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This report characterizes differences among early and late volunteers, and non-volunteers for personal characteristics and situational determinants of volunteering in an experimental dental peer review study. Differences were found for volunteers/non-volunteers for some items representing subject interest, expectation of a favorable evaluation, sociability, and achievement motivation.
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Travelers' diarrhea was studied prospectively in a group of 39 American Peace Corps Volunteers (PCVs) during their first five weeks in Kenya. Twenty-seven developed diarrheal disease and 12 remained well. Multiple episodes were documented in 11 of the symptomatic volunteers. Enterotoxigenic Escherichia coli of many serotypes producing heat-labile and/or heat-stable enterotoxin were isolated from 17 of the 27 volunteers with diarrhea and from 1 of the 12 well volunteers. The enterotoxigenic E. coli were more likely to be antibiotic sensitive than the non-enterotoxigenic E. coli. A serum antibody rise to the heat-labile toxin (LT) was detected in six symptomatic volunteers, five of whom had a positive culture for LT-producing E. coli, and from one asymptomatic, culture negative volunteer. Salmonella cubana was isolated from two volunteers, and three volunteers had serologic evidence of infection with human reovirus-like (rotavirus) agent. This study confirms the role of enterotoxigenic E. coli as a major cause of travelers' diarrhea and suggests that the disease is similar in widely separated geographic areas.
OBJECTIVE: This study aims to systematically synthesize qualitative evidence on facilitators and barriers to volunteer involvement in palliative care services, providing insights to inform strategies for strengthening volunteer support systems. METHODS: PubMed, Web of Science, Embase, Cochrane Library, Medline, EBSCO, ProQuest, China National Knowledge Infrastructure, Wanfang, VIP, and Sinomed were searched from inception to December 2025 to identify qualitative studies examining factors influencing volunteer participation in palliative care. Methodological quality was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Qualitative Research. Data were analyzed using Thomas and Harden's thematic synthesis approach and managed using NVivo 12.0 software, following the Enhancing Transparency in Reporting the Synthesis of Qualitative Research (ENTREQ) guidelines. RESULTS: Thirty-one studies involving 1042 participants were included, yielding 68 findings. Facilitators included intrinsic motivation and meaning-making at the individual level; supportive relationships and teamwork at the interpersonal level; structured support and professional recognition at the organizational level; social recognition and resource integration at the community level; and institutional safeguards and governmental incentives at the policy level. Barriers included emotional burden and limited competencies at the individual level; relationship conflicts and insufficient collaboration at the interpersonal level; management deficiencies at the organizational level; community resource imbalances at the community level; and inadequate regulations and incentives at the policy level. CONCLUSION: Volunteer participation in palliative care is influenced by multiple interacting factors. Strengthening training and support systems, enhancing team collaboration, and improving institutional frameworks may help sustain volunteer engagement and improve the quality of palliative care services.
A community-based volunteer program was organized to improve the quality of life for elderly individuals in the community. Each elderly client referred for the program from welfare and home health agencies, or from family and friends, was matched with a volunteer who visited regularly. The volunteers also assisted with transportation, sitting, home maintenance, and meal preparation when these services were not available. The goals of the program were to improve the quality of life of elderly in the community, to assist the clients to remain in their home setting despite physical limitations, to encourage positive attitudes toward the elderly by the volunteers, and to increase the community's awareness of the older person's needs. The program also included educational seminars on gerontology for volunteers and community members.
1. Symptomatic volunteers were recruited at two collaborating institutions for anti-anxiety and antidepressant drug trials. Advertisements were placed for volunteers with significant symptoms of anxiety, depression, or both, and who were not currently in treatment. 2. It was possible to recruit adequate numbers of volunteers who met the numerous criteria for severity of distress; and who were not ruled out by various exclusion criteria, such as medical contraindications, etc. 3. Acceptable homogeneity across the samples at the collaborating institutions was found for demographic characteristics, level of distress, duration of symptoms, etc. 4. Attrition rates for these volunteers were lower than for the typical anxiolytic and antidepressant trials using outpatients. 5. Symptomatic volunteers appear to present a feasible alternative to the increasingly diminishing pool of outpatients.
