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Karin Leder

Publications and source records attributed to Karin Leder.

14 recordsLinked to original sources
PubMed2006

Illness in travelers visiting friends and relatives: a review of the GeoSentinel Surveillance Network.

Travelers returning to their country of origin to visit friends and relatives (VFRs) have increased risk of travel-related health problems. We examined GeoSentinel data to compare travel characteristics and illnesses acquired by 3 groups of travelers to low-income countries: VFRs who had originally been immigrants (immigrant VFRs), VFRs who had not originally been immigrants (traveler VFRs), and tourist travelers. Immigrant VFRs were predominantly male, had a higher mean age, and disproportionately required treatment as inpatients. Only 16% of immigrant VFRs sought pretravel medical advice. Proportionately more immigrant VFRs visited sub-Saharan Africa and traveled for >30 days, whereas tourist travelers more often traveled to Asia. Systemic febrile illnesses (including malaria), nondiarrheal intestinal parasitic infections, respiratory syndromes, tuberculosis, and sexually transmitted diseases were more commonly diagnosed among immigrant VFRs, whereas acute diarrhea was comparatively less frequent. Immigrant VFRs and traveler VFRs had different demographic characteristics and types of travel-related illnesses. A greater proportion of immigrant VFRs presented with serious, potentially preventable travel-related illnesses than did tourist travelers.

Adolescent↗
PubMed2006

Medically evaluated psychological and physical health of Australian Gulf War veterans with chronic fatigue.

OBJECTIVE: The aim of this study was to evaluate fatigue in Australian Gulf War veterans and a military comparison group according to the 1994 chronic fatigue syndrome (CFS) definition and investigate the relation with exposures. METHODS: Comprehensive medical, psychological and reported exposure assessments of 1,456 veterans and 1,588 comparison group in a cross-sectional study. RESULTS: More Gulf War veterans had fatigue at all levels than did the military comparison group. The findings may be at least partly explained as an "active-deployment effect." The odds ratios increased with increasing clinical evaluation of the nature of the fatigue, even after adjustment for current psychiatric disorders in addition to other possible confounding factors. CONCLUSION: Medically unexplained chronic fatigue was more common, but not more disabling, in veterans than in the comparison group, but veterans with unexplained chronic fatigue had poorer health than veterans without. Within both populations, CFS is uncommon and at a similar level to the general community.

Activities of Daily Living↗
PubMed2005

No correlation between clinical symptoms and Blastocystis hominis in immunocompetent individuals.

UNLABELLED: Abstract Background and Aim: Previous reports regarding the clinical significance and pathogenicity of Blastocystis hominis have been contradictory. The aim of this study was to examine the association between Blastocystis and gastrointestinal symptoms in immunocompetent individuals. METHODS: We monitored over 2800 healthy people for a period of 15 months, and took stool specimens during both asymptomatic periods and during periods of gastrointestinal symptoms. RESULTS: After exclusion of individuals who had simultaneous identification of other fecal pathogens, we compared the proportions of asymptomatic versus symptomatic individuals positive for Blastocystis and found no significant difference (P = 0.5). Symptom status did not correlate with parasite abundance. We found that some individuals were likely to have Blastocystis detected during both asymptomatic and symptomatic periods, possibly suggesting carriage of the organism. CONCLUSION: In conclusion, we found no correlation between clinical symptoms and the presence or absence of Blastocystis among this healthy cohort.

Adolescent↗
PubMed2005

Pathogens causing community gastroenteritis in Australia.

