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At least 253 records · Page 14Linked to original sources
PubMed2005

Safety of varying dosages of 7-valent pneumococcal protein conjugate vaccine in seniors previously vaccinated with 23-valent pneumococcal polysaccharide vaccine.

In a phase I/II dose escalation study, varying volumes (0.1 ml, 0.5 ml, 1.0 ml and 2.0 ml) of 7-valent pneumococcal conjugate vaccine (PCV) (Prevnar or 0.5 ml of 23-valent pneumococcal polysaccharide vaccine (PPV) were administered to 220 adults 70 through 79 years of age previously vaccinated with 0.5 ml PPV at age 65 years or above and at least 5 years previously. Fever was uncommon and did not vary by study group. The rate of local reactions increased with higher volumes of PCV and the rate following 2.0 ml of PCV was comparable to that following 0.5 ml PPV.

Aged↗
PubMed1995

Persistence of anti-HBs antibodies in health care personnel vaccinated with plasma-derived hepatitis B vaccine and response to recombinant DNA HB booster vaccine.

Long-term persistence of specific antibodies after primary immunization against HBV infection has been reported. In this study, we evaluated the persistence of anti-HBs in vaccinees 6 years after primary immunization and the response to a booster dose using a recombinant DNA yeast-derived HB vaccine. An 85.4% seroprotection rate was observed after 6 years with a significantly higher seroprotective rate in those subjects who received four doses of vaccine primary immunization as compared with those who received three doses (93.9% versus 67.2%, p < 0.001). One month after receiving the booster dose, 98.6% of the subjects had an anamnestic type of response. The GMTs were found to decrease progressively with increasing age. The antibody levels after booster dose were higher than those attained at the end of primary immunization and reflected the trend seen before the administration of the booster. These results are consistent with the existence of an effective immunological memory in HB vaccine responders. Subjects who received four doses during primary immunization were better seroprotected and had a higher seroprotection rate after the booster dose.

Adolescent↗
PubMed1994

Congenital rubella syndrome despite repeated vaccination of the mother: a coincidence of vaccine failure with failure to vaccinate.

Congenital rubella syndrome occurred in a boy born to a mother who had been properly vaccinated three times before conception, but developed only low titers of rubella antibody. The non-vaccinated father most likely infected the mother on a home visit during the third to fifth weeks of gestation. He served in the army and fell ill during an outbreak of a rubella-like disease in his military unit. The mother subsequently developed a slight rash, but rubella IgM antibodies were lacking and rubella infection was not suspected. This incidence demonstrates the necessity of vaccinating all children, including boys and young men, in order to reduce the number of infections and prevent further cases of congenital rubella syndrome.

Adult↗
PubMed1978

Immunity to Brucella in mice vaccinated with a fraction (F8) or a killed vaccine (H38) with or without adjuvant. Level and duration of immunity in relation to dose of vaccine, recall injection and age of mice.

Immunity to Brucella in the mouse, assessed by bacterial spleen counts 15 days after intraperitoneal inoculation of a standard challenge of B. abortus 544, has been studied with two vaccines, one experimental, composed of a fraction of the bacterial cell-wall (F8) extracted from B. abortus 99, the other of killed whole bacteria, B. melitensis 53 H38, taken as reference (H38). The level of primary immunity depended on the dose of vaccine, the presence of oil adjuvant and the age of the mouse. The presence of adjuvant enabled the immunization to F8 to continue beyond the first month, to reach its maximum around the fourth month, and to remain stable for at least 7 months. A booster injection 3 or 6 months after the primary vaccination reinforced existing immunity but did not increase it beyond a certain level. The effect of the recall injection was clearly demonstrated with low doses which gave a lower level of primary immunity.

Adjuvants, Immunologic↗
PubMed1997

Humoral and mucosal immunity in infants induced by three sequential inactivated poliovirus vaccine-live attenuated oral poliovirus vaccine immunization schedules. Baltimore Area Polio Vaccine Study Group.

