Variation in provider vaccine purchase prices and payer reimbursement

OBJECTIVE

The purpose of this work was to collect data regarding vaccine prices and reimbursements in private practices. Amid reports of physicians losing money on vaccines, there are limited supporting data to show how much private practices are paying for vaccines and how much they are being reimbursed by third-party payers.

METHODS

We conducted a cross-sectional survey of a convenience sample of private practices in 5 states (California, Georgia, Michigan, New York, and Texas) that purchase vaccines for administration to privately insured children/adolescents. Main outcome measures included prices paid to purchase vaccines recommended for children and adolescents and reimbursement from the 3 most common, non-Medicaid payers for vaccine purchase and administration.

RESULTS

Detailed price and reimbursement data were provided by 76 practices. There was a considerable difference between the maximum and minimum prices paid by practices, ranging from $4 to more than $30 for specific vaccines. There was also significant variation in insurance reimbursement for vaccine purchase, with maximum and minimum reimbursements for a single vaccine differing from $8 to more than $80. Mean net yield per dose (reimbursement for vaccine purchase minus price paid per dose) varied across vaccines from a low of approximately $3 to more than $24. Reimbursement for the first dose of vaccine administered ranged from $0 to more than $26, with a mean of $16.62.

CONCLUSIONS

There is a wide range of prices paid by practices for the same vaccine product and in the reimbursement for vaccines and administration fees by payers. This variation highlights the need for individual practices to understand their own costs and reimbursements and to seek opportunities to reduce costs and increase reimbursements.

Primary care physician perspectives on reimbursement for childhood immunizations

OBJECTIVES

The purpose of this research was to explore physicians' attitudes and behaviors related to vaccine financing issues within their practice. Amid the increasing number of vaccine doses recommended for children and adolescents, anecdotal reports suggest that physicians are facing increasing financial pressures from vaccine purchase and administration and may stop providing vaccines altogether to privately insured children. Whether these sentiments are widely held among immunization providers is unknown.

METHODS

We conducted a cross-sectional mail survey from July to September 2007 of a random sample of 1280 US pediatricians and family physicians engaged in direct patient care. Main outcome measures included delay in the purchase of specific vaccines for financial reasons; reported decrease in profit margin from immunizations; and practice consideration of whether to stop providing all vaccines to privately insured children.

RESULTS

The response rate was 70% for pediatricians and 60% for family physicians. Approximately half of the respondents reported that their practice had delayed the purchase of specific vaccines for financial reasons (49%) and experienced decreased profit margin from immunizations (53%) in the previous 3 years. Twenty-one percent of respondents strongly disagreed that "reimbursement for vaccine purchase is adequate," and 17% strongly disagreed that "reimbursement for vaccine administration is adequate." Eleven percent of respondents said their practice had seriously considered whether to stop providing all vaccines to privately insured children in the previous year.

CONCLUSIONS

Physicians who provide vaccines to children and adolescents report dissatisfaction with reimbursement levels and increasing financial strain from immunizations. Although large-scale withdrawal of immunization providers does not seem to be imminent, efforts to address root causes of financial pressures should be undertaken.

Attitudes of US obstetricians toward a combined tetanus-diphtheria-acellular pertussis vaccine for adults

OBJECTIVE

To describe obstetricians' perspectives related to tetanus-diphtheria-acellular pertussis (Tdap) vaccination of mothers and other adults in close contact with infants.

METHODS

Mail survey of national random sample of 400 obstetricians.

RESULTS

Response rate was 54%. Most respondents would likely recommend Tdap for women during the postpartum hospital stay (78%) or during pregnancy (69%) if a national recommendation was issued. Expected barriers were knowing the date of patients' most recent Td booster (74%) and patient resistance (46%). Most felt that obstetricians have a role in promoting and administering Tdap vaccine to adults other than mothers likely to come in close contact with infants.

