occur in older persons who had escaped natural infection earlier in life and who had not been vaccinated or had received poliovirus vaccine of inadequate potency. Partial genomic sequencing studies indicated that at least 15 outbreaks resulted from importation of wild polioviruses, primarily from the Indian subcontinent. These findings illustrate the potential for wide dissemination of wild poliovirus infection and underscore the critical need for maintaining high levels of immunity in all countries and for more aggressive vaccination efforts in areas in which polio is endemic.

Child, Preschool↗
PubMed1997

Sequential use of inactivated poliovirus vaccine followed by oral poliovirus vaccine in Oman.

Seroprevalence and geometric mean titers (GMTs) were compared at 6 and 10 months after vaccination with monovalent type 1 oral poliovirus vaccine (OPV) at 6 months and trivalent OPV at 7 and 9 months. Group 1 had received 4 doses of OPV, group 2 OPV at birth and 3 doses of OPV and inactivated poliovirus vaccine (IPV), and group 3 placebo at birth and 3 doses of IPV. A total of 547 infants completed the study. At 10 months, seroprevalence to poliovirus type 1 was 98%, 99%, and 98% in groups 1, 2, and 3; 100%, 100%, and 98% to poliovirus type 2; and 80%, 96%, and 91% to poliovirus type 3. Differences in seroprevalence among the groups were significant for poliovirus type 3 (P < .001). Between 6 and 10 months, significant increases in seroprevalence and GMTs occurred for poliovirus type 1 but not for types 2 and 3. Two OPV doses following 3 IPV doses did not significantly increase seroprevalence or raise GMTs for poliovirus types 2 and 3; however, significant increases were found for poliovirus type 1, which may have benefitted from monovalent type 1 administration.

Antibodies, Viral↗
PubMed1997

Poliomyelitis in Angola: current status and implications for poliovirus eradication in Southern Africa.

As part of emergency assistance to the Ministry of Health (MOH), national surveillance data for poliomyelitis and charts of cases at the national rehabilitation hospital were reviewed. Poliomyelitis patients admitted to Angola's main pediatric hospital were examined. A mean of 86 cases of poliomyelitis/year were reported in Angola during 1989-1994. Review of records from non-MOH sources uncovered another 74 cases, primarily from areas outside governmental control. Hospital chart reviews revealed that 80% of the cases were children <3 years of age, mainly unvaccinated. Molecular analyses of isolates from cases in Luanda and at the Angola-Namibia border suggest that these isolates are closely related and that > or = 2 strains of wild poliovirus type 1 are circulating currently in Angola. This investigation confirms that poliomyelitis has remained endemic in Angola since independence in 1975. It affects primarily young and unvaccinated children. Control of poliomyelitis in Angola is essential to expand the polio-free zone in southern Africa.

Africa, Southern↗
PubMed1997

Sequential and combined use of inactivated and oral poliovirus vaccines: Dolj District, Romania, 1992-1994.

To determine the feasibility of a vaccination strategy that would reduce the risk of vaccine-associated paralysis while retaining a barrier against the spread of wild poliovirus, a 2-year project was undertaken using enhanced-potency inactivated poliovirus vaccine (IPV) administered at 2 and 3 months of age followed by doses of both IPV and oral poliovirus vaccine (OPV) administered at 4 and 9 months of age. Vaccination coverage by 12 months of age with three or more doses of IPV and two doses of OPV among 16,566 infants eligible for vaccination was > 95% and > 80%, respectively. Among 51 children from whom blood samples were obtained 45 days after their third dose of IPV and first dose of OPV, 100% had serum neutralizing antibodies (reciprocal titer > or = 10) to all three poliovirus types. No cases of paralytic poliomyelitis due to either wild or vaccine-related strains were reported. The project demonstrated the feasibility, safety, and high immunogenicity of sequential use of IPV followed by OPV in Romania.

Antibodies, Viral↗
PubMed1997

Outbreak of poliomyelitis in Gizan, Saudi Arabia: cocirculation of wild type 1 polioviruses from three separate origins.

In 1989, a localized outbreak of 10 cases of poliomyelitis occurred in Saudi Arabia. Wild poliovirus type 1 was isolated from 5 patients. To determine the patterns of poliovirus circulation, partial nucleotide sequences of the poliovirus isolates were compared. These isolates were remarkably diverse. Two isolates were closely related to each other and to viruses isolated during the 1988 epidemic in Oman. Two other isolates were very similar to viruses found in Egypt. The fifth isolate was distantly related to the latter pair. The molecular data suggest that the 10 cases represented three separate outbreaks. The virologic findings underscore the potential for Saudi Arabia, which receives millions of guest workers and their families each year from countries in which polio is endemic, to be exposed to frequent importations of wild polioviruses. To restrict the circulation of imported polioviruses, Saudi Arabia must maintain high population immunity to poliovirus in all geopolitical divisions.