BACKGROUND AND AIM: Many individuals with gastrointestinal symptoms do not seek medical attention and so there is little known about the pathogens involved in most cases of community gastroenteritis. We aimed to identify the pathogens responsible for community gastroenteritis and to examine the associated symptoms. METHODS: In a prospective study of 2811 subjects over 15 months, fecal pathogens were examined following highly credible gastroenteritis (HCG) events. The population consisted of family units of at least two children (< or =15 years-old) and two adults each. Fecal samples were tested for a range of bacterial, viral and protozoal pathogens. Gastroenteric episode duration and symptoms such as vomiting, nausea and diarrhea were measured. RESULTS: One or more pathogens were identified in 198 of a total 791 specimens collected. Pathogens detected most often were Norovirus virus (10.7%), pathogenic E. coli (6.7%), Campylobacter spp. (3.0%) and Giardia sp. (2.5%). Children were more prone than adults to all the pathogens tested, except E. coli. Children infected with Campylobacter were 8.3 times more likely (95% CI: 2.7-25.4) to have a longer duration of diarrhea than children with Norovirus (P < 0.001). Similarly, children infected with E. coli had increased persistence of diarrhea compared to Norovirus (OR = 3.5; 95% CI: 1.3-9.5; P = 0.02). Infection with Norovirus in children meant greater persistence of vomiting symptoms than infection with Campylobacter (P = 0.005), E. coli (P = 0.03), or if no pathogen was identified (P = 0.004). Adults usually vomited for fewer days than children while duration of diarrhea was similar to children. CONCLUSIONS: Many of the pathogens responsible for cases of gastroenteritis in the Australian community are likely to go undetected by current surveillance systems and routine clinical practice.

Adolescent↗
PubMed2004

Malaria in travelers: a review of the GeoSentinel surveillance network.

BACKGROUND: Malaria is a common and important infection in travelers. METHODS: We have examined data reported to the GeoSentinel surveillance network to highlight characteristics of malaria in travelers. RESULTS: A total of 1140 malaria cases were reported (60% of cases were due to Plasmodium falciparum, 24% were due to Plasmodium vivax). Male subjects constituted 69% of the study population. The median duration of travel was 34 days; however, 37% of subjects had a travel duration of < or =4 weeks. The majority of travellers did not have a pretravel encounter with a health care provider. Most cases occurred in travelers (39%) or immigrants/refugees (38%). The most common reasons for travel were to visit friends/relatives (35%) or for tourism (26%). Three-quarters of infections were acquired in sub-Saharan Africa. Severe and/or complicated malaria occurred in 33 cases, with 3 deaths. Compared with others in the GeoSentinel database, patients with malaria had traveled to sub-Saharan Africa more often, were more commonly visiting friends/relatives, had traveled for longer periods, presented sooner after return, were more likely to have a fever at presentation, and were less likely to have had a pretravel encounter. In contrast to immigrants and visitors of friends or relatives, a higher proportion (73%) of the missionary/volunteer group who developed malaria had a pretravel encounter with a health care provider. Travel to sub-Saharan Africa and Oceania was associated with the greatest relative risk of acquiring malaria. CONCLUSIONS: We have used a global database to identify patient and travel characteristics associated with malaria acquisition and characterized differences in patient type, destinations visited, travel duration, and malaria species acquired.

Africa↗
PubMed2004

Food safety in family homes in Melbourne, Australia.

Poor food handling practices in the home are a likely cause of gastroenteritis. This study examined how often reported practices in Australian homes met public health food safety recommendations. During 1998 in Melbourne, Australia, food handling and food storage questionnaires were completed by an adult member in 524 and 515 families, respectively. Each family consisted of at least two adults and two children. Respondents were surveyed regarding washing of hands, cutting boards, and fresh produce; use of kitchen cloths; egg storage; where cooked foods were cooled; the duration before refrigeration of cooked foods; where food types were positioned in the refrigerator; and the method of thawing chicken. Nearly every household reported handling food in a way that could cause food to become contaminated. Overall, 99.0% of respondents reported some form of mishandling, which encompassed 70.3% who handled food preparation surfaces poorly, 46.6% who did not wash their hands appropriately or in a timely manner, 41.7% who mishandled raw foods, and 70.1% who mishandled cooked foods. Food was inappropriately located in the refrigerator by 81.2%, and chicken was thawed using unsafe means by 76.3% of respondents. People preparing food in the home need to be reminded of the increased risk of disease that can arise from poor food handling practices.

