***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: A double-blind , r and omized study of inhaled zanamivir for the prevention of influenza in families was conducted . Once a person with a suspected case of influenza was identified ( index patient ) , treatment of all other household members ( contacts ) > or = 5 years old was initiated . Contacts received either 10 mg zanamivir or placebo inhaled once daily for 10 days . Index patients received relief medication only . In total , 487 households ( 242 placebo and 245 zanamivir ) were enrolled , with 1291 contacts r and omly assigned to receive prophylaxis . Four percent of zanamivir versus 19 % of placebo households ( P<.001 ) had at least 1 contact who developed symptomatic , laboratory-confirmed influenza , representing 81 % protective efficacy ( 95 % confidence interval , 64%-90 % ) . Protective efficacy was similarly high for individuals ( 82 % ) and against both influenza types A and B ( 78 % and 85 % , respectively , for households ) . Zanamivir was well tolerated and was effective in preventing influenza types A and B within households where the index patient was not treated BACKGROUND Influenza causes lower respiratory tract complications ( LRTCs ) , particularly bronchitis and pneumonia , in both otherwise healthy adults and those with underlying conditions . The aim of this study was to assess the effect of oseltamivir treatment on the incidence of LRTCs leading to antibiotic treatment and hospitalizations following influenza illness . METHODS We analyzed prospect ively collected data on LRTCs and antibiotic use from 3564 subjects ( age range , 13 - 97 years ) with influenzalike illness enrolled in 10 placebo-controlled , double-blind trials of oseltamivir treatment .  RESULTS In adults and adolescents with a proven influenza illness , oseltamivir treatment reduced overall antibiotic use for any reason by 26.7 % ( 14.0 % vs 19.1 % with placebo ; P<.001 ) and the incidence of influenza-related LRTCs result ing in antibiotic therapy by 55 % ( 4.6 % vs 10.3 % with placebo ; P<.001 ) . In those subjects considered at increased risk of complications , 74 ( 18.5 % ) of 401 placebo recipients developed an LRTC leading to antibiotic use compared with 45 ( 12.2 % ) of 368 oseltamivir recipients ( 34.0 % reduction ; P = .02 ) . Hospitalization for any cause occurred in 18 ( 1.7 % ) of 1063 placebo recipients compared with 9 ( 0.7 % ) of 1350 oseltamivir-treated patients ( 59 % reduction ; P = .02 ) . In contrast , among subjects with an influenzalike illness but without a confirmed influenza infection , the incidence of LRTCs ( 6.7 % vs 5.3 % ) , overall antibiotic use ( 19.7 % vs 19.3 % ) , or hospitalizations ( 1.7 % vs 1.9 % ) was similar between placebo and oseltamivir recipients , respectively . CONCLUSION Oseltamivir treatment of influenza illness reduces LRTCs , antibiotic use , and hospitalization in both healthy and " at-risk " adults We explored the prophylactic activity of zanamivir  after presumed exposure to influenza in the community . After close contacts with index cases of influenza-like illnesses , 575 subjects were r and omized in 4 treatment groups : 144 received placebo , 141 received intranasal zanamivir , 144 received inhaled zanamivir , and 146 received inhaled plus intranasal zanamivir for 5 days . Of 25 subjects ( 4 % ) who developed symptomatic influenza during the 5 days of prophylaxis , 9 ( 36 % ) were in the placebo group , 8 ( 32 % ) were in the intranasal zanamivir group ( odds ratio [ OR ] , 0.90 ; 95 % confidence interval [ CI ] , 0.30 - 2.72 ; P=.855 ) , 3 ( 12 % ) were in the inhaled zanamivir group ( OR , 0.27 ; 95 % CI , 0.07 - 1.05 ; P=.058 ) , and 5 ( 20 % ) were in the inhaled plus intranasal zanamivir group ( OR , 0.52 ; 95 % CI , 0.17 - 1.58 ; P=.247 ) . Short-term treatment with intranasal zanamivir was ineffective . However , inhaled zanamivir treatment reduced the rate of influenza , which was 2%-3 % among zanamivir recipients versus 6 % among placebo recipients . Additional studies assessing a longer duration of postcontact prophylaxis are warranted The antiviral and clinical effects of inhaled zanamivir ( 10 mg twice daily for 5 days , started within the first or second day of a flulike illness ) were evaluated in a r and omized ,  placebo-controlled trial during the 1997 - 1998 influenza season in Canada . Pharyngeal secretions were collected with swabs every 12 h during 6 days , and symptoms were self-evaluated twice daily during 14 days . After only 12 h of treatment ( 1 dose ) , median virus titers decreased by 1.0 log10 TCID50/mL in the  zanamivir group ( n=17 ) , compared with a 0 . 42-log10 increase in the placebo group ( n=10 ; P=.08 ) . This was associated with a 4.5-day ( 47.4 % ) reduction in the median time to alleviation of all significant flu symptoms in the  zanamivir recipients ( P=.03 after adjusting for the initial virus titer and the time between onset of symptoms and treatment ) . Resistance to zanamivir  was not detected in virus isolates by either phenotypic or genotypic assays The efficacy and safety of zanamivir , administered 2x or 4x daily over 5 days , was evaluated in the treatment of influenza infections . A total of 1256 patients entered the study ; 57 % of those r and omized had laboratory-confirmed influenza infection . The primary end point , " alleviation of major symptoms , " was created to evaluate differences in clinical impact . In the overall population with or without influenza infection , zanamivir reduced the median number of days to reach this end point by 1 day ( P=.012 2x daily vs. placebo ; P=.014 4x daily vs. placebo ) . The reduction was greater in patients treated within 30 h of symptom onset , febrile at study entry , and in defined high-risk groups . Zanamivir reduced nights of disturbed sleep , time to resumption of normal activities , and use of symptom relief medications . It was well tolerated . These results suggest that zanamivir can significantly