Incidence of West Nile virus infection in the Dallas-Fort Worth metropolitan area during the 2012 epidemic.

The 2012 West Nile virus (WNV) epidemic was the largest since 2003 and the North Texas region was the most heavily impacted. We conducted a serosurvey of blood donors from four counties in the Dallas-Fort Worth area to characterize the epidemic. Blood donor specimens collected in November 2012 were tested for WNV-specific antibodies. Donors positive for WNV-specific IgG, IgM, and neutralizing antibodies were considered to have been infected in 2012. This number was adjusted using a multi-step process that accounted for timing of IgM seroreversion determined from previous longitudinal studies of WNV-infected donors. Of 4971 donations screened, 139 (2·8%) were confirmed WNV IgG positive, and 69 (1·4%) had IgM indicating infection in 2012. After adjusting for timing of sampling and potential seroreversion, we estimated that 1·8% [95% confidence interval (CI) 1·5-2·2] of the adult population in the Dallas-Fort Worth area were infected during 2012. The resulting overall estimate for the ratio of infections to reported WNV neuroinvasive disease (WNND) cases was 238:1 (95% CI 192-290), with significantly increased risk of WNND in older age groups. These findings were very similar to previous estimates of infections per WNND case, indicating no change in virulence as WNV evolved into an endemic infection in the United States.

Enhanced Humoral Responses Induced by Targeting of Antigen to Murine Dendritic Cells.

Dendritic cells (DCs) are superior in their ability to induce and control adaptive immune responses. These qualities have motivated the hypothesis that targeted delivery of antigen to DCs in vivo may be an effective way of enhancing immunization. Recent results show that antigen targeted to certain DC surface molecules may indeed induce robust immune responses. Targeting of antigen to DCs can be accomplished by the means of monoclonal antibodies. This study compared the humoral responses induced in mice by in vivo targeting of DCs using monoclonal antibodies specific for CD11c, CD36, CD205, Clec6A, Clec7A, Clec9A, Siglec-H and PDC-TREM. The results demonstrate that antigen delivery to different targets on DCs in vivo gives rise to humoral responses that differ in strength. Targeting of antigen to CD11c, CD36, CD205, Clec6A, Clec7A and PDC-TREM induced significantly stronger antibody responses compared to non-targeted isotype-matched controls. Targeting of Clec9A and Siglec-H did not lead to efficient antibody responses, which may be due to unfavourable properties of the targeting antibody, in which case, other antibodies with the same specificity might elicit a different outcome. Anti-CD11c was additionally used for elucidating the impact of the route of vaccination, and the results showed only minor differences between the antibody responses induced after immunization either s.c., i.v. or i.p. Altogether, these data show that targeting of different surface molecules on DCs result in very different antibody responses and that, even in the absence of adjuvants, strong humoral responses was induced.

Estimated cumulative incidence of West Nile virus infection in US adults, 1999-2010.

West Nile virus (WNV) was first recognized in the USA in 1999. We estimated the cumulative incidence of WNV infection in the USA from 1999 to 2010 using recently derived age- and sex-stratified ratios of infections to WNV neuroinvasive disease (WNND) and the number of WNND cases reported to national surveillance. We estimate that over 3 million persons have been infected with WNV in the USA, with the highest incidence rates in the central plains states. These 3 million infections would have resulted in about 780 000 illnesses. A substantial number of WNV infections and illnesses have occurred during the virus' first decade in the USA.

Transfusion-transmitted arboviruses.

There exists considerable risk for transfusion transmission of arboviruses due to short periods of asymptomatic viraemia in populations with variable and sometimes extremely high incidence of arboviral infections. Aside from West Nile virus, few arbovirus transfusion transmissions have been proven, mostly due to difficulties in ruling out vector-borne transmission in recipients with arbovirus disease. Nevertheless, arbovirus transfusion risk models and assessments of viraemia prevalence in blood donations indicate substantial transfusion transmission of dengue and Chikungunya viruses in epidemic areas. Many other arboviruses, several of which are importation risks in the Americas, Europe and Asia, also cause large outbreaks and threaten transfusion safety. Prevention largely depends on excluding donors from outbreak areas or implementation of highly sensitive nucleic acid amplification tests. Because of the increasing emergence of arboviral disease globally, it is prudent to prepare for both endemic and exotic arboviruses capable of producing large epidemics and subsequent transfusion transmission risk.

