Infectious Disease News
Bacteriophages Can Treat and Prevent Pseudomonas aeruginosa Lung Infections
Antibiotic‐resistant bacteria threaten life worldwide. Although new antibiotics are scarce, the use of bacteriophages, viruses that infect bacteria, is rarely proposed as a means of offsetting this shortage. Doubt also remains widespread about the efficacy of phage therapy despite recent encouraging results. Using a bioluminescent Pseudomonas aeruginosa strain, we monitored and quantified the efficacy of a bacteriophage treatment in mice during acute lung infection. Bacteriophage treatment not only was effective in saving animals from lethal infection, but also was able to prevent lung infection when given 24 h before bacterial infection, thereby extending the potential use of bacteriophages as therapeutic agents to combat bacterial lung infection.
An Algorithm for Tuberculosis Screening and Diagnosis in People with HIV
Tuberculosis screening is recommended for people with human immunodeficiency virus (HIV) infection to facilitate early diagnosis and safe initiation of antiretroviral therapy and isoniazid preventive therapy. No internationally accepted, evidence-based guideline addresses the optimal means of conducting such screening, although screening for chronic cough is common. A study in the New England Journal of Medicine consecutively enrolled people with HIV infection from eight outpatient clinics. The presence of cough of any duration, fever of any duration, or night sweats lasting 3 or more weeks in the preceding 4 weeks was 93% sensitive and 36% specific for tuberculosis.In persons with HIV infection, screening for tuberculosis should include asking questions about a combination of symptoms rather than only about chronic cough. It is likely that antiretroviral therapy and isoniazid preventive therapy can be started safely in people whose screening for all three symptoms is negative, whereas diagnosis in most others will require mycobacterial culture.
Risk Factors for Treatment Failure in Patients Receiving Vancomycin for Hospital-Acquired Methicillin-Resistant Staphylococcus aureus Pneumonia
The rate of vancomycin failure in patients with hospital-acquired pneumonia (HAP) caused by methicillin-resistant Staphylococcus aureus (MRSA) has exceeded 40% in several studies. This observation was attributed initially to the lack of weight-based dosing and targeting of lower trough concentrations. However, a subsequent study demonstrated no additional benefit in patients who achieved trough vancomycin concentrations >15mg/L compared with patients with concentrations between 5 and 15mg/L. A study out of Surgical Infections sought to identify contributors to vancomycin failure in patients with MRSA HAP and found data suggest that patients who have recent exposure to vancomycin are at high risk for vancomycin failure and may benefit from an appropriate alternative when a diagnosis of MRSA HAP is made.
57 Million Americans Sickened by H1N1 Flu: CDC
With the H1N1 swine flu pandemic apparently winding down, federal health officials said Friday that about 57 million Americans have suffered through the illness since last April, and the total could range as high as 84 million. In addition, the U.S. Centers for Disease Control and Prevention (CDC) estimates that as many as 378,000 people were hospitalized due to H1N1 flu and up to 17,160 Americans may have died from the virus.
Oseltamivir Treatment Shortens Duration of Clinical Illness but not Viral Shedding in Household Transmission of Influenza Virus
Large clinical trials have demonstrated the therapeutic efficacy of oseltamivir against influenza. We assessed the indirect effectiveness of oseltamivir in reducing secondary household transmission in an incident cohort of influenza index patients and their household members.Index patients who took oseltamivir within 24 h of symptom onset halved the time to symptom alleviation. Oseltamivir treatment was not associated with statistically significant reduction in the duration of viral shedding. Household contacts of index patients who had taken oseltamivir within 24 h of onset had a nonstatistically significant lower risk of developing laboratory‐confirmed infection.
Vaccine-Autism Study Is Retracted
A major British medical journal on Tuesday retracted a flawed study linking the measles, mumps and rubella vaccine to autism and bowel disease. The retraction by The Lancet comes a day after a competing medical journal, BMJ, issued an embargoed commentary calling for The Lancet to formally retract the study. The commentary was to have been published on Wednesday.
Primary and booster immunization with a diphtheria, tetanus, acellular pertussis, hepatitis B (DTPa–HBV) and Haemophilus influenzae type b (Hib) vaccine administered separately or together is safe and immunogenic
A study out of the International Journal of Infectious Disease was conducted to evaluate the safety and immunogenicity of DTPa–HBV and Hib vaccines given mixed or separately to 360 healthy infants at 2, 4, and 6 months of age. One month after primary vaccination, 98% had seroprotective antibody levels against HBV and 94–97% against Hib (anti-PRP≥0.15μg/ml). One month after primary vaccination, 98% had seroprotective antibody levels against HBV and 94–97% against Hib (anti-PRP≥0.15μg/ml). After DTPa–HBV/Hib booster vaccination, 96–100% of subjects had seroprotective antibody concentrations against Hib, hepatitis B, tetanus, and diphtheria and high vaccine response rates against pertussis toxoid, filamentous hemagglutinin, and pertactin.
Escherichia coli Pyomyositis: An Emerging Infectious Disease among Patients with Hematologic Malignancies
Pyomyositis is typically caused by gram‐positive bacteria, especially Staphylococcus aureus. Few cases of Escherichia coli pyomyositis have been reported, including only 1 involving a patient with a hematologic malignancy.The clinical microbiology database at The M. D. Anderson Cancer Center (Houston, TX) was reviewed for the period January 2003 through December 2007 to identify cases of E. coli pyomyositis.Six cases of E. coli pyomyositis were identified. All patients were receiving chemotherapy for a hematologic malignancy; 5 were severely neutropenic. Three patients became hypotensive, 2 required intensive care, and 2 (33%) died, despite receiving carbapenem therapy.Awareness of this emerging syndrome and the usual causative agent is important to ensure appropriate management when febrile, neutropenic patients with hematologic malignancy exhibit signs of localized muscle infection.
Risk of Myocardial Infarction in Patients with HIV Infection Exposed to Specific Individual Antiretroviral Drugs from the 3 Major Drug Classes
The risk of myocardial infarction (MI) in patients with human immunodeficiency virus (HIV) infection has been assessed in 13 anti‐HIV drugs in the Data Collection on Adverse Events of Anti‐HIV Drugs (D:A:D) study. A meta analysis showed that over 178,835 person‐years, 580 patients developed MI. Recent exposure to abacavir or didanosine was associated with an increased risk of MI. No association was found between MI risk and cumulative exposure to nevirapine, efavirenz, nelfinavir, or saquinavir. Cumulative exposure to indinavir and lopinavir‐ritonavir was associated with an increased risk of MI. Of the drugs considered, only indinavir, lopinavir‐ritonavir, didanosine, and abacavir were associated with a significantly increased risk of MI.
