Neuraminidase inhibitors for preventing and treating influenza in children (published trials only)

A noninferiority randomized open-label pilot study of 3- versus 7-day influenza postexposure prophylaxis with oseltamivir in hospitalized children

Short influenza postexposure prophylaxis (PEP) showed high efficacy in adults, but studies in children are lacking. This randomized open-label pilot trial aimed to verify noninferiority of a 3- versus 7-day prophylaxis with oral oseltamivir in hospitalized children. Influenza contacts were randomized to the 3- or 7-day group and efficacy, relative risk of adverse events (AEs), and the cumulative costs of drugs and AEs management were compared. The intention-to-treat (ITT) analysis included 59 children (n = 28 and n = 31 in the 3- and 7-day group, respectively). The efficacy was 100% (95% CI 87.7-100%) versus 93.6% (95% CI 78.6-99.2%) in the 3- and 7-day group; the differences were statistically insignificant. A per-protocol (PP) analysis including 56 patients (n = 27 and n = 29, respectively) showed 100% (95% CI 87.2-100%) and 93.1% (95% CI 77.2-99.2%) efficacy, respectively, without statistical significance. Differences were within the predefined noninferiority margin with an efficacy difference Δ = 6.45 percentage points (p.p.) with 1-sided 95% CI (- 2.8, - 1.31, p = 0.86; ITT) and Δ = 6.9 p.p. (1-sided 95% CI - 2.83, - 1.27, p = 0.85; PP). Adverse events did not differ significantly, while the cumulative costs of the prophylaxis and AEs management were higher in the 7-day group (median 10.5 euro vs. 4.5 euro, p < 0.01). This pilot study showed the noninferiority of the 3-day versus 7-day PEP, which was associated with lower costs.Trial registration number: NCT04297462, 5th March 2020, restrospectively registered.

Influenza presentations and use of neuraminidase inhibitors by Australian general practice registrars: a cross-sectional analysis from the ReCEnT study

OBJECTIVE

This study aims to establish prevalence and associations of (1) influenza and influenza-like illness (IILI) presentations to Australian general practice (GP) registrars (trainees) and (2) the use of neuraminidase inhibitors (NAIs) by GP registrars for new presentations of IILI, for the 10 years leading up to the COVID-19 pandemic in Australia (2010-2019).

DESIGN

This was a cross-sectional analysis of the Registrar Clinical Encounters in Training ongoing inception cohort study of the in-consultation experience and clinical behaviours of GP registrars. Data are collected by individual registrars three times (from 60 consecutive consultations each time) at 6 monthly intervals. Data include diagnoses/problems managed and medicines prescribed, along with multiple other variables. Univariate and multivariable logistic regression was used to establish associations of registrars seeing patients with IILI and of prescribing NAIs for IILI.

SETTING

Teaching practices within the Australian general practitioner specialist vocational training programme. Practices were located in five of the six Australian states (plus one territory).

PARTICIPANTS

GP registrars in each of their three compulsory 6-month GP training terms.

RESULTS

From 2010 to 2019, 0.2% of diagnoses/problems seen by registrars were IILI. 15.4% of new IILI presentations were prescribed an NAI. IILI diagnoses were less likely in younger (0-14) and older (65+) age groups, and more likely in an area of higher socioeconomic advantage. There was considerable variation in NAI prescribing between regions. There was no significant association of prescribing NAIs with age or Aboriginal and/or Torres Strait Islander patients.

CONCLUSIONS

IILI presentations were more likely among working-age adults and not among those groups at higher risk. Similarly, high-risk patient groups who would benefit most were not more likely to receive NAIs. The epidemiology and management of IILI has been distorted by the COVID-19 pandemic, but the burden of influenza in vulnerable populations must not be overlooked. Appropriately targeted antiviral therapy with NAIs influences outcomes for vulnerable patients. General practitioners manage the majority of IILI in Australia, and understanding GP IILI presentation and NAI prescribing patterns is a key first step to enabling sound and rational prescribing decisions for better patient outcomes.

An overview of the characteristics and methodological standards across systematic reviews with Meta-analysis of efficacy/effectiveness of influenza antiviral drugs

BACKGROUND

Influenza antiviral drugs remain controversial and it is not clear if conclusions on their efficacy/effectiveness are based on high quality systematic reviews (SRs). We systematically identified, critically appraised, and summarized the characteristics and adherence to methodological standards in SRs with meta-analysis of efficacy/effectiveness of influenza antiviral drugs for prevention and/or treatment of influenza.

METHODS

We searched MEDLINE, Embase, Scopus, CINAHL, Global Health, and CDSR for English-language SR publications up to July 2020. We summarized the characteristics, adherence to methodological standards and SR quality (AMSTAR 2).

RESULTS

From a total 3,898 citations after removal of duplicates from all identified citations, we included 24 SRs. Seventy-five percent (n = 18) were of a critically low quality, 8% (n = 2) of a low quality, 17% (n = 4) of a moderate quality, and none were of a high quality. Seventeen percent (n = 4) were industry-funded, 4% (n = 1) coauthored by industry employee(s), and 33% (n = 8) commissioned by an organization or authority. Only 33% percent (n = 8) reported protocol registration, 4% (n = 1) reported collaboration with a knowledge synthesis librarian/information specialist, and 17% (n = 4) utilized a systematic review reporting checklist.

CONCLUSIONS

The evidence suggests that SRs of efficacy/effectiveness of influenza antiviral drugs are mostly of critically low quality and do not follow current best SR practices. These findings are significant in view of the important role of SRs in decision-making and the controversies that surround the use of the influenza antiviral drugs. However, the findings should not be interpreted to mean curtailment/cessation of use of antiviral drugs for influenza.

Evaluation of the Clinical Effectiveness of Oseltamivir for Influenza Treatment in Children

Objective: To estimate the clinical effectiveness of oseltamivir in children with different subtypes of influenza virus infection.

Methods: A total of 998 children with acute respiratory infection were enrolled from January to March 2018, and were divided into influenza A, influenza B, influenza A + B, and non-influenza infection (IV-negative) groups. Influenza-like symptoms and duration of fever were evaluated and compared between oseltamivir-treated and non-treated groups.

Results: There were no significant differences in the reduction in total febrile period and duration of fever from the onset of therapy between the oseltamivir treated and non-treated children infected with influenza A (p = 0.6885 for total febrile period and 0.7904 for the duration of fever from the onset of treatment), influenza B (p = 0.1462 and 0.1966), influenza A + B (p = 0.5568 and 0.9320), and IV-negative (p = 0.7631 and 0.4655). The duration of fever in children received oseltamivir therapy within 48 h was not significantly shorter than that beyond 48 h (p > 0.05). Additionally, percentages and severities of influenza-like symptoms, including headache, myalgia, fatigue, bellyache, vomiting, diarrhea, sore throat, cough, and coryza were not decreased and alleviated after treatment of oseltamivir.