reduce the duration and overall symptomatic effect of influenza We determined the efficacy of postexposure prophylaxis ( PEP ) and treatment of ill index cases with oseltamivir , in an attempt to prevent influenza transmission in households , in a study conducted in 277 households with 298 index cases ( 62 % with laboratory-confirmed influenza ) and 812 contacts aged > or = 1 year . Contacts were r and omized by household to receive treatment ( 5 days ; n=402 ) , if illness developed , or PEP for 10 days ( n=410 ) , and the number of households with at least 1 contact developing laboratory-confirmed influenza was measured . PEP provided a protective efficacy of 58.5 % ( 95 % confidence interval [ CI ] , 15.6%-79.6 % ; P=.0114 ) for households against proven influenza and 68.0 % ( 95 % CI , 34.9%-84.2 % ; P=.0017 ) for individual contacts , compared with treatment of index cases alone . No oseltamivir-resistant variants were detected in treated index cases or contacts . PEP of household contacts of those with influenza reduces the secondary spread of influenza in families when the initial household case is treated We have investigated the long-term prophylactic efficacy and safety of oseltamivir phosphate ( Ro64 - 0796 ) , an orally bioavailable prodrug of novel , potent and selective type A and type B influenzavirus neuraminidase inhibitor , when Ro64 - 0796 was administered orally to the healthy volunteers . Participants older than 16 year-old were r and omly assigned to either Ro64 - 0796 75 mg once daily group or matching placebo group for six weeks . A total of 308 participants ( Placebo group ; 153 and Ro64 - 0796 group ; 155 ) were enrolled in this trial . The primary variable of efficacy , incidence of laboratory-confirmed influenzavirus infected subjects accompanied by both fever of 37.5 degrees C or higher and at least two influenza symptoms ( group 1 ) were 1.3 % in Ro64 - 0796 group in contrast with 8.5 % in placebo group , inducing 85 % inhibition of infection ( p = 0.00323 , Fisher 's exact test ) . As secondary variable , incidence of laboratory-confirmed influenzavirus infected subjects who lack either fever ( 37.5 degrees C or higher ) or at least two influenza symptoms ( group 2 ) and incidence of asymptomatic infected subjects ( group 3 ) were tend to decrease in Ro64 - 0796 group , and finally cumulative inhibition rate was 76 % in group 1 + 2 combined ( p = 0.000891 . Fisher 's exact test ) , and 63 % in group 1 + 2 + 3 combined ( p = 0.002150 , Fisher 's exact test ) . As for the safety evaluations , Ro64 - 0796 was well tolerated but was associated with gastrointestinal disorders such as nausea and vomiting which were mild and allowable for the clinical use . There was no abnormal change attributable to Ro64 - 0796 application in the clinical laboratory tests as well as the physiological tests . Our results demonstrate that oseltamivir is safe and effective for the prevention of influenza OBJECTIVE To evaluate the efficacy and safety of oseltamivir phosphate as treatment for naturally acquired influenza infection . METHODS This study was conducted as a double-blind , r and omized , placebo-controlled , multicenter trial during the influenza epidemic season from January to April 2001 at 7 centers in China . A total of 478 adults without other medical history , aged 18 to 65 years , were enrolled into the study . All subjects demonstrated febrile respiratory illness of no more than 36 hours ' duration with a temperature of 37.8 degrees C or more plus at least two of the following symptoms : coryza/nasal congestion , sore throat , cough , myalgia/muscles aches and pain , fatigue , headache or chills/sweats . Individuals were r and omized into either the oseltamivir phosphate or placebo group with identical-looking capsules . Either oral oseltamivir phosphate , 75 mg twice daily , or placebo was administered to the subjects for 5 days . RESULTS A total of 451 individuals were analyzed for efficacy as the intent-to-treat population ( ITT ) ( 216 oseltamivir and 235 placebo ) and 273 individuals were identified as influenza-infected through laboratory test , who were then defined as the intent-to-treat infected population ( ITTI ) ( 134 oseltamivir and 139 placebo ) . Four hundred and fifty nine individuals were included in the safety analysis . In the ITTI population , the cumulative alleviation proportion of oseltamivir group was significantly higher than that of the placebo group ( P = 0.0466 ) ) . The median duration of illness was 91.6 h [ 95 % confidence interval ( CI ) = 80.2 - 101.3 h ] in the oseltamivir group and 95 h ( 95 % CI = 84.5 - 105.3 h ) in the placebo group . The median area under the curve of decreased total score was significantly higher in the oseltamivir group than in the placebo group , 1382.9 and 1236.7 score-hours , respectively ( P = 0.0196 ) . For the ITT population , similar results were observed . Adverse events ( AE ) were similarly reported in both the oseltamivir group and the placebo group . The main adverse events following test drug were gastrointestinal symptoms , neurological symptoms and rashes . CONCLUSION Oseltamivir was effective and well tolerated as treatment of early naturally acquired influenza CONTEXT Previous studies have shown oseltamivir , a neuraminidase inhibitor , to be effective in preventing influenza and treating experimental influenza . OBJECTIVE To evaluate the efficacy and safety of oseltamivir in the treatment of naturally acquired influenza infection . DESIGN R and omized , placebo-controlled , double-blind study conducted January through March 1998 . SETTING Sixty primary care and university health centers throughout the United States . PARTICIPANTS A total of 629 healthy nonimmunized adults aged 18 to 6 
    Output:
    
Neither NI has a significant effect on asymptomatic influenza .
Viral nasal titres were significantly diminished by both NIs .
We could find no comparative data on the effects of oseltamivir on avian influenza .