Molecular epidemiology of an outbreak of human parainfluenza virus 3 among oncology patients.

A hospital outbreak of human parainfluenza virus type 3 (HPIV-3) in haematologic oncology patients is described in 12 patients over a four-week period. Exposure histories and molecular analysis of HPIV-3 isolates suggest that both community-acquired and nosocomially transmitted infections occurred during this outbreak. Molecular analysis of HPIV-3 isolates indicated that a chain of transmission occurred among multiple patients in an oncology ward. This transmission was later determined to be associated with the movement of fomites, visitors, and activities in the unit. The infection prevention team stopped nosocomial spread of HPIV-3 through interventions including advanced cleaning procedures.

Epidemiological study of people living in rural North Carolina for novel respiratory viruses.

During the last 10 years, scientists have grown increasingly aware that emerging respiratory viruses are often zoonotic in their origin. These infections can originate from or be amplified in livestock. Less commonly recognized are instances when humans have transmitted their respiratory pathogens to animals (reverse zoonoses). Even with this knowledge of viral exchange at the human-livestock interface, few studies have been conducted to understand this cross-over. In this pilot study, we examined persons with influenza-like illness at an outpatient clinic for evidence of infection with novel zoonotic respiratory pathogens in rural North Carolina where there are dense swine and poultry farming. Environmental air sampling was also conducted. From July 2016 to March 2017, a total of 14 human subjects were enrolled and sampled, and 192 bioaerosol samples were collected. Of the 14 human subject samples molecularly tested, three (21.4%) were positive for influenza A, one (7.1%) for influenza B and one (7.1%) for human enterovirus. Of the 192 bioaerosol samples collected and tested by real-time RT-PCR or PCR, three (1.6%) were positive for influenza A and two (1.0%) for adenovirus. No evidence was found for novel zoonotic respiratory viruses.

Epizootics in Industrial Livestock Production: Preventable Gaps in Biosecurity and Biocontainment.

While technological advances in animal husbandry have facilitated increases in global meat production, the high density and geographic concentration of food animal production facilities pose risks of infectious disease transmission. The scale of the 2014-2015 highly pathogenic avian influenza H5N2 outbreak in the United States demonstrates the challenges in achieving pathogen control within and around industrial animal facilities using existing technologies. We discuss gaps in current practice in two specific systems within these facilities - ventilation and waste management - which are under-recognized as important drivers of microbial porosity. The development of innovative ventilation systems to reduce influx and efflux of pathogens is critically needed, and cross-sectoral partnerships should be incentivized to do so. Adapting current human biosolid treatment technologies for farm applications, reducing animal stocking density and shifting waste management responsibility from farmer to corporation would reduce risk from current manure management systems. While innovative approaches to functionally altering the industrial food animal production system remain important priorities to promote sustainability, our intention here is to identify gaps within the current system that allow for pathogen emergence and transmission and address specific areas in which technological, administrative or policy changes are necessary to mitigate these risks.

Evidence for unapparent Brucella canis infections among adults with occupational exposure to dogs.

Human serological assays designed to detect brucellosis will miss infections caused by Brucella canis, and low levels of periodic bacteremia limit diagnosis by blood culture. Recent B. canis outbreaks in dogs and concomitant illnesses in caretakers suggest that unapparent human infections may be occurring. With more than a quarter of a million persons in occupations involving dogs, and nearly 80 million dog owners in the United States, this pathogen is an under-recognized human health threat. To investigate occupational exposure to B. canis, we adapted a commercial canine serological assay and present the first controlled seroepidemiological study of human B. canis infections in recent years. 306 adults with occupational exposure to dogs and 101 non-matched, non-canine-exposed subjects were enrolled. Antibodies were detected using the canine D-Tec(®) CB rapid slide agglutination test (RSAT) kit with a secondary 2-mercaptoethanol (ME)-RSAT. Results were validated on a blinded subset of sera with an additional RSAT and indirect enzyme-linked immunoassay at the National Administration of Laboratories and Health Institutes (ANLIS) in Argentina. Seroprevalence ranged from 10.8% (RSAT) to 3.6% (ME-RSAT) among canine-exposed subjects. Kennel employees were more likely to test RSAT seropositive compared with other canine exposures (OR = 2.7; 95% CI, 1.3-5.8); however, low seroprevalence limited meaningful occupational risk factor analyses. Two seropositive participants reported experiencing symptoms consistent with brucellosis and having exposure to B. canis-infected dogs; however, temporality of symptom onset with reported exposure could not be determined. D-Tec(®) CB results had substantial agreement with ANLIS assays (Cohen's kappa = 0.60-0.68). These data add to a growing body of literature suggesting that people occupationally exposed to dogs may be at risk of unapparent B. canis infection. It seems prudent to consider B. canis as an occupational public health concern and encourage the development of serological assays to detect human B. canis infections.