West Nile virus infection and serologic response among persons previously vaccinated against yellow fever and Japanese encephalitis viruses.

It is hypothesized that previous heterologous flaviviral exposure may modulate clinical illness among persons infected with West Nile virus (WNV). Little is known about the serological response in such persons. In summer 2003, a WNV outbreak occurred in Colorado, the location of the Centers for Disease Control and Prevention, Division of Vector-Borne Infectious Diseases (DVBID). DVBID employees, most previously vaccinated with yellow fever virus (YFV) or Japanese encephalitis virus (JEV) vaccines, were studied to determine whether previous vaccination affected symptom development among those subsequently infected with WNV during the outbreak, as well as their serological response. Serum samples collected in December 2003 and previously banked samples were tested using the plaque reduction neutralization test (PRNT) against WNV, Saint Louis encephalitis virus, dengue- 4 virus, JEV, and YFV. Specimens shown to have WNV antibody by PRNT were tested by IgM and IgG enzymelinked immunosorbent assays (ELISAs). Ten (9%) of 113 serosurvey participants had WNV neutralizing antibody titers in December 2003. PRNT titers from previous specimens showed that one of the ten had seroconverted to WNV before 2003. Of the remaining nine participants, seven reported illness in the summer of 2003, two of which were unvaccinated and five previously vaccinated. In the December 2003 specimens, five persons previously unvaccinated or vaccinated only against YFV had a fourfold or greater neutralizing titer with WNV than with other flaviviruses, whereas no persons previously vaccinated against JEV or JEV and YFV showed a similar difference in neutralizing titers. Eight of nine persons infected in 2003 had negative or indeterminate WNV MAC-ELISA results in the December 2003 sample; the ninth person was vaccinated against YFV one month previously, and was also YFV positive by MAC-ELISA. We conclude that previous flaviviral vaccination does not markedly affect the development of WNV fever and that the IgM antibody response in patients without neuroinvasive WNV disease is transient.

Providing HIV counseling and testing services in methadone maintenance programs.

Counseling about AIDS and optional confidential testing for antibody to HIV-1 have been available in state-supported methadone maintenance programs in Connecticut since 1 January 1987. In the first 2 years of the program, 2118 people received pre-test counseling. Overall, 1521 people agreed to anti-HIV-1-antibody testing and 1010 received post-test counseling. Other than the pre- and post-test counseling sessions, a total of 1600 HIV counseling sessions were conducted. This is the first statewide program for providing HIV counseling and testing in methadone maintenance programs in the United States. Our experience suggests that the prevention of both drug use and HIV-1 transmission can be integrated in drug treatment centers.

No evidence for female-to-female HIV transmission among 960,000 female blood donors. The HIV Blood Donor Study Group.

The frequency of female-to-female HIV transmission was assessed among 960,000 female blood donors at 20 large U.S. blood centers during 1990. Of 144 HIV-seropositive women identified, 106 were interviewed. None of the interviewed women reported sex exclusively with women since 1978. Three seropositive women reported sex contact with women as well as with either bisexual men or men who had used i.v. drugs. In this large population, we identified no woman who was infected with HIV from sexual contact with another woman.

Prevalence of antibody to the human immunodeficiency virus among clinical laboratory specimens: findings from a survey of primary care physicians.

To evaluate human immunodeficiency virus type 1 (HIV-1) infection among patients of primary care physicians, we performed anonymous, unlinked HIV-1 antibody testing on leftover blood specimens submitted to 10 large commercial clinical laboratories for complete blood cell count or hematocrit determination, the most commonly ordered diagnostic tests. From January through August 1990, 55,613 specimens submitted by general internists, pediatricians, and family practitioners were sampled; 1,104 (2.0%) had HIV-1 antibody. Seroprevalence among the laboratories varied 50-fold, from 0.3 to 12.4%. The HIV-1 prevalence at each laboratory was not always consistent with the AIDS incidence in the area served by the laboratory. Overall the seroprevalence was almost eight times higher in men (3.9%) than in women (0.5%). Specimens from seropositive persons, especially from men, were unevenly distributed among the physician practices; only three practices submitted approximately 50% of all specimens from seropositive men. These data indicate that a few physicians treat the majority of HIV-1-infected primary care patients. The HIV-1 prevalence among specimens at a clinical laboratory is thus determined by whether few physicians submit specimens to that laboratory. These results could be of use, for instance, in analyzing proposals to mandate physician reporting of HIV-1 infection. The high HIV-1 prevalence among laboratory specimens underscores the potential for exposure to HIV-1-infected blood by clinical laboratory personnel and emphasizes the need for universal precautions for all blood specimens.

