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Volume 15, Number 8—August 2009
Volume 15, Number 8—August 2009 PDF Version [PDF - 6.00 MB - 187 pages]
Reemerging Rabies and Lack of Systemic Surveillance in People’s Republic of China
PDF Version [PDF - 497 KB - 6 pages]
X. Wu et al.View Abstract
Rabies is a reemerging disease in China. The high incidence of rabies leads to numerous concerns: a potential carrier-dog phenomenon, undocumented transmission of rabies virus from wildlife to dogs, counterfeit vaccines, vaccine mismatching, and seroconversion testing in patients after their completion of postexposure prophylaxis (PEP). These concerns are all scientifically arguable given a modern understanding of rabies. Rabies reemerges periodically in China because of high dog population density and low vaccination coverage in dogs. Mass vaccination campaigns rather than depopulation of dogs should be a long-term goal for rabies control. Seroconversion testing after vaccination is not necessary in either humans or animals. Human PEP should be initiated on the basis of diagnosis of biting animals. Reliable national systemic surveillance of rabies-related human deaths and of animal rabies prevalence is urgently needed. A laboratory diagnosis–based epidemiologic surveillance system can provide substantial information about disease transmission and effective prevention strategies.
Use of Revised International Health Regulations during Influenza A (H1N1) Epidemic, 2009
PDF Version [PDF - 401 KB - 6 pages]
R. KatzView Abstract
Strong international health agreements and good planning created a structure and common procedure for nations involved in detection and evaluation of the emergence of influenza A (H1N1). This report describes a timeline of events that led to the determination of the epidemic as a public health emergency of international concern, following the agreed-upon procedures of the International Health Regulations. These events illustrate the need for sound international health agreements and should be a call to action for all nations to implement these agreements to the best of their abilities.
Response to Imported Case of Marburg Hemorrhagic Fever, the Netherlands
PDF Version [PDF - 472 KB - 5 pages]
A. Timen et al.View Abstract
On July 10, 2008, Marburg hemorrhagic fever was confirmed in a Dutch patient who had vacationed recently in Uganda. Exposure most likely occurred in the Python Cave (Maramagambo Forest), which harbors bat species that elsewhere in Africa have been found positive for Marburg virus. A multidisciplinary response team was convened to perform a structured risk assessment, perform risk classification of contacts, issue guidelines for follow-up, provide information, and monitor the crisis response. In total, 130 contacts were identified (66 classified as high risk and 64 as low risk) and monitored for 21 days after their last possible exposure. The case raised questions specific to international travel, postexposure prophylaxis for Marburg virus, and laboratory testing of contacts with fever. We present lessons learned and results of the follow-up serosurvey of contacts and focus on factors that prevented overreaction during an event with a high public health impact.
Tactics and Economics of Wildlife Oral Rabies Vaccination, Canada and the United States
PDF Version [PDF - 759 KB - 9 pages]
R. T. Sterner et al.View Abstract
Progressive elimination of rabies in wildlife has been a general strategy in Canada and the United States; common campaign tactics are trap–vaccinate–release (TVR), point infection control (PIC), and oral rabies vaccination (ORV). TVR and PIC are labor intensive and the most expensive tactics per unit area (≈$616/km2 [in 2008 Can$, converted from the reported $450/km2 in 1991 Can$] and ≈$612/km2 [$500/km2 in 1999 Can$], respectively), but these tactics have proven crucial to elimination of raccoon rabies in Canada and to maintenance of ORV zones for preventing the spread of raccoon rabies in the United States. Economic assessments have shown that during rabies epizootics, costs of human postexposure prophylaxis, pet vaccination, public health, and animal control spike. Modeling studies, involving diverse assumptions, have shown that ORV programs can be cost-efficient and yield benefit:cost ratios >1.0.
