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Background: Pneumococci and nontypeable Haemophilus influenzae (NTHi) often cocolonize children. The impact of species interactions on disease risk across the upper respiratory mucosa is not known., Methods: We analyzed data from 4104 acute conjunctivitis (AC) cases, 11 767 otitis media (OM) cases, and 1587 nasopharyngeal specimens collected from Israeli children before pneumococcal conjugate vaccine introduction. We compared pneumococcal serotype distributions with NTHi present and absent, and compared single-species and mixed-species rates of serotype-specific progression from colonization to AC and OM., Results: Pneumococcal serotypes causing single-species OM (NTHi absent) were less diverse than colonizing serotypes and also less diverse than those causing mixed-species OM; colonizing and OM-causing pneumococcal serotype distributions were more similar to each other with NTHi present than with NTHi absent. In contrast, serotype diversity did not differ appreciably between colonizing and AC-causing pneumococci, regardless of NTHi co-occurrence. The similarity of colonizing and AC-causing pneumococcal serotype distributions was consistent in the presence and absence of NTHi. Differences in rates that pneumococcal serotypes progressed from colonization to disease were reduced in both AC and OM when NTHi was present., Conclusions: Interactions with NTHi may alter progression of pneumococcal serotypes to diseases of the upper respiratory mucosa in a site-specific manner., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Purpose: Bacterial conjunctivitis is a major problem in ocular health. Little is known about protective immune effectors in the conjunctiva. We evaluated whether opsonic antibody to the conserved surface/capsular polysaccharide poly-N-acetyl glucosamine (PNAG) expressed by Streptococcus pneumoniae and Staphylococcus aureus was protective against bacterial conjunctivitis, as well as an antibody to the Pseudomonas aeruginosa surface polysaccharide alginate., Methods: Bacteria were injected directly into the conjunctivae of either A/J mice or into conjunctivae of wild type C57Bl/6 mice for comparisons to responses of recombination activating gene 1-knock out (RAG 1 KO) or germ-free mice in the C57Bl/6 genetic background. Human IgG1 monoclonal antibodies (MAb) to either PNAG or alginate were administered as follows: direct injection of 10 μg into the conjunctivae or topical application onto the cornea 4, 24, and 32 hours post infection; or intraperitoneal injection of 200 μg 18 hours prior to and then 4, 24, and 32-hours postinfection. After 48 hours, eyes were scored for pathology, mice were euthanized, and CFU/conjunctiva was determined., Results: All methods of antibody administration reduced S. pneumoniae, S. aureus, or P. aeruginosa pathology and bacterial levels in the conjunctivae. Histopathologic analysis showed severe inflammatory cell infiltrates in conjunctivae of mice treated with control MAb, whereas immune mice showed only very mild cellular infiltration. The protective effect of MAb to PNAG was abolished in RAG 1 KO and germ-free mice., Conclusions: Antibodies to both PNAG and alginate demonstrated therapeutic efficacy in models of S. pneumoniae, S. aureus, and P. aeruginosa conjunctivitis, validating the protective capacity of antibodies to surface polysaccharides in distinct ocular tissues.