Antibodies to Trichomonas vaginalis surface glycolipid.

BACKGROUND: Human trichomoniasis is the most common non-viral sexually transmitted disease, yet immune responses are not well studied. METHODS: Since the Trichomonas vaginalis lipophosphoglycan (TvLPG) is an important virulence factor, a bank of eight monoclonal antibodies was generated to define the antigen in clinical isolates. The TvLPG-specific antibody response of women who were culture positive (n=33) or negative (n=33) for T vaginalis infection was determined by isotype-specific ELISA. RESULTS: The bank of monoclonal antibodies reacted with conserved surface TvLPG epitopes in 27 isolates from pregnant women at their first prenatal visit. Conserved TvLPG epitopes were shown to be surface exposed by immunofluorescence. Sera collected from the same patients at the same time were assayed for specific antibodies. Serum and vaginal secretions from 33 T vaginalis-positive women had statistically higher IgG anti-TvLPG levels than age-matched and race-matched negative controls in the same clinical study (p<0.01). Vaginal IgA anti-TvLPG levels of the women with trichomoniasis were almost significantly higher than controls (p=0.055). Infected women with normal pregnancies had significantly higher vaginal IgG anti-TvLPG values than infected women with adverse outcomes of pregnancy. CONCLUSIONS: These antibody responses show that infected women can respond to the conserved TvLPG antigen. Since antibodies to trichomonad surface LPG protect in a bovine model of trichomoniasis, the role of these antibodies in the human disease should be investigated.

No serologic evidence for zoonotic canine respiratory coronavirus infections among immunocompetent adults.

Zoonotic diseases continue to emerge and threaten both human and animal health. Overcrowded shelters and breeding kennels create the perfect environment for amplified infectious disease transmission among dogs and present a critical opportunity for zoonotic pathogens to emerge and infect people who work in close contact with dogs. Coronaviruses' widespread prevalence, extensive host range, various disease manifestations and increased frequency of recombination events all underline their potential for interspecies transmission (Methods Mol. Biol. 2008, 454, 43). The objectives of this study were to determine whether people with occupational contact with dogs were more likely to have antibodies against canine respiratory coronavirus (CRCoV) compared to persons with no dog exposure. A seroepidemiological cohort study was completed, for which 302 canine-exposed and 99 non-canine-exposed study subjects enrolled in the study by providing a serum sample and completing a self-administered questionnaire. A competitive enzyme-linked immunosorbent assay (ELISA) was developed to detect human antibodies against CRCoV while controlling for cross-reacting antibodies against the human coronavirus OC43. All study subjects were negative for antibodies against CRCoV by this competitive ELISA. This study supports the premise that humans are not at risk for CRCoV infections; however, infrequent cross-species transmission of CRCoV cannot be ruled out.

Prevalence, antibiotic resistance and molecular characterisation of Staphylococcus aureus in pigs at agricultural fairs in the USA.