Unusual manifestations of secondary syphilis occurring after orthotopic liver transplantation.

A 48-year-old actively homosexual man who had undergone liver transplantation for cirrhosis secondary to hepatitis B infection six years previously presented with a syndrome of diffuse pain, cholestasis, and low-grade fever. The development of thrombocytopenia and persistent hypoprothrombinemia precluded liver biopsy. Subsequently, a skin eruption and VDRL result of 1:128 indicated that most of the findings could be explained by a diagnosis of secondary syphilis with luetic hepatitis and periostitis. This impression was confirmed by a complete response to penicillin therapy. The relation of thrombocytopenia to lues in this case remains uncertain.

Acquired immunodeficiency syndrome and secondary school students: their knowledge is limited and they want to learn more.

Information was gathered from 657 junior high school and senior high school students in two Connecticut school districts regarding their knowledge of acquired immunodeficiency syndrome (AIDS). Although many students had some factual knowledge about the virus that causes AIDS, many students were misinformed about methods of viral transmission, high-risk groups for acquiring AIDS, and methods to avoid acquisition of the virus. Most students did not recognize the existence of a carrier state. Responses from students of different grades, ages, sexes, races, and school districts differed rarely and without apparent pattern. Students reported that they had learned about AIDS mostly from television or radio (57%) or magazines or newspapers (16%); few had learned from persons with whom they had frequent contact, such as parents (6%) or teachers (4%). Seventy-four percent of students said they wanted to learn more about AIDS, and 49% said they wanted to learn it in school. Results of this study indicated that students' knowledge about AIDS is not adequate, students wish to learn more, and information about AIDS should be presented in public schools.

An outbreak of pyodermas among neonates caused by ultrasound gel contaminated with methicillin-susceptible Staphylococcus aureus.

OBJECTIVE: To investigate an outbreak of methicillin-susceptible Staphylococcus aureus (MSSA) infections in a neonatal clinic. DESIGN: Prospective chart review, environmental sampling, and genotyping by two independent methods: pulsed-field gel electrophoresis (PFGE) and randomly amplified polymorphic DNA polymerase chain reaction (RAPD-PCR). A case-control study was performed with 31 controls from the same clinic. SETTING: A German 1,350-bed tertiary-care teaching university hospital. RESULTS: There was a significant increase in the incidence of pyodermas with MSSA; 10 neonates in good physical condition with no infection immediately after birth developed pyodermas. A shared spatula and ultrasound gel were the only identified infection sources. The gel contained MSSA and was used for hip joint sonographies in all neonates. PFGE and RAPD-PCR patterns from 6 neonates and from the gel were indistinguishable and thus genetically related clones. The case-control study revealed no significant risk factor with the exception of cesarean section (P=.006). The attack rate by days of hip-joint sonography between April 15 and April 27, 1994, was 11.8% to 40%. CONCLUSIONS: Inappropriate hygienic measures in connection with lubricants during routine ultrasound scanning may lead to nosocomial S. aureus infections of the skin. To our knowledge this source of S. aureus infections has not previously been described.

A characteristic effect of hallucinogens on investigatory responding in rats.

The disruption of the temporal distribution of investigatory responses by rats in a novel hole-board following lysergic acid diethylamide-25 (LSD), as described in a companion paper (Geyer and Light, 1979), was found to be a characteristic effect of a variety of hallucinogens. Similar effects were produced by indoleamine hallucinogens, such as LSD, N,N-dimethyltryptamine, and psilocin, and by phenylethylamine hallucinogens, such as mescaline or 2,5-dimethoxy-4-methylamphetamine (DOM). Congeners of DOM that are inactive in humans had no significant effects. Furthermore, of a variety of other psychoactive drugs tested, only apomorphine produced an effect similar to that of the hallucinogens. These results suggest that a simple behavioral measure of exploration in a hole-board may provide a useful animal model with which to examine the common effects of hallucinogens.