Spread of Cryptococcus gattii into Pacific Northwest Region of the United States
PDF Version [PDF - 586 KB - 7 pages]
K. Datta et al.View Abstract
Cryptococcus gattii has emerged as a human and animal pathogen in the Pacific Northwest. First recognized on Vancouver Island, British Columbia, Canada, it now involves mainland British Columbia, and Washington and Oregon in the United States. In Canada, the incidence of disease has been one of the highest worldwide. In the United States, lack of cryptococcal species identification and case surveillance limit our knowledge of C. gattii epidemiology. Infections in the Pacific Northwest are caused by multiple genotypes, but the major strain is genetically novel and may have emerged recently in association with unique mating or environmental changes. C. gattii disease affects immunocompromised and immunocompetent persons, causing substantial illness and death. Successful management requires an aggressive medical and surgical approach and consideration of potentially variable antifungal drug susceptibilities. We summarize the study results of a group of investigators and review current knowledge with the goal of increasing awareness and highlighting areas where further knowledge is required.
Molecular Epidemiology of Rabies in Southern People’s Republic of China
PDF Version [PDF - 511 KB - 7 pages]
X. Tao et al.View Abstract
In recent years, the number of human rabies cases in the People’s Republic of China has increased during severe epidemics in 3 southern provinces (Guizhou, Guangxi, and Hunan). To analyze the causes of the high incidence of human rabies in this region, during 2005–2007, we collected 2,887 brain specimens from apparently healthy domestic dogs used for meat consumption in restaurants, 4 specimens from suspected rabid dogs, and 3 from humans with rabies in the 3 provinces. Partial nucleoprotein gene sequences were obtained from rabies-positive specimens. Phylogenetic relationships and distribution of viruses were determined. We infer that the spread of rabies viruses from high-incidence regions, particularly by long-distance movement or transprovincial translocation of dogs caused by human-related activities, may be 1 cause of the recent massive human rabies epidemics in southern China.
Serologic Evidence of Frequent Human Infection with WU and KI Polyomaviruses
PDF Version [PDF - 664 KB - 7 pages]
N. L. Nguyen et al.View Abstract
WU polyomavirus (WUPyV) and KI polyomavirus (KIPyV) are novel human polyomaviruses. They were originally identified in human respiratory secretions, but the extent of human infection caused by these viruses has not been described to date. To determine the seroepidemiology of WUPyV and KIpyIV, we used an ELISA to screen serum samples from 419 patients at the St. Louis Children’s Hospital and Barnes-Jewish Hospital during 2007–2008. The age-stratified deidentified samples were examined for antibodies to the major capsid proteins of WUPyV and KIPyV. Seropositivity for each virus was similar; antibody levels were high in the youngest age group (<6 months), decreased to a nadir in the next age group (6 to <12 months), and then steadily increased with subsequent age groups, eventually reaching a plateau of ≈80% for WUPyV and ≈70% for KIPyV. These results demonstrate that both KIPyV and WUPyV cause widespread infection in the human population.
Bordetella pertussis Strains with Increased Toxin Production Associated with Pertussis Resurgence
PDF Version [PDF - 688 KB - 8 pages]
F. R. Mooi et al.View Abstract
Before childhood vaccination was introduced in the 1940s, pertussis was a major cause of infant death worldwide. Widespread vaccination of children succeeded in reducing illness and death. In the 1990s, a resurgence of pertussis was observed in a number of countries with highly vaccinated populations, and pertussis has become the most prevalent vaccine-preventable disease in industrialized countries. We present evidence that in the Netherlands the dramatic increase in pertussis is temporally associated with the emergence of Bordetella pertussis strains carrying a novel allele for the pertussis toxin promoter, which confers increased pertussis toxin (Ptx) production. Epidemiologic data suggest that these strains are more virulent in humans. We discuss changes in the ecology of B. pertussis that may have driven this adaptation. Our results underline the importance of Ptx in transmission, suggest that vaccination may select for increased virulence, and indicate ways to control pertussis more effectively.
Transgenic Mice Expressing Porcine Prion Protein Resistant to Classical Scrapie but Susceptible to Sheep Bovine Spongiform Encephalopathy and Atypical Scrapie
PDF Version [PDF - 496 KB - 8 pages]
J. Espinosa et al.View Abstract
How susceptible pigs are to infection with sheep prions is unknown. We show, through transmission experiments in transgenic mice expressing porcine prion protein (PrP), that the susceptibility of this mouse model to bovine spongiform encephalopathy (BSE) can be enhanced after its passage in ARQ sheep, indicating that the pathogenicity of the BSE agent is modified after passage in sheep. Transgenic mice expressing porcine PrP were, nevertheless, completely resistant to infection with a broad panel of classical scrapie isolates from different sheep PrP genotypes and with different biochemical characteristics. The atypical (Nor98 like) isolate (SC-PS152) was the only scrapie isolate capable of transmission in these mice, although with a marked transmission barrier. Unexpectedly, the atypical scrapie agent appeared to undergo a strain phenotype shift upon transmission to porcine-PrP transgenic mice and acquired new strain properties, suggesting that atypical scrapie agent may exhibit different phenotypes depending on the host cellular PrP or other genetic factors.