Conclusion: Oseltamivir treatment does not significantly shorten the duration of fever, nor does it significantly relieve influenza-like symptoms in children with infection of influenza.

Pathophysiological effects of Tamiflu on liver and kidneys of male rats

BACKGROUND

Tamiflu/oseltamivir phosphate (OP), an anti-influenza drug, has a highly doubted safety especially after many cases of abnormal behaviour and deaths reported after being used. Such controversy was also locally and globally generated, especially after being heavily used in COVID-19 treatment protocol. This study was designed to evaluate the effect of three different doses of OP on the liver and kidneys of male adult albino rats through histological approaches, measuring their DNA integrity and biochemical analyses. Different doses of Tamiflu applied to humans were converted to rats, then observed their effects on the liver and kidneys. Rats were divided into four groups. G1: considered as control group. The rest of the three treated groups were received the same calculated dose of Tamiflu (6.75 mg/kg b.w.) in three different durations. G2, G3 and G4 represented the animals orally received OP, in which the rats received OP twice for 5 consecutive days, once for 10 and 45 days, respectively.

RESULTS

Our data showed numerous deleterious necrotic and fibrotic histopathological changes in the liver, and kidneys; as well as necrotic DNA smears, by using electrophoresis, in OP-treated rats of G2 and G4. In addition, OP significantly increased the serum cellular hepatic/renal toxicity markers (ALT, AST, ALP, GGT, indirect bilirubin, urea, creatinine, uric acid, & Na+). Also, it showed a reduction in the levels of serum total protein, albumin and K+ ions in rats of G2 and G4 compared with G1. In G3, OP treatment did not significantly alter hepatic/renal histological, DNA integrity and biochemical analyses in rats.

CONCLUSIONS

The therapeutic and long-term prophylactic doses of OP most likely cause structural and functional hepato- and nephrotoxicity in experimentally subjected rats. So, caution must be taken during Tamiflu treatment, and not used for long durations and/or with repetitive doses (time- and/or accumulative-dose-dependent); especially with patients suffer from liver and/or kidney dysfunction, while the short-term prophylactic dose of OP appears to be relatively safe and could be explored for oral medications.

GRAPHICAL ABSTRACT

Direct and Indirect Costs of Influenza-Like Illness Treated with and Without Oseltamivir in 15 European Countries: A Descriptive Analysis Alongside the Randomised Controlled ALIC4E Trial

Background and Objective

Influenza-like illness (ILI) leads to a substantial disease burden every winter in Europe; however, oseltamivir is not frequently prescribed to ILI patients in the primary-care setting. An open-label, multi-country, multi-season, randomised controlled trial investigated the effectiveness of oseltamivir for treating ILI in 15 European countries. We aimed to evaluate whether patients presenting with ILI in primary care and being managed with the addition of oseltamivir to usual care had lower average direct and indirect costs compared to patients with usual care alone.

Methods

Resource use data were extracted from participants’ daily diaries. Itemised country-specific unit costs were collected through official tariffs, pharmacies or literature. Costs were converted to 2018 values. The null hypothesis was tested based on one-sided credible intervals (CrIs) obtained by bootstrapping. Base-case analysis estimated direct cost and productivity losses using itemised costed resource use and the human capital approach. Scenario analyses with self-reported spending rather than itemised costing were also performed.

Results

Patients receiving oseltamivir (N = 1306) reported fewer healthcare visits, medication uses, hospital attendances and paid-work hours lost than the other patients (N = 1298). Excluding the oseltamivir cost, the average direct costs were lower in patients treated with oseltamivir from all perspectives, but these differences were not statistically significant (perspective of patient: €17 [0–95% Crl: 16–19] vs. €24 [5–100% Crl: 18–29]; healthcare provider: €37 [28–67] vs. €44 [25–55]; healthcare payers: €54 [45–85] vs. €68 [45–81]; and society: €423 [399–478] vs. €451 [390–478]). Scenario and age-group analyses confirmed these findings, but with some between-country differences.

Conclusion

The average direct and indirect costs were consistently lower in patients treated with oseltamivir than in patients without from four perspectives (excluding the oseltamivir cost). However, these differences were not statistically significant.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40261-021-01057-y.

[A network meta-analysis of the efficacy and safety of baloxavir marboxil versus neuraminidase inhibitors for the treatment of influenza in otherwise healthy patients]

AIM

Baloxavir marboxil (baloxavir) is the first cap-dependent endonuclease inhibitor being studied for the treatment of influenza in single oral dosing regimen. This network meta-analysis (NMA) evaluated the efficacy and safety of baloxavir compared to other antivirals for influenza in otherwise healthy patients.

METHODS

A systematic literature review was performed on 14 November 2016 in Medline, Embase, CENTRAL, and ICHUSHI to identify randomized controlled trials assessing antivirals for influenza. A NMA including 22 trials was performed to compare the efficacy and safety of baloxavir with other antivirals.

RESULTS

The time to alleviation of all symptoms was significantly shorter for baloxavir compared to zanamivir (difference in median time 19.96 h; 95% CrI [3.23, 39.07]). The time to cessation of viral shedding was significantly shorter for baloxavir than zanamivir and oseltamivir (47.00 h; 95% CrI [28.18, 73.86] and 56.03 h [33.74, 87.86], respectively). The mean decline in virus titer from baseline to 24 h was significantly greater for baloxavir than for the other drugs. Other differences in efficacy outcomes were not significant. No significant differences were found between baloxavir and the other antivirals for safety, except total drug-related adverse events where baloxavir demonstrated a decrease compared to oseltamivir and laninamivir.

CONCLUSION

The NMA suggests that baloxavir demonstrated better or similar efficacy results compared to other antivirals with a comparable safety profile. Baloxavir led to a significant decrease in viral titer versus zanamivir, oseltamivir and peramivir and decreased viral shedding versus zanamivir and oseltamivir.

Room Sharing in Hospitalized Children With Bronchiolitis and the Occurrence of Hospital-Acquired Infections: A Prospective Cohort Study

OBJECTIVES

To determine the prevalence and severity of hospital-acquired infections (HAIs) in children hospitalized for bronchiolitis when patients share a room, irrespective of the causative virus.