The recent emergence of the poultry bacterial pathogen Mycoplasma gallisepticum (MG) in free-living house finches ( Haemorhous mexicanus ), which causes mycoplasmal conjunctivitis in this passerine bird species, resulted in a rapid coevolutionary arms-race between MG and its novel avian host. Despite extensive research on the ecological and evolutionary dynamics of this host-pathogen system over the past two decades, the immunological responses of house finches to MG infection remain poorly understood. We developed seven new probe-based one-step quantitative reverse transcription polymerase chain reaction assays to investigate mRNA expression of house finch cytokine genes ( IL1B, IL6, IL10, IL18, TGFB2, TNFSF15 , and CXCLi2 , syn. IL8L ). These assays were then used to describe cytokine transcription profiles in a panel of 15 house finch tissues collected at three distinct time points during MG infection. Based on initial screening that indicated strong pro-inflammatory cytokine expression during MG infection at the periorbital sites in particular, we selected two key house finch tissues for further characterization: the nictitating membrane, i.e., the internal eyelid in direct contact with MG, and the Harderian gland, the secondary lymphoid tissue responsible for regulation of periorbital immunity. We characterized cytokine responses in these two tissues for 60 house finches experimentally inoculated either with media alone (sham) or one of two MG isolates: the earliest known pathogen isolate from house finches (VA1994) or an evolutionarily more derived isolate collected in 2006 (NC2006), which is known to be more virulent. We show that the more derived and virulent isolate NC2006, relative to VA1994, triggers stronger local inflammatory cytokine signaling, with peak cytokine expression generally occurring 3-6 days following MG inoculation. We also found that the extent of pro-inflammatory interleukin 1 beta signaling was correlated with conjunctival MG loads and the extent of clinical signs of conjunctivitis, the main pathological effect of MG in house finches. These results suggest that the pathogenicity caused by MG infection in house finches is largely mediated by host pro-inflammatory immune responses, with important implications for the dynamics of host-pathogen coevolution.

Background: Bacterial conjunctivitis is a common reason for children to be seen in pediatric practices. A correct diagnosis is important so that appropriate treatment can be instituted., Objective: To provide an update on the evaluation, diagnosis, and treatment of bacterial conjunctivitis in children., Methods: A PubMed search was completed in Clinical Queries using the key term "bacterial conjunctivitis". Patents were searched using the key term "bacterial conjunctivitis" from www.freepatentsonline.com and www.google.com/patents., Results: In the neonatal period, bacterial conjunctivitis is rare and the most common cause of organism is Staphylococcus aureus, followed by Chlamydia trachomatis. In infants and older children, bacterial conjunctivitis is most often caused by Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis. Clinically, bacterial conjunctivitis is characterized by a purulent eye discharge, or sticky eyes on awakening, a foreign body sensation and conjunctival injection (pink eye). The diagnosis is made clinically. Cultures are unnecessary. Some authors suggest a watchful observation approach as most cases of bacterial conjunctivitis are self-limited. A Cochrane review suggests the use of antibiotic eye drops is associated with modestly improved rates of clinical and microbiological remission as compared to the use of placebo. Various investigators have also disclosed patents for the treatment of conjunctivitis., Conclusion: The present consensus supports the use of topical antibiotics for bacterial conjunctivitis. Topical antibiotics shorten the course of the disease, reduce discomfort, prevent person-to-person transmission and reduce the rate of reinfection., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Leptospirosis is potentially a fatal zoonosis acquired by contact of skin and mucosal surfaces with soil and water contaminated with infected urine. We analyzed the outcome of infection of C3H/HeJ mice with Leptospira interrogans serovar Copenhageni using an enzootic mode of transmission, the conjunctival route. Infection led to weight loss and L. interrogans dissemination from blood to urine, and spirochetes were detected in blood and urine simultaneously. The infectious dose that led to consistent dissemination to kidney after conjunctival infection was ∼10 8 leptospires. Interestingly, a lower number of spirochetes appeared to colonize the kidney, given that we quantified ∼10 5 and ∼10 leptospires per μl of urine and per μg of kidney, respectively. Leptospira-specific IgM and IgG were detected at 15 days postinfection, and isotyping of the Ig subclass showed that the total IgG response switched from an IgG1 response to an IgG3 response after infection with L. interrogans Histological periodic acid-Schiff D staining of infected kidney showed interstitial nephritis, mononuclear cell infiltrates, and reduced size of glomeruli. Quantification of proinflammatory immunomediators in kidney showed that keratinocyte-derived chemokine, macrophage inflammatory protein 2, RANTES, tumor necrosis factor alpha, gamma interferon, and interleukin-10 were upregulated in infected mice. We show that the kinetics of disease progression after infection via the ocular conjunctiva is delayed compared with infection via the standard intraperitoneal route. Differences may be related to the number of L. interrogans spirochetes that succeed in overcoming the natural defenses of the ocular conjunctiva and transit through tissue., (Copyright © 2017 American Society for Microbiology.)

