Global VAX: A U.S. contribution to global COVID-19 vaccination efforts, 2021-2023

In December 2021 the U.S. Government announced a new, whole-of-government $1.8 billion effort, the Initiative for Global Vaccine Access (Global VAX) in response to the global COVID-19 pandemic. Using the foundation of decades of U.S. government investments in global health and working in close partnership with local governments and key global and multilateral organizations, Global VAX enabled the rapid acceleration of the global COVID-19 vaccine rollout in selected countries, contributing to increased COVID-19 vaccine coverage in some of the world's most vulnerable communities. Through Global VAX, the U.S. Government has supported 125 countries to scale up COVID-19 vaccine delivery and administration while strengthening primary health care systems to respond to future health crises. The progress made by Global VAX has paved the way for a stronger global recovery and improved global health security.

Endoprosthetic reconstruction for lower extremity soft tissue sarcomas with bone involvement

BACKGROUND AND OBJECTIVES

Bone resection and endoprosthetic reconstruction (EPR) in the setting of soft tissue sarcoma (STS) management is rare and incurs unique challenges. We aim to report on the surgical and oncological outcomes of this relatively previously undocumented cohort.

METHODS

This is a single-center retrospective review of prospectively collected data for patients who required EPRs following resection of STSs of the lower extremity. Following inclusion criteria, we assessed 29 cases of EPR for primary STS of the lower limb.

RESULTS

The mean age was 54 years (range 18-84). Of the 29 patients, there were 6 total femur, 11 proximal femur, 4 intercalary, and 8 distal femur EPRs. Fourteen of 29 patients (48%) underwent re-operations for surgical complications, with 9 relating to infection (31%). When a matched cohort analysis was performed comparing our cohort to STSs that did not necessitate EPR, a reduced rate of overall survival and metastasis-free survival was found in those requiring EPR.

CONCLUSION

This series identifies a high rate of complication from EPRs performed for STS. Patients should be cautioned about the high rate of infection, surgical complications, and lower overall survival in this setting.

Pneumococcal Meningitis Outbreaks in Africa, 2000-2018: Systematic Literature Review and Meningitis Surveillance Database Analyses

BACKGROUND

The meningitis belt of sub-Saharan Africa has traditionally experienced large outbreaks of meningitis mainly caused by Neisseria meningitidis. More recently, Streptococcus pneumoniae has been recognized as a cause of meningitis outbreaks in the region. Little is known about the natural history and epidemiology of these outbreaks, and, in contrast to meningococcal meningitis, there is no agreed definition for a pneumococcal meningitis epidemic. The aim of this analysis was to systematically review and understand pneumococcal meningitis outbreaks in Africa between 2000 and 2018.

METHODS

Meningitis outbreaks were identified using a systematic literature review and analyses of meningitis surveillance databases. Potential outbreaks were included in the final analysis if they reported at least 10 laboratory-confirmed meningitis cases above baseline per week with ≥50% of cases confirmed as pneumococcus.

RESULTS

A total of 10 potential pneumococcal meningitis outbreaks were identified in Africa between 2000 and 2018. Of these, 2 were classified as confirmed, 7 were classified as possible, and 1 was classified as unlikely. Three outbreaks spanned more than 1 year. In general, the outbreaks demonstrated lower peak attack rates than meningococcal meningitis outbreaks and had a predominance of serotype 1. Patients with pneumococcal meningitis tended to be older and had higher case fatality rates than meningococcal meningitis cases. An outbreak definition, which includes a weekly district-level incidence of at least 10 suspected cases per 100 000 population per week, with >10 cumulative confirmed cases of pneumococcus per year, would have identified all 10 potential outbreaks.

CONCLUSIONS

Given the frequency of and high case fatality from pneumococcal meningitis outbreaks, public health recommendations on vaccination strategies and the management of outbreaks are needed. Improved laboratory testing for S. pneumoniae is critical for early outbreak identification.

Modeling Optimal Laboratory Testing Strategies for Bacterial Meningitis Surveillance in Africa

Since 2010, the introduction of an effective serogroup A meningococcal conjugate vaccine has led to the near-elimination of invasive Neisseria meningitidis serogroup A disease in Africa’s meningitis belt. However, a significant burden of disease and epidemics due to other bacterial meningitis pathogens remain in the region. High-quality surveillance data with laboratory confirmation is important to monitor circulating bacterial meningitis pathogens and design appropriate interventions, but complete testing of all reported cases is often infeasible. Here, we use case-based surveillance data from 5 countries in the meningitis belt to determine how accurately estimates of the distribution of causative pathogens would represent the true distribution under different laboratory testing strategies. Detailed case-based surveillance data was collected by the MenAfriNet surveillance consortium in up to 3 seasons from participating districts in 5 countries. For each unique country-season pair, we simulated the accuracy of laboratory surveillance by repeatedly drawing subsets of tested cases and calculating the margin of error of the estimated proportion of cases caused by each pathogen (the greatest pathogen-specific absolute error in proportions between the subset and the full set of cases). Across the 12 country-season pairs analyzed, the 95% credible intervals around estimates of the proportion of cases caused by each pathogen had median widths of ±0.13, ±0.07, and ±0.05, respectively, when random samples of 25%, 50%, and 75% of cases were selected for testing. The level of geographic stratification in the sampling process did not meaningfully affect accuracy estimates. These findings can inform testing thresholds for laboratory surveillance programs in the meningitis belt.

Coronavirus Disease 2019 (COVID-19) in Americans Aboard the Diamond Princess Cruise Ship

Background

The Diamond Princess cruise ship was the site of a large outbreak of coronavirus disease 2019 (COVID-19). Of 437 Americans and their travel companions on the ship, 114 (26%) tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Methods

We interviewed 229 American passengers and crew after disembarkation following a ship-based quarantine to identify risk factors for infection and characterize transmission onboard the ship.