The relative immunity induced by sequential administration of inactivated poliovirus vaccine (IPV) produced in human diploid cells and live attenuated oral poliovirus vaccine (OPV) was evaluated by randomization of 510 infants to receive IPV and OPV sequentially according to one of three experimental schedules, IPV only, or OPV only. The antibody response to two IPV doses was lower than expected. However, for each of the IPV-OPV sequential schedules, the first OPV dose significantly enhanced seroconversion rates and geometric mean microneutralization antibody titers. Three months after the final dose, 96%-99%, 99%-100%, and 81%-100% of infants had antibodies to poliovirus types 1, 2, and 3, respectively, and subjects with two or more prior OPV doses were significantly less likely than those with none or one prior OPV dose to excrete virus in feces after an OPV challenge. Sequential IPV-OPV immunization is now recommended for routine use in the United States. The optimal schedule consists of two IPV doses followed by two OPV doses.

Antibodies, Viral↗
PubMed1997

Twenty years' experience of rubella vaccination in Sweden: 10 years of selective vaccination (of 12-year-old girls and of women postpartum) and 13 years of a general two-dose vaccination.

Two different strategies for the prevention of rubella-induced malformations have now been practised in Sweden, both reaching 90% or more of the target populations. The first was initiated in 1973-1974 and targeted schoolgirls, susceptible women after pregnancy and women at special risk. The second programme-a two-dose measles, mumps, rubella vaccination (MMR) of both boys and girls at the ages of 18 months and 12 years-was introduced in 1982. The percentage of susceptible pregnant women was gradually reduced from 12% in 1975 to 2.8% in 1987 and to just below 2% in 1994. The majority of the non immune are unvaccinated, these being either Swedes born before 1963 or immigrants. Before 1974 on average 14 severely rubella damaged children were reported yearly. Between 1975 and 1985 only a mean of two cases per year were recorded. Since 1985 no child with the rubella syndrome has been registered.

Adolescent↗
PubMed2004

Do changes in policy affect vaccine coverage levels? Results of a national study to evaluate childhood vaccination coverage and reasons for missed vaccination in Italy.

To evaluate the impact of actions taken in Italy since 1998 to improve vaccination coverage, a national EPI-survey was performed in 2003. Overall, 4602 children aged 12-24 months participated in the study; coverage was calculated for three doses of DT, polio, HBV, pertussis, and Hib, and for one dose of MMR/measles vaccine for children > or =16 months of age. Since 1998, when the last national survey was conducted, DT, polio, and HBV coverage have remained consistently high (95%), while pertussis, Hib, and MMR/measles significantly increased. Pertussis coverage reached the 95% target, and Hib is close to target (87%). Improving MMR coverage (77%), however, remains a national priority.

Child↗
PubMed1997

Increased immunogenicity of oral poliovirus vaccine administered in mass vaccination campaigns compared with the routine vaccination program in Jordan.

To compare the immunogenicity of routine versus mass campaign doses of oral poliovirus vaccine (OPV), serum neutralizing antibodies were measured in 254 children before and after two mass vaccination campaigns in Jordan. Precampaign seroprevalences to poliovirus types 1, 2, and 3 in children who had received three, four, or five routine doses of OPV were compared with postcampaign seroprevalences in children who had received one, two, or three routine doses plus two mass campaign doses. Seroprevalences were consistently higher in subgroups that received two doses through mass campaigns than in subgroups that received all doses through the routine program, especially for poliovirus type 3. Geometric mean titers were also consistently higher for mass campaign subgroups, particularly for poliovirus type 3. The findings suggest that adding further doses of OPV to the routine schedule is unlikely to have as great an impact on the immune state of children as administering the same number of doses during mass campaigns.

Child, Preschool↗
PubMed1984

Oronasal and intramuscular vaccination of swine with a modified live porcine parvovirus vaccine: multiplication and transmission of the vaccine virus.

