Skip directly to search Skip directly to A to Z list Skip directly to page options Skip directly to site content

Volume 16, Number 2—February 2010

Volume 16, Number 2—February 2010   PDF Version [PDF - 4.33 MB - 195 pages]

Perspective

  • Effects of Coronavirus Infections in Children
    N. Principi et al.
       View Abstract

    The isolation of the coronavirus (CoV) identified as the cause of severe acute respiratory syndrome and the detection of 2 new human CoVs (HCoV-NL63 and HCoV-HKU1) have led to studies of the epidemiology and clinical and socioeconomic effects of infections caused by all HCoVs, including those known since the late 1960s (HCoV-229E and HCoV-OC43). HCoV infections can be associated with respiratory and extrarespiratory manifestations, including central nervous system involvement. Furthermore, unlike other RNA viruses, HCoVs can easily mutate and recombine when different strains infect the same cells and give rise to a novel virus with unpredictable host ranges and pathogenicity. Thus, circulating HCoVs should be closely monitored to detect the spread of particularly virulent strains in the community at an early stage and to facilitate the development of adequate preventive and therapeutic measures.

Research

  • Imported Methicillin-Resistant Staphylococcus aureus, Sweden PDF Version [PDF - 287 KB - 8 pages]
    M. Stenhem et al.
       View Abstract

    Countries such as Sweden that have a low prevalence of methicillin-resistant Staphylococcus aureus (MRSA) offer the opportunity to discern and study transmission of imported cases of MRSA. We analyzed 444 imported cases of MRSA acquisition reported in Sweden during 2000–2003. Risk for MRSA in returning travelers ranged from 0.1 (95% confidence interval [CI] 0.01–0.4) per 1 million travelers to Nordic countries to 59.4 (95% CI 44.5–79.3) per 1 million travelers to North Africa and the Middle East. Most imported cases (246, 55%) were healthcare acquired, but regions with the highest risk for MRSA in travelers showed a correlation with community acquisition (r = 0.81, p = 0.001). Characteristic differences in MRSA strains acquired were dependent on the region from which they originated and whether they were community or healthcare acquired. Knowledge of differences in transmission of MRSA may improve control measures against imported cases.

  • Medscape CME Activity
    Risk Factors for and Estimated Incidence of Community-associated Clostridium difficile Infection, North Carolina, USA PDF Version [PDF - 189 KB - 7 pages]
    P. K. Kutty et al.
       View Abstract

    We determined estimated incidence of and risk factors for community-associated Clostridium difficile infection (CA-CDI) among patients treated at 6 North Carolina hospitals. CA-CDI case-patients were defined as adults (>18 years of age) with a positive stool test result for C. difficile toxin and no hospitalization within the prior 8 weeks. CA-CDI incidence was 21 and 46 per 100,000 person-years in Veterans Affairs (VA) outpatients and Durham County populations, respectively. VA case-patients were more likely than controls to have received antimicrobial drugs (adjusted odds ratio [aOR] 17.8, 95% confidence interval [CI] 6.6–48] and to have had a recent outpatient visit (aOR 5.1, 95% CI 1.5–17.9). County case-patients were more likely than controls to have received antimicrobial drugs (aOR 9.1, 95% CI 2.9–28.9), to have gastroesophageal reflux disease (aOR 11.2, 95% CI 1.9–64.2), and to have cardiac failure (aOR 3.8, 95% CI 1.1–13.7). Risk factors for CA-CDI overlap with those for healthcare-associated infection.

  • Household Responses to Pandemic (H1N1) 2009–related School Closures, Perth, Western Australia PDF Version [PDF - 176 KB - 7 pages]
    P. V. Effler et al.
       View Abstract

    School closure is often purported to reduce influenza transmission, but little is known about its effect on families. We surveyed families affected by pandemic (H1N1) 2009–related school closures in Perth, Western Australia, Australia. Surveys were returned for 233 (58%) of 402 students. School closure was deemed appropriate by 110 parents (47%); however, 91 (45%) parents of 202 asymptomatic students reported taking >1 day off work to care for their child, and 71 (35%) had to make childcare arrangements because of the class closures. During the week, 172 (74%) students participated in activities outside the home on >1 occasion, resulting in an average of 3.7 out-of-home activities for each student. In our survey, activities outside the home were commonly reported by students affected by school closure, the effect on families was substantial, and parental opinion regarding school closures as a means to mitigate the outbreak of pandemic (H1N1) 2009 was divided.