CONCLUSION

Obstetricians are likely to agree with the recent provisional US recommendation to administer Tdap to postpartum mothers and other adults expected to come in close contact with infants. Obstetricians would also be likely to support a potential recommendation to administer Tdap during pregnancy. Barriers to adoption of new Tdap vaccine recommendations should be monitored.

New combined tetanus-diptheria-acellular pertussis vaccines for adults: primary care physician attitudes and preferences

Availability of combined tetanus-diphtheria-acellular pertussis (Tdap) vaccines for adults offers a new pertussis prevention strategy for the US. Successful uptake of Tdap vaccine will depend partly on the attitudes and practices of primary care physicians, including their experience with Td boosters. We conducted a mail survey in August 2005 of a national random sample of 399 family physicians (FPs) and 399 general internists (IMs) to assess practices related to Td boosters, clinical experience with pertussis, and attitudes toward a potential Tdap vaccine recommendation for adults. The response rate was 49% (52% FPs, 46% IMs). Among 336 eligible respondents, half reported having clinical experience with pertussis. Most (81%) would recommend Tdap vaccine for their adult patients, and 73% support targeting adults likely to come in close contact with infants. Attitudes toward a potential Tdap vaccine recommendation differed by whether providers stock and administer Td boosters. We conclude that adult primary care providers in the US are likely to recommend Tdap vaccine to their adult patients, in concordance with recent national recommendations. Future research should assess the extent to which barriers impede adoption of Tdap vaccine recommendations.

Physician attitudes regarding breakthrough varicella disease and a potential second dose of varicella vaccine

OBJECTIVE

We assessed physicians' attitudes about the 1-dose varicella vaccination program and whether physicians think a 2-dose recommendation is needed to reduce the risk of breakthrough disease.

METHODS

We conducted a national mail survey of a random sample of 550 pediatricians and 550 family physicians from April to June 2005. Physicians who provide outpatient primary care to children < or = 6 years of age were eligible for analysis.

RESULTS

Surveys were returned by 727 respondents, for a response rate of 69%; 610 physicians were eligible. Most respondents (94%) recommend routine 1-dose varicella vaccination, and 79% have seen breakthrough disease in the past 5 years (95% of pediatricians and 58% of family physicians). The majority (68%) agreed or strongly agreed that the current burden of breakthrough disease is acceptable. Only 38% (46% of pediatricians and 28% of family physicians) agreed or strongly agreed that a second dose of varicella vaccine is needed to address the burden of breakthrough disease, whereas 40% were neutral. However, if the Advisory Committee on Immunization Practices were to recommend a second dose of varicella vaccine, then 65% of pediatricians and 39% of family physicians would likely follow the recommendation. Most respondents (78%) would be more willing to recommend a second dose if a combination measles-mumps-rubella-varicella vaccine was available.

CONCLUSIONS

Pediatricians and family physicians support the 1-dose varicella vaccination program. A new Advisory Committee on Immunization Practices recommendation for a second dose of varicella vaccine for children was issued after the survey (in June 2006). Two of 3 pediatricians and 2 of 5 family physicians stated that they would adopt a 2-dose recommendation in practice; rates of adoption may be bolstered with current availability of measles-mumps-rubella-varicella vaccine and harmonization of the varicella vaccination schedule with that of measles-mumps-rubella vaccine.

Physician perspectives to inform a new recommendation for meningococcal conjugate vaccine (MCV4)

PURPOSE

In January 2005, the U.S. Food and Drug Administration licensed a new tetravalent meningococcal conjugate vaccine (MCV4). Before any policy decisions by the U.S. Advisory Committee on Immunization Practices (ACIP) related to MCV4, the Centers for Disease Control and Prevention requested a study to explore the perspective of primary care physicians regarding different recommendation scenarios for use of MCV4.

METHODS

Cross-sectional mail survey of a national random sample of pediatricians (PDs) and family physicians (FPs), conducted January 2005. Respondents chose from four MCV4 recommendation scenarios in terms of ability to implement, perceived patient/parent preferences, scientific evidence, and overall best fit.

