***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: Background Atypical antipsychotics are widely used in the treatment of bipolar disorders .  Amisulpride is an atypical antipsychotic that has been proven to be effective in treatment of schizophrenia , major depressive disorder and , more recently , acute mania . At the moment , however , no study has assessed the effectiveness of this compound in maintenance therapy of bipolar disorders . The purpose of this study was to assess the long-term effectiveness of amisulpride in combination with st and ard treatments in patients with bipolar I disorder who have shown inadequate responses to ongoing st and ard therapies .  Methods The study enrolled fourteen bipolar I out patients , not responding to ongoing st and ard therapy .  Three patients discontinued treatment but 11 were followed-up for 11.7 ± 8.2 months before ( range 3–24 months ) and 5.2 ± 2.7 months after the introduction of amisulpride ( range 3–9 months ) . Relapse rates before and during treatment with amisulpride were calculated in accordance to an increase of 1 or more in Clinical Global Impressions Scale-Bipolar Version ( CGI-BP ) score that was accompanied by a change in therapy or to an exacerbation of the symptoms that required hospitalization . Results A statistically significant decrease in overall relapse rate was observed during the period of amisulpride therapy compared with months previous to the introduction of amisulpride . The relative risk of relapse in the absence of amisulpride therapy was 3.1 ( χ2 = 4.2 , P < 0.05 ) . Similarly , the rates of manic/mixed and depressive relapse were decreased but only manic episodes reached statistical significance ( RR = 5.3 , χ2 = 5.2 , P < 0.02 ) . Discussion and conclusion This open-label study suggests that long-term therapy with amisulpride may benefit patients by improving global symptoms of bipolar disorder and reducing the rate of manic/mixed relapses . Large , r and omized , double-blind , placebo-controlled studies are needed to explore the benefits of adding long-term amisulpride to st and ard therapies for bipolar disorder BACKGROUND During 1990 and 1991 a survey of immunity was carried out in Sweden . The main purpose was to estimate the level of immunity to diphtheria , tetanus and polio in the adult population . In total , 4800 people , r and omly selected according to a stratified , two-stage , sampling plan , were contacted and asked to contribute a blood sample . Of those selected , 70.6 % gave a blood sample . METHODS Estimates and confidence intervals of the proportion of the population with antibodies exceeding some titre was calculated . The population was divided according to sex , year of birth ( five age groups ) and residence ( four regions ) . RESULTS In age groups that were born after the introduction of childhood vaccination , > or = 90 % and 75 - 90 % of people have demonstrable antibodies at a protective level against tetanus and diphtheria respectively . Those born earlier , especially women , are poorly protected with less than 50 % having protective antibody levels for both tetanus and diphtheria . Differences between men and women were particularly seen in the age groups born between 1930 and 1950 . Less than 5 % of the Swedish population lacked the protective level antibodies against polio types 1 , 2 and 3 respectively . CONCLUSIONS Vaccination against tetanus , which can be combined with vaccination against diphtheria , can be recommended especially to women born before 1950 and with no documented previous vaccination . The same recommendation can be given for men born before the 1930s . As regards poliomyelitis , general booster vaccination of the adult population does not appear to be necessary at present Background Treatment of urinary schistosomiasis by chemotherapy remains challenging due to rapid re-infection and possibly to limited susceptibility to praziquantel treatment . Therefore , therapeutic vaccines represent an attractive alternative control strategy . The objectives of this study were to assess the safety and tolerability profile of the recombinant 28 kDa glutathione S-transferase of Schistosoma haematobium ( rSh28GST )  in healthy volunteers , and to determine its immunogenicity . Methodology Volunteers r and omly received 100 µg rSh28GST together with aluminium hydroxide ( Alum ) as adjuvant ( n = 8) , or Alum alone as a comparator ( n = 8) , twice with a 28-day interval between doses . A third dose of rSh28GST or Alum alone was administered to this group at day 150 . In view of the results obtained , another group of healthy volunteers ( n = 8) received two doses of 300 µg of rSh28GST , again with a 28-day interval . A six-month follow-up was performed with both clinical and biological evaluations . Immunogenicity of the vaccine c and i date was evaluated in terms of specific antibody production , the capacity of sera to inhibit enzymatic activity of the antigen , and in vitro cytokine production . Principal Findings Among the 24 healthy male participants no serious adverse events were reported in the days or weeks after administration . Four subjects under rSh28GST reported mild reactions at the injection site while a clinical ly insignificant increase in bilirubin was observed in 8/24 subjects . No hematological nor biochemical evidence of toxicity was detected . Immunological analysis showed that rSh28GST was immunogenic . The induced Th2-type response was characterized by antibodies capable of inhibiting the enzymatic activity of rSh28GST . Conclusions rSh28GST in Alum did not induce any significant toxicity in healthy adults and generated a Th2-type immune response . Together with previous pre clinical results , the data of safety , tolerability and quality of the specific immune response provide evidence that clinical trials with rSh28GST could be continued in humans as a potential vaccine c and i date against urinary schistosomiasis BACKGROUND The current recommended control strategy for schistosomiasis is annual treatment using 40 mg/kg of praziquantel . However , praziquantel is only effective on adult worms and giving a second dose may increase its efficacy . We assessed the effect of one versus two doses of praziquantel on cure rate and re-infection with Schistosoma mansoni in a high endemic community along Lake Victoria , Ug and a. METHODOLOGY To investigate the effect of the two regimens , 395 infected people were r and omised into two groups ; one received a single st and ard dose of praziquantel ( Distocide ® 