  • Employment and Compliance with Pandemic Influenza Mitigation Recommendations PDF Version [PDF - 157 KB - 7 pages]
    K. D. Blake et al.
       View Abstract

    In the event of a serious pandemic influenza outbreak, businesses must play a key role in protecting employees' health and safety. With regard to pandemic influenza mitigation recommendations requiring social distancing, we examined whether some US employees would disproportionately fail to comply because of job insecurity and financial problems associated with missing work. We used the 2006 Harvard School of Public Health Pandemic Influenza Survey and multivariable logistic regression to determine whether employment characteristics such as inability to work from home, lack of pay when absent from work, and self-employment would be associated with less ability to comply with recommendations. We found that inability to work from home, lack of paid sick leave, and income are associated with working adults’ ability to comply and should be major targets for workplace interventions in the event of a serious outbreak.

  • Human Hendra Virus Encephalitis Associated with Equine Outbreak, Australia, 2008 PDF Version [PDF - 133 KB - 5 pages]
    E. G. Playford et al.
       View Abstract

    A recent Hendra virus outbreak at a veterinary clinic in Brisbane, Queensland, Australia, involved 5 equine and 2 human infections. In contrast to previous outbreaks, infected horses had predominantly encephalitic, rather than respiratory, signs. After an incubation period of 9–16 days, influenza-like illnesses developed in the 2 persons before progressing to encephalitis; 1 died. Both patients were given ribavirin. Basal serum and cerebrospinal fluid levels were 10–13 mg/L after intravenous administration and 6 mg/L after oral administration (isolate 90% inhibitory concentration 64 mg/L). Both patients were exposed to infected horses, 1 during the late incubation period in a horse. The attack rate for veterinary clinic staff exposed to infected horses was 10%. An isolate from this outbreak showed genetic heterogeneity with isolates from a concurrent, but geographically remote, outbreak and from previous outbreaks. Emergence of Hendra virus is a serious medical, veterinary, and public health challenge.

  • Cost-effectiveness of Pharmaceutical-based Pandemic Influenza Mitigation Strategies PDF Version [PDF - 282 KB - 7 pages]
    A. T. Newall et al.
       View Abstract

    We used a hybrid transmission and economic model to evaluate the relative merits of stockpiling antiviral drugs and vaccine for pandemic influenza mitigation. In the absence of any intervention, our base-case assumptions generated a population clinical attack rate of 31.1%. For at least some parameter values, population prepandemic vaccination strategies were effective at containing an outbreak of pandemic influenza until the arrival of a matched vaccine. Because of the uncertain nature of many parameters, we used a probabilistic approach to determine the most cost-effective strategies. At a willingness to pay of >A$24,000 per life-year saved, more than half the simulations showed that a prepandemic vaccination program combined with antiviral treatment was cost-effective in Australia.

  • Domestic Animals and Epidemiology of Visceral Leishmaniasis, Nepal PDF Version [PDF - 335 KB - 7 pages]
    N. R. Bhattarai et al.
       View Abstract

    On the Indian subcontinent, visceral leishmaniasis (VL) is considered an anthroponosis. To determine possible reasons for its persistence during interepidemic periods, we mapped Leishmania infections among healthy persons and animals in an area of active VL transmission in Nepal. During 4 months (September 2007–February 2008), blood was collected from persons, goats, cows, and buffaloes in 1 village. Leishmania infections were determined by using PCR. We found infections among persons (6.1%), cows (5%), buffaloes (4%), and goats (16%). Data were georeferenced and entered into a geographic information system. The bivariate K-function results indicated spatial clustering of Leishmania spp.–positive persons and domestic animals. Classification tree analysis determined that among several possible risk factors for Leishmania infection among persons, proximity of Leishmania spp.–positive goats ranked first. Although our data do not necessarily mean that goats constitute a reservoir host of L. donovani, these observations indicate the need for further investigation of goats’ possible role in VL transmission.