Slave Trade and Hepatitis B Virus Genotypes and Subgenotypes in Haiti and Africa
PDF Version [PDF - 565 KB - 7 pages]
I. E. Andernach et al.View SummaryView Abstract
The spread of genotype E in Africa occurred after the end of the transatlantic slave trade.
In Haiti, >90% of the population descended from African slaves. Of 7,147 Haitian pregnant women sampled, 44% of hepatitis B virus (HBV) infections were caused by genotype A1, which today is found mainly in eastern Africa. Twenty percent belong to a rare subgenotype, A5, which has been found only in the former Bight of Benin, a former primary slave trading post. Haitian A subgenotypes appear to have separated early from the African subgenotypes; the most prevalent genotype and subgenotype in West Africa today (E and A3, respectively) are rare in Haiti. This difference indicates that the dominant subgenotypes in Africa emerged in the general population only after the slave trade and explains the low genetic diversity of genotype E. The high prevalence of HBV genotype E in much of Africa further suggests that HBV hyperendemicity is a recent phenomenon, probably resulting from extensive use of unsafe needles.
Recurrent Zoonotic Transmission of Nipah Virus into Humans, Bangladesh, 2001–2007
PDF Version [PDF - 563 KB - 7 pages]
S. P. Luby et al.View Abstract
Human Nipah outbreaks recur in a specific region and time of year in Bangladesh. Fruit bats are the reservoir host for Nipah virus. We identified 23 introductions of Nipah virus into human populations in central and northwestern Bangladesh from 2001 through 2007. Ten introductions affected multiple persons (median 10). Illness onset occurred from December through May but not every year. We identified 122 cases of human Nipah infection. The mean age of case-patients was 27 years; 87 (71%) died. In 62 (51%) Nipah virus–infected patients, illness developed 5–15 days after close contact with another Nipah case-patient. Nine (7%) Nipah case-patients transmitted virus to others. Nipah case-patients who had difficulty breathing were more likely than those without respiratory difficulty to transmit Nipah (12% vs. 0%, p = 0.03). Although a small minority of infected patients transmit Nipah virus, more than half of identified cases result from person-to-person transmission. Interventions to prevent virus transmission from bats to humans and from person to person are needed.
Medscape CME Activity
National Outbreak of Acanthamoeba Keratitis Associated with Use of a Contact Lens Solution, United States PDF Version [PDF - 633 KB - 7 pages]J. R. Verani et al.View Abstract
An outbreak of Acanthamoeba keratitis, a rare, potentially blinding, corneal infection, was detected in the United States in 2007; cases had been increasing since 2004. A case–control study was conducted to investigate the outbreak. We interviewed 105 case-patients from 30 states and 184 controls matched geographically and by contact lens use. Available contact lenses, cases, solutions, and corneal specimens from case-patients were cultured and tested by molecular methods. In multivariate analyses, case-patients had significantly greater odds of having used Advanced Medical Optics Complete Moisture Plus (AMOCMP) solution (odds ratio 16.9, 95% confidence interval 4.8–59.5). AMOCMP manufacturing lot information was available for 22 case-patients, but none of the lots were identical. Three unopened bottles of AMOCMP tested negative for Acanthamoeba spp. Our findings suggest that the solution was not intrinsically contaminated and that its anti-Acanthamoeba efficacy was insufficient. Premarket standardized testing of contact lens solutions for activity against Acanthamoeba spp. is warranted.