Adolescent↗
PubMed2003

Respiratory tract infections in travelers: a review of the GeoSentinel surveillance network.

Respiratory tract infections are common in travelers, and improving our knowledge of risk factors associated with specific types of respiratory infections should enable implementation of better preventive strategies. Data collected by the GeoSentinel surveillance network were analyzed, and the most significant predictors for developing specific categories of respiratory infections while abroad were age, sex, season of travel, trip duration, and reason for travel. In particular, influenza was associated with travel to the Northern Hemisphere during the period of December through February, travel involving visits to friends or relatives, and trip duration of >30 days. Lower respiratory tract infections were associated with male sex and increasing age. Knowledge of the respiratory tract infections that occur in specific groups of travelers allows for the development of targeted pretravel preventive strategies to high-risk groups.

Adolescent↗
PubMed2003

A community-based study of respiratory episodes in Melbourne, Australia.

OBJECTIVE: To provide recent data regarding the epidemiology of community-based respiratory infections in Australia. METHODS: A longitudinal study between 1997-99 involving collection of a health diary from 600 families in Melbourne. RESULTS: More than 80% of study participants reported at least one respiratory episode over 15 months. An average of 2.2 respiratory episodes per person per year was reported, with a mean episode duration of 6.3 days. On average, subjects were symptomatic for 4.2% of the study days. Compared with other age groups, children aged less than two years were most likely to have at least one respiratory episode, a greater number of episodes per person and the longest episode duration (6.8 days). Approximately, one in three (28.7%) respiratory episodes were associated with a doctor's visit, and one in four (23%) necessitated time off school or work. Exposure to other people with respiratory symptoms was commonly reported. CONCLUSIONS: Respiratory infections are common, cause a significant amount of morbidity, and are major contributors to the total community health burden. IMPLICATIONS: The direct and indirect costs of respiratory infections to the community are substantial.

Adolescent↗
PubMed2002

The effect of age on immunologic response to recombinant hepatitis B vaccine: a meta-analysis.

Hepatitis B vaccine is a key tool for the prevention of hepatitis B infection. Age-associated changes in immune function may contribute to decreased vaccine efficacy in older individuals, although research related to this topic has yielded contradictory findings. We performed a meta-analysis of 24 published trials and studies that evaluated the association of age with response to hepatitis B vaccine, using a random-effects model. Pooling of study results suggested a significantly increased risk of nonresponse to hepatitis B vaccine among older individuals (relative risk [RR], 1.76; 95% confidence interval [CI], 1.48-2.10). An elevated risk of nonresponse persisted even after exclusion of poor-quality studies (RR, 1.63; 95% CI, 1.23-2.15) and adjustment for publication bias (RR, 1.52; 95% CI, 1.26-1.83), and it was present even when "older" individuals were defined as being as young as 30 years. These findings have important implications for individuals at risk for hepatitis B infection, including health care workers and travelers.

Adult↗
PubMedDate not supplied

Illness in returned travelers and immigrants/refugees: the 6-year experience of two Australian infectious diseases units.

