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J Hedlund

Publications and source records attributed to J Hedlund.

At least 19 recordsLinked to original sources
PubMed2006

Non-response to specific serotypes likely cause for failure to 23-valent pneumococcal polysaccharide vaccine in the elderly.

During a randomised controlled trial with the 23-valent pneumococcal vaccine in older persons, antibody concentrations and opsonophagocytic activity (OPA) were compared between eight patients who developed culture-verified pneumococcal pneumonia and 38 controls, matched for age, sex and vaccination status. Patients who developed pneumococcal pneumonia did not respond with a significant increase of antibody concentration (>1microg/ml) post-vaccination to the infecting serotype, but responded equally well as controls to most other serotypes. Neither was there any significant difference in the OPA post-vaccination between patients and controls. In conclusion, the 23-valent pneumococcal vaccine should be regarded as 23 different vaccines, rather than one. Older persons who fail to respond to one serotype may well be protected against infection by the other 22 serotypes.

Age Factors↗
PubMed2004

Additive preventive effect of influenza and pneumococcal vaccines in elderly persons.

In 1999, all individuals > or = 65 yrs of age (n=258,754) in Stockholm County, Sweden, were offered influenza and pneumococcal vaccination in a prospective study on the effectiveness of these vaccines in reducing the need for hospital treatment and death due to influenza, pneumonia and invasive pneumococcal disease (IPD). Data on hospitalisation and mortality during 1 yr were obtained from the administrative database in Stockholm County Council. Vaccination was performed in 124,702 (48%) subjects; 72,107 had both vaccines, 29,346 only had the influenza vaccine and 23,249 only had the pneumococcal vaccine. Compared with the unvaccinated cohort, a lower incidence of hospitalisation for all endpoint diagnoses was seen in vaccinated persons. An additive effectiveness of vaccination was seen when both vaccines were given, with a reduction of hospital admissions for influenza (37%), pneumonia (29%) and IPD (44%). In-hospital mortality for pneumonia was significantly lower in those who received both vaccines, than in unvaccinated persons. To conclude, vaccination with influenza and pneumococcal vaccines together was effective in reducing the need for hospital admission for influenza and pneumonia. There was a strong indication that pneumococcal vaccination alone, was effective not only in the prevention of invasive pneumococcal disease, but also of pneumonia overall, although to a low degree.

Aged↗
PubMed2003

Effects of a large-scale intervention with influenza and 23-valent pneumococcal vaccines in elderly people: a 1-year follow-up.

To assess the effectiveness of influenza and pneumococcal vaccination in reducing hospitalisation and deaths in elderly people, the population aged > or =65 years in Stockholm County, Sweden (n = 259627) were invited to take part in a vaccination campaign with influenza and 23-valent pneumococcal vaccine (PV). A no. of persons (100,242) (vaccinated cohort) were vaccinated with one or both vaccines during the campaign. The incidence of hospital admissions during 1 year after the vaccination campaign, adjusted for sex and age, was significantly lower in the vaccinated than in the unvaccinated cohort for influenza (relative risk [RR] 0.68), pneumonia (RR 0.78), and invasive pneumococcal disease (RR 0.46). In the vaccinated cohort, the in-hospital mortality was lower for pneumonia (RR 0.55), COPD (RR 0.53) and cardiac failure (RR 0.72).

Aged↗
PubMed2001

Negligible adjuvant effect for antibody responses and frequent adverse events associated with IL-12 treatment in humans vaccinated with pneumococcal polysaccharide.

To assess whether co-administration of recombinant human IL-12 (rhIL-12) and 23-valent pneumococcal polysaccharide vaccine (PPV) enhances the antibody response to this T cell-independent antigen, healthy immunocompetent volunteers (n=34, 55-65 years old) were vaccinated intramusculary with PPV and concurrently-treated subcutaneously with either rhIL-12 (1 or 4 microg) or placebo. The increases of total anti-pneumococcal IgG antibodies were numerically higher among the rhIL-12 recipients compared with placebo recipients, but the difference was not significant. The rhIL-12 recipients had a high incidence of local and systemic side effects. Given the lack of convincing evidence that rhIL-12 enhances the antibody response to PPV, the frequency and severity of the side effects was unacceptable.