  • Investigating an Airborne Tularemia Outbreak, Germany PDF Version [PDF - 154 KB - 6 pages]
    A. M. Hauri et al.
       View Abstract

    In November 2005, an outbreak of tularemia occurred among 39 participants in a hare hunt in Hesse, Germany. Previously reported tularemia outbreaks in Germany dated back to the 1950s. We conducted a retrospective cohort study among participants and investigated the environment to identify risk factors for infection. Ten participants had serologic evidence of acute Francisella tularensis infection; 1 other participant died before laboratory confirmation was obtained. Presence within 5 meters of the place where disemboweled hares were rinsed with a water hose was the risk factor most strongly associated with infection (risk ratio 22.1; 95% confidence interval 13.2–154.3). Swabs taken at the game chamber and water samples were PCR negative for F. tularensis. Eleven of 14 hare parts showed low-level concentrations of F. tularensis, compatible with cross-contamination. More than half of case-patients may have acquired infection through inhalation of aerosolized droplets containing F. tularensis generated during rinsing of infected hares.

  • Statewide School-located Influenza Vaccination Program for Children 5–13 Years of Age, Hawaii, USA
    P. V. Effler et al.
       View Abstract

    New guidance recommends annual influenza vaccination for all children 5–18 years of age in the United States. During 2007–2008, Hawaii offered inactivated and live attenuated influenza vaccine at school-located clinics for grades kindergarten through 8. Most (90%) public and private schools participated, and 622 clinics were conducted at 340 schools. Of 132,775 children 5–13 years of age, 60,760 (46%) were vaccinated. The proportion vaccinated peaked at 54% for those 6 years of age and declined for older cohorts. More than 90% of schoolchildren transited the clinic in <10 minutes. A total of 16,920 staff-hours were expended; estimated cost per dose administered was $27 and included vaccine purchase and administration, health staffing resources, printing costs, data management, and promotion. This program demonstrates the feasibility of conducting mass school-located influenza vaccination programs in public and private schools statewide, as might be indicated to respond to pandemic influenza.

  • Epidemiology of Cryptococcus gattii, British Columbia, Canada, 1999–2007 PDF Version [PDF - 115 KB - 7 pages]
    E. Galanis et al.
    View Summary

    Incidence is high, but the predominant strain does not seem to cause greater illness or death than do other strains.

       View Abstract

    British Columbia, Canada, has the largest reported population of Cryptococcus gattii–infected persons worldwide. To assess the impact of illness, we retrospectively analyzed demographic and clinical features of reported cases, hospitalizations, and deaths during 1999–2007. A total of 218 cases were reported (average annual incidence 5.8 per million persons). Most persons who sought treatment had respiratory illness (76.6%) or lung cryptococcoma (75.4%). Persons without HIV/AIDS hospitalized with cryptococcosis were more likely than those with HIV/AIDS to be older and admitted for pulmonary cryptococcosis. The 19 (8.7%) persons who died were more likely to be older and to have central nervous system disease and infection from the VGIIb strain. Although incidence in British Columbia is high, the predominant strain (VGIIa) does not seem to cause greater illness or death than do other strains. Further studies are needed to explain host and strain characteristics for regional differences in populations affected and disease outcomes.