METHODS

A prospective cohort study during 4 winter seasons (2012-2016) was conducted in a Dutch general pediatric ward including otherwise healthy children <2 years of age hospitalized for bronchiolitis. Patients shared a 1-to-4-bed hospital room irrespective of virological diagnosis. The main outcome measures were HAIs assessed through multiplex polymerase chain reaction and disease severity.

RESULTS

HAIs occurred in 28 of 218 included patients (12.8%), most frequently with rhinovirus (17 of 28; 60.7%). In 3 (10.7%) of 28 HAIs, the same virus was identified in roommates. Only 1 patient became cross-infected with respiratory syncytial virus, although this patient never shared a room with a patient infected with respiratory syncytial virus. HAI was not associated with more severe disease. The median length of hospitalization was 3.5 days (interquartile range [IQR] 1-6) compared with 3 days (IQR 2-6; P = .86); the number of PICU admissions was 0% versus 5.3% (P = .21); the median days of oxygen supplementation was 2.5 (IQR 1-4) versus 2 (IQR 1-4; P = .58); the median days of tube feeding was 2 (IQR 0-5) versus 2 (interquartile range: 0-5; P = .77); and the readmission rate was 0% versus 5.8% (P = .19) in patients with and without HAI, respectively.

CONCLUSIONS

HAIs among patients with bronchiolitis are common but not associated with more severe disease. Room sharing with appropriate hygiene does not play a relevant role in the transmission of viruses between patients with bronchiolitis, regardless of the viruses involved. On the basis of these findings, we suggest that room sharing of patients with bronchiolitis is safe.

Drugs for Influenza Treatment: Is There Significant News?

Vaccines remain the best measure to reduce total influenza burden. However, presently available influenza vaccines have some limitations that cause a reduced efficacy compared to immunization practices with other respiratory pathogens. This paper shows the clinical roles of antiviral drugs against influenza that have been licensed in at least one country and the potential roles of compounds that are in development. Several attempts have been made to develop new agents against influenza viruses to overcome the supposed or demonstrated limitations of neuraminidase inhibitors (NAIs). Antibodies against the highly conserved stem region of the haemagglutinin molecule of influenza A viruses and drugs that target different stages of the influenza virus life cycle than NAIs in human cells have been developed and tested. Among these preparations, baloxavir marboxil (BAM), and favipiravir (FP) (i.e., polymerase inhibitors) are the only drugs that have reached the market (the first in Japan and the USA, and the second only in Japan). Other antiviral compounds and monoclonal antibodies are in advanced stage of development, but none of these new drugs and monoclonal antibodies in development have adequate characteristics to substitute for NAIs at present. However, although NAIs remain the drug of choice for influenza treatment, their overuse has to be avoided. Accurate selection of patients for whom treatment is truly needed is required.

The effect of neuraminidase inhibitors on household transmission in Japanese patients with influenza A and B infection: A prospective, observational study

Background

The relative ability of neuraminidase inhibitors (NAIs) to reduce household influenza transmission when given to index patients is not established.

Objectives

To compare daily secondary infection rates (SIR) of influenza A (A/H1pdm and A/H3) and B in households of index patients treated with oseltamivir, zanamivir, laninamivir, or peramivir.

Patients/Methods

This Japanese, single‐center, prospective, observational study (UMIN‐CTR: UMIN000024650) enrolled index patients with confirmed influenza who were treated with an NAI during 6 influenza seasons (2010‐2016). Secondary infection patients were household members diagnosed with the same influenza subtype 1‐7 days after onset in the index patient. Daily SIR was calculated using a modified Reed‐Frost model. The rate of household members with secondary infection and proportion of households with any secondary infection were also calculated.

Results

Index patients with influenza A (n = 1146) or B (n = 661) were enrolled (~3400 total index and secondary patients). Daily SIR for all virus subtypes was highest when oseltamivir was used (eg, unadjusted estimate: type A, 1.47% vs 0.71%‐1.13%; type B, 1.30% vs 0.59%‐0.88%). Pairwise comparisons revealed significant differences in daily SIR between NAIs for influenza type A, type B, and subtype A/H3; for example, for type A, SIR was significantly higher with oseltamivir than with peramivir or zanamivir. The rate of household members with secondary infection and proportion of households with any secondary infection also varied between NAIs.

Conclusions

Neuraminidase inhibitors differed in their ability to reduce household influenza transmission; transmission was highest with oseltamivir. Physicians may consider effects on household transmission when deciding which NAI to prescribe.

Advanced Prodrug Strategies in Nucleoside and Non-Nucleoside Antiviral Agents: A Review of the Recent Five Years

Background: Poor pharmacokinetic profiles and resistance are the main two drawbacks from which currently used antiviral agents suffer, thus make them excellent targets for research, especially in the presence of viral pandemics such as HIV and hepatitis C. Methods: The strategies employed in the studies covered in this review were sorted by the type of drug synthesized into ester prodrugs, targeted delivery prodrugs, macromolecular prodrugs, other nucleoside conjugates, and non-nucleoside drugs. Results: Utilizing the ester prodrug approach a novel isopropyl ester prodrug was found to be potent HIV integrase inhibitor. Further, employing the targeted delivery prodrug zanamivir and valine ester prodrug was made and shown a sole delivery of zanamivir. Additionally, VivaGel, a dendrimer macromolecular prodrug, was found to be very efficient and is now undergoing clinical trials. Conclusions: Of all the strategies employed (ester, targeted delivery, macromolecular, protides and nucleoside analogues, and non-nucleoside analogues prodrugs), the most promising are nucleoside analogues and macromolecular prodrugs. The macromolecular prodrug VivaGel works by two mechanisms: envelope mediated and receptor mediated disruption. Nucleotide analogues have witnessed productive era in the recent past few years. The era of non-interferon based treatment of hepatitis (through direct inhibitors of NS5A) has dawned.

Antiviral Medications in Seasonal and Pandemic Influenza

BACKGROUND

Amantadine, oseltamivir, and zanamivir are currently available in Germany for the prevention and treatment of influenza. We review their efficacy and side-effect profiles.

METHODS

This review is based on pertinent randomized and controlled trials (RCTs) and systematic reviews retrieved by a systematic literature search, and on other relevant literature.

RESULTS

The efficacy of antiviral drugs for the prevention of symptomatic influenza ranges from 60% to 90% (number needed to treat [NNT], 8-89) depending on the population and type of drug in question. Antiviral drugs shorten the duration of illness by 0.5-1.5 days when given within 48 hours of the onset of symptoms. Neuraminidase inhibitors do not significantly lower the incidence of bronchitis in adults, or of otitis media in children; they do have a positive effect against reported, but not necessarily diagnostically confirmed pneumonia in adults (NNT, 89 [50-232]). The RCTs yielded no information about possible effects on severe cases of influenza, or on mortality, as they included only mildly or moderately ill patients, but observational studies have yielded some evidence of benefit. The most common side effects of oseltamivir (>10%) are headache, nausea, and vomiting; of zanamivir (>1%), a skin rash; and of amantadine (>1%), loss of appetite, nausea, and central nervous effects.