BACKGROUND: Data comparing returned travelers and immigrants/refugees managed in a hospital setting is lacking. METHODS: We prospectively collected data on 1,106 patients with an illness likely acquired overseas who presented to two hospital-based Australian infectious diseases units over a 6-year period. RESULTS: Eighty-three percent of patients were travelers and 17% immigrants/refugees. In travelers, malaria (19%), gastroenteritis/diarrhea (15%), and upper respiratory tract infection (URTI) (7%) were the most common diagnoses. When compared with immigrants/refugees, travelers were significantly more likely to be diagnosed with gastroenteritis/diarrhea [odds ratio (OR) 8], malaria (OR 7), pneumonia (OR 6), URTI (OR 3), skin infection, dengue fever, typhoid/paratyphoid fever, influenza, and rickettsial disease. They were significantly less likely to be diagnosed with leprosy (OR 0.03), chronic hepatitis (OR 0.04), tuberculosis (OR 0.05), schistosomiasis (OR 0.3), and helminthic infection (OR 0.3). In addition, travelers were more likely to present within 1 month of entry into Australia (OR 96), and have fever (OR 8), skin (OR 6), gastrointestinal (OR 5), or neurological symptoms (OR 5) but were less likely to be asymptomatic (OR 0.1) or have anaemia (OR 0.4) or eosinophilia (OR 0.3). Diseases in travelers were more likely to have been acquired via a vector (OR 13) or food and water (OR 4), and less likely to have been acquired via the respiratory (OR 0.2) or skin (OR 0.6) routes. We also found that travel destination and classification of traveler can significantly influence the likelihood of a specific diagnosis in travelers. Six percent of travelers developed a potentially vaccine-preventable disease, with failure to vaccinate occurring in 31% of these cases in the pretravel medical consultation. CONCLUSIONS: There are important differences in the spectrum of illness, clinical features, and mode of disease transmission between returned travelers and immigrants/refugees presenting to hospital-based Australian infectious diseases units with an illness acquired overseas.

Adolescent↗
PubMedDate not supplied

Imported Plasmodium vivax malaria: demographic and clinical features in nonimmune travelers.

BACKGROUND: Imported malaria is an important problem in nonendemic countries due to increasing travel to and immigration from malaria-endemic countries. Plasmodium vivax malaria is relatively common in travelers but there are few published data regarding the outcome of P. vivax malaria in this group. METHODS: We analyzed 209 cases of P. vivax malaria that were reported to the GeoSentinel network and the VIDS database, Royal Melbourne Hospital. Analyses were performed on data including demographics, pretravel encounter, antimalarial prophylaxis, exposure history, type of travel, countries of recent and past travel, clinical presentation, treatment, outcome and final diagnoses. RESULTS: The majority of patients were travelers (61%), followed by expatriates (13%) and recent immigrants or foreign visitors (12%). Recent travel to Oceania, sub-Saharan Africa, and South and Central America was significantly more likely to be associated with P. vivax malaria than travel to all other regions. The clinical presentation of P. vivax malaria acquired in the Pacific region is indistinguishable from infection with P. falciparum. The use of chloroquine prophylaxis did not prolong the incubation period. Relapse of infection was not infrequent, and the only significant predictor of relapse was travel to Papua New Guinea (PNG), regardless of primaquine dose. Travelers returning from PNG were eight times more likely to relapse after primaquine treatment compared to travelers with P. vivax malaria acquired elsewhere. CONCLUSIONS: We have presented details of the epidemiology, clinical presentation and management of infection with P. vivax malaria in travelers. P. vivax malaria is an important cause of morbidity in travelers, and relapse following primaquine treatment is especially problematic with P. vivax malaria acquired in PNG.

Adolescent↗
PubMedDate not supplied

Water and the environment: a natural resource or a limited luxury?

The risk of contamination of drinking water supplies with microbial pathogens is minimised by modern approaches to water management, but continues to be the major public health concern. Chemical contaminants usually pose little health risk except at very high levels, but debate continues over the potential adverse health effects of low-level, chronic exposure to compounds such as disinfection byproducts. Recreational water contact can be associated with adverse health outcomes either from microbial infections or exposure to cyanobacterial toxins. Environmental issues such as increasing salinity and global warming are likely to affect the sustainability of our current drinking water supplies and increase the threat of waterborne disease outbreaks. New technologies, use of alternative water sources, such as rainwater tanks, water reuse and restrictions will undoubtedly be part of the solution to our diminishing water resources, but have the potential to introduce new health threats.

Australia↗