Purpose: To investigate latent conjunctival Chlamydia trachomatis (CT) and Bacteroides fragilis (BF) infections as potential risk factors for posttrabeculectomy bleb failure., Patients and Methods: This retrospective observational study included 50 primary open-angle glaucoma eyes of 50 patients who were submitted to trabeculectomy without cytostatics from September 2010 to June 2011 and were followed up for at least a year. Preoperatively, conjunctival scrapings were taken and their specimens subjected to polymerase chain reaction, direct fluorescent assay and cell culture testing for CT, and culture for BF on blood agar medium. Serum CT-specific IgG and IgA and tear interleukin (IL)-1β and IL-8 concentrations were measured with enzyme-linked immunosorbent assay. We defined bleb failure as intraocular pressure >21 mm Hg with antiglaucoma medications, resulting from reduced bleb filtration capacity due to bleb fibrosis, fistula obstruction, flattened bleb, or encapsulated bleb, and no earlier than 2 weeks after surgery. At the time of the reintervention, a scleroconjunctival biopsy was obtained for histopathology (including direct fluorescent assay testing for CT). Eyes were divided into a failure group and a nonfailure group, depending on whether they developed bleb failure (required reintervention) or not within a follow-up year., Results: In the failure group (n=18), the frequencies of detection of CT and BF in conjunctival specimens were 27.8% and 66.7%, respectively, versus 0% and 9.4% in the nonfailure group (n=32). CT and BF were detected in 11.1% and 11.1%, respectively, of scleroconjunctival biopsies. IgG and IgA seropositivity to CT was found in 66.7% and 33.3%, respectively, of the failure group patients, versus 9.4% and 0% of the nonfailure group patients. Tear IL-1β and IL-8 levels were markedly elevated in the failure group (468.83±80.43 and 107.89±15.11 pg/mL, respectively) versus the nonfailure group (22.34±5.43 and 9.34±2.83 pg/mL, respectively)., Conclusion: Being a contributor to low-grade conjunctival inflammation, latent conjunctival CT, and BF infections in primary open-angle glaucoma patients represent risk factors for posttrabeculectomy bleb failure.

Tests for the presence of pathogen DNA or antibodies are routinely used to survey for current or past infections. In diseases that emerge following a host jump estimates of infection rate might be under- or overestimated. We here examine whether observed rates of infection are biased for a non-focal host species in a model system. The bacterium Mycoplasma gallisepticum is a widespread pathogen in house finches (Haemorhous mexicanus), a fringillid finch, but an unknown proportion of individuals of other songbird species are also infected. Our goal is to determine the extent to which detection of M. gallisepticum DNA or antibodies against the bacteria in a non-fringillid bird species is over- or underestimated using black-capped chickadees Poecile atricapillus, a species in which antibodies against M. gallisepticum are frequently detected in free-living individuals. After keeping black-capped chickadees in captivity for 12 weeks, during which period the birds remained negative for M. gallisepticum, four were inoculated with M. gallisepticum and four were sham inoculated in both eyes to serve as negative controls. Simultaneously we inoculated six house finches with the same isolate of M. gallisepticum as a positive control. All inoculated birds of both species developed infections detectable by qPCR in the conjunctiva. For the 6 weeks following inoculation we detected antibodies in all M. gallisepticum-inoculated house finches but in only three of the four M. gallisepticum-inoculated black-capped chickadees. All house finches developed severe eye lesions but none of the black-capped chickadees did. Modeling the Rapid Plate Agglutination test results of black-capped chickadees shows that the rate of false-positive tests would be not more than 3.2%, while the estimated rate of false negatives is 55%. We conclude that the proportion of wild-caught individuals in which we detect M. gallisepticum-specific antibodies using Rapid Plate Agglutination is, if anything, substantially underestimated.

