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Zhong D.,University of California at Irvine | Lo E.,University of California at Irvine | Cummings R.,Orange County Vector Control District | Bonizzoni M.,University of California at Irvine | And 8 more authors.
PLoS ONE | Year: 2013

The Asian tiger mosquito, Aedes albopictus, is an anthropophilic aggressive daytime-biting nuisance and an efficient vector of certain arboviruses and filarial nematodes. Over the last 30 years, this species has spread rapidly through human travel and commerce from its native tropical forests of Asia to every continent except Antarctica. In 2011, a population of Asian tiger mosquito (Aedes albopictus) was discovered in Los Angeles (LA) County, California. To determine the probable origin of this invasive species, the genetic structure of the population was compared against 11 populations from the United States and abroad, as well as preserved specimens from a 2001 introduction into California using the mitochondrial cytochrome c oxidase 1 (CO1) gene. A total of 66 haplotypes were detected among samples and were divided into three main groups. Aedes albopictus collected in 2001 and 2011 from LA County were genetically related and similar to those from Asia but distinct from those collected in the eastern and southeastern United States. In view of the high genetic similarities between the 2001 and 2011 LA samples, it is possible that the 2011 population represents in part the descendants of the 2001 introduction. There remains an imperative need for improved surveillance and control strategies for this species.


Hills S.L.,Centers for Disease Control and Prevention | Stoltey J.,University of California at San Francisco | Martinez D.,Harris County Public Health and Environmental Services | Kim P.Y.,U.S. Air force | And 3 more authors.
Journal of Travel Medicine | Year: 2014

Background Japanese encephalitis (JE) virus is the leading cause of vaccine-preventable encephalitis in Asia. Although the risk for acquiring JE for most travelers to Asia is low, it varies based on the destination, season, trip duration, and activities. Methods We present case reports of three US adults who were infected with JE virus while traveling or residing in Asia. Results Among the three JE patients, the first made a 10-day trip to mainland China and participated in outdoor activities in a rural area, the second had been resident in Taiwan for 4 months, and the third, fatal case was an expatriate living in South Korea. Conclusions JE should be considered in the differential diagnosis for any patient with an acute neurologic infection, who has recently been in a JE-endemic country. Health-care providers should assess the itineraries of travelers to JE-endemic countries, provide guidance on personal protective measures to prevent vector-borne diseases, and consider recommending JE vaccine for travelers at increased risk for JE virus infection. © 2014 International Society of Travel Medicine.


Murray K.O.,Baylor College of Medicine | Garcia M.N.,Baylor College of Medicine | Rahbar M.H.,University of Texas Health Science Center at Houston | Martinez D.,Harris County Public Health and Environmental Services | Rossmann S.,Gulf Coast Regional Blood Center
PLoS ONE | Year: 2014

In 2012, we witnessed a resurgence of West Nile virus (WNV) in the United States, with the largest outbreak of human cases reported since 2003. WNV is now endemic and will continue to produce epidemics over time, therefore defining the long-term consequences of WNV infection is critical. Over a period of eight years, we prospectively followed a cohort of 157 WNV-infected subjects in the Houston metropolitan area to observe recovery over time and define the long-term clinical outcomes. We used survival analysis techniques to determine percentage of recovery over time and the effects of demographic and co-morbid conditions on recovery. We found that 40% of study participants continued to experience symptoms related to their WNV infection up to 8 years later. Having a clinical presentation of encephalitis and being over age 50 were significantly associated with prolonged or poor recovery over time. Since the health and economic impact as a result of prolonged recovery, continued morbidity, and related disability is likely substantial in those infected with WNV, future research should be aimed at developing effective vaccines to prevent illness and novel therapeutics to minimize morbidity, mortality, and long-term complications from infection. © 2014 Murray et al.


Murray K.O.,Baylor College of Medicine | Rodriguez L.F.,University of Texas Health Science Center at Houston | Herrington E.,University of Texas Health Science Center at Houston | Kharat V.,University of Texas Health Science Center at Houston | And 7 more authors.
Vector-Borne and Zoonotic Diseases | Year: 2013

Houston, Texas, maintains an environment conducive to dengue virus (DENV) emergence; however, surveillance is passive and diagnostic testing is not readily available. To determine if DENV is present in the area, we tested 3768 clinical specimens (2138 cerebrospinal fluid [CSF] and 1630 serum) collected from patients with suspected mosquito-borne viral disease between 2003 and 2005. We identified 47 immunoglobulin M (IgM)-positive dengue cases, including two cases that were positive for viral RNA in serum for dengue serotype 2. The majority of cases did not report any history of travel outside the Houston area prior to symptom onset. The epidemic curve suggests an outbreak occurred in 2003 with continued low-level transmission in 2004 and 2005. Chart abstractions were completed for 42 of the 47 cases; 57% were diagnosed with meningitis and/or encephalitis, and 43% met the case definition for dengue fever. Two of the 47 cases were fatal, including one with illness compatible with dengue shock syndrome. Our results support local transmission of DENV during the study period. These findings heighten the need for dengue surveillance in the southern United States. © 2013 Mary Ann Liebert, Inc.