An attenuated strain NADL-2 of porcine parvovirus (PPV) has been used at the 54th cell culture passage as a modified live-virus (MLV) vaccine. The present study was conducted to determine the minimum immunizing dose of MLV, the extent of MLV multiplication in swine tissues, and its transmission from swine administered MLV oronasally or intramuscularly. Immune response to MLV was dose dependent and swine responded to as little as 10(2) median cell-culture infective doses (CCID50). A 10(5) CCID50 of MLV, the largest dose given, induced the best immune response and was used in subsequent experiments. Route of MLV administration also was found to be important. The MLV replicated in tissues of swine after IM inoculation; however, viral antigen in tissues was less, as measured by immunofluorescence, and serum hemagglutination-inhibition titers for PPV were lower in MLV-inoculated swine than we have previously observed in virulent PPV-inoculated swine. In contrast, oronasal inoculation with MLV did not consistently result in infection of pigs; only 5 of 23 swine had virologic and/or serologic evidence of infection. Virus transmission studies indicated that MLV is shed in feces, but shedding occurs later than that in virulent-PPV-inoculated swine and is inconsistent. Delayed transmission of MLV was observed in contact pigs, which were seronegative at 2 weeks, but became seropositive at 4 weeks--indicating that perhaps a virus population capable of infecting pigs by oronasal route was selected by passage through the pig.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed2003

Recommendations for using smallpox vaccine in a pre-event vaccination program. Supplemental recommendations of the Advisory Committee on Immunization Practices (ACIP) and the Healthcare Infection Control Practices Advisory Committee (HICPAC).