Intranasal vaccination with a single 0.5 ml dose of 10(7.0) EID 50 WRL 105 strain live influenza vaccine elicited four-fold or greater increases in circulating homotypic haemagglutinating inhibiting (HAI) antibody in 60 (64.5%) of 93 volunteers, or in 58 (74.4%) of 78 volunteers with HAI antibody titres before vaccination of less than or equal to 1/20. In comparison, in a group of volunteers vaccinated 9 months previously re-vaccination elicited antibody responses in only 4 (6.9%) of 58 volunteers, or in 3 (14.3%) of 21 volunteers with antibody titres before vaccination of less than or equal to 1/20. Titres of vaccine-induced antibody and antibody resulting from earlier natural infection appeared to fall slowly and at equivalent rates over a 9 month period.
Safeguards for healthy volunteers in drug studies have not been as strict as those involving patients. The shortcomings include the lack of surveillance over the scientific validity of the protocol and its ethical review, and over the financial inducements to volunteers. Recruitment is open to abuse because the volunteers may have some allegiance to the investigators. There is an urgent need to institute checks on these aspects. Most important, however, is the lack of legal safeguards for volunteers taking part in research done outside the pharmaceutical industry. The suggested procedure for obtaining consent, for health checks, and for providing compensation can be equitable to all concerned, and yet not restrict initiative, nor curtail research aims.
Normal subjects were admitted to a psychiatric unit devoted to the study and treatment of affective illness. Initially the authors were concerned about the difficulties volunteers might have living with psychiatric patients. However, the volunteers adjusted with relative ease, while the patients' depressive symptoms were exacerbated. Their confrontation with the volunteers "normality" triggered an acute awareness of their underlying sense of failure. This response is analogous to depressed patients' reactions before discharge, when they struggle not only with their special vulnerability to separation and loss but with inevitable challenges to their fragile self-esteem during reintegration into the outside world. The presence of normal volunteers highlighted these issues and led to increased therapeutic work and considerable resolution.
Two groups of volunteers who had participated in pharmacologic studies were interviewed about their impressions of such studies. One group was from a university community, the other from the pharmaceutical industry. The differences between the two groups were correlated with their respective backgrounds. Both groups had favorable impressions about drug studies and investigators. Most were satisfied with the information given them about the nature and risks of the studies, but some believed that a written description of the study that they could consult at home would improve their understanding of the information. Financial reward was the primary reason given by both groups for volunteering, but the perceived risk of the study was the ultimate deciding factor. The volunteers disliked having their mobility restricted and for this reason might not be willing to participate in long-term studies, such as those formerly carried out in prisons. Alternative sources of volunteers for long-term studies will have to be found.
Serum Haemophilus influenzae Type b (HITB) anticapsular antibodies were induced in adult volunteers by feeding of either of two strains of a cross-reacting Escherichia coli 075:K100:H5. In all the fed volunteers colonization for a finite period lasting up to eight weeks occurred, without adventitious reactions. Nine of 14 normal volunteers and one of two volunteers previously immunized with the Type 6 H.influenzae polysaccharide responded with a greater than twofold increase in serum Type 6H. influenzae antibodies. These antibodies induced by Esch. coli were specific for the capsular polysaccharide and had bactericidal activity. The safety of this procedure, the comparable results in laboratory animals and the identification of other cross-reacting strains of Esch. coli with meningococcal and pneumococcal capsular polysaccharides suggest that colonization with these nonpathogenic organisms at birth may provide a general method of preventive immunization to diseases caused by encapsulated bacteria.
Double-blind studies were performed to compare the virulence of enterotoxigenic Escherichia coli with and without the fimbriate colonization factor antigen (CFA), using young healthy adults (mean age, 23 years) as volunteers. In the first study one group of volunteers ingested 1 X 10(6) E. coli H-10407, the CFA-positive strain, and another group ingested 1 X 10(6) E. coli H-10407-P, the CFA-negative spontaneous derivative of strain H-10407. The second study was similar except that the test strains were administered at a dose of 1 X 10(8) viable cells. Three parameters of infection were monitored: (i) diarrhea and associated symptoms; (ii) excretion pattern of test strains; and (iii) humoral antibody response to CFA, somatic antigen, and heat-labile enterotoxin. Significant signs of illness occurred only in six of seven volunteers who ingested E. coli H-10407 at a dose of 1 X 10(8). At both doses, E. coli H-10407-P appeared in the stool on day 1 postchallenge and disappeared by day 4. In contrast, strain H-10407 was persistently excreted from the first to the last day of the study. Also, only those volunteers in the H-10407 challenge groups (12 of 13 analyzed) responded with a fourfold antibody titer rise to CFA, somatic antigen, and/or heat-labile enterotoxin. No reversion of H-10407-P to H-10407 was detected.