Results

The attack rate for passengers in single-person cabins or without infected cabinmates was 18% (58/329), compared with 63% (27/43) for those sharing a cabin with an asymptomatic infected cabinmate, and 81% (25/31) for those with a symptomatic infected cabinmate. Whole genome sequences from specimens from passengers who shared cabins clustered together. Of 66 SARS-CoV-2-positive American travelers with complete symptom information, 14 (21%) were asymptomatic while on the ship. Among SARS-CoV-2-positive Americans, 10 (9%) required intensive care, of whom 7 were ≥70 years.

Conclusion

Our findings highlight the high risk of SARS-CoV-2 transmission on cruise ships. High rates of SARS-CoV-2 positivity in cabinmates of individuals with asymptomatic infections suggest that triage by symptom status in shared quarters is insufficient to halt transmission. A high rate of intensive care unit admission among older individuals complicates the prospect of future cruise travel during the pandemic, given typical cruise passenger demographics. The magnitude and severe outcomes of this outbreak were major factors contributing to the Centers for Disease Control and Prevention’s decision to halt cruise ship travel in U.S. waters in March 2020.

Meningococcal carriage 7 years after introduction of a serogroup A meningococcal conjugate vaccine in Burkina Faso: results from four cross-sectional carriage surveys

BACKGROUND

In the first 2 years after a nationwide mass vaccination campaign of 1-29-year-olds with a meningococcal serogroup A conjugate vaccine (MenAfriVac) in Burkina Faso, carriage and disease due to serogroup A Neisseria meningitidis were nearly eliminated. We aimed to assess the long-term effect of MenAfriVac vaccination on meningococcal carriage and herd immunity.

METHODS

We did four cross-sectional studies of meningococcal carriage in people aged 9 months to 36 years in two districts of Burkina Faso between May 2, 2016, and Nov 6, 2017. Demographic information and oropharyngeal swabs were collected. Meningococcal isolates were characterised using whole-genome sequencing.

FINDINGS

Of 14 295 eligible people, 13 758 consented and had specimens collected and laboratory results available, 1035 of whom were meningococcal carriers. Accounting for the complex survey design, prevalence of meningococcal carriage was 7·60% (95% CI 5·67-9·52), including 6·98% (4·86-9·11) non-groupable, 0·48% (0·01-0·95) serogroup W, 0·10% (0·01-0·18) serogroup C, 0·03% (0·00-0·80) serogroup E, and 0% serogroup A. Prevalence ranged from 5·44% (95% CI 4·18-6·69) to 9·14% (6·01-12·27) by district, from 4·67% (2·71-6·64) to 11·17% (6·75-15·59) by round, and from 3·39% (0·00-8·30) to 10·43% (8·08-12·79) by age group. By clonal complex, 822 (88%) of 934 non-groupable isolates were CC192, all 83 (100%) serogroup W isolates were CC11, and nine (69%) of 13 serogroup C isolates were CC10217.

INTERPRETATION

Our results show the continued effect of MenAfriVac on serogroup A meningococcal carriage, for at least 7 years, among vaccinated and unvaccinated cohorts. Carriage prevalence of epidemic-prone serogroup C CC10217 and serogroup W CC11 was low. Continued monitoring of N meningitidis carriage will be crucial to further assess the effect of MenAfriVac and inform the vaccination strategy for future multivalent meningococcal vaccines.

FUNDING

Bill & Melinda Gates Foundation and Gavi, the Vaccine Alliance.

Improving Case-Based Meningitis Surveillance in 5 Countries in the Meningitis Belt of Sub-Saharan Africa, 2015–2017

Background

The MenAfriNet consortium was established in 2014 to support implementation of case-based meningitis surveillance in 5 countries in the meningitis belt of sub-Saharan Africa: Burkina Faso, Chad, Mali, Niger, and Togo. Assessing surveillance performance is critical for interpretation of the collected data and implementation of future surveillance-strengthening initiatives.

Methods

Detailed epidemiologic and laboratory data were collected on suspected meningitis cases through case-based meningitis surveillance in participating districts in 5 countries. Performance of case-based surveillance was evaluated through sensitivity of case ascertainment in case-based versus aggregate meningitis surveillance and an analysis of surveillance indicators.

Results

From 2015 to 2017, 18 262 suspected meningitis cases were identified through case-based surveillance and 16 262 were identified through aggregate surveillance, for a case ascertainment sensitivity of 112.3%. Among suspected cases, 16 885 (92.5%) had a cerebrospinal fluid (CSF) specimen collected, 13 625 (80.7%) of which were received at a national reference laboratory. Among these, 13 439 (98.6%) underwent confirmatory testing, and, of those tested, 4371 (32.5%) were confirmed for a bacterial pathogen.

Conclusions

Overall strong performance for case ascertainment, CSF collection, and laboratory confirmation provide evidence for the quality of MenAfriNet case-based surveillance in evaluating epidemiologic trends and informing future vaccination strategies.

Correction: Identifying Optimal Vaccination Strategies for Serogroup A Neisseria meningitidis Conjugate Vaccine in the African Meningitis Belt

[This corrects the article DOI: 10.1371/journal.pone.0063605.].

Rupture of a Cyst during Compression at Mammography

The pressure at dedicated mammographic units, indicated by a manometer, shows the pressure in the hydraulic system. The reading of this instrument is misleading because the pressure in the breast caused by the compression plate is considerably lower. Appropriate compression during mammographic examination may, however, rupture cysts.

Calcifications in the Breast in Filaria Loa Infection

A 40-year-old patient underwent mammography for evaluation of a mass. Atypical calcifications were observed in the opposite breast. Two types of calcification were observed: one type was spiral-shaped and the other type rod-shaped. These calcifications were caused by Filaria loa. Parasitic calcifications in the breast are uncommon.

