human
***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: Rotavirus ( RV ) infection is the primary cause for childhood gastroenteritis worldwide . In Korea , RV infection is most common among children less than 5 y of age . This post-licensure study was conducted to further evaluate the RV vaccine ( RIX4414 ) to provide additional local clinical data to the Korean Food and Drug Association . Healthy infants aged 6–12 weeks were enrolled to receive two doses of either RIX4414 or placebo as per 0 , 1–2 mo schedule . Blood sample s were collected before dose-1 and one month post-dose-2 of RIX4414/placebo to assess serum anti-RV IgA antibody concentrations using ELISA . Gastroenteritis stool sample s were tested for the presence of RV using ELISA . RV positive sample s were subjected to further analysis for G and P typing . Among 684 infants enrolled and vaccinated , 432 infants ( RIX4414 = 318 ; placebo = 114 ) were included in the according-to- protocol cohort for immunogenicity . The anti-RV IgA antibody seroconversion rates in the RIX4414 group following one month post-dose-2 were 88.1 % ( 95 % CI : 84.0–91.4 ) and the corresponding geometric mean concentration in the RIX4414 group was 208.5 U/ml ( 95 % CI : 174.2–249.5 ) . Occurrence of solicited and unsolicited adverse events were similar in both , RIX4414 and placebo groups . None of the gastroenteritis stool sample s tested positive for RV and no fatal SAEs were reported in either groups . The two-dose regimen of RIX4414 was observed to be immunogenic with a similar safety profile as compared with the placebo group , when administered to healthy Korean infants Objective . Revaccination policies adopted in many countries to control measles have raised various safety issues including those concerning the second vaccine dose . We performed a prospect i ve , double-blind , crossover trial among twins receiving a measles-mumps-rubella ( MMR ) vaccine .  Study Design . The study comprised 1162 monozygous and heterozygous twins , each of whom r and omly received placebo and then vaccine , or vice versa , 3 weeks apart , at 14 to 83 months of age . Most of the oldest children had previously been vaccinated against measles , and one half of the remainder of children had had the disease . Symptoms and signs were recorded daily on structured forms . Statistical methods included a complex analysis of the vaccine attributability of the symptoms and conditional logistic regression . Results . Vaccination-attributable events occurred in 6 % overall . At 14 to 18 months of age , reactions developed between days 6 and 14 , peaking at day 10 . The clearest vaccine-attributable effect was fever exceeding 101.3 ° F ( 38.5 ° C ; odds ratio : 3.28 ; 95 % confidence interval : 2.23–4.82 ; P < .001 ) , but the same trend was found for rash , arthralgia , conjunctivitis , staying in bed , drowsiness , and irritability . At 6 years of age , systemic reactions occurred 5 to 15 times less frequently , only arthralgia being associated with vaccination . Zygocity , gender , history of allergy , or infections did not modify reactions . Instead , respiratory symptoms developed within days postinjection to a level of 15 % to 20 % without subsequent decline and with no difference between vaccinees and placebo recipients . Conclusion . Vaccination was avoided during infections , but many small children became mildly ill within a week or so with no relation to vaccination ( the healthy vaccinee effect ) . MMR vaccine was virtually nonreactogenic when given at 6 years of age . vaccine , measles , mumps , rubella , reactogenicity , adverse events , zygocity , healthy vaccinee effect The vast majority of adverse reactions following immunisation of children with live measles-mumps-rubella ( MMR ) vaccine  were shown in a double-blind , placebo-controlled , cross-over study in 581 twin pairs to be only temporally but not causally related to the vaccination . The true frequency of side-effects caused by MMR vaccine , estimated from the discordance rates of individual signs and symptoms between MMR vaccinees and their placebo-injected twins , was between 0.5 and 4.0 % . Moreover , respiratory symptoms , nausea , and vomiting were observed more frequently in the placebo-injected group than in the MMR vaccinated group Summary Previous studies have suggested that infant vaccinations may reduce the risk of subsequent childhood leukaemia .  