CONCLUSION

The benefits of antiviral drugs, particularly neuraminidase inhibitors, outweigh their risks. In deciding whether to use them, physicians should consider the properties of the currently circulating viruses and the patient's individual risk constellation, as directed in clinical treatment recommendations.

Reducing disease burden in an influenza pandemic by targeted delivery of neuraminidase inhibitors: mathematical models in the Australian context

BACKGROUND

Many nations maintain stockpiles of neuraminidase inhibitor (NAI) antiviral agents for use in influenza pandemics to reduce transmission and mitigate the course of clinical infection. Pandemic preparedness plans include the use of these stockpiles to deliver proportionate responses, informed by emerging evidence of clinical impact. Recent uncertainty about the effectiveness of NAIs has prompted these nations to reconsider the role of NAIs in pandemic response, with implications for pandemic planning and for NAI stockpile size.

METHODS

We combined a dynamic model of influenza epidemiology with a model of the clinical care pathways in the Australian health care system to identify effective NAI strategies for reducing morbidity and mortality in pandemic events, and the stockpile requirements for these strategies. The models were informed by a 2015 assessment of NAI effectiveness against susceptibility, pathogenicity, and transmission of influenza.

RESULTS

Liberal distribution of NAIs for early treatment in outpatient settings yielded the greatest benefits in all of the considered scenarios. Restriction of community-based treatment to risk groups was effective in those groups, but failed to prevent the large proportion of cases arising from lower risk individuals who comprise the majority of the population.

CONCLUSIONS

These targeted strategies are only effective if they can be deployed within the constraints of existing health care infrastructure. This finding highlights the critical importance of identifying optimal models of care delivery for effective emergency health care response.

Uncomplicated pneumonia in healthy Canadian children and youth: Practice points for management

Although immunization has decreased the incidence of bacterial pneumonia in vaccinated children, pneumonia remains common in healthy children. Symptoms of bacterial pneumonia frequently overlap those present with viral infections or reactive airway disease. Optimally, the diagnosis of bacterial pneumonia should be supported by a chest radiograph before starting antimicrobials. Factors such as age, vital signs and other measures of illness severity are critical when deciding whether to admit a patient to hospital. Because Streptococcus pneumoniae continues to be the most common cause of bacterial pneumonia in children, prescribing amoxicillin or ampicillin for seven to 10 days remains the mainstay of empirical therapy for nonsevere pneumonia. If improvement does not occur, consideration should be given to searching for complications (empyema or lung abscess). Routine chest radiographs at the end of therapy are not recommended unless clinically indicated.

Review of Non-Bacterial Infections in Respiratory Medicine: Viral Pneumonia

Although bacteria are the main pathogens involved in community-acquired pneumonia, a significant number of community-acquired pneumonia are caused by viruses, either directly or as part of a co-infection. The clinical picture of these different pneumonias can be very similar, but viral infection is more common in the pediatric and geriatric populations, leukocytes are not generally elevated, fever is variable, and upper respiratory tract symptoms often occur; procalcitonin levels are not generally affected. For years, the diagnosis of viral pneumonia was based on cell culture and antigen detection, but since the introduction of polymerase chain reaction techniques in the clinical setting, identification of these pathogens has increased and new microorganisms such as human bocavirus have been discovered. In general, influenza virus type A and syncytial respiratory virus are still the main pathogens involved in this entity. However, in recent years, outbreaks of deadly coronavirus and zoonotic influenza virus have demonstrated the need for constant alert in the face of new emerging pathogens. Neuraminidase inhibitors for viral pneumonia have been shown to reduce transmission in cases of exposure and to improve the clinical progress of patients in intensive care; their use in common infections is not recommended. Ribavirin has been used in children with syncytial respiratory virus, and in immunosuppressed subjects. Apart from these drugs, no antiviral has been shown to be effective. Prevention with anti-influenza virus vaccination and with monoclonal antibodies, in the case of syncytial respiratory virus, may reduce the incidence of pneumonia.

Virus-induced secondary bacterial infection: a concise review

Respiratory diseases are a very common source of morbidity and mortality among children. Health care providers often face a dilemma when encountering a febrile infant or child with respiratory tract infection. The reason expressed by many clinicians is the trouble to confirm whether the fever is caused by a virus or a bacterium. The aim of this review is to update the current evidence on the virus-induced bacterial infection. We present several clinical as well in vitro studies that support the correlation between virus and secondary bacterial infections. In addition, we discuss the pathophysiology and prevention modes of the virus–bacterium coexistence. A search of the PubMed and MEDLINE databases was carried out for published articles covering bacterial infections associated with respiratory viruses. This review should provide clinicians with a comprehensive idea of the range of bacterial and viral coinfections or secondary infections that could present with viral respiratory illness.

The role of viral infection in pulmonary exacerbations of bronchiectasis in adults: a prospective study

BACKGROUND

Although viral infections are a major cause of exacerbations in patients with chronic airway diseases, their roles in triggering bronchiectasis exacerbations in adults remain unclear. Therefore, we prospectively investigated the incidence and clinical impacts of viral infection in adults with bronchiectasis exacerbations.

METHODS

The study cohort of 119 adults with bronchiectasis was followed up prospectively for 12 months. Nasopharyngeal swabs and sputum samples were assayed for 16 respiratory viruses, using polymerase chain reaction assays. Symptoms, spirometry, quality of life, bacterial cultures, and inflammatory markers were assessed during steady-state bronchiectasis and exacerbations.

RESULTS

A total of 100 exacerbations were captured from 58 patients during 1-year follow-up. Respiratory viruses were found more frequently in nasopharyngeal swabs and sputum during bronchiectasis exacerbations (49 of 100, 49.0') than during steady state (11 of 58, 18.9'; P < .001). The most common viruses found in patients experiencing exacerbations were coronavirus (19 of 65, 39.2'), rhinovirus (16 of 65, 24.6'), and influenza A/B viruses (16 of 65, 24.6'). Virus-positive exacerbations were associated with a greater increase in markers of systemic and airway inflammation (serum IL-6 and tumor necrosis factor-α; sputum IL-1β and tumor necrosis factor-α) compared with virus-negative exacerbations, but the differences in spirometric indexes, quality of life, and bacterial density were unremarkable. In receiver operating characteristics analysis, serum interferon-γ-induced protein 10 yielded an area under curve of 0.67 (95' CI, 0.53-0.77; P = .018). Furthermore, a greater proportion of patients with virus-positive exacerbations received IV antibiotics.