RESULTS

Response rate to the single-mailing survey was 57%. In terms of ability to implement, respondents generally preferred an MCV4 recommendation targeted to middle-school entry (11-12 years old) or with the Td booster at any age, but on the basis of scientific evidence they favored MCV4 at high school completion. For "overall best fit," relatively equal proportions of respondents favored a recommendation at middle school entry and one linked to Td booster administration (whenever it occurred); there were no significant differences between PDs and FPs. Major influences on willingness to recommend MCV4 were vaccine safety/side effects and insurance coverage/reimbursement.

CONCLUSIONS

Support for an MCV4 recommendation at middle school entry is common but not universal among primary care providers. Data suggest that respondents appreciate the potential discrepancy between practical aspects of vaccine delivery and the need to protect those adolescents at greatest risk of disease. Respondents' preferences for the overall best fit appear to prioritize ease of implementation over epidemiologic patterns.

Physician attitudes and preferences about combined Tdap vaccines for adolescents

BACKGROUND

Combined tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap) boosters for adolescents are a new strategy to prevent pertussis. We examined the current practices of pediatricians and family physicians regarding adolescent tetanus and diphtheria toxoids (Td) vaccine immunizations and providers' potential adherence to new Tdap recommendations for adolescents.

METHODS

Using a brief survey instrument sent to a random sample of pediatricians and family physicians in January 2005, we assessed providers' patterns of administration of Td boosters, barriers to Td boosters, and agreement that pertussis vaccination of adolescents is warranted. Results of analyses in February 2005 were presented to the Advisory Committee on Immunization Practices of the Centers for Disease Control and Prevention (CDC) to inform its deliberations regarding adolescent Tdap vaccination.

RESULTS

The overall response rate was 56% (57% pediatricians, 55% family physicians). Among 297 respondents (154 pediatricians, 143 family physicians) eligible for analysis because they provide care to adolescents, pediatricians (77%) were significantly more likely than family physicians (51%, p < 0.0001) to report that they routinely administer Td at preventive care visits for adolescents aged 11 to 12 years, but otherwise the specialties were similar in their Td practices. Forty-four percent of respondents cited infrequency of adolescent visits as a barrier to Td immunization. Slightly more than half the sample (57%) agreed or strongly agreed that pertussis is serious enough to warrant replacing Td with Tdap for adolescents; pediatricians (70%) were significantly more likely than family physicians (42%, p < 0.0001) to endorse this statement.

CONCLUSIONS

This national survey indicates moderate willingness, stronger among pediatricians than among family physicians, to support recommendations for Tdap among adolescents. In February 2006, CDC released recommendations that adolescents aged 11 to 18 (preferred age 11 to 12) receive a single dose of Tdap in place of Td if they have not already received the latter. Near-term efforts regarding Tdap recommendations must address providers' concerns about infrequent routine visits for adolescents and convince more physicians of the importance of pertussis booster immunization during adolescence.

Use of a new combined vaccine in pediatric practices

OBJECTIVE

On December 13, 2002, Pediarix, a combination vaccine that contains diphtheria, tetanus, acellular pertussis; hepatitis B; and inactivated polio vaccines, was licensed by the Food and Drug Administration for use in the primary immunization series. Use of this vaccine decreases the number of injections that children receive when completing their primary immunization series at the 2-, 4-, and 6-month well-child visits. The objective of this study was to determine the factors that influence the use of this combined vaccine in private pediatric practices, with particular attention to the perceived economic impact of Pediarix and actions taken to address this impact within the private pediatric setting.

METHODS

A mail survey study was conducted of a random sample of 565 practicing pediatricians that was obtained from the American Medical Association Masterfile. Frequency distributions were developed for all responses, and the vaccine financing policies of the state of practice for each respondent were determined. Chi2 analysis was performed to assess any associations of the predictor variables with the outcome variables of interest, use or consideration of use of the Pediarix vaccine. Logistic regression was used to determine the independent association of the predictor variables with use or consideration of use of Pediarix. Regression models that did and did not include practice ownership as a predictor variable were developed.