Adjuvants, Immunologic↗
PubMed2001

Dynamics of penicillin-susceptible clones in invasive pneumococcal disease.

In a 10-year period, 1987-1997, there was a >4-fold increase in the rate of pneumococcal bacteremia in Sweden. Invasive pneumococcal isolates (n=1136), which were obtained from 18 Swedish clinical microbiology laboratories from 1987 through 1997, and other national and international isolates were serotyped, and their clonal relationships were determined by molecular typing. The increase in invasive pneumococcal disease in Sweden during this period was associated particularly with an increase in isolates of serotypes 1 and 14. A 3-fold increase of type 14 was seen from 1987 through 1992, and a 10-fold increase of type 1 occurred from 1992 through 1997. One dominating penicillin-susceptible clone of type 14 was responsible for the increase of type 14 during the first 5 years. This clone also was found in Canada and the United States and was shown by multilocus sequence typing to correspond to a previously identified hyper-virulent clone. A novel penicillin-susceptible clone of type 1, which was not found among invasive isolates from 1987 or 1992, was responsible for the increase of serotype 1 during the last 5 years. These results illustrate the ability of virulent penicillin-susceptible pneumococcal clones to emerge and spread rapidly within a country.

Alleles↗
PubMed2001

Effects of a large-scale intervention with influenza and 23-valent pneumococcal vaccines in adults aged 65 years or older: a prospective study.

BACKGROUND: The effectiveness of influenza and pneumococcal vaccination in the prevention of hospital admissions and death has not been assessed prospectively. We have therefore examined the effects of influenza and pneumococcal vaccination in individuals aged 65 years and older in a 3-year prospective study, between Dec 1, 1998 and May 31, 1999. METHODS: All individuals in Stockholm County aged 65 years or older (259,627) were invited to take part in a vaccination campaign against influenza and pneumococcal infection. We recorded for all vaccine recipients (100,242) name, and date of birth, and whether they had been given both or one of the vaccines. All individuals (> or = 65 years) admitted to hospital in Stockholm County with influenza and pneumonia related diagnoses were identified between Dec 1, 1998, and May 31, 1999. FINDINGS: The incidence (per 100,000 inhabitants per year) of hospital treatment was lower in the vaccinated than in the unvaccinated cohort for all diagnoses: 263 versus 484 (-46% [95% CI 34-56]) for influenza; 2199 versus 3097 (-29% [24-34)) for pneumonia; 64 versus 100 (-36% [3-58]) for pneumococcal pneumonia; and 20 versus 40 (-52% [1-77]) for invasive pneumococcal disease. The total mortality was 57% (55-60) lower in vaccinated than in unvaccinated individuals (15.1 vs 34.7 deaths per 1000 inhabitants). INTERPRETATION: These findings show that general vaccination leads to substantial health benefits and to a reduction of mortality from all causes in this age group.

Aged↗
PubMed2001

Changes in serotype distribution may hamper efficacy of pneumococcal conjugate vaccines in children.

During the last 10 y we have observed an increased incidence of pneumococcal bacteremia in Sweden. In order to study the serotype distribution over time we collected 1136 invasive pneumococcal isolates from 1987, 1992 and 1997 from Swedish microbiological laboratories. Currently, new pneumococcal conjugate vaccines are being considered for introduction in the general childhood vaccination program in several countries, including Sweden. We studied the potential vaccine coverage rate for the new conjugate vaccines among our Swedish invasive isolates. We found that the serotype distribution fluctuated with time and observed a surprisingly low potential coverage rate for the 7-valent vaccine in Sweden, in contrast to other countries. Therefore we argue that pneumococcal conjugate vaccines have to be tailored to suit current, local serotype patterns and most likely will need to be changed over time.

Adolescent↗
PubMed2000

Recurrence of pneumonia in relation to the antibody response after pneumococcal vaccination in middle-aged and elderly adults.