CONCLUSIONS

Prevalence of viral infections, detected by polymerase chain reaction assay, is higher in cases of bronchiectasis exacerbations than in steady-state bronchiectasis, suggesting that respiratory viruses play crucial roles in triggering bronchiectasis exacerbations. The potential mechanisms of virus-induced bronchiectasis exacerbations merit further investigations.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01801657; www.clinicaltrials.gov

Review of Non-Bacterial Infections in Respiratory Medicine: Viral Pneumonia

Although bacteria are the main pathogens involved in community-acquired pneumonia, a significant number of community-acquired pneumonia are caused by viruses, either directly or as part of a co-infection. The clinical picture of these different pneumonias can be very similar, but viral infection is more common in the pediatric and geriatric populations, leukocytes are not generally elevated, fever is variable, and upper respiratory tract symptoms often occur; procalcitonin levels are not generally affected. For years, the diagnosis of viral pneumonia was based on cell culture and antigen detection, but since the introduction of polymerase chain reaction techniques in the clinical setting, identification of these pathogens has increased and new microorganisms such as human bocavirus have been discovered. In general, influenza virus type A and syncytial respiratory virus are still the main pathogens involved in this entity. However, in recent years, outbreaks of deadly coronavirus and zoonotic influenza virus have demonstrated the need for constant alert in the face of new emerging pathogens. Neuraminidase inhibitors for viral pneumonia have been shown to reduce transmission in cases of exposure and to improve the clinical progress of patients in intensive care; their use in common infections is not recommended. Ribavirin has been used in children with syncytial respiratory virus, and in immunosuppressed subjects. Apart from these drugs, no antiviral has been shown to be effective. Prevention with anti-influenza virus vaccination and with monoclonal antibodies, in the case of syncytial respiratory virus, may reduce the incidence of pneumonia.

In-silico structural analysis of the influenza A subtype H7N9 neuraminidase and molecular docking with different neuraminidase inhibitors

Human infection with H7 influenza subtypes usually resulted in mild disease with a rare mortalities, however, human infection with the avian low pathogenic H7N9 influenza virus resulted in about 38.6 % human fatality. Due to the new cross-species barrier of this virus subtype, there is an urgent need to better understand the susceptibility to commercially available antivirals and their relation to the structural changes of the viral neuraminidase. Neuraminidases derived from 2013 H7N9, H5N1 and H1N1 were subjected to a structural analysis of their catalytic and framework binding sites. The modeling structure of selected neuraminidases from H7N9 and influenza A subtypes were solved and the docking studies with oseltamivir, zanamivir, laninamivir and peramivir were conducted. The active site residues that are responsible for both binding and cleavage of the terminally linked sialic acid receptors were found conserved. Docking studies with oseltamivir, zanamivir, laninamivir and peramivir revealed that the laninamivir and peramivir showed superior energy binding activities in comparison to the commonly used oseltamivir and zanamivir. The results presented in the current study provide data that are useful for the future treatment of different influenza A subtypes including the recently emerged H7N9.

A prospective observational study of oseltamivir safety and tolerability in infants and young children ≤24 months

PURPOSE

Infants and young children are at elevated risk of influenza-associated complications, but information on the safety of antiviral therapies is limited in this age group.

METHODS

In this prospective open-label observational safety study, children aged ≤24 months with a clinical diagnosis of influenza in routine practice received either no antiviral treatment ('unexposed' group) or oseltamivir treatment or prophylaxis ('exposed' group), according to the physician's judgment. Patients were followed up for 30 days after the baseline visit.

RESULTS

Adverse events (AEs) were analysed in 1065 patients; they were reported in 390/711 (54.9%) in the unexposed group, 167/340 (49.1%) patients in the exposed group, and 6/14 prophylaxis patients. Cough and rhinitis were the most common events, reported more often in unexposed children (22.9 and 20.3% respectively) than in exposed children (13.2 and 10.0%; p < 0.001); pyrexia, diarrhoea and vomiting were less common, occurring at similar rates in exposed and unexposed patients. Nasal congestion (3.5%), bronchitis (5.6%) and upper respiratory tract infection (1.5%) were reported more frequently in exposed patients than in unexposed patients (0.7, 2.7 and 0.1% respectively; p < 0.05). In the exposed group, 11.2% of patients (n = 38) experienced 41 AEs considered at least possibly related to oseltamivir, none being assessed as serious. Overall, there were 79 serious AEs in 59 patients. Eleven discontinued treatment because of an AE.

CONCLUSIONS

Oseltamivir has a good tolerability profile in infants and children aged ≤24 months. These findings contributed to the recent FDA approval of oseltamivir for treating infants aged 2-51 weeks.

Risk of bias in industry-funded oseltamivir trials: comparison of core reports versus full clinical study reports

BACKGROUND

The Cochrane risk of bias tool is a prominent instrument used to evaluate potential biases in clinical trials. In three updates of our Cochrane review on neuraminidase inhibitors, we assessed risk of bias on the same trials using different levels of detail: the trials in journal publications, in core reports, and in full clinical study reports. Here we analyse whether progressively greater amounts of information and detail in full clinical study reports (including trial protocols, statistical analysis plans, certificates of analyses, individual participant data listings and randomisation lists) affected our risk of bias assessments.

METHODS AND FINDINGS

We used the Cochrane risk of bias tool to assess and compare risk of bias in 14 oseltamivir trials (reported in 10 clinical study reports) obtained from the European Medicines Agency (EMA) and the manufacturer, Roche. With more detailed information, reported in clinical study reports, no previous assessment of 'high' risk of bias was reclassified as 'low' or 'unclear' in the main analysis, and over half (55%, 34/62) of the previous assessments of 'low' risk of bias were reclassified as 'high'. Most assessments of 'unclear' risk of bias (67%, or 28/42) were reclassified as 'high' risk of bias when our judgements were based on full clinical study reports. The limits of our study were our relative inexperience in dealing with large information sets, sometimes subjective bias judgements and focus on industry trials. Comparison with journal publications was not possible because of the low number of trials published.

CONCLUSIONS

We found that as information increased in the document, this increased our assessment of bias. This may mean that risk of bias has been insufficiently assessed in Cochrane reviews based on journal publications.