Aggression can alter infectious disease dynamics through two, non-exclusive mechanisms: 1) increasing direct contact among hosts and 2) altering hosts' physiological response to pathogens. Here we examined the latter mechanism in a social songbird by manipulating intraspecific aggression in the absence of direct physical contact. We asked whether the extent of aggression an individual experiences alters glucocorticoid levels, androgen levels, and individual responses to infection in an ecologically relevant disease model: house finches (Haemorhous mexicanus) infected with Mycoplasma gallisepticum (MG). Wild-caught male finches were housed in one of three settings, designed to produce increasing levels of aggression: 1) alone, with no neighbor ("no neighbor"), 2) next to a sham-implanted stimulus male ("sham neighbor"), or 3) next to a testosterone-implanted stimulus male ("testosterone neighbor"). Following one week of social treatment, focal males were experimentally infected with MG, which causes severe conjunctivitis and induces sickness behaviors such as lethargy and anorexia. While social treatment increased aggression as predicted, there were no differences among groups in baseline corticosterone levels, total circulating androgens, or responses to infection. Across all focal individuals regardless of social treatment, pre-infection baseline corticosterone levels were negatively associated with the severity of conjunctivitis and sickness behaviors, suggesting that corticosterone may dampen inflammatory responses in this host-pathogen system. However, because corticosterone levels differed based upon population of origin, caution must be taken in interpreting this result. Taken together, these results suggest that in captivity, although aggression does not alter individual responses to MG, corticosterone may play a role in this disease., (© 2014 Wiley Periodicals, Inc.)

When wild animals become infected, they still must cope with the rigors of daily life, and, thus, they still can be exposed to acute stressors. The suite of physiological responses to acute stress includes modifying the innate immune system, but infections can also cause similar changes. We examined the effects of an acute stressor (capture stress) on leukocyte abundance and bacteria-killing ability (BKA) in wild birds (house finches Haemorhous mexicanus) with and without a naturally occurring infection (Mycoplasma gallisepticum) to determine whether infection alters the typical immune response to stress. Birds were captured and bled within 3 min (baseline sample) and then held in paper bags for 2 h and bled again (stress sample). From blood smears made at both time points, we obtained estimates of total white blood cell (WBC) counts and relative numbers of each cell. We also measured BKA of plasma at both time points. In uninfected birds (n = 26), total WBC count decreased by 30% over time, while in infected birds (n = 9), it decreased by 6%. Relative numbers of heterophils did not change over time in uninfected birds but increased in infected birds. Combined with a reduction in lymphocyte numbers, this led to a threefold increase in heterophil-lymphocyte values in infected birds after the stressor, compared to a twofold increase in uninfected birds. There was a nonsignificant tendency for BKA to decline with stress in uninfected birds but not in diseased birds. Collectively, these results suggest that infections can buffer the negative effects of acute stress on innate immunity.