Vaccination histories were compared in 439 children ( ages 0–14 ) diagnosed with acute lymphoblastic leukaemia ( ALL ) in nine Midwestern and Mid-Atlantic states ( USA ) between 1 January 1989 and 30 June 1993 and 439 controls selected by r and om-digit dialing and individually matched to cases on age , race and telephone exchange . Among matched pairs , similar proportions of cases and controls had received at least one dose of oral poliovirus ( 98 % ) , diphtheria – tetanus – pertussis ( 97 % ) , and measles – mumps – rubella ( 90 % ) vaccines . Only 47 % of cases and 53 % of controls had received any  Haemophilus influenzae type b ( Hib ) vaccine  ( relative risk ( RR ) = 0.73 ; 95 % confidence interval ( CI ) 0.50–1.06 ) . Although similar proportions of cases ( 12 % ) and controls ( 11 % ) received the polysaccharide Hib vaccine ( RR = 1.13 ; 95 % CI 0.64–1.98 ) , more controls ( 41 % ) than cases ( 35 % ) received the conjugate Hib vaccine ( RR = 0.57 ; 95 % CI 0.36–0.89 ) . Although we found no relationship between most infant vaccinations and subsequent risk of childhood ALL , our findings suggest that infants receiving the conjugate Hib vaccine may be at reduced risk of subsequent childhood acute lymphoblastic leukemia . Further studies are needed to confirm this association and , if confirmed , to eluci date the underlying mechanism BACKGROUND Rotavirus is the most common cause of severe gastroenteritis among young children worldwide . Data are needed to assess the efficacy of the rotavirus vaccine in African children . METHODS We conducted a r and omized , placebo-controlled , multicenter trial in South Africa ( 3166 infants ; 64.1 % of the total ) and Malawi ( 1773 infants ; 35.9 % of the total ) to evaluate the efficacy of a live , oral rotavirus vaccine in preventing severe rotavirus gastroenteritis . Healthy infants were r and omly assigned in a 1:1:1 ratio to receive two doses of vaccine ( in addition to one dose of placebo ) or three doses of vaccine - the pooled vaccine group - or three doses of placebo at 6 , 10 , and 14 weeks of age . Episodes of gastroenteritis caused by wild-type rotavirus during the first year of life were assessed through active follow-up surveillance and were grade d with the use of the Vesikari scale . RESULTS A total of 4939 infants were enrolled and r and omly assigned to one of the three groups ; 1647 infants received two doses of the vaccine , 1651 infants received three doses of the vaccine , and 1641 received placebo . Of the 4417 infants included in the per- protocol efficacy analysis , severe rotavirus gastroenteritis occurred in 4.9 % of the infants in the placebo group and in 1.9 % of those in the pooled vaccine group ( vaccine efficacy , 61.2 % ; 95 % confidence interval , 44.0 to 73.2 ) . Vaccine efficacy was lower in Malawi than in South Africa ( 49.4 % vs. 76.9 % ) ; however , the number of episodes of severe rotavirus gastroenteritis that were prevented was greater in Malawi than in South Africa ( 6.7 vs. 4.2 cases prevented per 100 infants vaccinated per year ) . Efficacy against all-cause severe gastroenteritis was 30.2 % . At least one serious adverse event was reported in 9.7 % of the infants in the pooled vaccine group and in 11.5 % of the infants in the placebo group . CONCLUSIONS Human rotavirus vaccine significantly reduced the incidence of severe rotavirus gastroenteritis among African infants during the first year of life . ( Clinical Trials.gov number , NCT00241644 . ) Co-administration of oral live-attenuated human rotavirus vaccine RIX4414 ( Rotarix ) and oral polio vaccine ( OPV ) was assessed . Healthy infants were r and omised to receive 2-doses of either : RIX4414 or placebo co-administered with OPV ( 12 and 16 weeks of age ) ; or RIX4414 or placebo given 15 days after OPV . After vaccination , 56.5 - 66.7 % of RIX4414 and 18.6 % of placebo recipients had seroconverted for rotavirus IgA. No significant differences between RIX4414 groups with or without OPV co-administration were observed . No statistically significant differences were observed between groups for polio seroprotection rates . RIX4414 vaccine was immunogenic when co-administered with OPV and did not interfere with OPV seroprotection rates Background : Mexico initiated mass vaccination with the attenuated human rotavirus vaccine ( Rotarix ) in 2006 . This postlicensure study aim ed to assess any potential temporal association between vaccination and intussusception in Mexican infants . Methods : Prospect i ve , active surveillance for intussusception among infants aged less than 1 year was conducted in 221 hospitals across Mexico from the Mexican Institute of Social Security between January 2008 and October 2010 . The temporal association between vaccination and intussusception was assessed by self-controlled case-series analysis . Results : Of the 753 episodes of intussusception reported in 750 infants , 701 were in vaccinated infants ( 34.5 % post – dose 1 , 65.5 % post – dose 2 ) . The relative incidence of intussusception within 31 days of vaccination was 1.75 ( 95.5 % confidence interval [ CI ] : 1.24–2.48 ; P = 0.001 ) post – dose 1 and 1.06 ( 95.5 % CI : 0.75–1.48 ; P = 0.75 ) post – dose 2 . The relative incidence of intussusception within 7 days of vaccination was 6.49 post – dose 1 ( 95.5 % CI : 4.17–10.09 ; P < 0.001 ) and 1.29 post – dose 2 ( 95.5 % CI : 0.80–2.11 ; P = 0.29 ) . Clustering of intussusception within 7 days of vaccination was observed post – dose 1 . An attributable risk of 3 to 4 additional cases of intussusception per 100,000 vaccinated infants was estimated . Conclusion : This is the largest surveillance study for intussusception after rotavirus vaccination to date . A temporal increase in the risk for intussusception was seen within 7 days of administration of the first vaccine dose . It is still uncertain whether rotavirus vaccination has any impact on the overall incidence of intussusception . This finding has to be put in perspective with the well-documented substantial benefits of rotavirus vaccination BACKGROUND The safety and efficacy of an attenuated G1P[8 ] human rotavirus ( HRV ) vaccine were tested in a r and omized , double-blind , phase 3 trial . METHODS We studied 63,225 healthy infants from 11 Latin American countries and Finl and who received two oral doses of either the HRV vaccine ( 31,673 infants ) or placebo ( 31,552 infants ) at approximately two months and four months of age . Severe gastroenteritis episodes were identified by active surveillance . The severity of disease was grade d with the use of the 20-point Vesikari scale . Vaccine efficacy was evaluated in a subgroup of 20,169 infants ( 10,159 vaccinees and 10,010 placebo recipients ) . RESULTS The efficacy of the vaccine against severe rotavirus gastroenteritis and against rotavirus-associated hospitalization was 85 percent ( P<0.001 for the comparison with placebo ) and reached 100 percent against more severe rotavirus gastroenteritis . Hospitalization for diarrhea of any cause was reduced by 42 percent ( 95 percent confidence interval , 29 to 53 percent ; P<0.001 ) . During the 31-day window after each dose , six vaccine recipients and seven placebo recipients had definite intussusception ( difference in risk , -0.32 per  
    Output:
    
agent
***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: Rotavirus ( RV ) infection is the primary cause for childhood gastroenteritis worldwide . In Korea , RV infection is most common among children less than 5 y of age . This post-licensure study was conducted to further evaluate the RV vaccine ( RIX4414 ) to provide additional local clinical data to the Korean Food and Drug Association . Healthy infants aged 6–12 weeks were enrolled to receive two doses of either RIX4414 or placebo as per 0 , 1–2 mo schedule . Blood sample s were collected before dose-1 and one month post-dose-2 of RIX4414/placebo to assess serum anti-RV IgA antibody concentrations using ELISA . Gastroenteritis stool sample s were tested for the presence of RV using ELISA . RV positive sample s were subjected to further analysis for G and P typing . Among 684 infants enrolled and vaccinated , 432 infants ( RIX4414 = 318 ; placebo = 114 ) were included in the according-to- protocol cohort for immunogenicity . The anti-RV IgA antibody seroconversion rates in the RIX4414 group following one month post-dose-2 were 88.1 % ( 95 % CI : 84.0–91.4 ) and the corresponding geometric mean concentration in the RIX4414 group was 208.5 U/ml ( 95 % CI : 174.2–249.5 ) . Occurrence of solicited and unsolicited adverse events were similar in both , RIX4414 and placebo groups . None of the gastroenteritis stool sample s tested positive for RV and no fatal SAEs were reported in either groups . The two-dose regimen of RIX4414 was observed to be immunogenic with a similar safety profile as compared with the placebo group , when administered to healthy Korean infants Objective . Revaccination policies adopted in many countries to control measles have raised various safety issues including those concerning the second vaccine dose . We performed a prospect i ve , double-blind , crossover trial among twins receiving a measles-mumps-rubella ( MMR ) vaccine .  