Emergence of epidemic Neisseria meningitidis serogroup C in Niger, 2015: an analysis of national surveillance data

BACKGROUND

To combat Neisseria meningitidis serogroup A epidemics in the meningitis belt of sub-Saharan Africa, a meningococcal serogroup A conjugate vaccine (MACV) has been progressively rolled out since 2010. We report the first meningitis epidemic in Niger since the nationwide introduction of MACV.

METHODS

We compiled and analysed nationwide case-based meningitis surveillance data in Niger. Cases were confirmed by culture or direct real-time PCR, or both, of cerebrospinal fluid specimens, and whole-genome sequencing was used to characterise isolates. Information on vaccination campaigns was collected by the Niger Ministry of Health and WHO.

FINDINGS

From Jan 1 to June 30, 2015, 9367 suspected meningitis cases and 549 deaths were reported in Niger. Among 4301 cerebrospinal fluid specimens tested, 1603 (37·3%) were positive for a bacterial pathogen, including 1147 (71·5%) that were positive for N meningitidis serogroup C (NmC). Whole-genome sequencing of 77 NmC isolates revealed the strain to be ST-10217. Although vaccination campaigns were limited in scope because of a global vaccine shortage, 1·4 million people were vaccinated from March to June, 2015.

INTERPRETATION

This epidemic represents the largest global NmC outbreak so far and shows the continued threat of N meningitidis in sub-Saharan Africa. The risk of further regional expansion of this novel clone highlights the need for continued strengthening of case-based surveillance. The availability of an affordable, multivalent conjugate vaccine may be important in future epidemic response.

FUNDING

MenAfriNet consortium, a partnership between the US Centers for Disease Control and Prevention, WHO, and Agence de Médecine Preventive, through a grant from the Bill & Melinda Gates Foundation.

Serogroup A meningococcal conjugate (PsA-TT) vaccine coverage and measles vaccine coverage in Burkina Faso--implications for introduction of PsA-TT into the Expanded Programme on Immunization

BACKGROUND

A new serogroup A meningococcal conjugate vaccine (PsA-TT, MenAfriVac™) has been developed to combat devastating serogroup A Neisseria meningitis (MenA) epidemics in Africa. A mass immunization campaign targeting 1-29 year olds was conducted in Burkina Faso in December 2010. Protection of subsequent infant cohorts will be necessary through either introduction of PsA-TT into the routine Expanded Programme on Immunization (EPI) or periodic repeat mass vaccination campaigns.

OBJECTIVES

To inform future immunization policy for PsA-TT vaccination of infants through a comparison of PsA-TT campaign vaccination coverage and routine measles-containing vaccine (MCV) coverage in Burkina Faso.

METHODS

A national survey was conducted in Burkina Faso during December 17-27, 2011 using stratified cluster sampling to assess PsA-TT vaccine coverage achieved by the 2010 nationwide immunization campaign among 2-30 year olds and routine MCV coverage among 12-23 month olds. Coverage estimates and 95% Confidence Intervals (CI) were calculated, reasons for non-vaccination and methods of campaign communication were described, and a multivariable analysis for factors associated with vaccination was conducted.

RESULTS

National overall PsA-TT campaign coverage was 95.9% (95% CI: 95.0-96.7) with coverage greater than 90% all 13 regions of Burkina Faso. National overall routine MCV coverage was 92.5% (95% CI: 90.5-94.1), but ranged from 75.3% to 95.3% by region. The primary predictor for PsA-TT vaccination among all age groups was a head of household informed of the campaign. PsA-TT vaccination was more likely in residents of rural settings, whereas MCV vaccination was more likely in residents of urban settings.

CONCLUSION

Overall national vaccination rates in Burkina Faso were similar for PsA-TT and MCV vaccine. The regions with MCV coverage below targets may be at risk for sub-optimal vaccination coverage if PsA-TT is introduced in EPI. These results highlight the need for assessments of routine vaccination coverage to guide PsA-TT immunization policy in meningitis belt countries.

Identifying optimal vaccination strategies for serogroup A Neisseria meningitidis conjugate vaccine in the African meningitis belt

Objective

The optimal long-term vaccination strategies to provide population-level protection against serogroup A Neisseria meningitidis (MenA) are unknown. We developed an age-structured mathematical model of MenA transmission, colonization, and disease in the African meningitis belt, and used this model to explore the impact of various vaccination strategies.

Methods

The model stratifies the simulated population into groups based on age, infection status, and MenA antibody levels. We defined the model parameters (such as birth and death rates, age-specific incidence rates, and age-specific duration of protection) using published data and maximum likelihood estimation. We assessed the validity of the model by comparing simulated incidence of invasive MenA and prevalence of MenA carriage to observed incidence and carriage data.

Results

The model fit well to observed age- and season-specific prevalence of carriage (mean pseudo-R2 0.84) and incidence of invasive disease (mean R2 0.89). The model is able to reproduce the observed dynamics of MenA epidemics in the African meningitis belt, including seasonal increases in incidence, with large epidemics occurring every eight to twelve years. Following a mass vaccination campaign of all persons 1–29 years of age, the most effective modeled vaccination strategy is to conduct mass vaccination campaigns every 5 years for children 1–5 years of age. Less frequent campaigns covering broader age groups would also be effective, although somewhat less so. Introducing conjugate MenA vaccine into the EPI vaccination schedule at 9 months of age results in higher predicted incidence than periodic mass campaigns.

Discussion

We have developed the first mathematical model of MenA in Africa to incorporate age structures and progressively waning protection over time. Our model accurately reproduces key features of MenA epidemiology in the African meningitis belt. This model can help policy makers consider vaccine program effectiveness when determining the feasibility and benefits of MenA vaccination strategies.