The effects of experimentally induced rhinovirus and mycoplasmal respiratory tract infections on the pulmonary function of healthy, young, adult volunteers were investigated prospectively. Before inoculation, 12 volunteers were completely normal, whereas 9 had increased frequency dependence of compliance as their only abnormality of pulmonary function. Rhinovirus infection was induced in 8 of the completely normal volunteers, and 5 developed increased frequency dependence of compliance at the time of illness. These changes returned toward normal during the following 2 weeks and were not associated with concomitant changes in any other parameter of pulmonary function, including "closing volume". Three subjects with increased frequency dependence of compliance as their only abnormality before rhinovirus infection developed no significant change in dynamic compliance or any other abnormality in pulmonary function after infection. No changes in pulmonary function were detected in 3 volunteers with experimentally induced mycoplasmal infection. These finding suggest that although rhinovirus infections are associated primarily with upper respiratory illness, they can produce transient peripheral airway abnormalities in previously normal young adults; however, closing volumes, as well as routine pulmonary function studies, may not detect these changes.
Three human volunteers were successfully protected against sporozoite challenge by immunization with attenuated sporozoites of the Tamenie strain of Plasmodium falciparum from Ethiopia. The immunizing sporozoites were attenuated by exposing infected Anopheles stephensi mosquitos to X-rays at a dose of at least 120 Gy (12 000 rad). These irradiated, infected mosquitos were allowed to feed upon volunteers, thereby inoculating sporozoites into their blood stream. During the 10- to 38-week period of immunization, volunteers were exposed 6-8 times, at irregular intervals, to a total of 440-987 irradiated infected mosquitos. Protection against challenge by nonirradiated infected mosquitos lasted for at least 8 weeks, but not 16 weeks, after the last immunization with irradiated sporozoites. By contrast, volunteers who were exposed to a total of 200 or fewer irradiated infected mosquitos on 2-4 occasions were not protected upon challenge. Immunization by a sufficient number of irradiated mosquitos infected with the chloroquine-sensitive Tamenie strain from Ethiopia also protected against challenge with the chloroquine-resistant Marks strain of P. falciparum from Viet Nam. The results obtained in these studies suggest that immunization with attenuated sporozoites may be a useful method of protecting small groups of nonimmune individuals living in endemic areas. These findings should encourage further efforts to develop a sporozoite vaccine against human malaria.
Two aftercare programs using volunteers as therapists for former inpatients have been effective in reducing hospital readmissions. The volunteer therapists ensure that patients take medications, evaluate them for decompensation, help them find housing and jobs, and give them supportive counseling. In the first program the recidivism rate after one year for 36 chronic schizophrenic women was 11 per cent for the group treated by volunteers and 34 per cent for the control group receiving traditional aftercare. In the second program the recidivism rate after one year for 11 men and women with various types of schizophrenia was 9 per cent for the treatment group and 37 per cent for the control group.
This paper underscores the need for true sample selection before statistical inference of any value can be made. Its findings suggest that the sample selection strategy of symptomatic volunteers can produce samples of anxious subjects with remarkable demographic similarity across the country. Anxiety as a constitutional rather than pathognomonic symptom is illustrated by the heterogeneity of its psychometric evaluation in our volunteers. Expecting a drug to safely relieve the anxiety of all anxious symptomatic volunteers is akin to expecting a drug to safely relieve the headaches of all headache sufferers. We feel that careful psychodiagnosis remains the best sample selection strategy.
An extract and a filtrate prepared from feces of a child with mild gastroenteritis were shown by electron microscopy to contain numerous astrovirus particles and were given to eight volunteers by mouth. One subject developed diarrheal illness and concurrently shed large amounts of astrovirus in feces, and one other had mild constitutional symptoms with a lower level of virus shedding. Nine other volunteers were given fecal filtrate from the volunteer with diarrhea, and astrovirus shedding subsequently occurred in two of them. The syndrome accompanying virus shedding appeared distinct from that associated with the "W" agent in previous experiments. Thirteen of 16 astrovirus-inoculated subjects subsequently developed a rise in titer of the homologous antibody in serum. It was concluded that astrovirus causes a transmissible infection that is of low pathogenicity for adults. Immunofluorescence of human embryo kidney cells inoculated with astrovirus and shown by electron microscopy to contain 28 nm virus-like particles was used both to detect virus in feces and to assay astrovirus antibody.