RESULTS

Response rate was 63% (N = 355). A total of 39% (n = 123) of the respondents' practices were purchasing Pediarix for use with their private patients. An additional 18% (n = 55) were considering purchasing the vaccine. Those who were in practices that were owned by hospitals or health systems were more likely than those who were in solo or group practices to purchase Pediarix for their private patients. Approximately half of the remaining respondents order Pediarix through their state immunization program. Among the 52% of respondents who did not, 23% reported that the vaccine was not yet available through their state program, and 47% stated that they did not want to use different vaccines for their public and private patients. Only 11% believed that Pediarix was not compatible with their other vaccine products. Physicians that currently were purchasing or considering purchasing Pediarix were more likely to be influenced by both parental and provider desire to decrease the number of injections at a single visit and the reduced time for immunization delivery. Fewer than 1% of respondents reported either having experienced or expecting to experience a significant decrease in practice revenue as a result of the use of Pediarix.

CONCLUSIONS

Although use of the vaccine results in fewer administration fees for most physicians, the magnitude of the change seemed not to be significant for the majority of respondents or was outweighed by other factors. It also is possible that larger practices or buying cooperatives were able to negotiate discounted rates for Pediarix relative to the constituent products. This may have been a strategy of manufacturers and/or distributors to provide incentive for practices to switch to the combination product. Of note was the appreciation of respondents for the preferences of patients for fewer vaccines and, to a lesser degree, for the decrease in office staff time required to provide vaccination with multiple antigens when using Pediarix. Also, the role of the availability of a given vaccine through the Vaccines for Children program is important in its adoption into practice.

Influenza vaccination status and influenza-related perspectives and practices among US physicians

BACKGROUND AND OBJECTIVE

The influenza vaccination rate among US healthcare workers (HCWs) remains low. This survey was designed to assess influenza vaccination status and related knowledge, attitudes, and beliefs among a national sample of primary care physicians and subspecialists likely to see patients at high risk for complications from influenza.

METHODS

We used a mail survey of a national random sample of 495 family physicians (FPs), 491 internists (IMs), 498 geriatricians (GERs), and 497 pulmonologists (PUDs).

RESULTS

The overall response rate was 38%. Almost all respondents (87%) reported receiving an influenza vaccine during the 2003-2004 influenza season, with no significant difference across specialty groups (84% FPs, 87% IMs, 87% GERs, 91% PUDs). In a multivariate model, adjusted for physician specialty and age group, significant predictors of vaccination were: strong agreement that HCWs have professional responsibility to be vaccinated, access to vaccination on site and free of charge, strong worksite recommendation for HCWs to be vaccinated, and strong agreement that benefits of vaccination outweigh risk of side effects.

CONCLUSIONS

Physicians reported a high influenza vaccination rate. To improve these rates further, with likely benefits for other HCWs, worksite policies that facilitate access to vaccination and documentation of reductions in nosocomial influenza associated with HCW vaccination should continue to be pursued.

Private provider participation in statewide immunization registries

Background

Population-based registries have been promoted as an effective method to improve childhood immunization rates, yet rates of registry participation in the private sector are low. We sought to describe, through a national overview, the perspectives of childhood immunization providers in private practice regarding factors associated with participation or non-participation in immunization registries.

Methods

Two mailed surveys, one for 264 private practices identified as registry non-participants and the other for 971 identified as registry participants, from 15 of the 31 states with population-based statewide immunization registries. Frequency distributions were calculated separately for non-participants and participants regarding the physician-reported factors that influenced decisions related to registry participation. Pearson chi-square tests of independence were used to assess associations among categorical variables.

Results

Overall response rate was 62% (N = 756). Among non-participants, easy access to records of vaccines provided at other sites (N = 101, 68%) and printable immunization records (N = 82, 55%) were most often cited as "very important" potential benefits of a registry, while the most commonly cited barriers to participation were too much cost/staff time (N = 36, 38%) and that the practice has its own system for recording and monitoring immunizations (N = 35, 37%). Among registry participants, most reported using the registry to input data on vaccines administered (N = 326, 87%) and to review immunization records of individual patients (N = 302, 81%). A minority reported using it to assess their practice's immunization coverage (N = 110, 29%) or generate reminder/recall notices (N = 54, 14%). Few participants reported experiencing "significant" problems with the registry; the most often cited was cost/staff time to use the registry (N = 71, 20%).