Entomologic and Virologic Investigation of Chikungunya, Singapore
PDF Version [PDF - 570 KB - 7 pages]
L. Ng et al.View Abstract
Local transmission of chikungunya, a debilitating mosquito-borne viral disease, was first reported in Singapore in January 2008. After 3 months of absence, locally acquired Chikungunya cases resurfaced in May 2008, causing an outbreak that resulted in a total of 231 cases by September 2008. The circulating viruses were related to East, Central, and South African genotypes that emerged in the Indian Ocean region in 2005. The first local outbreak was due to a wild-type virus (alanine at codon 226 of the envelope 1 gene) and occurred in an area where Aedes aegypti mosquitoes were the primary vector. Strains isolated during subsequent outbreaks showed alanine to valine substitution (A226V) and largely spread in areas predominated by Ae. albopictus mosquitoes. These findings led to a revision of the current vector control strategy in Singapore. This report highlights the use of entomologic and virologic data to assist in the control of chikungunya in disease-endemic areas.
Reproducibility of Serologic Assays for Influenza Virus A (H5N1)
PDF Version [PDF - 580 KB - 10 pages]
I. Stephenson et al.View Abstract
Hemagglutination-inhibition (HI) and neutralization are used to evaluate vaccines against influenza virus A (H5N1); however, poor standardization leads to interlaboratory variation of results. A candidate antibody standard (07/150) was prepared from pooled plasma of persons given clade 1 A/Vietnam/1194/2004 vaccine. To test human and sheep antiserum, 15 laboratories used HI and neutralization and reassortant A/Vietnam/1194/2004, A/turkey/Turkey/1/2005 (clade 2.2), and A/Anhui/1/2005 (clade 2.3.4) viruses. Interlaboratory variation was observed for both assays, but when titers were expressed relative to 07/150, overall percentage geometric coefficient of variation for A/Vietnam/1194/2004 was reduced from 125% to 61% for HI and from 183% to 81% for neutralization. Lack of reduced variability to clade 2 antigens suggested the need for clade-specific standards. Sheep antiserum as a standard did not reliably reduce variability. The World Health Organization has established 07/150 as an international standard for antibody to clade 1 subtype H5 and has an assigned potency of 1,000 IU/ampoule.
Increase in Pneumococcus Macrolide Resistance, United States
PDF Version [PDF - 440 KB - 5 pages]
S. G. Jenkins and D. J. FarrellView SummaryView Abstract
During year 6 of the study, the incidence rate rose from ≈30% to 35.3%.
During year 6 (2005–2006) of the Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin surveillance study, 6,747 Streptococcus pneumoniae isolates were collected at 119 centers. The susceptibility of these isolates to macrolides was compared with data from previous years. Macrolide resistance increased significantly in year 6 (35.3%) from the stable rate of ≈30% for the previous 3 years (p<0.0001). Macrolide resistance increased in all regions of the United States and for all patient age groups. Rates were highest in the south and for children 0–2 years of age. Lower-level efflux [mef(A)]–mediated macrolide resistance decreased in prevalence to ≈50%, and highly resistant [erm(B) + mef(A)] strains increased to 25%. Telithromycin and levofloxacin susceptibility rates were >99% and >98%, respectively, irrespective of genotype. Pneumococcal macrolide resistance in the United States showed its first significant increase since 2000. High-level macrolide resistance is also increasing.
Dengue 1 Virus and Dengue Hemorrhagic Fever, French Polynesia, 2001
PDF Version [PDF - 584 KB - 6 pages]
B. Hubert and S. B. HalsteadView SummaryView Abstract
Severe disease was more likely after an infection sequence of DENV-2 followed by DENV-1.
An epidemic of dengue 1 virus (DENV-1) occurred in French Polynesia in 2001, 4 years after a DENV-2 epidemic that ended in 1997. Surveillance data from hospitalized case-patients showed that case-patients with dengue hemorrhagic fever (DHF) exhibited a bimodal age distribution with 1 peak among infants 6–10 months of age and a second peak at 4–11 years of age. The relative risk of DHF developing in children born before rather than after the DENV-2 epidemic was 186 (95% confidence interval 26–1,324). Among children born toward the end of the DENV-2 epidemic, a strong temporal association was found between the month of birth and the risk of being hospitalized for DHF. This study documents epidemic pathogenicity associated with the sequence of DENV-2 infection followed by DENV-1 infection.