PubMed | Centers for Disease Control and Prevention, Harris County Public Health and Environmental Services and Fort Bend County Health and Human Services
Type: Journal Article | Journal: American journal of infection control | Year: 2014

We investigated a multifacility outbreak of acute hepatitis B virus infection involving 21 residents across 10 assisted living facilities in Texas during the period January 2008 through July 2010. Epidemiologic and laboratory data suggested that these infections belonged to a single outbreak. The only common exposure was receipt of assisted monitoring of blood glucose from the same home health care agency. Improved infection control oversight and training of assisted living facility and home health care agency personnel providing assisted monitoring of blood glucose is needed.


News Article | January 15, 2016
Site: news.yahoo.com

The proboscis of an Asian tiger mosquito (Aedes albopictus), a virus vector common in North America, as it feeds on human blood. More The rapid spread of a disease called Zika virus urgently requires attention, two leading researchers say. Zika virus is the most recent in a list of viruses that were formerly confined to remote niches of the world but are now expanding their reach into the Northern Hemisphere. Much about these viruses is still poorly understood, wrote Dr. Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases (NIAID), and Dr. David Morens, senior scientific advisor for the NIAID, in an article published in the New England Journal of Medicine on Thursday (Jan. 14). Zika virus is carried by mosquitos and causes generally mild symptoms like fever and rashes. However, it has recently been linked to an alarming rise in newborns with microcephaly — a condition causing reduced brain development and abnormally small heads — in Brazil. Ten times as many cases were reported there in 2015 than in previous years, according to the Centers for Disease Control and Prevention (CDC). In their new article, Fauci and Morens evaluated the extent of the threat posed by this fast-spreading virus. Health officials have been aware of Zika virus for 60 years, but it is only within the past year that data gathered from infected populations hinted at the more severe consequence of infection, the researchers said. [Tiny & Nasty: Images of Things That Make Us Sick] In French Polynesia, an epidemic of diverse neurologic conditions happened concurrently with Zika virus outbreaks, suggesting an association between the two. And some public health officials have attributed the recent and alarming spike in infants with microcephaly in Brazil to Zika infections contracted by women while they were pregnant. However, Fauci and Morens warn, it's too soon to conclude that Zika virus is definitely responsible for these conditions. Commercial tests for Zika are yet to be developed, and it is possible that a closely related disease, like dengue virus, actually caused some suspected Zika infections, the researchers said. "Intensive investigative research" is required to look at the possible link between the virus and the birth defects, Fauci and Morens said. But even if no link is discovered, researchers must learn more about Zika, they said. On Dec. 31, the CDC reported the first locally acquired Zika virus case in Puerto Rico, farther north in the Americas than ever seen before. And on Monday (Jan. 11), a traveler who had recently returned to the United States from Latin America was diagnosed with Zika in Houston, according to the Texas' Harris County Public Health and Environmental Services (HCPHES). Harris County officials stated that the infected person had symptoms "that are often associated with the Zika virus, which include fever, rash and joint pain." This case isn't a cause for alarm — Zika can't spread directly between people, and as of Jan. 14 there have been no reports of anyone acquiring the illness while in the United States, according to the CDC. However, one species of the mosquito group known to carry Zika, the Aedes genus, is common across North America. This bug, called the Asian tiger mosquito, carries viruses related to Zika, such as chikungunya and dengue, and is especially common in U.S. states that border the Gulf of Mexico, as shown by a species distribution map created by the CDC. As yet, there is no vaccine against Zika and no cure for the infection. But Fauci and Morens wrote that they are skeptical about the benefit of pursuing a vaccine to halt Zika's spread, suggesting that vaccines are an inefficient solution to epidemics that appear seemingly out of nowhere. Vaccinating entire populations could be prohibitively expensive, the authors added. The more promising course, they wrote, would include implementing public health strategies that respond more quickly to contain infections before they reach epidemic proportions, and developing broad-spectrum antivirals, rather than following the more traditional treatment approach of "one bug, one drug." Perhaps the most unusual thing about Zika is that "it's not so unusual anymore," said Dr. Bruce Hirsch, an infectious disease specialist with Northwell Health in New York, who was not involved in writing the new editorial. "These exotic infections like Zika, dengue, West Nile and chikungunya are becoming very well-known and familiar," he told Live Science.