Fairs and petting zoos have been associated with outbreaks of zoonotic disease. Previously, the presence of meticillin-resistant Staphylococcus aureus (MRSA) was documented in commercial pigs; therefore, it was hypothesised that antibiotic-resistant S aureus may also occur in pigs exhibited at agricultural fairs. To test this hypothesis, 157 pigs were swabbed at two state fairs in 2008 to 2009. Both nares were sampled and cultures were grown in enrichment broth, then plated onto selective MRSA plates and blood plates. S aureus was confirmed using phenotypic and molecular methods, and was analysed using spa typing, gene-specific polymerase chain reaction and antibiotic susceptibility testing. The presence of S aureus was confirmed in samples collected from pigs exhibited at USA pig shows. Twenty-five of 157 (15.9 per cent) samples were positive for S aureus. Two isolates (8 per cent) were resistant to meticillin; 23/25 (92 per cent), 14/25 (56 per cent) and 15/25 (60 per cent) were resistant to tetracycline, erythromycin and clindamycin, respectively. spa typing revealed multiple isolates of spa type t034 (9/25, 36 per cent) and t337 (7/25, 28 per cent) and singletons of t002, t209, t526, t1236, t1334, t1683, t3075, t5784 and t5883. These results verify the presence of antibiotic-resistant S aureus in pigs exhibited at USA fairs, suggesting that pigs are a potential reservoir for S aureus within this environment.

Evidence of previous avian influenza infection among US turkey workers.

The threat of an influenza pandemic is looming, with new cases of sporadic avian influenza infections in man frequently reported. Exposure to diseased poultry is a leading risk factor for these infections. In this study, we used logistic regression to investigate serological evidence of previous infection with avian influenza subtypes H4, H5, H6, H7, H8, H9, H10, and H11 among 95 adults occupationally exposed to turkeys in the US Midwest and 82 unexposed controls. Our results indicate that farmers practising backyard, organic or free-ranging turkey production methods are at an increased risk of infection with avian influenza. Among these farmers, the adjusted odds ratios (ORs) for elevated microneutralization assay titres against avian H4, H5, H6, H9, and H10 influenza strains ranged between 3.9 (95% CI 1.2-12.8) and 15.3 (95% CI 2.0-115.2) when compared to non-exposed controls. The measured ORs were adjusted for antibody titres against human influenza viruses and other exposure variables. These data suggest that sometime in their lives, the workers had been exposed to low pathogenicity avian influenza viruses. These findings support calls for inclusion of agricultural workers in priority groups in pandemic influenza preparedness efforts. These data further support increasing surveillance and other preparedness efforts to include not only confinement poultry facilities, but more importantly, also small scale farms.

Facing pandemic influenza threats: the importance of including poultry and swine workers in preparedness plans.

Recent research has shown that poultry and swine workers, especially those with intense exposures, are at increased risk of zoonotic influenza virus infections. In multiple studies, US poultry workers and poultry veterinarians have evidence of previous infections with avian influenza virus. Similarly, US swine workers have strong evidence of previous and acute infections with swine influenza viruses. Mathematical modeling has demonstrated that such workers may accelerate the spread of pandemic viruses in their rural communities. Because these workers may contribute to the novel generation of viruses and serve as a bridging population in the cross-species sharing of influenza viruses, it seems prudent to include poultry and swine workers in influenza preparedness programs. Possible preventive and control interventions include special education programs to increase workers' use of personal protective equipment such as gloves, increased surveillance for influenza viruses among workers and their animals, recommendations that workers seek medical attention should they develop influenza-like illness, and workers' priority receipt of annual and pandemic influenza vaccines.

The importance of including swine and poultry workers in influenza vaccination programs.

Sensing the threat of an influenza pandemic, many countries are developing influenza pandemic prevention and control strategies. Such plans often focus efforts on detecting outbreaks and protecting leaders, health-care workers, and outbreak responders. Considering recent research, we argue that prevention plans should also include swine and poultry workers. Ignoring these workers could result in an increased probability of generating novel viruses, as well as the acceleration of a pandemic's morbidity and mortality.

Mortality among US and UK veterans of the Persian Gulf War: a review.