Conclusion

Most registry participants report active participation with few problems. The problems they report are generally consistent with the barriers anticipated by non-participants, but did not impede participation. Recruitment efforts should focus on demonstrating the benefits of the registry to providers. In addition, many participants are not utilizing the full range of registry features; further study is needed to determine how best to increase use of these features.

Willingness of Private Physicians to Be Involved in Smallpox Preparedness and Response Activities

BACKGROUND

The public health system continues its efforts to prepare for bioterrorist events, such as a smallpox outbreak, but may need to call on other health professionals to ensure sufficient capacity to implement preparedness plans.

OBJECTIVE

The goal was to understand the willingness of primary care physicians to participate in possible smallpox pre- or post-event activities.

METHODS

A 23-question mail survey was sent to a national random sample of 727 internists and 720 family physicians. After three mailings, a one-page version of the survey was sent to nonrespondents.

RESULTS

Response rates were 26% for questions common to both surveys and 22% for questions on the longer survey only. Respondents to the survey expressed moderate support for participating in certain smallpox pre- and post-event activities. Under a pre-event scenario, many providers would be willing to vaccinate first responders in their practice, and roughly one-third would be willing to vaccinate patients in their practice or to work in a public health clinic as a vaccinator. Most physicians, however, would be unwilling to be vaccinated themselves. Under post-event conditions, most providers would be willing to vaccinate their own patients, and many would vaccinate other community members in their practice.

CONCLUSIONS

Despite the low response rate, information from this study on the smallpox preparedness activities in which physicians are most willing to participate can help to inform efforts by public health officials and private physicians to collaborate on bioterrorism preparedness efforts.

Hospital Decision-Making Regarding the Smallpox Pre-Event Vaccination Program

OBJECTIVES

To understand the factors underlying the decision by U.S. hospitals to participate or not in the U.S. Smallpox Pre-Event Vaccination Program (SPVP).

METHODS

We conducted semistructured telephone interviews with a convenience sample of 123 hospital decision-makers in nine states between June and November 2003.

RESULTS

Within our sample, 88 hospitals (72%) decided to participate in the SPVP and 35 (28%) decided against doing so. Nearly all hospital decision-makers considered the risk of a smallpox outbreak, risks associated with vaccination, hospital costs, and the reaction of hospital stakeholders. However, these factors often were weighed differently by hospitals that decided to participate compared to those that did not. Fewer than half of all hospitals reported that public health officials played an important role in their decision-making process, but those that did felt the influence of public health officials was positive.

CONCLUSIONS

Strengthening the linkage between the public and private health sectors may help to address some of the barriers to broader participation by hospitals in the SPVP and foster the success of smallpox outbreak response preparedness efforts in the future.

Emergency department use among Michigan children with special health care needs: an introductory study

OBJECTIVE

To describe patterns of emergency department (ED) use among children dual-enrolled in Medicaid and Michigan's Children's Special Health Care Services (CSHCS).

DATA SOURCES

Individual claims and enrollment data from Michigan's Medicaid and CSHCS programs for the period January 1, 1998, to June 30, 1999. Claims data were linked with eligibility data and then used to develop a 100 percent sample of claims for individuals enrolled in both Medicaid and CSHCS.

STUDY DESIGN

Poisson regression analysis was used to examine the rate of ED use for dual-enrolled children. A time-varying hazard analysis was also used to examine the impact of changes over time. The key variables were gender, age, race, county of residence, Medicaid eligibility category, and qualifying diagnosis.