West Nile virus serosurvey and assessment of personal prevention efforts in an area with intense epizootic activity: Connecticut, 2000.

West Nile virus (WNV) can cause large outbreaks of febrile illness and severe neurologic disease. This study estimates the seroprevalence of WNV infection and assesses risk perception and practices regarding potential exposures to mosquitoes of persons in an area with intense epizootics in 1999 and 2000. A serosurvey of persons aged > or = 12 years was conducted in southwestern Connecticut during October 10-15, 2000, using household-based stratified cluster sampling. Participants completed a questionnaire regarding concern for and personal measures taken with respect to WNV and provided a blood sample for WNV testing. Seven hundred thirty persons from 645 households participated. No person tested positive for WNV (95% CI: 0-0.5%). Overall, 44% of persons used mosquito repellent, 56% practiced > or = two personal precautions to avoid mosquitoes, and 61% of households did > or = two mosquito-source reduction activities. In multivariate analyses, using mosquito repellent was associated with age < 50 years, using English as the primary language in the home, being worried about WNV, being a little worried about pesticides, and finding mosquitoes frequently in the home (P<0.05). Females (OR = 2.0; CI = 1.2-2.9) and persons very worried about WNV (OR = 3.8; CI = 2.2-6.5) were more likely to practice > or = two personal precautions. Taking > or = two mosquito source reductions was associated with persons with English as the primary language (OR = 2.0; CI = 1.1-3.5) and finding a dead bird on the property (OR = 1.8; CI = 1.1-2.8). An intense epizootic can occur in an area without having a high risk for infection to humans. A better understanding of why certain people do not take personal protective measures, especially among those aged > or = 50 years and those whose primary language is not English, might be needed if educational campaigns are to prevent future WNV outbreaks.

Platelet aggregation and fatty acid composition of platelets in type 1 diabetes mellitus.

A raised content of arachidonic acid in platelets from diabetic patients with retinopathy was found without differences in platelet aggregation: platelet aggregability was not related to platelet fatty acid composition. In diabetes, platelet aggregation was inversely correlated to non-esterified fatty acids in plasma and may suggest an inhibiting effect. Mean platelet volume was raised in the diabetic patients, but without hyperaggregability. The findings do not exclude a relationship between platelet fatty acids and platelet aggregability, but suggest that variations in levels of non-esterified fatty acids in plasma might interfere with platelet aggregation.

Mescaline increases startle responding equally in normal and raphe-lesioned rats.

To test the possible involvement of serotonin-containing cells of the midbrain in mediating the effects of mescaline on startle responding, electrolytic lesions were made in either the dorsal or median raphe nucleus in rats. Decreases in either striatal or hippocampal tryptophan hydroxylase activity confirmed the effectiveness of the lesions. One week later, startle was measured in response to 30 air-puff stimuli for each rat. Median, but not dorsal, raphe lesions increased startle magnitudes throughout the test session. The following day each group was divided into matched halves and were given 60 trials, 30 minutes after intraperitoneal injection of either saline or 10 mg/kg mescaline. Despite the large differences in baseline startle among the groups, mescaline produced comparable 25% increases in startle magnitudes in both sham- and raphe-lesioned animals. This result fails to support the hypothesis that increased startle responding produced by mescaline is mediated by the midbrain raphe nuclei.

Methodologic approaches to surveillance of HIV infection among blood donors.

Blood donors make up the largest group in the United States that is tested for human immunodeficiency virus, type 1 (HIV) antibody. The blood donor population is ideal for detecting and quantifying uncommon or unrecognized modes of HIV transmission in the general population because persons at known risk for HIV infection are excluded from donating blood. The national HIV surveillance program consists of a centralized computer database of information on all donations at selected American Red Cross blood centers, which together account for about a quarter of the blood supply, and all donations at 20 regional blood centers where seropositive blood donors are interviewed to evaluate their risk factors for HIV infection and to determine their epidemiologic characteristics and motives for donation. Trends in HIV prevalence and incidence within specific demographic subgroups are determined for first-time and repeat donors. Combining the trends with HIV-risk profile data from seropositive donors provides a rate for HIV seropositive donors with no identified risk. Epidemiologic and behavioral data from seropositive donors will help in the development and evaluation of future donor deferral strategies.