Effect of nitazoxanide in adults and adolescents with acute uncomplicated influenza: a double-blind, randomised, placebo-controlled, phase 2b/3 trial

Background

Influenza is an important cause of morbidity and mortality worldwide. Treatment options are scarce, and new drugs with novel mechanisms of action are needed. We aimed to assess the efficacy and safety of nitazoxanide, a thiazolide anti-infective, for treatment of acute uncomplicated influenza.

Methods

We did a double-blind, randomised, placebo-controlled, phase 2b/3 trial in 74 primary care clinics in the USA between Dec 27, 2010, and April 30, 2011. We enrolled participants aged 12–65 years with fever, at least one respiratory symptom, and one constitutional symptom of influenza within 48 h of symptom onset. We randomly assigned participants to receive either nitazoxanide 600 mg, nitazoxanide 300 mg, or placebo twice daily for 5 days, (ratio 1:1:1) and followed them up for 28 days. Randomisation lists were computer generated and done in blocks of three. Sponsor, investigators, study monitors, patients, and laboratory personnel were all masked to treatment allocation in the study. The primary endpoint was the time from first dose to alleviation of symptoms. The primary analysis was by intention-to-treat for participants with influenza infection confirmed by RT-PCR or culture at baseline. This trial is registered with ClinicalTrials.gov, number NCT01227421.

Findings

Of 650 participants screened, 624 (96%) were enrolled. Of these, 212 were randomly assigned to receive placebo twice a day, 201 to receive nitazoxanide 300 mg twice a day, and 211 to receive nitazoxanide 600 mg a day. The median duration of symptoms for participants receiving placebo was 116·7 h (95% CI 108·1–122·1) compared with 95·5 h (84·0–108·0; p=0·0084) for those receiving 600 mg nitazoxanide and 109·1 h (96·1–129·5, p=0·52) for those receiving 300 mg nitazoxanide. Adverse events were similar between the three groups, the most common being headache reported by 24 (11%) of 212 patients enrolled in placebo group, 12 (6%) of 201 patients in the low-dose group, and 17 (8%) of 211 patients in the high-dose group, or diarrhoea, reported by seven (3%) patients in the placebo group, four (2%) patients enrolled in the low-dose group, and 17 (8%) patients in the high-dose group.

Interpretation

Treatment with nitazoxanide 600 mg twice daily for 5 days was associated with a reduction of the duration of symptoms in participants with acute uncomplicated influenza. Further studies are warranted to confirm these findings and to assess efficacy of the drug alone or in combination with existing drugs in seriously ill patients and those at risk of influenza complications.

Funding

Romark Laboratories LC.

Zanamivir for influenza in adults and children: systematic review of clinical study reports and summary of regulatory comments

OBJECTIVES

To describe the potential benefits and harms of zanamivir.

DESIGN

Systematic review of clinical study reports of randomised placebo controlled trials and regulatory information

DATA SOURCES

Clinical study reports, trial registries, electronic databases, regulatory archives, and correspondence with manufacturers.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised placebo controlled trials in adults and children who had confirmed or suspected exposure to natural influenza.

MAIN OUTCOME MEASURES

Time to first alleviation of symptoms, influenza outcomes and complications, admissions to hospital, and adverse events in the intention to treat (ITT) population.

RESULTS

We included 28 trials in stage 1 (judgment of appropriate study design) and 26 in stage 2 (formal analysis). For treatment of adults, zanamivir reduced the time to first alleviation of symptoms of influenza-like illness by 0.60 days (95% confidence interval 0.39 to 0.81, P<0.001, I(2)=9%), which equates to an average 14.4 hours' reduction, or a 10% reduction in mean duration of symptoms from 6.6 days to 6.0 days. Time to first alleviation of symptoms was shorter in all participants when any relief drugs were allowed compared with no use. Zanamivir did not reduce the risk of self reported investigator mediated pneumonia (risk difference 0.17%, -0.73% to 0.70%) or radiologically confirmed pneumonia (-0.06%, -6.56% to 2.11%) in adults. The effect on pneumonia in children was also not significant (0.56%, -1.64% to 1.04%). There was no significant effect on otitis media or sinusitis in both adults and children, with only a small effect noted for bronchitis in adults (1.80%, 0.65% to 2.80%), but not in children. There were no data to assess effects on admissions in adults and children. Zanamivir tended to be well tolerated. In zanamivir prophylaxis studies, symptomatic influenza in individuals was significantly reduced (1.98%, (0.98% to 2.54%); reducing event rates from 3.26% to 1.27%, which means 51 people need to be treated to prevent one influenza case (95% confidence interval, 40 to 103). In contrast, the prophylaxis effect on asymptomatic influenza cases was not significant in individuals (risk difference 0.14%, -1.10% to 1.10%) or in households (1.32%, -2.20% to 3.84%). In households treated prophylactically there was an effect on symptomatic influenza (14.84%, 12.18% to 16.55%), but this was based on only two small studies including 824 participants. Prophylaxis in adults reduced unverified pneumonia (0.32%, 0.09% to 0.41%; NNTB (number needed to treat to benefit) 311, 244 to 1086) but had no effect on pneumonia in children or on bronchitis or sinusitis in adults or children (risk difference 0.32%, 0.09% to 0.41%; NNTB 311, 244 to 1086).

CONCLUSIONS

Based on a full assessment of all trials conducted, zanamivir reduces the time to symptomatic improvement in adults (but not in children) with influenza-like illness by just over half a day, although this effect might be attenuated by symptom relief medication. Zanamivir also reduces the proportion of patients with laboratory confirmed symptomatic influenza. We found no evidence that zanamivir reduces the risk of complications of influenza, particularly pneumonia, or the risk of hospital admission or death. Its harmful effects were minor (except for bronchospasm), perhaps because of low bioavailability.

Mucosal immune responses predict clinical outcomes during influenza infection independently of age and viral load

RATIONALE

Children are an at-risk population for developing complications following influenza infection, but immunologic correlates of disease severity are not understood. We hypothesized that innate cellular immune responses at the site of infection would correlate with disease outcome.

OBJECTIVES

To test the immunologic basis of severe illness during natural influenza virus infection of children and adults at the site of infection.

METHODS

An observational cohort study with longitudinal sampling of peripheral and mucosal sites in 84 naturally influenza-infected individuals, including infants. Cellular responses, viral loads, and cytokines were quantified from nasal lavages and blood, and correlated to clinical severity.