PRINCIPAL FINDINGS

Dual-enrolled children under one year of age, and those with qualifying diagnoses of anemia, hemophilia, asthma, epilepsy, and juvenile diabetes displayed especially high rates of ED use. Significant geographic variation in ED use remained after controlling for qualifying diagnoses, race/ethnicity, and other factors. African Americans displayed higher rates of ED utilization than non-Hispanic whites. Supplemental Security Income (SSI) recipients demonstrated higher utilization than other groups.

CONCLUSIONS

Children dually enrolled in CSHCS and Medicaid face diverse challenges of both poverty and chronic illness. Differences in patterns of use highlight the importance, but also the difficulty, of developing systems of care to manage complex chronic conditions in low-income populations.

Germination of spores of Bacillus subtilis with dodecylamine

AIMS

To determine the properties of Bacillus subtilis spores germinated with the alkylamine dodecylamine, and the mechanism of dodecylamine-induced spore germination.

METHODS AND RESULTS

Spores of B. subtilis prepared in liquid medium were germinated efficiently by dodecylamine, while spores prepared on solid medium germinated more poorly with this agent. Dodecylamine germination of spores was accompanied by release of almost all spore dipicolinic acid (DPA), degradation of the spore's peptidoglycan cortex, release of the spore's pool of free adenine nucleotides and the killing of the spores. The dodecylamine-germinated spores did not initiate metabolism, did not degrade their pool of small, acid-soluble spore proteins efficiently and had a significantly lower level of core water than did spores germinated by nutrients. As measured by DPA release, dodecylamine readily induced germination of B. subtilis spores that: (a) were decoated, (b) lacked all the receptors for nutrient germinants, (c) lacked both the lytic enzymes either of which is essential for cortex degradation, or (d) had a cortex that could not be attacked by the spore's cortex-lytic enzymes. The DNA in dodecylamine-germinated wild-type spores was readily stained, while the DNA in dodecylamine-germinated spores of strains that were incapable of spore cortex degradation was not. These latter germinated spores also did not release their pool of free adenine nucleotides.

CONCLUSIONS

These results indicate that: (a) the spore preparation method is very important in determining the rate of spore germination with dodecylamine, (b) wild-type spores germinated by dodecylamine progress only part way through the germination process, (c) dodecylamine may trigger spore germination by a novel mechanism involving the activation of neither the spore's nutrient germinant receptors nor the cortex-lytic enzymes, and (d) dodecylamine may trigger spore germination by directly or indirectly activating release of DPA from the spore core, through the opening of channels for DPA in the spore's inner membrane.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results provide new insight into the mechanism of spore germination with the cationic surfactant dodecylamine, and also into the mechanism of spore germination in general. New knowledge of mechanisms to stimulate spore germination may have applied utility, as germinated spores are much more sensitive to processing treatments than are dormant spores.

Primary care pediatrician knowledge of nutritional rickets

OBJECTIVE

The purpose of this study is to determine primary care pediatricians' level of awareness in the diagnosis and management of rickets. The information will be useful in assessing the need for provider education related to appropriate advice regarding vitamin D supplementation for infants.

STUDY DESIGN

A one-page questionnaire was sent to a sample of 510 pediatricians in states surrounding the Great Lakes. These physicians were chosen depending based on practice listings from local telephone directories. Results were analyzed using the Chi-squared (chi2) test.

RESULTS

Of the 248 respondents, 43% (n = 105) had encountered at least one actual or suspected case of rickets in the past five years. Sixty-nine percent of respondents chose vitamin D deficiency rickets-specific diagnostic tests, 24% chose rickets-specific tests, and 7% chose tests that are not specific to diagnosing rickets. Ninety-four percent of respondents chose treatments specific to vitamin D deficiency rickets, while 6% chose treatments not specific to rickets.

CONCLUSION

Most primary care pediatricians from major metropolitan areas in the Great Lakes region are aware of the appropriate methods to diagnose and treat vitamin D-deficiency rickets. However, educational interventions are still necessary for both physicians and parents to promote widespread use of vitamin D supplementation in all breastfed infants.