This report supplements the 2001 statement by the Advisory Committee on Immunization Practices (ACIP) (CDC. Vaccinia [smallpox] vaccine: recommendations of the Advisory Committee on Immunization Practices [ACIP], 2001. MMWR 2001;50[No. RR-10]:1-25). This supplemental report provides recommendations for using smallpox vaccine in the pre-event vaccination program in the United States. To facilitate preparedness and response, smallpox vaccination is recommended for persons designated by public health authorities to conduct investigation and follow-up of initial smallpox cases that might necessitate direct patient contact. ACIP recommends that each state and territory establish and maintain > or = 1 smallpox response team. ACIP and the Healthcare Infection Control Practices Advisory Committee (HICPAC) recommend that each acute-care hospital identify health-care workers who can be vaccinated and trained to provide direct medical care for the first smallpox patients requiring hospital admission and to evaluate and manage patients who are suspected as having smallpox. When feasible, the first-stage vaccination program should include previously vaccinated health-care personnel to decrease the potential for adverse events. Additionally persons administering smallpox vaccine in this pre-event vaccination program should be vaccinated. Smallpox vaccine is administered by using the multiple-puncture technique with a bifurcated needle, packaged with the vaccine and diluent. According to the product labeling, 2-3 punctures are recommended for primary vaccination and 15 punctures for revaccination. A trace of blood should appear at the vaccination site after 15-20 seconds; if no trace of blood is visible, an additional 3 insertions should be made by using the same bifurcated needle without reinserting the needle into the vaccine vial. If no evidence of vaccine take is apparent after 7 days, the person can be vaccinated again. Optimal infection-control practices and appropriate site care should prevent transmission of vaccinia virus from vaccinated health-care workers to patients. Health-care personnel providing direct patient care should keep their vaccination sites covered with gauze in combination with a semipermeable membrane dressing to absorb exudates and to provide a barrier for containment of vaccinia virus to minimize the risk of transmission; the dressing should also be covered by a layer of clothing. Dressings used to cover the site should be changed frequently to prevent accumulation of exudates and consequent maceration. The most critical measure in preventing contact transmission is consistent hand hygiene. Hospitals should designate staff to assess dressings for all vaccinated health-care workers. When feasible, staff responsible for dressing changes for smallpox health-care teams should be vaccinated, all persons handling dressings should observe contact precautions. Administrative leave is not required routinely for newly vaccinated health-care personnel unless they are physically unable to work as a result of systemic signs and symptoms of illness; have extensive skin lesions that cannot be adequately covered or if they are unable to adhere to the recommended infection-control precautions. Persons outside the patient-care setting can keep their vaccination sites covered with a porous dressing hand hygiene remains key to preventing inadvertent inoculation. FDA has recommended that recipients of smallpox vaccine be deferred from donating blood for 21 days or until the scab has separated. Contacts of vaccinees, who have inadvertently contracted vaccinia, also should be deferred from donating blood for 14 days after complete resolution of their complication. In the pre-event vaccination program, smallpox vaccination is contraindicated for persons with a history or presence of eczema or atopic dermatitis; who have other acute, chronic, or exfoliative skin conditions; who have conditions associated with immunosuppression; are aged < 1 year; who have a serious allergy to any component of the vaccine; or who are pregnant or breastfeeding. ACIP does not recommend smallpox vaccination for children and adolescents aged < 18 years during the pre-event vaccination program. Pre-event vaccination also is contraindicated among persons with household contacts who have a history or presence of eczema or atopic dermatitis; who have other acute, chronic, or exfoliative skin conditions; who have conditions associated with immunosuppression; or who are pregnant. For purposes of screening for contraindications for pre-event vaccination, household contacts include persons with prolonged intimate contact (e.g., sexual contacts) with the potential vaccinee and others who might have direct contact with the vaccination site. Persons with inflammatory eye disease might be at increased risk for inadvertent inoculation as a result of touching or rubbing the eye. Therefore, deferring vaccination is prudent for persons with inflammatory eye diseases requiring steroid treatment until the condition resolves and the course of therapy is complete. Eczema vaccinatum, a serious form of disseminated vaccinia infection, can occur among persons with atopic dermatitis and other dermatologic conditions. Potential vaccinees should be queried regarding the diagnosis of atopic dermatitis or eczema in themselves or any member of their household, or regarding the presence of chronic or recurrent rashes consistent with these diagnoses. Persons reporting such a rash in themselves or household members should not be vaccinated, unless a health-care provider determines that the rash is not eczema or atopic dermatitis. Before vaccination, women of childbearing age should be asked if they are pregnant or intend to become pregnant during the next 4 weeks; women who respond positively should not be vaccinated. Any woman who thinks she might be pregnant or who wants additional assurance that she is not pregnant should perform a urine pregnancy test on the day scheduled for vaccination. If a pregnant woman is inadvertently vaccinated or if she becomes pregnant within 4 weeks after smallpox vaccination, she should be counseled regarding concerns for the fetus. Vaccination during pregnancy should not ordinarily be a reason to terminate pregnancy. CDC has established a pregnancy registry to prospectively follow the outcome of such pregnancies and facilitate the investigation of any adverse pregnancy outcome among pregnant women who were inadvertently vaccinated. For enrollment in the registry, contact CDC at 404-639-8253. Smallpox vaccine should not be administered to persons with human immunodeficiency virus infection (HIV) or acquired immunodeficiency syndrome (AIDS) as part of a pre-event program because of their increased risk for progressive vaccinia. HIV testing is recommended for persons who have any history of a risk factor for HIV infection or for anyone who is concerned that he or she might have HIV infection. HIV testing should be available in a confidential or anonymous setting, in accordance with local laws and regulations, with results communicated to the potential vaccinee before the planned date of vaccination. Smallpox vaccine can be administered simultaneously with any inactivated vaccine. With the exception of varicella vaccine, smallpox vaccine can be administered simultaneously with other live-virus vaccines. To avoid confusion in ascertaining which vaccine might have caused postvaccination skin lesions or other adverse events, varicella vaccine and smallpox vaccine should be administered >4 weeks apart. Health-care workers scheduled to receive an annual purified protein derivative (PPD) skin test for tuberculosis screening should not receive the skin test until >1 month after smallpox vaccination. Persons with progressive vaccinia, eczema vaccinatum, and severe generalized vaccinia or inadvertent inoculation might benefit from therapy with VIG or cidofovir, although the latter has not been approved by FDA for this indication. Suspected cases of these illnesses or other severe adverse events after smallpox vaccination should be reported immediately to state health departments. VIG and cidofovir are available from CDC under Investigational New Drug protocols. Clinically severe adverse events after smallpox vaccination should be reported to the Vaccine Adverse Event Reporting System. Reports can be made online at https://secure.vaers.org/VaersDataEntryintro.htm, or by postage-paid form, which is available by calling 800-822-7967 (toll-free). ACIP will review these recommendations periodically as new information becomes available related to smallpox disease, smallpox vaccines, the risk of smallpox attack, smallpox vaccine adverse events, and the experience gained as recent recommendations are implemented. Revised recommendations will be developed as needed.