MEASUREMENTS AND MAIN RESULTS

We show for the first time that although viral loads in children and adults were similar, innate responses in the airways were stronger in children and varied considerably between plasma and site of infection. Adjusting for age and viral load, an innate immune profile characterized by increased nasal lavage monocyte chemotactic protein-3, IFN-α2, and plasma IL-10 levels at enrollment predicted progression to severe disease. Increased plasma IL-10, monocyte chemotactic protein-3, and IL-6 levels predicted hospitalization. This inflammatory cytokine production correlated significantly with monocyte localization from the blood to the site of infection, with conventional monocytes positively correlating with inflammation. Increased frequencies of CD14(lo) monocytes were in the airways of participants with lower inflammatory cytokine levels.

CONCLUSIONS

An innate profile was identified that correlated with disease progression independent of viral dynamics and age. The airways and blood displayed dramatically different immune profiles emphasizing the importance of cellular migration and localized immune phenotypes.

The common cold: potential for future prevention or cure

The common cold is the most frequent, although generally mild, human disease. Human Rhinoviruses are the prevalent causative agents, but other viruses are also implicated. Being so common, viral colds, have significant implications on public health and quality of life, but may also be life-threatening for vulnerable groups of patients. Specific diagnosis and treatment of the common cold still remain unmet needs. Molecular diagnostic techniques allow specific detection of known pathogens as well as the identification of newly emerging viruses. Although a number of medications or natural treatments have been shown to have some effect, either on the number or on the severity of common colds, no single agent is considerably effective. Virus-specific management remains in most cases a challenging potential as many factors have to be taken into account, including the diversity of the viral genomes, the heterogeneity of affected individuals, as well as the complexity of this long standing host-virus relationship.

The burden of seasonal and pandemic influenza in infants and children

The burden of influenza is unevenly distributed, with more severe outcomes in children aged <5 years than older children and adults. In spite of this, immunisation policies for young children are far from universal. This article provides an overview of the published evidence on the burden of influenza in children worldwide, with a particular interest in the impact of pandemic influenza in 2009-2010 (caused by the H1N1pdm09 virus). In an average season, up to 9.8 % of 0- to 14-year olds present with influenza, but incidence rates can be markedly higher in younger children. Children aged <5 years have greater rates of hospitalisation and complications than their older counterparts, particularly if the children have co-existing illnesses; historically, this age group have had higher mortality rates from the disease than other children, although during the 2009-2010 pandemic the median age of those who died of influenza was higher than in previous seasons. Admissions to hospital and emergency departments appear to have been more frequent in children with H1N1pdm09 infections than during previous seasonal epidemics, with pneumonia continuing to be a common complication in this setting. Outcomes in children hospitalised with severe disease also seem to have been worse for those infected with H1N1pdm09 viruses compared with seasonal viruses. Studies in children confirm that vaccination reduces the incidence of seasonal influenza and the associated burden, underlining the importance of targeting this group in national immunisation policies.

CONCLUSIONS

Children aged <5 years are especially vulnerable to influenza, particularly that caused by seasonal viruses, and vaccination in this group can be an effective strategy for reducing disease burden.

Neuraminidase inhibitors for influenza B virus infection: efficacy and resistance

Many aspects of the biology and epidemiology of influenza B viruses are far less studied than for influenza A viruses, and one of these aspects is efficacy and resistance to the clinically available antiviral drugs, the neuraminidase (NA) inhibitors (NAIs). Acute respiratory infections are one of the leading causes of death in children and adults, and influenza is among the few respiratory infections that can be prevented and treated by vaccination and antiviral treatment. Recent data has suggested that influenza B virus infections are of specific concern to pediatric patients because of the increased risk of severe disease. Treatment of influenza B is a challenging task for the following reasons: This review presents current knowledge of the efficacy of NAIs for influenza B virus and antiviral resistance in clinical, surveillance, and experimental studies.

Prevention of influenza in healthy children

Healthy children are high transmitters of influenza and can experience poor influenza outcomes. Many questions remain about the efficacy and impect of preventive measures because most existing studies report imprecise proxies of influenza incidence, do not follow subjects throughout the entire influenza season and across multiple influenza seasons, or do not control for important factors such as timing of implementation and social contact patterns. Modeling and simulation are key methodologies to answer questions regarding influenza prevention. While vaccination may be the most efficacious existing intervention, variations in circulating strains and children's immune systems keep current vaccines from being fully protective, necessitating further clinical and economic studies and technology improvements. Hand hygiene appears to be an important adjunct but improving compliance, standardizing regimens and quantifying its impact remain challenging. Future studies should help better define the specific indications and circumstances for antiviral use and the role of nutritional supplements and nonpharmaceutical interventions.

Influenza vaccines and vaccinations in Poland - past, present and future

Influenza causes seasonal infections worldwide that can lead to complications and deaths in every age group. The most effective and cheapest way to combat influenza is through vaccination. In many countries, including Poland, for each age group, the rate of vaccination against influenza is still at a very low level, which generates high social costs, not infrequently family tragedies in the case of irreversible complications of influenza, or death of a loved one. Regular vaccination should be part of good medical practice, as well as an individual’s engagement in their own health and in that of their family. Based on numerous studies, it is estimated that the effectiveness of current inactivated influenza vaccine in reducing morbidity and mortality in high-risk groups ranges from 50–70%. According to data from the National Institute of Public Health-National Institute of Hygiene, the rate of vaccination in children in 2008 in Poland was very low. In the group of children aged from 6 months to 14 years, only 1.1–1.6% were vaccinated. Although influenza vaccination for people aged over 65 years was free of charge in many provinces in this group, only 13.4% of this population was immunized, while in the case of people with chronic diseases, only 11.1% were immunized. The vaccination rate among health care employees is an embarrassing 6.4%. More educational activities addressed to both medical professionals and patients are required in order to increase influenza vaccine coverage in Poland.