Phase II clinical study of BC-3781, a pleuromutilin antibiotic, in treatment of patients with acute bacterial skin and skin structure infections

This study investigated the potential of the novel systemic pleuromutilin antibiotic BC-3781 to treat patients with an acute bacterial skin and skin structure infection (ABSSSI) caused by a Gram-positive pathogen. Patients were randomized to intravenous BC-3781 100 mg, BC-3781 150 mg, or vancomycin 1 g every 12 h. Response to treatment was assessed daily and at test of cure (TOC). The primary endpoint was the clinical success rate at TOC in the modified intent-to-treat (MITT) and clinically evaluable (CE) analysis populations. Baseline characteristics, including the frequency of methicillin-resistant Staphylococcus aureus (MRSA), were comparable between the different treatment groups. Of 210 patients randomized, 186 (88.6%) patients completed the study. Clinical success at TOC in the CE population occurred in 54 (90.0%) patients in the BC-3781 100-mg group, 48 (88.9%) in the BC-3781 150-mg group, and 47 (92.2%) in the vancomycin group. At day 3, the clinical response rate was similar across the three treatment groups. Six patients discontinued study medication following an adverse event. The incidence rate for drug-related adverse events was lower for patients receiving BC-3781 (34.3% and 39.4% in the 100-mg and 150-mg groups, respectively) than those receiving vancomycin (53.0%). When BC-3781 was used to treat ABSSSIs caused by a Gram-positive pathogen, including MRSA, clinical success rates were comparable to those of the comparator, vancomycin. BC-3781 was generally well tolerated. These results provide the first proof of concept for the systemic use of a pleuromutilin antibiotic for the treatment of ABSSSIs.

Risk and prevention of acute urinary retention after robotic prostatectomy

PURPOSE

Acute urinary retention after catheter removal is a recognized complication following open or robot-assisted radical prostatectomy. We evaluated patient and surgery related risk factors to determine whether acute urinary retention could be prevented. To our knowledge this has not previously been investigated for prostatectomy done by any technique.

MATERIALS AND METHODS

We reviewed a single surgeon, robot-assisted radical prostatectomy database of patients treated between February 2008 and June 2011 for acute urinary retention after catheter removal, which was routinely performed 3 to 7 days postoperatively. We compared the characteristics of patients with and without acute urinary retention.

RESULTS

Of 1,026 patients 25 (2.4%) experienced acute urinary retention. There was no difference between patients with and without acute urinary retention in mean age, body mass index, blood loss or prostate size, and no difference in the frequency of bladder neck reconstruction or nerve sparing. The catheter was removed an average of 4.1 vs 5.7 days postoperatively in patients with vs without acute urinary retention. Of 25 patients with acute urinary retention 22 (88%) underwent catheter removal on postoperative day 3 or 4. Although only 3 of 381 patients (0.8%) had a leak on cystogram on postoperative day 3 or 4, the acute urinary retention rate when the catheter was removed on day 3 or 4 was 5.8% (22 of 381). This was several times higher than the rate in patients who retained the catheter for greater than 4 days (3 of 645 or 0.5%).

CONCLUSIONS

Acute urinary retention develops infrequently after robotic prostatectomy. No patient related risk factors were identified beyond catheterization time. Although the catheter may be removed after 3 or 4 days with rare leaks, the acute urinary retention risk was much less when the catheter was left in place at least 5 days.

The autoreactivity of B cells in hereditary angioedema due to C1 inhibitor deficiency

Patients with hereditary angioedema (HAE) tend to produce autoantibodies and have a propensity to develop immunoregulatory disorders. We characterize the profile of autoantibodies in a group of HAE patients and investigate their memory B cells' phenotype and activation status. We studied the activity status phenotype, Toll-like receptor (TLR)-9 expression and total phosphotyrosine in B cells isolated from HAE patients. Additionally, the following autoantibodies were assessed in the serum of 61 HAE patients: anti-nuclear, rheumatoid factor, anti-cardiolipin, anti-tissue transglutaminase, anti-endomysial, anti-Saccharomyces cerevisiae, anti-thyroid and anti-neutrophil cytoplasmic antibodies. In 47·5% of HAE patients we detected at least one of the tested autoantibodies. Expression of CD69, CD5 and CD21 was found to be significantly higher on memory B cells from HAE patients compared to healthy controls (4·59 ± 4·41 versus 2·06 ± 1·81, P = 0·04, 8·22 ± 7·17 versus 3·65 ± 3·78, P = 0·05, 2·43 ± 0·54 versus 1·92 ± 0·41, P = 0·01, respectively). Total phosphotyrosine in B cells from HAE patients was significantly higher compared to healthy controls (4·8 ± 1·1 versus 2·7 ± 1·3, P = 0·0003). Memory B cells isolated from the HAE group contained higher amounts of TLR-9 compared to healthy controls (8·17 ± 4·1 versus 4·56 ± 1·6, P = 0·0027). Furthermore, the expression of TLR-9 in memory B cells from HAE patients with autoantibodies was significantly higher than the control group (10 ± 4·7 versus 4·56 ± 1·6, P = 0·0002) and from that in HAE patients without autoantibodies (10 ± 4·7 versus 5·8 ± 0·9, P = 0·036). HAE patients have enhanced production of autoantibodies due most probably to the increased activation of B cells, which was found to be in association with a high expression of TLR-9.