We have recently studied the efficacy of pneumococcal vaccine in preventing pneumonia recurrences after hospital treatment for community-acquired pneumonia in non-immunocompromised patients aged 50-85 y. Among these patients, we have now compared the antibody response to the pneumococcal vaccine between patients who developed pneumonia (n = 50) and patients without pneumonia recurrences (n = 100), during a mean follow-up period of 32 months after vaccination. The antibody levels of 5 pneumococcal serotypes were measured before, and 4 weeks, 1 y and 3 y after vaccination. A lower risk of pneumonia recurrences was seen in patients with antibody fold increases (FIs) > 4 from pre-vaccination to post-vaccination compared with patients with lower FIs (p = 0.02). The results suggest that in this patient category, the antibody response to pneumococcal vaccination is of importance for the risk of pneumonia recurrence.

Aged↗
PubMed1999

[The elderly should be vaccinated against pneumococci].

Invasive pneumococcal diseases are associated with substantial mortality in the elderly. The incidence of such diseases, particularly that of bacteraemic pneumococcal pneumonia, has increased in Sweden during the past decade. At the same time, there is a growing problem with beta-lactam-resistant and multiresistant pneumococci in many nearlying countries. Although pneumococcal vaccine probably provides only limited protection against pneumococcal pneumonia in the elderly, it yields approximately 70 per cent protection against invasive pneumococcal disease. Pneumococcal vaccination should therefore be recommended to all those 65 years old and above, and a nationwide strategy developed to implement good coverage in the age group.

Aged↗
PubMed1998

Randomised trial of 23-valent pneumococcal capsular polysaccharide vaccine in prevention of pneumonia in middle-aged and elderly people. Swedish Pneumococcal Vaccination Study Group.

BACKGROUND: We assessed the effectiveness of a 23-valent pneumococcal vaccine in the prevention of pneumococcal pneumonia and of pneumonia overall in non-immunocompromised middle-aged and elderly people. METHODS: The prospective, multicentre, double-blind, randomised, placebo-controlled trial was carried out across departments of infectious diseases at six tertiary-care or university hospitals in Sweden. 691 non-immunocompromised patients aged 50-85 years who had been treated as inpatients for community-acquired pneumonia (CAP) were randomly assigned either 23-valent pneumococcal capsular polysaccharide vaccine or placebo (sodium chloride). We used Cox regression models to estimate the relative risks of pneumonia overall and pneumococcal pneumonia for the placebo group compared with the vaccine group. FINDINGS: 63 (19%) of 339 patients in the vaccine group and 57 (16%) of 352 patients in the placebo group developed a new pneumonia, corresponding to a relative risk over time for the placebo group compared with the vaccine group of 0.83 (95% CI 0.58-1.12, p=0.31). Pneumococcal pneumonia was diagnosed in 16 (4.5%) patients in the placebo group and in 19 (5.6%) in the vaccine group, corresponding to a relative risk for the placebo group of 0.78 (95% CI 0.40-1.51, p=0.45). We found no difference in the death rate between the two study groups. INTERPRETATION: The 23-valent pneumococcal polysaccharide vaccine did not prevent pneumonia overall or pneumococcal pneumonia in middle-aged and elderly individuals.

Aged↗
PubMed1998

Decision Accuracy in Computer-Mediated versus Face-to-Face Decision-Making Teams.

Changes in the way organizations are structured and advances in communication technologies are two factors that have altered the conditions under which group decisions are made. Decisions are increasingly made by teams that have a hierarchical structure and whose members have different areas of expertise. In addition, many decisions are no longer made via strictly face-to-face interaction. The present study examines the effects of two modes of communication (face-to-face or computer-mediated) on the accuracy of teams' decisions. The teams are characterized by a hierarchical structure and their members differ in expertise consistent with the framework outlined in the Multilevel Theory of team decision making presented by Hollenbeck, Ilgen, Sego, Hedlund, Major, and Phillips (1995). Sixty-four four-person teams worked for 3 h on a computer simulation interacting either face-to-face (FtF) or over a computer network. The communication mode had mixed effects on team processes in that members of FtF teams were better informed and made recommendations that were more predictive of the correct team decision, but leaders of CM teams were better able to differentiate staff members on the quality of their decisions. Controlling for the negative impact of FtF communication on staff member differentiation increased the beneficial effect of the FtF mode on overall decision making accuracy. Copyright 1998 Academic Press.