We previously showed that Staphylococcus aureus and Pseudomonas aeruginosa stimulate IL-8 expression in human conjunctival epithelial cells through different signal transduction pathways. As in some cell types both the bacteria may induce the release of prostaglandin E2 (PGE2) and PGE2 may affect the expression of IL-8, we aimed at investigating whether in human conjunctival cells infected with S. aureus or P. aeruginosa the activation of IL-8 transcription was mediated by PGE2 and which were the underlying molecular mechanisms. We found that S. aureus, but not P. aeruginosa, triggered IL-8 activation by increasing COX-2 expression and PGE2 levels in a time-dependent manner. Overexpression of nucleotide-binding oligomerization domain-2 (NOD2) resulted to be essential in the enhancement of IL-8 induced by S. aureus. It dramatically activated c-jun NH2-terminal kinase (JNK) pathway which in turn led to COX2 upregulation and ultimately to IL-8 transcription. The full understanding of the S. aureus-induced biochemical processes in human conjunctival epithelium will bring new insight to the knowledge of the molecular mechanisms involved in conjunctiva bacterial infections and develop novel treatment aiming at phlogosis modulation., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Acute inflammation that arises during Pseudomonas aeruginosa-induced ocular infection can trigger tissue damage resulting in long term impairment of visual function, suggesting that the appropriate treatment strategy should include the use of anti-inflammatory agents in addition to antibiotics. We recently identified a potential target for modulation during ocular infection, macrophage migration inhibitory factor (MIF). MIF deficiency protected mice from inflammatory-mediated corneal damage resulting from acute bacterial keratitis. To gain a better understanding of the molecular mechanisms of MIF activity, we analyzed the oligomeric states and functional properties of MIF during infection. We found that in human primary corneal cells infected with P. aeruginosa, MIF is primarily in a homotrimeric state. Homotrimeric MIF levels correlated with the severity of infection in the corneas of infected mice, suggesting that the MIF homotrimers were the functionally active form of MIF. During infection, human primary corneal cells released more IL-8 when treated with recombinant, locked MIF trimers than when treated with lower MIF oligomers. MIF promoted P. aeruginosa-induced IL-8 responses via the formation of caveolin-1-rich "signaling hubs" in the corneal cells that led to elevated MAPK p42/p44 activation and sustained inflammatory signaling. These findings suggest that inhibiting homotrimerization of MIF or the functional activities of MIF homotrimers could have therapeutic benefits during ocular inflammation.

Objective: To evaluate efficacy of a recombinant Moraxella bovis pilin-cytotoxin-Moraxella bovoculi cytotoxin subunit vaccine to prevent naturally occurring infectious bovine keratoconjunctivitis (IBK)., Animals: 107 beef steers., Procedures: 2 groups of calves were inoculated SC with an immunostimulating complex (ISCOM) matrix adjuvant (control group; n = 54) or a recombinant M bovis pilin-cytotoxin-M bovoculi cytotoxin subunit antigen with the ISCOM matrix adjuvant (vaccine group; 53); calves received booster injections 21 days later. Calves were examined once weekly for 16 weeks. Investigators and herd managers were not aware of the inoculum administered to each calf throughout the trial. Primary outcome of interest was the cumulative proportion of calves that developed IBK. Serum samples were obtained before inoculation (day 0) and on days 42 and 112. Serum hemolysin-neutralizing titers against native M bovis and M bovoculi cytotoxin were determined., Results: No difference was detected between groups for the cumulative proportion of calves that developed IBK at weeks 8 and 16 after inoculation. Non-IBK-affected calves in the vaccine group had a significantly higher fold change in serum hemolysin-neutralizing titer against native M bovoculi cytotoxin from day 0 to 42 compared to control calves., Conclusions and Clinical Relevance: The M bovis pilin-cytotoxin-M bovoculi cytotoxin subunit vaccine with the ISCOM matrix adjuvant was not effective at preventing naturally occurring IBK. It is likely that the incorporation of additional protective antigens in a recombinant Moraxella spp subunit vaccine will be required to yield a product that can be used for effective immunization of cattle against IBK.