Mortality data on Gulf War veterans was reviewed as a means of evaluating the long term consequences of the war. Studies were located from searches of Medline, Proceedings of the Conference on Federally Sponsored Gulf War Veterans' Illnesses Research, Proceedings of the American Public Health Association Annual Meetings, Annual Reports to Congress, and personal contacts with knowledgeable investigators. Data on study design, methods, and results were obtained from published studies of both US and UK veterans who served in the Persian Gulf. The methodology and results of studies are summarised and evaluated. Additional research recommendations based on reviewed studies are presented. It is concluded that in both US and UK studies, mortality from external causes was higher, while mortality from all illnesses was lower among Gulf War veterans in comparison to those of non-Gulf War veterans. Increased mortality from external causes is consistent with patterns of postwar mortality observed in veterans of previous wars. Further follow up of Gulf War veterans and their controls is warranted for evaluating the mortality risk from diseases with longer latency periods.

The Department of Defense Birth Defects Registry: overview of a new surveillance system.

BACKGROUND: The U.S. Department of Defense (DoD) is challenged with monitoring and protecting the health and wellbeing of its service members. The growing number of women on active duty and the diverse hazardous exposures associated with military service make reproductive health issues a special concern of DoD. To address this concern, the DoD Birth Defects Registry was established at the DoD Center for Deployment Health Research located at the Naval Health Research Center, San Diego, California. METHODS: The registry captures comprehensive data on healthcare utilization to calculate the prevalence of birth defects in the children of military beneficiaries. Population-based electronic surveillance is supplemented by active case validation efforts. RESULTS: Since its establishment in 1998, the registry has captured data on more than 90,000 births that occur in military families each year. Detailed analyses, to include linking registry data with military occupational exposure data (e.g., anthrax vaccination), are underway. CONCLUSIONS: The DoD Birth Defects Registry provides important reproductive health information on the geographically dispersed military population. This program is expected to complement civilian public health programs and be especially valuable to military members and their families.

Prospective study of respiratory infections at the U.S. Naval Academy.

Midshipmen at the U.S. Naval Academy have recently suffered epidemics of upper respiratory tract infections. Seeking to determine cause, in June 1998 we enrolled 1,243 (99.5%) of 1,249 new midshipmen (plebes) and followed them during their first 11 months of training. Eighty-five plebes sought medical attention for acute respiratory disease. Using culture, serologic studies, and polymerase chain reaction, considerable evidence for respiratory pathogen infection was found among the ill subjects: Chlamydia pneumoniae in 41 (52.6%), Mycoplasma pneumoniae in 19 (25.3%), influenza in 11 (14.2%), Streptococcus pneumoniae in 6 (7.3%), and adenovirus in 1 (1.2%). Additionally, 873 (81%) the 1,077 plebes who completed an end-of-year questionnaire complained of having one or more respiratory symptoms (> 12 hours) during their first year of school. Of these, 132 (15%) reported that the symptoms significantly affected their performance. Study results suggest that respiratory infections were frequent, had a significant adverse impact on training, and were often attributable to bacterial pathogens.

Randomized, placebo-controlled clinical trial of oral azithromycin prophylaxis against respiratory infections in a high-risk, young adult population.

Military Special Forces trainees undergo intense psychological and physical stressors that often lead to respiratory infection. During 1998-2000, 477 Navy Special Forces trainees were enrolled in a double-blind trial of oral azithromycin (1 g given weekly) plus a placebo injection, compared with benzathine penicillin G (1.2 million U) plus azithromycin placebo tablets. Among the 464 subjects with complete data, 44 developed acute respiratory infection (20 with pneumonia) during the 2 weeks of most intense training; of these subjects, 12 (27.3%) had evidence of Chlamydia pneumoniae infection and 7 (15.9%) had evidence of Mycoplasma pneumoniae infection. Trainees who received azithromycin were less likely than were trainees who received benzathine penicillin G to develop acute respiratory infection (risk ratio, 0.50; 95% confidence interval [CI], 0.28-0.92) and less likely at the end of training to report episodes of breathing difficulty (odds ratio [OR], 0.59; 95% CI, 0.34-1.01) or sore throat (OR, 0.66; 95% CI, 0.41-1.05). Compared with benzathine penicillin G prophylaxis, weekly oral azithromycin was superior in preventing respiratory infection in this population at transient high risk.