Abundance of IFN-? and IFN-? mRNA in blood of resistant and susceptible chickens infected with Marek?s disease virus (MDV) or vaccinated with turkey herpesvirus; and MDV inhibition of subsequent induction of IFN gene transcription

The effects of the very virulent RB-1B strain of Marek's disease virus (MDV) and turkey herpesvirus (HVT), a vaccinal strain, on abundance of IFN mRNA in the blood were investigated. MDV and HVT infection did not change the circulating level of IFN-gamma mRNA 1 and 7 days p.i., but they increased IFN-alpha mRNA levels slightly in genetically susceptible (to tumour development) B(13)/B(13) chickens. The total number of circulating leukocytes was unchanged and increase in message was accompanied by an increase in circulating CD8alpha(+) and MHC Class II(+) cells. On the contrary, both viruses slightly increased IFN-gamma transcripts and decreased IFN-alpha transcripts in genetically resistant B(21)/B(21) chickens. Further, oncogenic MDV was able to block the response to inactivated Newcastle disease virus, a potent inducer of IFN, in both chicken lines. The inhibiting effect on transcription was present for both IFN at days 1 and 7 p.i. in susceptible B(13)/B(13) chickens, but only at day 7 p.i. in resistant B(21)/B(21) chickens. By contrast, non-oncogenic HVT did not interfere with induction of either message at one day p.i. and MDV had a more suppressive effect than HVT on IFN gene transcription 7 days p.i. in B(21)/B(21) chickens. Thus, the strong ability of MDV to block induction of IFN gene transcription detected in the blood as soon as one day after infection in susceptible chickens, as opposed to resistant chickens, not only causes immunosuppression but also may be related to the virus's oncogenicity.

Apoptosis-inducing factor mediates microglial and neuronal apoptosis caused by pneumococcus

Streptococcus pneumoniae is the major cause of bacterial meningitis and it damages the hippocampus by inducing neuronal apoptosis. The blocking of caspases provides only partial protection in experimental meningitis, which suggests that there is an additional apoptotic pathway. A trigger of this pathway is the bacterium itself, as exposure of microglia or neurons to live pneumococci induces rapid apoptosis. In this study, apoptosis was not associated with the activation of caspases-1-10 and was not inhibited by z-VAD-fmk, a broad-spectrum caspase inhibitor. Rather, apoptosis was attributed to damage to mitochondria, which was followed by the release of apoptosis-inducing factor (AIF) from the mitochondria, large-scale DNA fragmentation, and hypodiploidy. Furthermore, intracytoplasmatic microinjection of AIF-specific antiserum markedly impaired pneumococcus-induced apoptosis. These findings indicate that AIF may play a central role in brain cell apoptosis and bacterial pathogenesis.

Immune status assessment by abundance of IFN-alpha and IFN-gamma mRNA in chicken blood

Avian diseases, including such viral infection as infectious bursal disease, infectious anemia, and Marek's disease, often cause immunosuppression, leading to more severe infection, problems with secondary infection, and inadequate responses to vaccination. Immunosuppression thus causes serious economic losses in commercial poultry production. To date, methods for assessing immune status have been too slow to be of practical help. Reasoning that immunosuppression should be reflected by reduced production of interferons (IFN) in response to a viral antigen, we have developed competitive nucleic acid hybridization microtiter plate assays for chicken IFN-alpha (ChIFN-alpha) and ChIFN-gamma mRNA. To evaluate the assay, chickens were challenged with inactivated Newcastle disease virus (iNDV). Whole blood samples were collected at various times subsequently and preserved with a cationic detergent. Later, total RNA was extracted, and mRNA for both ChIFN-alpha and ChIFN-gamma was measured. Both rose from undetectable levels to reach a peak by 4 h, remained high for about 3 days, and fell to undetectable levels by day 5. Results were similar in chickens aged between 1 and 28 days. In later experiments, blood was collected 4 h after viral challenge. When chickens were immunosuppressed by administering 4-5 mg cyclophosphamide (CY) daily for 3 days and challenged with iNDV, they transcribed less ChIFN-alpha and ChIFN-gamma mRNA, and their antibody response was impaired. Our results suggest that suspected immunosuppression in a commercial flock could be assessed within 2-3 days by challenging birds with iNDV and measuring the amounts of ChIFN-alpha and ChIFN-gamma mRNA in blood obtained 2-4 h later.

The rationale and design of the CPCRA (Terry Beirn Community Programs for Clinical Research on AIDS) 058 FIRST (Flexible Initial Retrovirus Suppressive Therapies) trial

The CPCRA (Terry Beirn Community Programs for Clinical Research on AIDS) 058 FIRST (Flexible Initial Retrovirus Suppressive Therapies) trial is a large, long-term, randomized, prospective comparison of three different antiretroviral strategies in highly active antiretroviral therapy-naïve, HIV-1-infected persons. The trial was designed as a flexible framework upon which other studies could be added to answer more limited, but still important, questions. This article presents the study design, discusses the challenges we have faced in implementing the trial, and describes our preliminary experiences. Control Clin Trials 2001;22:176-190

Slovene smart card and IP based health-care information system infrastructure

Slovenia initiated a nation-wide project to introduce smart cards in the health sector in 1995 and its full-scale deployment started in September 2000. Although the basic aim of the project was to support insurance related procedures, the system was designed in a flexible and open manner to present an infrastructure for the whole health sector. The functionality of the current system is described in this paper along with lessons learned so far. The upgrade of the system is outlined, with emphasis on technical details, the objective being to provide a real-time EDI based environment for a general set of applications in the medical sector, supported by the flexibility and security of modern smart card technologies. Integration with similar systems in other EU countries is discussed.