Study Design . The study comprised 1162 monozygous and heterozygous twins , each of whom r and omly received placebo and then vaccine , or vice versa , 3 weeks apart , at 14 to 83 months of age . Most of the oldest children had previously been vaccinated against measles , and one half of the remainder of children had had the disease . Symptoms and signs were recorded daily on structured forms . Statistical methods included a complex analysis of the vaccine attributability of the symptoms and conditional logistic regression . Results . Vaccination-attributable events occurred in 6 % overall . At 14 to 18 months of age , reactions developed between days 6 and 14 , peaking at day 10 . The clearest vaccine-attributable effect was fever exceeding 101.3 ° F ( 38.5 ° C ; odds ratio : 3.28 ; 95 % confidence interval : 2.23–4.82 ; P < .001 ) , but the same trend was found for rash , arthralgia , conjunctivitis , staying in bed , drowsiness , and irritability . At 6 years of age , systemic reactions occurred 5 to 15 times less frequently , only arthralgia being associated with vaccination . Zygocity , gender , history of allergy , or infections did not modify reactions . Instead , respiratory symptoms developed within days postinjection to a level of 15 % to 20 % without subsequent decline and with no difference between vaccinees and placebo recipients . Conclusion . Vaccination was avoided during infections , but many small children became mildly ill within a week or so with no relation to vaccination ( the healthy vaccinee effect ) . MMR vaccine was virtually nonreactogenic when given at 6 years of age . vaccine , measles , mumps , rubella , reactogenicity , adverse events , zygocity , healthy vaccinee effect The vast majority of adverse reactions following immunisation of children with live measles-mumps-rubella ( MMR ) vaccine  were shown in a double-blind , placebo-controlled , cross-over study in 581 twin pairs to be only temporally but not causally related to the vaccination . The true frequency of side-effects caused by MMR vaccine , estimated from the discordance rates of individual signs and symptoms between MMR vaccinees and their placebo-injected twins , was between 0.5 and 4.0 % . Moreover , respiratory symptoms , nausea , and vomiting were observed more frequently in the placebo-injected group than in the MMR vaccinated group Summary Previous studies have suggested that infant vaccinations may reduce the risk of subsequent childhood leukaemia .  Vaccination histories were compared in 439 children ( ages 0–14 ) diagnosed with acute lymphoblastic leukaemia ( ALL ) in nine Midwestern and Mid-Atlantic states ( USA ) between 1 January 1989 and 30 June 1993 and 439 controls selected by r and om-digit dialing and individually matched to cases on age , race and telephone exchange . Among matched pairs , similar proportions of cases and controls had received at least one dose of oral poliovirus ( 98 % ) , diphtheria – tetanus – pertussis ( 97 % ) , and measles – mumps – rubella ( 90 % ) vaccines . Only 47 % of cases and 53 % of controls had received any  Haemophilus influenzae type b ( Hib ) vaccine  ( relative risk ( RR ) = 0.73 ; 95 % confidence interval ( CI ) 0.50–1.06 ) . Although similar proportions of cases ( 12 % ) and controls ( 11 % ) received the polysaccharide Hib vaccine ( RR = 1.13 ; 95 % CI 0.64–1.98 ) , more controls ( 41 % ) than cases ( 35 % ) received the conjugate Hib vaccine ( RR = 0.57 ; 95 % CI 0.36–0.89 ) . Although we found no relationship between most infant vaccinations and subsequent risk of childhood ALL , our findings suggest that infants receiving the conjugate Hib vaccine may be at reduced risk of subsequent childhood acute lymphoblastic leukemia . Further studies are needed to confirm this association and , if confirmed , to eluci date the underlying mechanism BACKGROUND Rotavirus is the most common cause of severe gastroenteritis among young children worldwide . Data are needed to assess the efficacy of the rotavirus vaccine in African children . METHODS We conducted a r and omized , placebo-controlled , multicenter trial in South Africa ( 3166 infants ; 64.1 % of the total ) and Malawi ( 1773 infants ; 35.9 % of the total ) to evaluate the efficacy of a live , oral rotavirus vaccine in preventing severe rotavirus gastroenteritis . Healthy infants were r and omly assigned in a 1:1:1 ratio to receive two doses of vaccine ( in addition to one dose of placebo ) or three doses of vaccine - the pooled vaccine group - or three doses of placebo at 6 , 10 , and 14 weeks of age . Episodes of gastroenteritis caused by wild-type rotavirus during the first year of life were assessed through active follow-up surveillance and were grade d with the use of the Vesikari scale . RESULTS A total of 4939 infants were enrolled and r and omly assigned to one of the three groups ; 1647 infants received two doses of the vaccine , 1651 infants received three doses of the vaccine , and 1641 received placebo . Of the 4417 infants included in the per- protocol efficacy analysis , severe rotavirus gastroenteritis