Mann B.R.,University of Texas Medical Branch | McMullen A.R.,University of Texas Medical Branch | Swetnam D.M.,University of Texas Medical Branch | Salvato V.,Harris County Public Health and Environmental Services | And 6 more authors.
Emerging Infectious Diseases | Year: 2013

We investigated the genetics and evolution of West Nile virus (WNV) since initial detection in the United States in 1999 on the basis of continual surveillance studies in the Houston, Texas, USA, metropolitan area (Harris County) as a surrogate model for WNV evolution on a national scale. Full-length genomic sequencing of 14 novel 2010-2012 WNV isolates collected from resident birds in Harris County demonstrates emergence of 4 independent genetic groups distinct from historical strains circulating in the greater Houston region since 2002. Phylogenetic and geospatial analyses of the 2012 WNV isolates indicate closer genetic relationship with 2003-2006 Harris County isolates than more recent 2007-2011 isolates. Inferred monophyletic relationships of these groups with several 2006-2009 northeastern US isolates supports potential introduction of a novel WNV strain in Texas since 2010. These results emphasize the need to maintain WNV surveillance activities to better understand WNV transmission dynamics in the United States.


McMullen A.R.,University of Texas Medical Branch | May F.J.,University of Texas Medical Branch | Li L.,University of Texas Medical Branch | Guzman H.,University of Texas Medical Branch | And 4 more authors.
Emerging Infectious Diseases | Year: 2011

Previous studies of North American isolates of West Nile virus (WNV) during 1999-2005 suggested that the virus had reached genetic homeostasis in North America. However, genomic sequencing of WNV isolates from Harris County, Texas, during 2002-2009 suggests that this is not the case. Three new genetic groups have been identifi ed in Texas since 2005. Spread of the southwestern US genotype (SW/WN03) from the Arizona/Colorado/northern Mexico region to California, Illinois, New Mexico, New York, North Dakota, and the Texas Gulf Coast demonstrates continued evolution of WNV. Thus, WNV continues to evolve in North America, as demonstrated by selection of this new genotype. Continued surveillance of the virus is essential as it continues to evolve in the New World.


Davila J.A.,Michael bakey Veterans Affairs Medical Center | Davila J.A.,Baylor College of Medicine | Miertschin N.,Thomas Street Health Center | Sansgiry S.,Michael bakey Veterans Affairs Medical Center | And 5 more authors.
AIDS Care - Psychological and Socio-Medical Aspects of AIDS/HIV | Year: 2013

African-American and Hispanic HIV-infected youth are a high risk group for not remaining in HIV care. We examined differences in retention in care among 174 HIV-infected African-American and Hispanic youth between 13 and 23 years old who presented for HIV primary care between 1 January 2002 and 31 August 2008. Patients were included in three service eras, based on when they entered the clinic: when no youth-specific services were available (the decentralized era), after formation of a youth clinic staffed by adolescent providers and a case-manager (the centralized era), and after educational activities and support groups were added and the social services staff were trained in the use of motivational interviewing (the centralized with supportive services era). Patient and attendance data for the 12-months following entry into care were captured. Retention in HIV care was examined using two different measures: adequate visit constancy (at least three quarters with at least one visit in each quarter) and having a gap in care (two consecutive medical visits ≥180 days apart). Adequate visit constancy improved by service era from 31% in the decentralized era to 57% in the centralized era and 65% in the centralized with supportive services era (p=0.01). The percent of patients with no gap in care remained stable at about 80% in the decentralized and centralized eras, but then increased to 96% in the centralized with supportive services era (p=0.04). Results suggest that centralizing youth-specific care and expanding youth services can improve retention in HIV care. These system changes should be considered when resources allow. © 2013 Copyright Taylor and Francis Group, LLC.


Fredregill C.L.,Harris County Public Health and Environmental Services | Motl G.C.,Harris County Public Health and Environmental Services | Dennett J.A.,Harris County Public Health and Environmental Services | Flatt K.L.,Harris County Public Health and Environmental Services | Bueno Jr. R.,Harris County Public Health and Environmental Services
Journal of the American Mosquito Control Association | Year: 2011

In 2008 and 2009, our current thermal fogging methods and materials were evaluated in underground systems against feral and laboratory strains of adult Culex quinquefasciatus. Culex quinquefasciatus adults collected from storm drain systems the night before treatment were tested concurrently with adults from a susceptible laboratory strain (Sebring) in 10 separate tests. During 2008, there were no significant differences in the low mean percent control obtained between any of the feral populations (29.39%) and susceptible (Sebring) populations (56.04%) tested, whereas in 2009, application of mineral oil alone yielded extremely low, but significantly different mean percent control at 0.99% for ferals and 0.01% for Sebrings. During 2009 mineral oil evaluations, 45,677 droplets were collected in storm drains at distances of 99.1, 50.6, 57.9, 67.7, and 109.7 m from the application site, with 99% of the droplets below 3 μ in diam; additionally, we found no significant differences between mean percent control of Sebring and feral mosquito populations using the higher (3.2×- ) 1-10 application rate of Pyrocide®. However, mean percent control between the feral and susceptible strain (Sebring) during 2009 was lower than in 2008 at 16.55% for ferals and 24.43% in Sebrings. Results indicated that control methodologies and/or chemicals used were ineffective at controlling Cx. quinquefasciatus in storm drains using the chosen experimental design. Based upon this information, thermal fog operations were discontinued due to lack of effectiveness. © 2011 by The American Mosquito Control Association, Inc.

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