Child↗
PubMed1997

Status of poliomyelitis eradication in Europe and the Central Asian republics of the former Soviet Union.

In the European Region of the World Health Organization, all countries in which polio is endemic have adopted the following strategies: achievement of high routine vaccination coverage, implementation of supplemental immunization activities, and enhancement of surveillance for poliomyelitis. In 1995, 205 cases of poliomyelitis were reported. Routine coverage among 1-year-olds with three doses of poliovirus vaccine was 89% in 1995. Ten countries conducted national immunization days (NIDs). Twenty-four countries (48%) adopted acute flaccid paralysis (AFP) surveillance. Use of NIDs has decreased poliomyelitis incidence in the seven countries in which polio is endemic (Armenia, Azerbaijan, Kazakhstan, Turkey, Turkmenistan, Tajikistan, Uzbekistan) from 203 cases in 1994 to 47 in 1995, a 77% reduction. Full implementation of the strategies to achieve eradication in the countries in which polio is endemic, including those countries with epidemic poliovirus transmission during 1995, is likely to accomplish regional eradication of poliomyelitis by the year 2000 or earlier.

Asia, Central↗
PubMed1997

A large outbreak of poliomyelitis following temporary cessation of vaccination in Samarkand, Uzbekistan, 1993-1994.

Oral poliovirus vaccine (OPV) was not available in Samarkand, Uzbekistan, from November 1992 to August 1993. The ensuing outbreak of poliomyelitis was investigated: Patients with poliomyelitis were evaluated, the extent of poliovirus circulation was estimated, and the effectiveness of control measures was assessed. Between March 1993 and April 1994, 74 cases of paralytic disease attributable to poliovirus type 3 were reported. Cases originated from 63% of districts; 88% of cases were children < or = 2 years old, and the highest attack rates were for infants 9-11 months (65/100,000) and 12-14 months (60/100,000). Most patients were either unvaccinated (45%) or inadequately vaccinated (23%). Limited quantities of OPV became available in September 1993 and were provided to infants (3 doses) and 1-year-olds (2 doses), controlling rapidly the outbreak in these age groups, but cases continued, primarily among older children, until April 1994. These findings suggest that control efforts should be guided by the age distribution of the children with poliomyelitis.

Age Distribution↗
PubMed1996

Cost-effectiveness of incorporating inactivated poliovirus vaccine into the routine childhood immunization schedule.

OBJECTIVE: To evaluate the economic consequences of introducing inactivated poliovirus vaccine (IPV) into the routine vaccination schedule in the United States to reduce vaccine-associated paralytic poliomyelitis (VAPP). DESIGN: Cost-benefit and cost-effectiveness models were formulated to compare the current national 4-dose live attenuated oral poliovirus vaccine (OPV) schedule with a 4-dose IPV schedule or a sequential schedule of 2 doses of IPV followed by 2 doses of OPV. Model assumptions were derived from the National Health Interview Survey (1994), current prices for OPV and IPV, a Delphi panel, compensatory awards by the National Vaccine Injury Compensation Program, and published and unpublished reports. MAIN OUTCOME MEASURES: Annual societal incremental cost relative to the current schedule for the cost-benefit model; cost per VAPP case prevented for the cost-effectiveness model. RESULTS: Changing to an IPV-only or a sequential schedule would cost $28.1 million and $14.7 million, respectively. The costs per case of VAPP prevented were estimated as $3.0 million and $3.1 million for each option, respectively. Outcomes were most sensitive to the number of additional visits that may occur to avoid multiple injections. CONCLUSIONS: The introduction of IPV into the routine vaccination schedule would not be cost-beneficial at current vaccine prices and with the current compensation awards paid to VAPP cases. The analysis provides a range of costs that policymakers need to consider if they wish to prevent VAPP. Although these costs are higher than those of other public health prevention programs, they may be justified because VAPP continues to occur as a result of government-mandated vaccination policies in the absence of known wild poliovirus transmission in the United States.

Child↗
PubMed1996

Current situation and control strategies for resurgence of diphtheria in newly independent states of the former Soviet Union.

Since 1990, an epidemic of diphtheria has spread throughout the newly independent states of the former Soviet Union, and by 1995 a total of 47 808 cases were reported. During the early stages of the epidemic, adequate control measures were not taken and vaccine was in short supply; possible contributing factors to the spread of the epidemic are the presence of highly susceptible child and adult populations, socioeconomic instability, population movement, and a deteriorating health infrastructure. Although WHO views the epidemic as an International public-health emergency and, together with UNICEF and the International Red Cross, has formulated a strategy to combat the epidemic, the necessary funds have not been made fully available. Current vaccination recommendations also need to be reviewed to ensure that population immunity will be adequate to prevent any resurgence of diphtheria in Europe and North America.

Age Distribution↗