600 mg , Shin Poong Pharmaceuticals , Seoul , Republic of Korea ) , 40mg/kg body weight , while the other group received a second dose 2 weeks later  . Cure rate and infection intensity were assessed 9 weeks after the first treatment using st and ard parasitological procedures . Re-infection levels were monitored 8 and 24 months after treatment . RESULTS Those who received two doses were more likely to be cured ( 69.7 % ) compared to those who received a single dose ( 47.9 % ) ( χ(2 ) = 18.5 , p < 0.001 ) . Geometric mean intensity ( GMI ) of infection at 9 weeks ( eggs per gram of faeces [ epg ] ) was 12.0 epg ( CI95 : 8.9 - 16.1 ) for individuals who received 2 doses and 22.1 epg ( CI95 : 16.9 - 28.8 ) for those in the single dose arm . Eight months after treatment , prevalence of re-infection for individuals in the double dose arm ( 61.6 % , CI95 : 50.2 - 73.1 ) was not significantly different from that of those in a single dose arm ( 68.3 % , CI95 : 59.9 - 76.8 ) . The difference in GMI of re-infection for individuals in the single dose arm ( 33.8 epg , CI95 : 23.2 - 49.3 ) and those in the double dose arm ( 34.5 epg , CI95 : 24.7 - 48.1 ) was not significant . Twenty four months after treatment , prevalence of re-infection was not significantly different . The difference in GMI of re-infection for those in the single dose arm ( 57.5 epg , CI95 : 33.9 - 97.5 ) and those in the double dose arm ( 42.2 epg , CI95 : 29.9 - 59.6 ) was also insignificant . CONCLUSION Our results suggest that a second dose of praziquantel given 2 weeks after the first dose improves cure rate and reduces S. mansoni infection intensity . However , there is no added advantage on reduction of S. mansoni re-infection by administering two doses of praziquantel . CLINICAL TRIALS.GOV IDENTIFIER : NCT00215267 Malaria Sporozoite Vaccine Each year , hundreds of millions of people are infected with Plasmodium falciparum , the mosquito-borne parasite that causes malaria . A preventative vaccine is greatly needed . Seder et al. ( p. 1359 , published online 8 August ; see the Perspective by Good ) now report the results from a phase I clinical trial where subjects were immunized intravenously with a whole , attenuated sporozoite vaccine .  Three of 9 subjects who received four doses and zero of 6 subjects who received five doses of the vaccine went on to develop malaria after controlled malaria infection . Both antibody titers and cellular immune responses correlated positively with the dose of vaccine received , suggesting that both arms of the adaptive immune response may have participated in the observed protection . Intravenous immunization with an attenuated whole malaria sporozoite vaccine protected volunteers in a phase I clinical trial . [ Also see Perspective by Good ] Consistent , high-level , vaccine-induced protection against human malaria has only been achieved by inoculation of Plasmodium falciparum ( Pf ) sporozoites ( SPZ ) by mosquito bites . We report that the PfSPZ Vaccine — composed of attenuated , aseptic , purified , cryopreserved PfSPZ — was safe and wel-tolerated when administered four to six times intravenously ( IV ) to 40 adults . Zero of six subjects receiving five doses and three of nine subjects receiving four doses of 1.35 × 105 PfSPZ Vaccine and five of six nonvaccinated controls developed malaria after controlled human malaria infection ( P = 0.015 in the five-dose group and P = 0.028 for overall , both versus controls ) . PfSPZ-specific antibody and T cell responses were dose-dependent . These data indicate that there is a dose-dependent immunological threshold for establishing high-level protection against malaria that can be achieved with IV administration of a vaccine that is safe and meets regulatory st and ards BACKGROUND We have shown that immunity to infection with Plasmodium falciparum can be induced experimentally in malaria-naive volunteers through immunisation by bites of infected mosquitoes while simultaneously preventing disease with chloroquine prophylaxis . This immunity was associated with parasite-specific production of interferon γ and interleukin 2 by pluripotent effector memory cells in vitro . We aim to explore the persistence of protection and immune responses in the same volunteers . METHODS In an open-label study at the Radboud University Nijmegen Medical Centre ( Nijmegen , Netherl and s ) , from November to December , 2009 , we rechallenged previously immune volunteers ( 28 months after immunisation ) with the bites of five mosquitoes infected with P falciparum .  Newly recruited malaria-naive volunteers served as infection controls . Our primary outcome was the detection of blood-stage parasitaemia by microscopy . We assessed the kinetics of parasitaemia with real-time quantitative PCR ( rtPCR ) and recorded clinical signs and symptoms . In-vitro production of interferon γ and interleukin 2 by effector memory T cells was studied after stimulation with sporozoites and red blood cells infected with P falciparum . Differences in cellular immune responses between the study groups were assessed with the Mann-Whitney test . This study is registered with Clinical Trials.gov , number NCT00757887 . FINDINGS Four of six immune volunteers  were microscopically negative after rechallenge . rtPCR-based detection of blood-stage parasites in these individuals was negative throughout follow-up . Patent parasitaemia was delayed in the remaining two immunised volunteers . In-vitro assays showed the long-term persistence of parasite-specific pluripotent effector memory T-cell responses in protected volunteers . The four protected volunteers reported several mild to moderate adverse events , of which the most commonly reported symptom was headache ( one to three episodes per volunteer ) . The two patients with delayed patency had adverse events similar to those in the control group . INTERPRETATION Artificially induced immunity lasts longer than generally recorded after natural exposure ; providing a new avenue of research into the mechanisms of malaria immunity . FUNDING Dioraphte Foundation The efficacy of a sporozoite-based malaria vaccine is tested in humans , nonhuman primates , and mice . Our goal is to develop a vaccine that sustainably prevents Plasmodium falciparum ( Pf ) malaria in 
    Output:
    
Models showed that the irradiated cercariae vaccine has the potential to achieve protection as high as 78 % with a single dose vaccination .
This declines slowly over time but remains high for at least 8 months after the last immunization .