Clinical isolates of Streptococcus pneumoniae that exhibit tolerance of vancomycin

The ability of Streptococcus pneumoniae to escape lysis and killing by vancomycin, a property termed "tolerance," has recently been noted in a laboratory strain of the species. Vancomycin tolerance in clinical isolates represents a potential new health risk. We determined the prevalence of vancomycin and penicillin tolerance among 116 clinical isolates of pneumococci by monitoring lysis and viability after exposure to the respective antibiotic for 4 hours. Eight percent of the strains were tolerant to penicillin and 3% were tolerant to vancomycin. The 3 vancomycin-tolerant isolates also had a high ratio of minimum bactericidal concentration to minimum inhibitory concentration, in contrast to nontolerant strains. They were of serotype 9V and had reduced susceptibility to penicillin. Only 1 was also tolerant to penicillin. Growth rate and ability to divide were not affected in the 3 vancomycin-tolerant strains, and they all lysed with deoxycholate, which indicates autolysin production. Vancomycin tolerance among clinical isolates of pneumococci will necessitate tracking to determine the magnitude of the evolving health risk, since tolerance may contribute to treatment failure (in particular, cases of meningitis, in which bactericidal activity is critical for eradication) and since it may also be a favored background for acquisition of resistance of vancomycin.

Competitive DNA hybridization in microtitre plates for chicken anaemia virus

Unlabelled chicken anaemia virus (CAV) DNA probe, produced by PCR, was immobilized onto nitrocellulose discs that then were fitted into microtitre plate wells in order to develop a competitive, non-radioactive hybridization test for detection of CAV. The discs were hybridized with either DNA extracts of buffy coats or dilutions of CAV DNA (for standard curves), followed by hybridization with biotin-labelled CAV DNA probe in excess of the immobilized, capture probe. Thus, CAV from sample DNA extracts and standard DNA preparations competed with the biotin-labelled CAV DNA probe for the immobilized, capture probe, decreasing subsequent colour development by an avidin-biotin-alkaline phosphatase detection system. Standard curves were log linear from 5-100 ng viral DNA with r(2)> or =0.91. Tests were considered positive at 2 SD less than mean absorbence of samples from uninfected chickens, and ranged from 52 to 108 microm viral DNA or 2 to 4.2x10(10)virions microg(-1)buffy coat DNA. Blood samples from chickens infected and not infected with CAV at one day of age were tested for evidence of infection until 28 days of age by viral isolation, competitive hybridization in microtitre plates, dot-blots, enzyme-linked immunosorbent assay (ELISA), and in situ hybridization on blood smears. None of the tests was positive for uninfected chickens. Viral isolation from buffy coats, though expensive and lengthy, was the most sensitive method. It detected virus in buffy coat from each infected chicken, while competitive hybridization detected 72% of infected chickens, in situ hybridization 69%, dot-blots 67%, and ELISA 36%. Sensitivity of competitive hybridization was 0.78, and its specificity was 1.00. Three chickens must be sampled from an infected flock for a 90% chance of detecting a positive chicken at the 0.025 one-tailed level of significance, assuming 100% prevalence.

Regulation of growth inhibition at high temperature, autolysis, transformation and adherence in Streptococcus pneumoniae by clpC

The ClpC ATPase is a subfamily of HSP100/Clp molecular chaperones-regulators of proteolysis. By screening a library of loss of function mutants for the ability to survive treatment with penicillin, we identified the gene clpC. The corresponding protein was identified as a ClpC ATPase, sharing strong peptide sequence identity with ClpC of Bacillus subtilis, Listeria monocytogenes and Lactococcus lactis. Northern blot experiments showed that expression of clpC was induced in response to high temperature (40-42 degrees C) versus 37 degrees C, suggesting that ClpC is a heat shock protein. Insertional duplication mutagenesis of clpC resulted in increased tolerance to high temperature; a result in contrast to other bacterial Clp proteases. The clpC-deficient mutant formed long chains and failed to undergo lysis after treatment with penicillin or vancomycin. The effect of the clpC mutation extended to deficiency of adherence to the human type II alveolar cells. Finally, the clpC disruption resulted in decreased genetic transformation. Western blot analysis demonstrated that the mutant failed to express pneumolysin and the choline-binding proteins LytA, CbpA, CbpE, CbpF, CbpJ. These results suggest that the heat shock protein ClpC plays an essential complex pleiotropic role in pneumococcal physiology, including cell growth under heat stress, cell division, autolysis, adherence and transformation.

Laboratory evaluations of methylated soy oil and monoterpenes as mosquito larvicides

The larvicidal toxicities of methylated soy oil (MSO) and surfactant combinations were compared to 2 commercially available oil larvicides (Golden Bear Oil 1111 and Bonide) in standard laboratory bioassays of 4th-stage larvae of Culex pipiens Linn. The dose lethal to 50% of the test organisms (LD50) and the dose lethal to 95% of the test organisms (LD95) values are presented as microliters (microl) per beaker (treatment surface area of 54 cm2). The 2 surfactant-MSO mixtures differed significantly in their toxicity to Cx. pipiens larvae; 2% Pyroter CPI-40 in MSO was more toxic than 2% Pluronic L121 in MSO (LD50 = 3.8 microl per 54 cm2 and 11.3 microl per 54 cm2, respectively). The 2 most active larvicides were Golden Bear Oil (LD50 = 3.6 microl per 54 cm2) and the 2% Pyroter-MSO mixture. These 2 were not significantly different from each other. Bonide (LD50 = 6.2 microl per 54 cm2) and the Pluronic L121-MSO mixture (LD50 = 11.3 microl per 54 cm2) were less toxic than Golden Bear Oil and the MSO-Pryroter mixture and they were significantly different from each other. Bioassays with 4th-stage larvae of Anopheles stephensi Liston showed that toxicity of the Pyroter-MSO formulations increased about 2-fold from 18 degrees C to 24 degrees C (LD50 = 20.5 microl per 54 cm2 and 11.8 microl per 54 cm2, respectively). The laboratory bioassays suggest that MSO mixed with surfactants are potential mosquito larvicides. We also evaluated the influence of the 2 surfactants on the toxicity of 3 monoterpenes. The larvicidal activity of citral and limonene increased with the addition of surfactants, but neither surfactant enhanced the toxicity of cineole. All 3 monoterpenes, with and without surfactants, were considered poor candidates as surface larvicides because of their high volatilities.