Strategy to Enhance Influenza Surveillance Worldwide
PDF Version [PDF - 569 KB - 8 pages]
J. R. Ortiz et al.View Abstract
The emergence of a novel strain of influenza virus A (H1N1) in April 2009 focused attention on influenza surveillance capabilities worldwide. In consultations before the 2009 outbreak of influenza subtype H1N1, the World Health Organization had concluded that the world was unprepared to respond to an influenza pandemic, due in part to inadequate global surveillance and response capacity. We describe a sentinel surveillance system that could enhance the quality of influenza epidemiologic and laboratory data and strengthen a country’s capacity for seasonal, novel, and pandemic influenza detection and prevention. Such a system would 1) provide data for a better understanding of the epidemiology and extent of seasonal influenza, 2) provide a platform for the study of other acute febrile respiratory illnesses, 3) provide virus isolates for the development of vaccines, 4) inform local pandemic planning and vaccine policy, 5) monitor influenza epidemics and pandemics, and 6) provide infrastructure for an early warning system for outbreaks of new virus subtypes.
Invasive Group B Streptococcal Disease in the Elderly, Minnesota, USA, 2003–2007
PDF Version [PDF - 399 KB - 3 pages]
N. J. Kothari et al.View Abstract
In Minnesota, incidence of invasive group B streptococcal disease was 3 times greater in older adults in long-term care facilities than in older adults in community settings (67.7/100,000 vs. 21.4/100,000) during 2003–2007. The overall case-fatality rate was 6.8%, and concurrent conditions were common among both groups.
Epidemiologic Study of Vibrio vulnificus Infections by Using Variable Number Tandem Repeats
PDF Version [PDF - 598 KB - 4 pages]
Y. Y. Broza et al.View Abstract
A 3-year environmental and clinical Vibrio vulnificus survey using simple-sequence repeats typing shows that V. vulnificus biotype 3 constitutes ≈21% of the bacterium population in tested aquaculture ponds as opposed to ≈86% of clinical cases. Simple-sequence repeats proved to be a useful epidemiologic tool, providing information on the environmental source of the pathogen.
Challenges of Investigating Community Outbreaks of Cyclosporiasis, British Columbia, Canada
PDF Version [PDF - 399 KB - 3 pages]
L. Shah et al.View Abstract
Investigations of community outbreaks of cyclosporiasis are challenged by case-patients’ poor recall of exposure resulting from lags in detection and the stealthy nature of food vehicles. We combined multiple techniques, including early consultation with food regulators, traceback of suspected items, and grocery store loyalty card records, to identify a single vehicle for a cyclosporiasis outbreak in British Columbia, Canada, in 2007.
Shiga Toxin–producing Escherichia coli, New Mexico, USA, 2004–2007
PDF Version [PDF - 357 KB - 3 pages]
S. Lathrop et al.View Abstract
Sporadic infection with Shiga toxin–producing Escherichia coli (STEC) in New Mexico increased from 0.9 cases per 100,000 population (95% confidence interval [CI] 0.5–1.36) in 2004 to 1.7 (95% CI 1.14–2.26) in 2007. Non-O157 STEC was more common in nonwhite residents, children <5 years of age, and urban residents.
Chronic Invasive Aspergillosis caused by Aspergillus viridinutans
PDF Version [PDF - 407 KB - 3 pages]
D. C. Vinh et al.View Abstract
Aspergillus viridinutans, a mold phenotypically resembling A. fumigatus, was identified by gene sequence analyses from 2 patients. Disease was distinct from typical aspergillosis, being chronic and spreading in a contiguous manner across anatomical planes. We emphasize the recognition of fumigati-mimetic molds as agents of chronic or refractory aspergillosis.
Legionella pneumophila in Rainwater on Roads
PDF Version [PDF - 467 KB - 3 pages]
R. Sakamoto et al.View Abstract
During rain, transient puddles form on roads, and this water is splashed into the air by moving vehicles. To determine whether this water contains Legionellapneumophila, we collected samples from roads. We found that L. pneumophila are abundant in these puddles, especially during warm weather.
West Nile Virus from Blood Donors, Vertebrates, and Mosquitoes, Puerto Rico, 2007
PDF Version [PDF - 418 KB - 3 pages]
E. A. Hunsperger et al.View Abstract
West Nile virus (WNV) was isolated from a human blood donor, a dead falcon, and mosquitoes in Puerto Rico in 2007. Phylogenetic analysis of the 4 isolates suggests a recent introduction of lineage I WNV that is closely related to WNV currently circulating in North America.