  • Tropheryma whipplei in Patients with Pneumonia PDF Version [PDF - 143 KB - 6 pages]
    S. Bousbia et al.
       View Abstract

    Tropheryma whipplei is the etiologic pathogenic agent of Whipple disease (WD), characterized by various clinical signs, such as diarrhea, weight loss, lymphadenopathy, and polyarthritis. PCR-based methods for diagnosis of WD have been developed. T. whipplei has been identified in saliva and stool samples from patients with WD and from healthy persons. T. whipplei DNA has also been found in bronchoalveolar lavage (BAL) samples of a child with pneumonia. We detected DNA of T. whipplei in 6 (3%) of 210 BAL samples collected in intensive care units by using 16S rDNA and specific quantitative PCR. We identified 4 novel genotypes of T. whipplei. In 1 case, T. whipplei was the only bacterium; in 4 others, it was associated with buccal flora. We suggest that T. whipplei should be investigated as an etiologic agent of pneumonia.

  • Emergence of Increased Resistance and Extensively Drug-Resistant Tuberculosis Despite Treatment Adherence, South Africa PDF Version [PDF - 175 KB - 9 pages]
    A. D. Calver et al.
       View Abstract

    We investigated the emergence and evolution of drug-resistant tuberculosis (TB) in an HIV co-infected population at a South African gold mine with a well-functioning TB control program. Of 128 patients with drug-resistant TB diagnosed during January 2003–November 2005, a total of 77 had multidrug-resistant (MDR) TB, 26 had pre–extensively drug-resistant TB (XDR TB), and 5 had XDR TB. Genotyping suggested ongoing transmission of drug-resistant TB, and contact tracing among case-patients in the largest cluster demonstrated multiple possible points of contact. Phylogenetic analysis demonstrated stepwise evolution of drug resistance, despite stringent treatment adherence. These findings suggested that existing TB control measures were inadequate to control the spread of drug-resistant TB in this HIV co-infected population. Diagnosis delay and inappropriate therapy facilitated disease transmission and drug-resistance. These data call for improved infection control measures, implementation of rapid diagnostics, enhanced active screening strategies, and pharmacokinetic studies to determine optimal dosages and treatment regimens.

  • Associations between Mycobacterium tuberculosis Strains and Phenotypes PDF Version [PDF - 341 KB - 3 pages]
    T. Brown et al.
       View Abstract

    To inform development of tuberculosis (TB) control strategies, we characterized a total of 2,261 Mycobacterium tuberculosis complex isolates by using multiple phenotypic and molecular markers, including polymorphisms in repetitive sequences (spoligotyping and variable-number tandem repeats [VNTRs]) and large sequence and single-nucleotide polymorphisms. The Beijing family was strongly associated with multidrug resistance (p = 0.0001), and VNTR allelic variants showed strong associations with spoligotyping families: >5 copies at exact tandem repeat (ETR) A, >2 at mycobacterial interspersed repetitive unit 24, and >3 at ETR-B associated with the East African–Indian and M. bovis strains. All M. tuberculosis isolates were differentiated into 4 major lineages, and a maximum parsimony tree was constructed suggesting a more complex phylogeny for M. africanum. These findings can be used as a model of pathogen global diversity.

Historical Review

  • New Hypothesis for Cause of Epidemic among Native Americans, New England, 1616–1619
    J. S. Marr and J. T. Cathey
       View Abstract

    In the years before English settlers established the Plymouth colony (1616–1619), most Native Americans living on the southeastern coast of present-day Massachusetts died from a mysterious disease. Classic explanations have included yellow fever, smallpox, and plague. Chickenpox and trichinosis are among more recent proposals. We suggest an additional candidate: leptospirosis complicated by Weil syndrome. Rodent reservoirs from European ships infected indigenous reservoirs and contaminated land and fresh water. Local ecology and high-risk quotidian practices of the native population favored exposure and were not shared by Europeans. Reduction of the population may have been incremental, episodic, and continuous; local customs continuously exposed this population to hyperendemic leptospiral infection over months or years, and only a fraction survived. Previous proposals do not adequately account for signature signs (epistaxis, jaundice) and do not consider customs that may have been instrumental to the near annihilation of Native Americans, which facilitated successful colonization of the Massachusetts Bay area.

Dispatches

Commentaries

Another Dimension

Letters

About the Cover

Etymologia

TOP