Bioterrorism↗
PubMed1980

A study of live influenza virus vaccine in patients with chronic bronchitis. Report to Medical Research Council's Committee on Influenza and Other Respiratory Virus Vaccines. Advisory Group on pulmonary function tests in relation to live influenza virus vaccines.

A multicentre study of the effects of influenza virus RIT 4050 (H3N2) in patients with chronic bronchitis was conducted by members of an MRC Committee. The results showed that RIT 4050 vaccine virus did not cause a deterioration in clinical or physiological status in these patients within the limitation of the relatively reproducible ventilatory tests which were employed. This conclusion applied equally to those who were inoculated and became infected and to those who failed to develop serological evidence of infection. The relatively high proportion of antibody-negative volunteers not infected by the inoculated virus raises doubts concerning the value of this method of immunization for patients at risk during influenza epidemics.

Adult↗
PubMed1994

[Clinical course of tuberculosis in young children, vaccinated and non-vaccinated with BCG vaccine].

As shown by the analysis of tuberculosis forms in 27 infants under 1 year of age (group 1) and 150 infants of older age (group 2), the involvement of the intrathoracic lymph nodes holds the first place among tuberculosis forms encountered in infants. Severe infection (tuberculous meningitis, disseminated tuberculosis) occurred more frequently in group 1. The authors emphasize epidemiological significance of contacts with tuberculous patients. To decrease infant tuberculosis incidence rate, it is of much more importance to make early diagnosis in the adults, to give infants preventive treatment, chemoprophylaxis in particular, than to perform BCG vaccination under conditions of close contacts with tuberculous subjects.

Adult↗
PubMed2000

Vaccines for preventing influenza in healthy adults.

OBJECTIVES: To identify, retrieve and assess all studies evaluating the effects of vaccines on influenza in healthy adults. To assess the effectiveness of vaccines in preventing cases of influenza in healthy adults. To estimate the frequency of adverse effects associated with influenza vaccination in healthy adults. SEARCH STRATEGY: MEDLINE was searched using the strategy of the Cochrane Acute Respiratory Infections Group. The bibliography of retrieved articles, the Cochrane Controlled Trials Register (CCTR), and EMBASE (1990 to 1997) were also searched. Handsearch of the journal Vaccine from its first issue to the end of 1997 (Jefferson and Jefferson, 1996; Jefferson, 1998). We wrote to vaccine manufacturers and first or corresponding authors of studies in the review. SELECTION CRITERIA: Any randomised or quasi-randomised studies comparing influenza vaccines in humans with placebo, control vaccines or no intervention, or comparing types, doses or schedules of influenza vaccine. Live, attenuated or killed vaccines or fractions thereof administered by any route, irrespective of antigenic configuration were considered. Only studies assessing protection from exposure to naturally occurring influenza in healthy individuals aged 14 to 60 (irrespective of influenza immune status) were considered. DATA COLLECTION AND ANALYSIS: Both clinically defined cases and serologically confirmed cases of influenza were considered as outcomes according to the authors' definitions. Time off work, complication and hospitalisation rates were considered, together with adverse effects. Vaccine schedules were analysed including one component matching the recommended vaccine (WHO or government recommendations) for the year of the study, and whether they matched the circulating viral subtypes. MAIN RESULTS: The recommended live aerosol vaccines reduced the number of cases of serologically confirmed influenza A by 48% (95% confidence interval 24% to 64%), whilst recommended inactivated parenteral vaccines had a vaccine efficacy of 68% (95% confidence interval 49% to 79%). The vaccines were less effective in reducing clinical influenza cases, with efficacies of 13% and 24% respectively. Use of the vaccine significantly reduced time off work, but only by 0.4 days for each influenza episode (95% confidence interval 0.1 to 0.8 days). Analysis of vaccines matching the circulating strain gave higher estimates of efficacy, whilst inclusion of all other vaccines reduced the efficacy. REVIEWER'S CONCLUSIONS: Influenza vaccines are effective in reducing serologically confirmed cases of influenza A. However, they are not as effective in reducing cases of clinical influenza. The use of WHO recommended vaccines appears to enhance their effectiveness in practice.