occurred in 4.9 % of the infants in the placebo group and in 1.9 % of those in the pooled vaccine group ( vaccine efficacy , 61.2 % ; 95 % confidence interval , 44.0 to 73.2 ) . Vaccine efficacy was lower in Malawi than in South Africa ( 49.4 % vs. 76.9 % ) ; however , the number of episodes of severe rotavirus gastroenteritis that were prevented was greater in Malawi than in South Africa ( 6.7 vs. 4.2 cases prevented per 100 infants vaccinated per year ) . Efficacy against all-cause severe gastroenteritis was 30.2 % . At least one serious adverse event was reported in 9.7 % of the infants in the pooled vaccine group and in 11.5 % of the infants in the placebo group . CONCLUSIONS Human rotavirus vaccine significantly reduced the incidence of severe rotavirus gastroenteritis among African infants during the first year of life . ( Clinical Trials.gov number , NCT00241644 . ) Co-administration of oral live-attenuated human rotavirus vaccine RIX4414 ( Rotarix ) and oral polio vaccine ( OPV ) was assessed . Healthy infants were r and omised to receive 2-doses of either : RIX4414 or placebo co-administered with OPV ( 12 and 16 weeks of age ) ; or RIX4414 or placebo given 15 days after OPV . After vaccination , 56.5 - 66.7 % of RIX4414 and 18.6 % of placebo recipients had seroconverted for rotavirus IgA. No significant differences between RIX4414 groups with or without OPV co-administration were observed . No statistically significant differences were observed between groups for polio seroprotection rates . RIX4414 vaccine was immunogenic when co-administered with OPV and did not interfere with OPV seroprotection rates Background : Mexico initiated mass vaccination with the attenuated human rotavirus vaccine ( Rotarix ) in 2006 . This postlicensure study aim ed to assess any potential temporal association between vaccination and intussusception in Mexican infants . Methods : Prospect i ve , active surveillance for intussusception among infants aged less than 1 year was conducted in 221 hospitals across Mexico from the Mexican Institute of Social Security between January 2008 and October 2010 . The temporal association between vaccination and intussusception was assessed by self-controlled case-series analysis . Results : Of the 753 episodes of intussusception reported in 750 infants , 701 were in vaccinated infants ( 34.5 % post – dose 1 , 65.5 % post – dose 2 ) . The relative incidence of intussusception within 31 days of vaccination was 1.75 ( 95.5 % confidence interval [ CI ] : 1.24–2.48 ; P = 0.001 ) post – dose 1 and 1.06 ( 95.5 % CI : 0.75–1.48 ; P = 0.75 ) post – dose 2 . The relative incidence of intussusception within 7 days of vaccination was 6.49 post – dose 1 ( 95.5 % CI : 4.17–10.09 ; P < 0.001 ) and 1.29 post – dose 2 ( 95.5 % CI : 0.80–2.11 ; P = 0.29 ) . Clustering of intussusception within 7 days of vaccination was observed post – dose 1 . An attributable risk of 3 to 4 additional cases of intussusception per 100,000 vaccinated infants was estimated . Conclusion : This is the largest surveillance study for intussusception after rotavirus vaccination to date . A temporal increase in the risk for intussusception was seen within 7 days of administration of the first vaccine dose . It is still uncertain whether rotavirus vaccination has any impact on the overall incidence of intussusception . This finding has to be put in perspective with the well-documented substantial benefits of rotavirus vaccination BACKGROUND The safety and efficacy of an attenuated G1P[8 ] human rotavirus ( HRV ) vaccine were tested in a r and omized , double-blind , phase 3 trial . METHODS We studied 63,225 healthy infants from 11 Latin American countries and Finl and who received two oral doses of either the HRV vaccine ( 31,673 infants ) or placebo ( 31,552 infants ) at approximately two months and four months of age . Severe gastroenteritis episodes were identified by active surveillance . The severity of disease was grade d with the use of the 20-point Vesikari scale . Vaccine efficacy was evaluated in a subgroup of 20,169 infants ( 10,159 vaccinees and 10,010 placebo recipients ) . RESULTS The efficacy of the vaccine against severe rotavirus gastroenteritis and against rotavirus-associated hospitalization was 85 percent ( P<0.001 for the comparison with placebo ) and reached 100 percent against more severe rotavirus gastroenteritis . Hospitalization for diarrhea of any cause was reduced by 42 percent ( 95 percent confidence interval , 29 to 53 percent ; P<0.001 ) . During the 31-day window after each dose , six vaccine recipients and seven placebo recipients had definite intussusception ( difference in risk , -0.32 per  
    Output:
    