The host-pathogen interaction drives infectious disease dynamics at the individual, population and community levels. Here I present and analyze a model of the vertebrate immune response to mycoplasma infections, and use it to identify which pathogen and host immune characteristics drive patterns of Mycoplasma gallisepticum (MG) infections in the house finch (Carpodacus mexicanus) and other passerine birds. I also address which host and pathogen characteristics most affect host infectiousness and survival. These results imply that much of the observed variation in the house finch likely arises from variation among birds in the effectiveness of their non-specific immune response to MG, and that the host and pathogen characteristics most likely to influence host infectiousness and survival are the intrinsic pathogen growth rate, the strength and efficiency of the non-specific immune response and characteristics affecting the effectiveness of the specific response. These findings suggest that molecular-level study of how MG and other mycoplasmas interact with a host's non-specific and inflammatory responses should reveal much about the relationships between host infectiousness, pathogen load, and disease symptoms in these systems., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Mycoplasma gallisepticum (MG) has become a common cause of conjunctivitis in free-living house finches (Carpodacus mexicanus) since its emergence in the early 1990s. To date, temporal and spatial genotypic variation in MG has been documented, but phenotypic variation in pathogenicity and immunogenicity has not been examined. House finches were inoculated with MG isolates Virginia (VA)1994, California (CA)2006, or North Carolina (NC)2006, which were cultured from free-living house finches with conjunctivitis in 1994, 2006, and 2006, respectively. Infection with NC2006 resulted in the most severe eye lesions, highest pathogen loads, and highest levels of pathogen-specific lachrymal and serum antibodies. Infection with CA2006 caused the least severe eye lesions, lowest pathogen load, and lowest levels of antibodies. A small number of birds in each group developed protracted, severe disease in spite of robust antibody responses, suggesting that immunopathology may contribute to the lesions. Immunoblot analyses indicated that isolates are antigenically similar; thus, there may be partial cross-protection if a house finch encounters two or more strains of MG throughout the course of its lifetime. This study provides evidence that MG strains or strain variants circulating in house finch populations vary in their ability to cause disease, induce antibody responses, and persist in the host., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The aim of this study was to evaluate the incidence and morbidities of Chlamydia trachomatis infections in newborn infants. Tissue culture and direct immunofluorescence (DIF) tests were used to detect the presence of nasopharyngeal C. trachomatis infection in 35 preterm and 21 healthy term neonates. All infants were followed up clinically for 3 months, and enzyme-linked immunosorbent assay analysis for serum antichlamydial IgG and IgM was performed on day 15 and week 6. Tissue culture and/or DIF studies showed that 10 of the preterm infants (28.57%), but none of the term infants, were C. trachomatis-positive. The sensitivities of DIF and tissue culture were 40% and 70%, respectively, demonstrating the diagnostic superiority of tissue culture tests for detecting C. trachomatis. Only one asymptomatic preterm infant was found to be positive for antichlamydial antibodies at the 6th week. All C. trachomatis-positive infants were given macrolide antibiotics for 14 days. The study showed that male infants were more frequently infected, but types of delivery, mean gestational ages, mean birth weights, and the need for mechanical ventilation were similar in C. trachomatis-infected and uninfected preterm infants. However, the duration of oxygen treatment was longer in infected preterm infants. Clinical conjunctivitis was more frequent in C. trachomatis-infected infants (60%) than in uninfected infants (24%). C. trachomatis-positive infants had pneumonia more frequently; however, all patients with pneumonia were negative for antichlamydial IgM and IgG antibodies. Macrolide treatment for 2 weeks for nasopharyngeal C. trachomatis positivity may have prevented C. trachomatis related pneumonia, but it may not have significantly influenced the risk of pneumonia caused by other agents. Chlamydial infections may lead to early and late respiratory problems in preterm infants. Nasopharyngeal screening may help physicians detect C. trachomatis infections and provide a means of early diagnosis in this vulnerable patient group.

Aim: Improvement of therapy of chronic ophthalmic infectious diseases during assessment of functioning of different arms of immune system., Materials and Methods: Three hundred and fifty patients with chronic red-eye syndrome were tested by immunofluorescence assay on the presence of antigens of herpesviruses, adenoviruses and Chlamydia in samples from conjunctiva. Expression of 11 cytokines' genes was measured in peripheral blood mononuclear cells by reverse transcription polymerase chain reaction. Production of IFN-alpha and IFN-gamma, levels of serum and spontaneously produced interferon as well as level of susceptibility to the range of immunomodulating preparations were measured during study of interferon status in whole blood cells. Study of parameters of cytokine, interferon and immune statuses was performed in 70 patients. Counts of T- and B-lymphocytes, T-helpers, NK-cells as well as level of circulating immune complexes were measured during study of immune status., Results: Antigens of herpes simplex virus and adenoviruses were detected in samples from conjunctiva in 27% (95 persons) and 36% (126 persons) of patients respectively. Enhanced level of expression of several cytokines (IL-2, IL-4) in studied patients compared with healthy volunteers was observed. Expression levels of IL-12 and TNF-alpha mRNAs were, in opposite, in 2 - 3 times lower. Disorder of IFN-alpha and IFN-gamma synthesis on post-transciption level was observed in 60 - 90% of patients. Decrease of absolute numbers of total T-lymphocytes and T-helpers as well as increase of absolute number of NK-cells was noted in 20%, 25%, and 27% of patients respectively., Conclusion: Assignment of individually oriented antiviral, antibacterial and immunomodulating therapy allowed to mitigate intensity of clinical symptoms in 30 -60% of patients with chronic persistent infections of anterior segment of eye.