Studies on the mechanism of killing of Bacillus subtilis spores by hydrogen peroxide

AIMS

To determine the mechanism of killing of Bacillus subtilis spores by hydrogen peroxide.

METHODS AND RESULTS

Killing of spores of B. subtilis with hydrogen peroxide caused no release of dipicolinic acid (DPA) and hydrogen peroxide-killed spores were not appreciably sensitized for DPA release upon a subsequent heat treatment. Hydrogen peroxide-killed spores appeared to initiate germination normally, released DPA and hydrolysed significant amounts of their cortex. However, the germinated killed spores did not swell, did not accumulate ATP or reduced flavin mononucleotide and the cores of these germinated spores were not accessible to nucleic acid stains.

CONCLUSIONS

These data indicate that treatment with hydrogen peroxide results in spores in which the core cannot swell properly during spore germination.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results provide further information on the mechanism of killing of spores of Bacillus species by hydrogen peroxide.

Mechanisms of killing spores of Bacillus subtilis by acid, alkali and ethanol

AIMS

To determine the mechanisms of killing of Bacillus subtilis spores by ethanol or strong acid or alkali.

METHODS AND RESULTS

Killing of B. subtilis spores by ethanol or strong acid or alkali was not through DNA damage and the spore coats did not protect spores against these agents. Spores treated with ethanol or acid released their dipicolinic acid (DPA) in parallel with spore killing and the core wet density of ethanol- or acid-killed spores fell to a value close to that for untreated spores lacking DPA. The core regions of spores killed by these two agents were stained by nucleic acid stains that do not penetrate into the core of untreated spores and acid-killed spores appeared to have ruptured. Spores killed by these two agents also did not germinate in nutrient and non-nutrient germinants and were not recovered by lysozyme treatment. Spores killed by alkali did not lose their DPA, did not exhibit a decrease in their core wet density and their cores were not stained by nucleic acid stains. Alkali-killed spores released their DPA upon initiation of spore germination, but did not initiate metabolism and degraded their cortex very poorly. However, spores apparently killed by alkali were recovered by lysozyme treatment.

CONCLUSIONS

The data suggest that spore killing by ethanol and strong acid involves the disruption of a spore permeability barrier, while spore killing by strong alkali is due to the inactivation of spore cortex lytic enzymes.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results provide further information on the mechanisms of spore killing by various chemicals.

Guinea pig fertilin exhibits restricted lateral mobility in epididymal sperm and becomes freely diffusing during capacitation

The guinea pig sperm protein fertilin functions in sperm-egg plasma membrane binding. Fertilin is initially present in the plasma membrane of the whole head in testicular sperm, then becomes concentrated into the posterior head domain during epididymal passage. Fertilin remains localized to the posterior head plasma membrane following the acrosome reaction, when it functions in sperm-egg interaction. Fluorescence redistribution after photobleaching was used to examine the lateral mobility of fertilin in both acrosome-intact and acrosome-reacted sperm. Fertilin exhibited highly restricted lateral mobility in both testicular and epididymal sperm (D < 10(-10) cm(2)/s). However, fertilin in acrosome-reacted sperm was highly mobile within the membrane bilayer (D = 1.8 x 10(-9) cm(2)/s and %R = 84). Measurement of the lateral mobility of fertilin in capacitated, acrosome-intact sperm revealed two populations of cells. In approximately one-half of the cells, lateral mobility of fertilin was similar to sperm freshly isolated from the cauda epididymis; while in the other half fertilin was highly mobile. The release of fertilin from interactions that restrict its lateral mobility may regulate its function in sperm-egg interaction.