Extracellular targeting of choline-binding proteins in Streptococcus pneumoniae by a zinc metalloprotease

A genetic-based search for surface proteins of Streptococcus pneumoniae involved in adhesion identified a putative zinc metalloprotease (ZmpB). ZmpB shared high amino acid sequence similarities with IgA1 proteases of Gram-positive bacteria, but ZmpB had neither IgA1 nor IgA2 protease activity. Analysis of a family of surface-expressed proteins, the choline-binding proteins (Cbp's), in a zmpB-deficient mutant demonstrated a global loss of surface expression of CbpA, CbpE, CbpF and CbpJ. CbpA was detected within the cytoplasm. The zmpB-deficient mutant also failed to lyse with penicillin, a sign of lack of function of the Cbp LytA. Immunodetection studies revealed that the autolysin (LytA), normally located on the cell wall, was trapped in the cytoplasm colocalized with DNA and the transformation protein CinA. Trafficking of CinA and RecA to the cell membrane during genetic competence was also not observed in the zmpB-deficient mutant. These results suggest a protease dependent regulatory mechanism governing the translocation of CinA and the Cbp's LytA and CbpA of S. pneumoniae.

Uncontrolled oxygen administration and respiratory failure in acute asthma

STUDY OBJECTIVES

To determine if 100% oxygen administration adversely influences gas exchange in acutely ill asthmatic subjects.

DESIGN

Prospective preinterventional and postinterventional comparison.

SETTING

University hospital emergency department.

PATIENTS

Thirty-seven asthmatic subjects seeking care for symptomatic exacerbations.

INTERVENTIONS

Twenty minutes of 100% oxygen administration by face mask.

MEASUREMENTS AND RESULTS

Arterial blood gases and FEV(1) were measured before and during the last minute of oxygen administration. On presentation, the subjects had moderately severe airway obstruction (FEV(1), 49.1 +/- 3.6% of predicted); hypocarbia (PaCO(2), 36.8 +/- 1.1 mm Hg); hypoxemia (PaO(2), 70.2 +/- 2.5 mm Hg); and respiratory alkalosis (pH, 7.43 +/- 0.01). During oxygen breathing, 25 patients (67.6%) experienced elevations in PaCO(2) ranging from 1 to 10 mm Hg (mean, 4.1 +/- 0.6 mm Hg; p = 0.0003). The increase was considered to be a physiologic manifestation of the Haldane effect (ie, < or = 2 mm Hg) in 10 subjects, but in the remaining 15 subjects (40.5% of the total studied), the elevation represented worsening gas exchange. In seven of these patients (46.7%), hypercapnic respiratory failure developed (PaCO(2) before oxygen, 39.6 +/- 0.6; during oxygen, 44.7 +/- 0.7 mm Hg; p = 0.005), and in six patients (40%), it worsened (PaCO(2) before oxygen, 46.8 +/- 1.9; during oxygen, 52.0 +/- 3.1 mm Hg; p = 0.03). In general, the tendency toward hypercarbia was the greatest in the participants with the most severe airway obstructions.

CONCLUSIONS

Our data demonstrate that the administration of 100% oxygen to acutely ill asthmatics may adversely influence carbon dioxide elimination.

Signal transduction by a death signal peptide: uncovering the mechanism of bacterial killing by penicillin

The binding of bactericidal antibiotics like penicillins, cephalosporins, and glycopeptides to their bacterial targets stops bacterial growth but does not directly cause cell death. A second process arising from the bacteria itself is necessary to trigger endogenous suicidal enzymes that dissolve the cell wall during autolysis. The signal and the trigger pathway for this event are completely unknown. Using S. pneumoniae as a model, we demonstrate that signal transduction via the two-component system VncR/S triggers multiple death pathways. We show that the signal sensed by VncR/S is a secreted peptide, Pep27, that initiates the cell death program. These data depict a novel model for the control of bacterial cell death.

Isolation and characterization of vancomycin-tolerant Streptococcus pneumoniae from the cerebrospinal fluid of a patient who developed recrudescent meningitis

The emergence of tolerance to vancomycin has recently been reported in Streptococcus pneumoniae, the most common cause of bacterial meningitis. A vancomycin- and cephalosporin-tolerant strain of S. pneumoniae, the Tupelo strain, was isolated from the cerebrospinal fluid of a patient who then developed recrudescence of meningitis despite treatment with vancomycin and a third-generation cephalosporin. The Tupelo strain evidenced no lysis in the exponential or stationary phase of growth when exposed to vancomycin and only minimal loss of viability. Further characterization revealed normal autolysin expression, localization, and triggering by detergents, indicating that the defect leading to tolerance in the Tupelo strain is in the control pathway for triggering of autolysis. Because tolerance is a precursor phenotype to resistance and may lead to clinical failure of antibiotic therapy, these observations may have important implications for vancomycin use in infections caused by S. pneumoniae.

Modification of the Kock's pouch for bladder replacement

AIM

To describe a modification of the Kock's pouch and present our clinical experience in its application.

METHOD

After isolating an adequate ileal segment, the bowel is split by a longitudinal incision, with both ends remaining unopened for about 3-4 cm in length. Previously anastomozed ureters are inserted into the proximal end so that a nipple valve is created. The distal unsplit end serves for a direct anastomosis with the urethra. During the past 9 years, this surgery was performed in 41 patients who underwent radical cystectomy due to invasive carcinoma. Seventeen patients died for unknown reasons or were lost to follow-up. The remaining 24 were included in the follow-up for a period of 7 months to 6 years post surgery.