Adult↗
PubMed2001

Comparison of a triple antigen and a single antigen recombinant vaccine for adult hepatitis B vaccination.

Hepatitis B and its sequelae are a major public health problem. Vaccines have been available for almost 20 years; however the disease still remains a global problem. Many factors contribute to the failure to control hepatitis B, including the limited nature of the vaccination programs implemented initially. Only relatively recently has mass childhood vaccination begun to be implemented and vaccination of high-risk groups, other than healthcare workers, is still not general policy. Additional factors contributing to continued persistence of hepatitis B in the developed world are that the present vaccines are not fully used by those recommended to be vaccinated and even when vaccination is carried out appropriately, there remain some who fail to achieve adequate protection. Clearly, the protection of at-risk groups who have inadequate response to current vaccines, and those who are unwilling or unable to comply with protracted multi-dose vaccine regimens, could be improved if there were a more potent vaccine and/or a shorter vaccination regimen available. Adults who had never been vaccinated against hepatitis B were randomised to receive a vaccination course of either a present single antigen (S) vaccine (Recombivax-HB) or a novel triple antigen (S, pre-S1, and pre-S2) recombinant vaccine (Hepacare Medeva Pharma plc). Doses were given at baseline and 1 month and 6 months later. Hepatitis B surface antibody (anti-HBs) levels were measured at 2, 4, 6, and 7 months after beginning vaccination. The primary efficacy parameter was the degree of protection, measured as the percentage of subjects with anti-HBs titres > or = 10 IU/L, 6 or 7 months (26 +/- 2 weeks) after beginning vaccination. A total of 303 adult subjects entered the study and were vaccinated. Of these, 11 failed to complete the study (4 on Hepacare and 7 on Recombivax-HB); however all but 2 (1 to receive the triple antigen vaccine and 1 to receive Recombivax-HB) were included in the intent-to-treat population for efficacy evaluation. Treatment randomisation was stratified at entry based on age (above and below 40 years old) and gender. The standard three-dose/6-month vaccination regimen of the single antigen vaccine protected 83% of subjects by 7 months after starting vaccination whereas the triple antigen vaccine as a two-dose/1-month regimen protected 88% within 6 months and as a three-dose/6-month regimen protected 97% by 7 months after starting vaccination. Thus the protection rate provided by the shortened (0, 1) regimen of the novel vaccine was "essentially equivalent" (i.e., not statistically inferior) to that provided by the full (0, 1, and 6) regimen of today's vaccine (88% vs. 81%, P < 0.001), and the protection rate provided by a three-dose/6-month (0, 1, and 6) regimen of the new vaccine was significantly superior to that provided by present vaccines (97% vs. 83% P < 0.001). The percentage of subjects protected increases with time after beginning vaccination and at all time points up to and including 6 months was significantly greater with the two-dose regimen of the triple antigen vaccine than with the single antigen vaccine regimen. In adults at risk for a reduced response to hepatitis B vaccination [i.e., older adults (>/=40), the obese, males, and smokers], the triple antigen vaccine produced a significantly greater percentage of protected subjects (P < 0.001) and higher geometric mean titre (P < 0.001). Indeed as a three-dose/6 month regimen, the triple antigen vaccine raised the level of protection in these vulnerable subgroups to that seen when a single antigen vaccine is used in the optimal younger adult group. Both vaccines were well tolerated and had similar safety profiles. The most frequently (> or = 10%) reported adverse events with the use of either vaccine were pain at the site of injection (38% vs. 41% vs. 20% for the two-dose Hepacare regimen, the three-dose Hepacare regimen, and the three-dose Recombivax-HB regimen, respectively), infections at the site of injection (1% vs. 14% vs. 9%), headache (9% vs. 13% vs. 11%), and nausea (7% vs. 11% vs. 3%). It is concluded that in healthy normal adults, a triple antigen hepatitis B vaccine that contained S and pre-S antigens produced an enhanced immunological response. This was exemplified by the novel vaccine's ability to overcome factors such as advancing age (> or = 40 years), obesity, and smoking, each of which is known to reduce the potential for protection with present recombinant S only vaccines. A two-dose/1-month (0 and 1) regimen of this triple antigen vaccine was as effective as the standard three-dose/6 month (0, 1, and 6) regimen of present single antigen vaccines. (c) 2001 Wiley-Liss, Inc.