Journal Article↗
PubMed1997

[A handling program for resistant pneumococci. Physicians sometimes neglect mandatory notification].

Streptococcus pneumoniae infections belong to the leading worldwide causes of illness and death among young children, people with underlying debilitating medical conditions, and the elderly. Following early documentation of infections due to pneumococcal strains with reduced penicillin susceptibility in Australia in 1967, and of infections due to penicillin-resistant strains in South Africa in 1978, pneumococcal resistance to penicillin and other antibiotics has progressed rapidly and is now a global problem. In Sweden, notification of the occurrence of pneumococci with a minimum inhibitory concentration (MIC) > or = 0.5 mg/L for penicillin G (PcG) has been mandatory for general practitioners (GPs) and clinical microbiological laboratories since 1 January 1996. In 1996, 1,057 cases of infection by such pneumococci were reported by microbiological laboratories, but only 262 cases by GPs. With a view to minimising the impact of pneumococci with reduced penicillin susceptibility in Sweden, the National Board of Health and Welfare set up a working group of experts in November 1994. To reduce the transmission of such bacteria in the community, the working group introduced a control programme which includes the isolation of day-care children under six years of age carrying pneumococci with PcG-MICs > or = 0.5 mg/L. An enquiry among the 25 regional centres for infectious disease control in the country to ascertain compliance in the different counties of Sweden showed the programme to have been adhered to in a majority of counties, although many had chosen alternative measures to deal with the problem.

Disease Notification↗
PubMed1997

Recurrence of pneumonia in middle-aged and elderly adults after hospital-treated pneumonia: aetiology and predisposing conditions.

In order to investigate the predisposing conditions and aetiologic agents in patients with recurrent pneumonia, we prospectively studied 653 immunocompetent patients, 50-85 years of age, who had been treated in hospital for community-acquired pneumonia. After an average patient follow-up period of 32 months, 11 variables were examined for association with the following end points: death, recurrence of pneumonia and recurrence of pneumococcal pneumonia. During the follow-up period there were 171 episodes of pneumonia in 115 of the 653 patients, and 52 deaths (all causes). Multivariate analysis showed that age, male sex, congestive heart failure and presence of other chronic diseases were significantly associated with higher mortality. Age and chronic pulmonary disease were associated with recurrence of pneumonia. The major aetiologic agents were Streptococcus pneumoniae (26%), Haemophilus influenzae (11%) and Moraxella catarrhalis (6%). We conclude that pneumonia recurrences are common in middle-aged and elderly patients after treatment in hospital for community-acquired pneumonia. The recurrence risk is higher in elderly patients, and in those with chronic pulmonary diseases. Given the prominence of H. influenzae and M. catarrhalis found in the present study, these organisms should always be considered when choosing the initial antibiotic in patients with recurrent pneumonia.

Age Factors↗
PubMed1996

Activity of trovafloxacin against blood isolates of Streptococcus pneumoniae in Sweden.

The in vitro activity of the fluoroquinolone trovafloxacin (CP-99,219) against 257 blood isolates of Streptococcus pneumoniae obtained from Swedish hospitals was compared with those of commonly prescribed oral antibiotics and also with those of ciprofloxacin and ofloxacin against a collection of strains resistant (n = 6) or intermediately resistant (n = 22) to penicillin (Pc-R). The MICs of trovafloxacin for Pc-R strains of pneumococci ranged from 0.032 to 0.25 mg/l. No difference was seen between the clinical isolates and the Pc-R strains (MIC50 = 0.064 mg/l and MIC90 = 0.125 mg/l for both collections). For the Pc-R strains, the MIC50 and MIC90 values of ciprofloxacin were 0.5 and 1 mg/l, and those of ofloxacin 2 and 4 mg/l. The incidence of resistance in the two collections (clinical isolates/Pc-R strains) was 3%/39% for tetracycline, 1%/18% for macrolides, and 3%/57% for trimethoprim/sulfamethoxazole. The results of the current study suggest that the clinical efficacy of trovafloxacin in the treatment of pneumococcal infections should be investigated.

Anti-Infective Agents↗