State-level perspectives on immunization policies, practices, and program financing in the 1990s

This article reports on a series of structured interviews with immunization program officials in all 50 states regarding the effects of changes in federal policies and funding in the 1990s on the goals, priorities, and activities of state immunization programs. The purchase of vaccines is a major component of all state immunization programs. The Vaccines for Children (VFC) program, implemented in 1994, has become the primary source of vaccine purchase support in almost all states. A concern of many state immunization programs is their ability to ensure that vaccines are available to children who are not VFC eligible.State immunization programs also are involved in a myriad of activities necessary to ensure that children are adequately and appropriately immunized (e.g. , vaccine administration, outreach to parents). Federal funding to support these activities increased significantly during the mid-1990s, but was substantially reduced beginning in 1997. Because of these funding decreases, most states had to reduce the scale and scope of their immunization activities.State-level funding support for immunization programs varies, with state governments more likely to support vaccine purchase than immunization activities. Immunization will never be completed. Along with each new birth cohort, changes to the primary immunization schedule (i.e., addition of new vaccines and expansion of existing recommendations to encompass broader target groups) create ongoing needs for vaccine purchase and other immunization activities. Long-term immunization planning must reflect these continually expanding needs.

Analysis of nucleoid morphology during germination and outgrowth of spores of Bacillus species

After a few minutes of germination, nucleoids in the great majority of spores of Bacillus subtilis and Bacillus megaterium were ring shaped. The major spore DNA binding proteins, the alpha/beta-type small, acid-soluble proteins (SASP), colocalized to these nucleoid rings early in spore germination, as did the B. megaterium homolog of the major B. subtilis chromosomal protein HBsu. The percentage of ring-shaped nucleoids was decreased in germinated spores with lower levels of alpha/beta-type SASP. As spore outgrowth proceeded, the ring-shaped nucleoids disappeared and the nucleoid became more compact. This change took place after degradation of most of the spores' pool of major alpha/beta-type SASP and was delayed when alpha/beta-type SASP degradation was delayed. Later in spore outgrowth, the shape of the nucleoid reverted to the diffuse lobular shape seen in growing cells.

Barriers to diffusion of plasma membrane proteins form early during guinea pig spermiogenesis

The plasma membrane of the mature guinea pig sperm is segregated into at least four domains of different composition. Previous studies have shown that some proteins localized within these domains are free to diffuse laterally, suggesting that barriers to protein diffusion are responsible for maintaining the nonuniform distribution of at least some surface proteins in mature sperm. The different membrane domains appear sequentially during sperm morphogenesis in the testis and during later passage through the epididymis. To determine when diffusion barriers become functional during sperm development, we examined the diffusion of two proteins that are expressed on the cell surface of developing spermatids and become segregated to different plasma membrane domains during the course of spermiogenesis. Both proteins exhibited rapid lateral diffusion throughout spermiogenesis, even after they become localized to specific regions of the surface membrane. These results suggest that barriers to membrane diffusion form concomitantly with membrane domains during spermiogenesis.

Analysis of the relationship between the decrease in pH and accumulation of 3-phosphoglyceric acid in developing forespores of Bacillus species

Analysis of the pH decrease and 3-phosphoglyceric acid (3PGA) accumulation in the forespore compartment of sporulating cells of Bacillus subtilis showed that the pH decrease of 1 to 1.2 units at approximately 4 h of sporulation preceded 3PGA accumulation, as observed previously in B. megaterium. These data, as well as analysis of the forespore pH decrease in asporogenous mutants of B. subtilis, indicated that sigma G-dependent forespore transcription, but not sigma K-dependent mother cell transcription, is required for the forespore pH decrease. Further analysis of these asporogenous mutants showed an excellent correlation between the forespore pH decrease and the forespore's accumulation of 3PGA. These latter results are consistent with our previous suggestion that the decrease in forespore pH results in greatly decreased activity of phosphoglycerate mutase in the forespore, which in turn leads to 3PGA accumulation. In further support of this suggestion, we found that (i) elevating the pH of developing forespores of B. megaterium resulted in rapid utilization of the forespore's 3PGA depot and (ii) increasing forespore levels of PGM approximately 10-fold in B. subtilis resulted in a large decrease in the spore's depot of 3PGA. The B. subtilis strain with a high phosphoglycerate mutase level sporulated, and the spores germinated and went through outgrowth normally, indicating that forespore accumulation of a large 3PGA depot is not essential for these processes.