Adolescent↗
PubMed2000

Vaccines for preventing malaria.

BACKGROUND: Despite continued efforts to control the disease, malaria remains a major health problem in many regions of the world, especially sub-Saharan Africa, and new ways to control or eradicate the disease are urgently needed. Two types of vaccine, SPf66 vaccine against the asexual stages, and NANP vaccines against the sporozoite stages of the Plasmodium parasite, have been tested in randomised clinical trials in endemic areas. OBJECTIVES: To assess the effects of malaria vaccines. SEARCH STRATEGY: The Cochrane Infectious Diseases Group trials register, the Cochrane Controlled Trials Register, Medline, Embase and reference lists of articles were searched. Organisations and researchers in the field were contacted. SELECTION CRITERIA: Randomised trials comparing vaccines against Plasmodium falciparum, P. vivax, P. malariae or P. ovale, and placebo. DATA COLLECTION AND ANALYSIS: Two independent reviewers assessed trial quality and conducted data extraction. MAIN RESULTS: Thirteen efficacy trials involving about 7700 people were included. There were nine trials of the Spf66 vaccine and four trials of the NANP vaccines. There was large heterogeneity between trials when investigating the effect of SPf66 in reducing incidence of the first attack of P. falciparum malaria. When trials were subcategorised by location, there was no evidence for effect of SPf66 in reducing incidence of P. falciparum in four African trials conducted in children under 5 years of age (Peto odds ratio [OR] = 0.96, 95% confidence interval [CI] 0.81 to 1.14). In five trials outside Africa with participants aged 2 years to adult, there was a reduction in incidence by SPf66 vaccine (Peto OR = 0.77, 95% CI 0.67 to 0.88, fixed effects model). Significant heterogeneity remained between trials conducted outside Africa. Using a random effects model for these five trials, the OR was 0.74 (95% CI 0.54 to 1.01). In five trials, there was no evidence for effect of the SPf66 vaccine on the incidence of the first attack of P. vivax malaria (OR 1.01, 95% CI 0.87 to 1.17). Trials to date have not indicated any severe adverse effects of SPf66 vaccine. In three trials of NANP-based vaccines, there was no evidence for protection by these vaccines against P. falciparum malaria (OR 1.12, 95% CI 0.64 to 1.93). REVIEWER'S CONCLUSIONS: There is no evidence for protection by SPf66 vaccines against P. falciparum in Africa. There is a modest reduction in attacks of P. falciparum malaria following vaccination with SPf66 in other regions. Further research with SPf66 vaccines in South America may be justified. Trials to date have not been of sufficient size to evaluate the effect of malaria vaccines on mortality or on severe malaria requiring admission to hospital. There was not enough evidence to evaluate the use of NANP vaccines.

Adult↗