History of respiratory illness at the U.S. Naval Academy.

Throughout history, respiratory diseases have been a frequent cause of morbidity in U.S. populations. Because of stress, crowding, and naïve immune systems, military training populations are particularly prone to acute respiratory disease epidemics. An examination of the history of respiratory illness at the U.S. Naval Academy revealed that, in the earliest decades at the school, respiratory illness was a primary cause of both disease and mortality. With the advent of antibiotics and vaccines, most respiratory disease mortality has been reduced. However, even today, morbidity remains significant. Health concerns regarding respiratory diseases are heightened by emerging and reemerging respiratory disease agents that have increased antibiotic resistance and/or increased virulence. Enhanced surveillance and rapid diagnostic capabilities, placed in military settings, will increase knowledge of the epidemiology of many respiratory diseases. These strategies can lead to earlier treatment and prevention measures, thus halting the further transmission of disease and decreasing both morbidity and mortality. During the most recent history of the Naval Academy, acute respiratory infections have remained a primary cause of medical morbidity.

Simplified microneutralization test for serotyping adenovirus isolates.

A simplified microneutralization procedure is described that uses an empirically determined virus challenge dose, a single dilution of antiserum, and observation of cytopathic effect to determine the adenovirus serotype. The simplified test has faster turnaround time and was 96% concordant with a confirmatory test using serial dilutions of type-specific sera. This method will find utility in high-volume serotyping work.

National Department of Defense Surveillance for Invasive Streptococcus pneumoniae: antibiotic resistance, serotype distribution, and arbitrarily primed polymerase chain reaction analyses.

To provide surveillance among US military personnel and their beneficiaries, 157 invasive Streptococcus pneumoniae clinical isolates were collected systematically from 7 large military hospitals between August 1997 and August 1999. The isolates were studied for antibiotic resistance, and 120 were serotyped and subjected to arbitrarily primed polymerase chain reaction (AP-PCR). Fifty (31.9%) of 157 isolates had intermediate or high-level resistance to penicillin, and 15.9% had multidrug resistance. The most common serotypes were 4, 6B, 9V, 14, 19F, and 23F. Those serotypes associated with penicillin resistance were 6B, 9V, 19A, and 19F. Most invasive disease cases were caused by serotypes included in the currently available 23- and 7-valent pneumococcal vaccines. By use of AP-PCR, 4 DNA groups were correlated with health care site (P< or =.0001). These results are valuable in assessing appropriate use of antibiotics and vaccines against S. pneumoniae in both military personnel and their families.

A modified rapid method of nucleic acid isolation from suspension of matured virus: applied in restriction analysis of DNA from an adenovirus prototype strain and a patient isolate.

This report describes a method for the isolation of nucleic acid from a suspension of matured virus. Nucleic acid (DNA) was isolated from a prototype strain of adenovirus type 7 and a clinical isolate of adenovirus type 7. Instead of the usual method of ultracentifugation, a filtration method was applied to concentrate the virus rapidly and nucleic acid was then isolated by a standard phenol/chloroform/isoamyl-alcohol extraction procedure. The DNA was found to be sufficiently purified to generate a reproducible restriction endonuclease digestion pattern. The clinical isolate of adenovirus type 7 revealed loss of restriction site for the endonuclease HindIII when compared with the prototype strain.

Outbreak of influenza in highly vaccinated crew of U.S. Navy ship.

An outbreak of influenza A (H3N2) occurred aboard a U.S. Navy ship in February 1996, despite 95% of the crew's having been appropriately vaccinated. Virus isolated from ill crew members was antigenically distinct from the vaccination strain. With an attack rate of 42%, this outbreak demonstrates the potential for rapid spread of influenza in a confined population and the impact subsequent illness may have upon the workplace.