Methods of surveillance for HIV infection in primary care outpatients in the United States.

Primary care outpatients provide a good sentinel population for monitoring levels and trends of HIV infection in the United States. Because a broad cross section of the population seeks primary medical care, excess blood from specimens routinely collected for other purposes is available for anonymous, unlinked HIV testing, and all age groups and both sexes can be sampled. The CDC family of surveys includes two surveys of primary care outpatients: (a) a survey of 100,000 blood specimens per year submitted by more than 6,000 primary care physicians to a national diagnostic laboratory for complete blood count or hematocrit and (b) a survey of approximately 10,000 blood specimens per year from a network of 242 primary care physicians. Each survey has different advantages: the laboratory-based survey has a large sample from a large population base, and the physician network survey has a well-defined patient population in which each patient's clinical condition can be determined. In the primary care physician network, a concurrent study of clinical patterns of disease in patients with recognized HIV infection provides additional information on the clinical syndromes associated with HIV infection and estimates of the occurrence of unrecognized HIV infection.

Employee smoking behavior changes and attitudes following a restrictive policy on worksite smoking in a large company.

A Connecticut insurance company adopted a policy prohibiting smoking in all work areas. Three months later, the authors assessed smoking behavior changes and attitudes of a sample of 1,210 employees, 56.6 percent of the total. The survey showed that the policy of no smoking in the work areas did not markedly affect smoking cessation, that it reduced cigarette consumption for those who continued to smoke, that those who previously smoked most were most likely to reduce consumption, and that despite negative feelings about the policy by smokers, only 29 percent of smokers and 4 percent of nonsmokers wanted a worksite smoking policy eliminated. During the 1-year prepolicy period, smoking prevalence decreased from 25.2 percent to 23.6 percent of the sample. During the 3-month postpolicy period, smoking prevalence decreased to 22.0 percent. During the prepolicy period, consumption did not change significantly (from 0.99 to 0.95 packs per day) and few smokers increased (11 percent) or decreased (13 percent) consumption. During the postpolicy period, consumption decreased by 32 percent to 0.67 packs per day, and 12 times as many smokers decreased (44 percent) as increased (3.5 percent) consumption. Of those who smoked at least two packs per day, 93 percent smoked less after the policy. Among nonsmokers, 70 percent thought the policy had a positive overall effect on the work environment, compared with 19 percent of smokers.

The family of HIV seroprevalence surveys: objectives, methods, and uses of sentinel surveillance for HIV in the United States.

During 1987-89, the Centers for Disease Control (CDC), in collaboration with State and local health departments, other Federal agencies, blood collection agencies, and medical research institutions, implemented a national sentinel surveillance system for human immunodeficiency virus (HIV) infection. This ongoing surveillance system, known as the CDC family of HIV seroprevalence surveys, uses standardized survey and HIV serologic testing procedures in a group of sentinel populations from geographically diverse metropolitan areas, States, and Territories of the United States. As of September 1989, sentinel surveillance for HIV infection was being conducted in 41 States, Puerto Rico, and 39 metropolitan areas, including the District of Columbia. Information from this system complements AIDS surveillance data to assist health officials to direct resources and develop strategies for HIV prevention and health-care programs.

Guidelines for designing rapid assessment surveys of HIV seroprevalence among hospitalized patients. Centers for Disease Control and Prevention.

The Centers for Disease Control and Prevention has developed guidelines for determining HIV seroprevalence among patients seeking medical care at acute-care hospitals. The guidelines enable hospital staff members to perform a simple, rapid, and inexpensive survey to determine seroprevalence among the patient population, protecting the anonymity of those who are tested. The guidelines are based on national experience with large-scale anonymous, unlinked HIV serosurveys. The data from a rapid assessment survey are particularly useful for evaluating the need to provide routine, voluntary HIV counseling and testing and treatment for HIV infection. Beyond that, such data can be used in targeting education efforts, in reinforcing the use of appropriate universal precautions, in resource allocation, and in determining the need for further studies of HIV infection among the population in the hospital catchment area.