RESULTS

Half of the patients included in the follow-up urinated spontaneously, with post void residuals less than 120 mL and no need for catheterization. Four patients did not urinate spontaneously and needed continuos catheterization, whereas 8 patients had post void residuals of 150-200 mL and needed catheterization once a day or once a week. None of the patients had a stricture at the site of ureteroileal anastomosis.

CONCLUSION

We believe that our modification of the Kock's pouch makes the uretero-intestinal anastomosis much easier to perform; both ureters are inserted into the unsplit bowel end, thus preventing reflux; anastomosis with the urethra is performed under visual control; and direct anastomosis of widely opened distal end of the bowel reduces the possibility of scar stenosis.

Pathogenesis of pneumococcal pneumonia

Pneumococcal pneumonia is the most severe of the common community-acquired pulmonary infections. The recent release of the complete DNA sequence reveals the entire capability of the bacteria and the current challenge is to map gene products to the mechanics of disease. This process will reveal antibiotic targets and protein vaccine candidates crossing serotype boundaries. Choline is a major constituent of surfactant and it is also a required nutrient for the pneumococcus. It appears that choline incorporated into the cell wall can bind the bacteria to the receptor for platelet activating factor, the gateway to invasion. The choline also serves as an antenna to which multifunctional proteins dock, thereby decorating the bacterial surface. This set of 12 choline binding proteins is subject to phase variation of expression resulting in display of different combinations of proteins that adapt the bacteria to survival on the mucosa versus the blood stream. These changes affect protective antigens, adhesions, and lytic proteins tying together the major elements of pneumococcal physiology: natural DNA transformation, adherence and invasion of host cells, and autolysis. Taking these components and building an understanding of disease is challenging. Clearly, the toxin pneumolysin is a major mediator of cell damage in the lung. Inflammation is also incited by cell wall components. The signal transduction pathways that explain pneumococcal inflammation are more complex than those for gram-negative endotoxin.

Pneumolysin, a protein toxin of Streptococcus pneumoniae, induces nitric oxide production from macrophages

Nitric oxide (NO) production by inducible NO synthase (iNOS) during inflammation is an essential element of antimicrobial immunity but can also contribute to host-induced tissue damage. Under conditions of bacterial sepsis, large amounts of NO are produced, causing hypotension, a critical pathological feature of septic shock. In sepsis caused by gram-positive organisms, the bacterial factors contributing to host NO production are poorly characterized. We show that a soluble toxin of Streptococcus pneumoniae, pneumolysin (Pln), is a key component initiating NO production from macrophages. In contrast to wild-type bacteria, a mutant of S. pneumoniae lacking Pln failed to elicit NO production from murine macrophages. Purified recombinant Pln induced NO production at low concentrations and independently of exogenous gamma interferon (IFN-gamma) priming of RAW 264.7 macrophages. However, IFN-gamma was essential for Pln-induced NO production, since primary macrophages from mice lacking the IFN-gamma receptor or interferon regulatory factor 1, a transcription factor essential for iNOS expression, failed to produce NO when stimulated with Pln. In addition, Pln acts as an agonist of tumor necrosis factor alpha and interleukin 6 production in macrophages. The properties of Pln, previously identified as a pore-forming hemolysin, also include a role as a general inflammatory agonist.

Identification of two sources of carbon monoxide in comet Hale-Bopp

The composition of ices in comets may reflect that of the molecular cloud in which the Sun formed, or it may show evidence of chemical processing in the pre-planetary accretion disk around the proto-Sun. As carbon monoxide (CO) is ubiquitous in molecular clouds, its abundance with respect to water could help to determine the degree to which pre-cometary material was processed, although variations in CO abundance may also be influenced by the distance from the Sun at which comets formed. Observations have not hitherto provided an unambiguous measure of CO in the cometary ice (native CO). Evidence for an extended source of CO associated with comet Halley was provided by the Giotto spacecraft, but alternative interpretations exist. Here we report observations of comet Hale-Bopp which show that about half of the CO in the comet comes directly from ice stored in the nucleus. The abundance of this CO with respect to water (12 per cent) is smaller than in quiescent regions of molecular clouds, but is consistent with that measured in proto-stellar envelopes, suggesting that the ices underwent some processing before their inclusion into Hale-Bopp. The remaining CO arises in the coma, probably through thermal destruction of more complex molecules.

Emergence of vancomycin tolerance in Streptococcus pneumoniae

Streptococcus pneumoniae, the pneumococcus, is the most common cause of sepsis and meningitis. Multiple-antibiotic-resistant strains are widespread, and vancomycin is the antibiotic of last resort. Emergence of vancomycin resistance in this community-acquired bacterium would be catastrophic. Antibiotic tolerance, the ability of bacteria to survive but not grow in the presence of antibiotics, is a precursor phenotype to resistance. Here we show that loss of function of the VncS histidine kinase of a two-component sensor-regulator system in S. pneumoniae produced tolerance to vancomycin and other classes of antibiotic. Bacterial two-component systems monitor environmental parameters through a sensor histidine-kinase/phosphatase, which phosphorylates/dephosphorylates a response regulator that in turn mediates changes in gene expression. These results indicate that signal transduction is critical for the bactericidal activity of antibiotics. Experimental meningitis caused by the vncS mutant failed to respond to vancomycin. Clinical isolates tolerant to vancomycin were identified and DNA sequencing revealed nucleotide alterations in vncS. We conclude that broad antibiotic tolerance of S. pneumoniae has emerged in the community by a molecular mechanism that eliminates sensitivity to the current cornerstone of therapy, vancomycin.