Lobomycosis in Man and Lobomycosis-like Disease in Bottlenose Dolphin, Venezuela
PDF Version [PDF - 499 KB - 3 pages]
L. Bermudez et al.View Abstract
We report 1 case of lobomycosis caused by Lacazia loboi in a fisherman and 1 case of lobomycosis-like disease in a bottlenose dolphin (Tursiops truncatus) along the coast of Venezuela. These findings suggest that the marine environment is a likely habitat for L. loboi and a reservoir for infection.
Predictors of Death after Severe Streptococcus pyogenes Infection
PDF Version [PDF - 441 KB - 4 pages]
T. L. Lamagni et al.View Abstract
An evaluation of the relative importance of host and pathogen factors on the survival rate of patients with invasive Streptococcus pyogenes infection found a number of clinical and demographic factors to be associated with risk for death. Some evidence suggested a seasonal pattern to patient survival rate.
Human Rabies and Rabies in Vampire and Nonvampire Bat Species, Southeastern Peru, 2007
PDF Version [PDF - 365 KB - 3 pages]
G. Salmón-Mulanovich et al.View Abstract
After a human rabies outbreak in southeastern Peru, we collected bats to estimate the prevalence of rabies in various species. Among 165 bats from 6 genera and 10 species, 10.3% were antibody positive; antibody prevalence was similar in vampire and nonvampire bats. Thus, nonvampire bats may also be a source for human rabies in Peru.
Avian Influenza Virus A (H5N1), Detected through Routine Surveillance, in Child, Bangladesh
PDF Version [PDF - 410 KB - 3 pages]
W. A. Brooks et al.View Abstract
We identified avian influenza virus A (H5N1) infection in a child in Bangladesh in 2008 by routine influenza surveillance. The virus was of the same clade and phylogenetic subgroup as that circulating among poultry during the period. This case illustrates the value of routine surveillance for detection of novel influenza virus.
Pigs as Source for Toxigenic Corynebacterium ulcerans
PDF Version [PDF - 349 KB - 2 pages]
R. Schuhegger et al.
Campylobacter jejuni HS:23 and Guillain-Barré Syndrome, Bangladesh
PDF Version [PDF - 380 KB - 3 pages]
Z. Islam et al.
Enzootic Sparganosis in Guangdong, People’s Republic of China
PDF Version [PDF - 342 KB - 2 pages]
M. Li et al.
Human Rhinovirus Group C in Hospitalized Children, Singapore
PDF Version [PDF - 416 KB - 3 pages]
B. Tan et al.
Nondominant Hemisphere Encephalitis in Patient with Signs of Viral Meningitis, New York, USA
PDF Version [PDF - 372 KB - 2 pages]
D. S. Asnis and N. Niazi
Tick-Borne Rickettsiosis in Traveler Returning from Honduras
PDF Version [PDF - 403 KB - 3 pages]
L. H. Chen and M. E. Wilson
KI and WU Polyomaviruses in Patients Infected with HIV-1, Italy
PDF Version [PDF - 401 KB - 3 pages]
M. Babakir-Mina et al.
Extreme Drug Resistance in Acinetobacter baumannii Infections in Intensive Care Units, South Korea
Y. K. Park et al.
More Diseases Tracked by Using Google Trends
PDF Version [PDF - 360 KB - 2 pages]
C. Pelat et al.
Human-to-Dog Transmission of Methicillin-Resistant Staphylococcus aureus
PDF Version [PDF - 426 KB - 3 pages]
B. E. Rutland et al.
Potential Malaria Reemergence, Northeastern Thailand
PDF Version [PDF - 342 KB - 2 pages]
T. Petney et al.
Fatal Borreliosis in Bat Caused by Relapsing Fever Spirochete, United Kingdom
PDF Version [PDF - 438 KB - 3 pages]
N. J. Evans et al.
Past, Present, and Future of Japanese Encephalitis
PDF Version [PDF - 326 KB - 8 pages]
S. L. Hills and D. C. Phillips
Books and Media
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For the world does not yet censure Those who tread the paths of dreams
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The conclusions, findings, and opinions expressed by authors contributing to this journal do not necessarily reflect the official position of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors' affiliated institutions. Use of trade names is for identification only and does not imply endorsement by any of the groups named above.
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