The value of neuraminidase inhibitors for the prevention and treatment of seasonal influenza: a systematic review of systematic reviews

Controversy has arisen regarding the effectiveness of neuraminidase inhibitors (NIs), especially against influenza-related complications. A literature search was performed to critically assess the evidence collected by the available systematic reviews (SRs) regarding the benefits and disadvantages of NIs (oseltamivir, zanamivir) compared to placebos in healthy and at-risk individuals of all ages for prophylaxis and treatment of seasonal influenza. A SR was done using the Cochrane Database of Systematic Reviews, Health Technology Assessment Database, Database of Abstracts of Reviews of Effects, and Medline (January 2006-July 2012). Two reviewers selected SRs based on randomized clinical trials, which were restricted to intention-to-treat results, and they assessed review (AMSTAR) and study quality indicators (GRADE). The SRs included (N = 9) were of high quality. The efficacy of NIs in prophylaxis ranged from 64% (16-85) to 92% (37-99); the absolute risk reduction ranged from 1.2% to 12.1% (GRADE moderate to low). Clinically relevant treatment benefits of NIs were small in healthy adults and children suffering from influenza-like illness (GRADE high to moderate). Oseltamivir reduced antibiotic usage in healthy adults according to one SR, but this was not confirmed by other reviews (GRADE low). Zanamivir showed a preventive effect on antibiotic usage in children (95% (77-99);GRADE moderate) and on the occurrence of bronchitis in at-risk individuals (59% (30-76);GRADE moderate). No evidence was available on the treatment benefits of NIs in elderly and at-risk groups and their effects on hospitalization and mortality. In oseltamivir trials, nausea, vomiting and diarrhea were significant side-effects. For zanamivir trials, no adverse effects have been reported. The combination of diagnostic uncertainty, the risk for virus strain resistance, possible side effects and financial cost outweigh the small benefits of oseltamivir or zanamivir for the prophylaxis and treatment of healthy individuals. No relevant benefits of these NIs on complications in at-risk individuals have been established.

Chinese medicinal herbs for influenza

BACKGROUND

Influenza is a communicable acute respiratory infection which, during epidemics, can cause high morbidity and mortality rates. Traditional Chinese medicinal herbs, often administered following a particular Chinese medical theory, may be a potential treatment of choice.

OBJECTIVES

To assess the effect of Chinese medicinal herbs used to prevent and treat influenza and to estimate the frequency of adverse effects.

SEARCH METHODS

We searched CENTRAL (2012, Issue 11), MEDLINE (January 1966 to November week 2, 2012), EMBASE (January 1988 to November 2012) and CNKI (January 1988 to 29 March 2012). We also searched reference lists of articles and the WHO ICTRP search portal (November 2012).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing traditional Chinese medicinal herbs with placebo, no treatment or conventional medicine normally used in preventing and treating uncomplicated influenza.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed trial quality.

MAIN RESULTS

We included 18 studies involving 2521 participants. The methodological quality of 17 included studies was poor. Included RCTs separately compared medicinal herbs with different antiviral drugs, precluding any pooling of results. Only three indicated that compared with antiviral drugs, Chinese medicinal herbs may be effective in preventing influenza and alleviating influenza symptoms. 'Ganmao' capsules were found to be more effective than amantadine in decreasing influenza symptoms and speeding recovery in one study (in which adverse reactions were mentioned in the amantadine group although no data were reported). There were no significant differences between 'E Shu You' and ribavirin in treating influenza, nor in the occurrence of adverse reactions. Ten studies reported mild adverse reactions.

AUTHORS' CONCLUSIONS

Most Chinese medical herbs in the included studies showed similar effects to antiviral drugs in preventing or treating influenza. Few were shown to be superior to antiviral drugs. No obvious adverse events were reported in the included studies. However, current evidence remains weak due to methodological limitations of the trials. More high-quality RCTs with larger numbers of participants and clear reporting are needed.

Protecting pediatric oncology patients from influenza

Influenza is a common respiratory pathogen. Its severity can be unpredictable, but people with chronic illness are at increased risk of severe infection, complications, and death from influenza. This review examines evidence to support various strategies to protect pediatric oncology patients from influenza-related morbidity. Influenza vaccination should be considered standard. Additional evidence-supported measures include antiviral treatment, antiviral prophylaxis, cohorting of patients, and hospital infection control measures. Data from other high-risk populations support the vaccination of family members, double-dose or high-dose vaccination, and the use of barrier methods. These measures have the potential to optimize patient outcomes because there will be fewer treatment interruptions for acute illness. These strategies can also protect patients from prolonged hospitalizations and morbidity related to influenza.

Homeopathic Oscillococcinum(®) for preventing and treating influenza and influenza-like illness

BACKGROUND

Influenza is a highly infectious viral disease that is particularly common in the winter months. Oscillococcinum(®) is a patented homeopathic medicine that is made from a 1% solution of wild duck heart and liver extract, which is then serially diluted 200 times with water and alcohol.

OBJECTIVES

To determine whether homeopathic Oscillococcinum(®) is more effective than placebo in the prevention and/or treatment of influenza and influenza-like illness in adults or children.

SEARCH METHODS

We searched CENTRAL (2012, Issue 7), MEDLINE (1966 to July week 4, 2012), MEDLINE In-Process & Other Non-Indexed Citations (6 August 2012), AMED (2006 to August 2012), Web of Science (1985 to August 2012), LILACS (1985 to August 2012) and EMBASE (1980 to August 2012). We contacted the manufacturers of Oscillococcinum(®) for information of more trials.

SELECTION CRITERIA

Randomised, placebo-controlled trials of Oscillococcinum(®) in the prevention and/or treatment of influenza and influenza-like illness in adults or children.

DATA COLLECTION AND ANALYSIS

Three review authors independently extracted data and assessed risk of bias in the eligible trials.

MAIN RESULTS

We included six studies: two prophylaxis trials (327 young to middle-aged adults in Russia) and four treatment trials (1196 teenagers and adults in France and Germany). The overall standard of trial reporting was poor and hence many important methodological aspects of the trials had unclear risk of bias. There was no statistically significant difference between the effects of Oscillococcinum(®) and placebo in the prevention of influenza-like illness: risk ratio (RR) 0.48, 95% confidence interval (CI) 0.17 to 1.34, P = 0.16. Two treatment trials (judged as 'low quality') reported sufficient information to allow full data extraction: 48 hours after commencing treatment, there was an absolute risk reduction of 7.7% in the frequency of symptom relief with Oscillococcinum(®) compared with that of placebo (risk difference (RD) 0.077; 95% CI 0.03 to 0.12); the RR was 1.86 (95% CI 1.27 to 2.73; P = 0.001). A significant but lesser effect was observed at three days (RR 1.27, 95% CI 1.03 to 1.56; P = 0.03), and no significant difference between the groups was noted at four days (RR 1.11, 95% CI 0.98 to 1.27; P = 0.10) or at five days (RR 1.06; 95% CI 0.96 to 1.16; P = 0.25). One of the six studies reported one patient who suffered an adverse effect (headache) from taking Oscillococcinum(®).

AUTHORS' CONCLUSIONS

There is insufficient good evidence to enable robust conclusions to be made about Oscillococcinum(®) in the prevention or treatment of influenza and influenza-like illness. Our findings do not rule out the possibility that Oscillococcinum(®) could have a clinically useful treatment effect but, given the low quality of the eligible studies, the evidence is not compelling. There was no evidence of clinically important harms due to Oscillococcinum(®).