Conjunctival swabs taken from a two-month-old kitten showing ocular discharge were found to be positive for Chlamydophila felis by PCR and isolation. The cat was treated with topical 1% tetracycline ophthalmic ointment twice a day for 60 days. At the end of the treatment, the cat showed no ocular signs and conjunctival swabs resulted PCR and isolation negative for C. felis. Forty days later, the ocular discharge recurred and C. felis was isolated from conjunctival swabs taken from both the cat's eyes. Twenty days of doxycycline systemic treatment at 10 mg/kg once daily was started. The treatment resulted in a complete clinical recovery after a few days. C. felis was not isolated or amplified on the 10th day after beginning the treatment. The cat's conjunctival swabs were also PCR and isolation negative on the 10th, 30th, 60th, 90th, 120th and 240th days after the end of therapy.

Fourteen house finches were reinoculated (re-exposed) with 0.05 ml (3.24x10(5) colony forming units/ml) of Mycoplasma gallisepticum (MG) in the conjunctival sac of each eye. All birds used in this reinoculation study had recovered from previous infection between 27 and 83 days after inoculation. Recovery was based on the absence of clinical signs of conjunctivitis and/ or the inability to detect MG in conjunctival or choanal samples. Birds were maintained in individual cages under controlled environmental conditions at temperature 21-24 C, relative humidity 70%, and a light cycle adjusted to ambient values. They were divided into three groups, (A, B, and C). Five birds each were reinoculated 219 days (7.3 mo, group A) and 314 days (10.47 mo, group B) after the original infection. The final group of four birds was reinoculated at 425 days after experimental infection (14.17 mo, group C). Although the birds were randomly assigned to the three groups, the duration of the disease state (number of days until clinical signs last observed) during initial infection differed: group A mean=37.0+/-SE 4.549, group B mean=63.6+/-SE 6.306, group C mean=42.75+/-SE 2.750; analysis of variance F2,11=8.17, P=0.007. Within 24 hr after reinoculation six of the 14 experimental birds had developed some clinical signs of MG-induced conjunctivitis. At 3 days after reinoculation, 12 of the 14 birds had unilateral or bilateral conjunctivitis. The duration of clinical signs in the reinoculated individuals was significantly shorter than with their previous infection. These results suggest that the birds were able to mount a rapid and strong immune response following re-exposure. However, they were susceptible to reinfection and developed disease, suggesting that reinfection or perhaps even recurrence of infection and disease could occur in the free-ranging population. This may represent an important component in the epidemiology of this disease in house finches.

Conjunctivitis in house finches (Carpodacus mexicanus), caused by Mycoplasma gallisepticum (MG), was first reported in 1994 and, since this time, has become endemic in house finch populations throughout eastern North America. Although the house finch is most commonly associated with MG-related conjunctivitis, MG has been reported from other wild bird species, and conjunctivitis (not confirmed as MG related) has been reported in over 30 species. To help define the host range of the house finch strain of MG and to better understand the effect of MG on other host species, we monitored a community of wild birds for exposure to MG and conducted experimental infections on nine avian species. For the field portion of our study, we conducted a 9-mo survey (August 2001 to April 2002) of wild avian species in a peri-urban environment on the campus of Auburn University. During this time 358 birds, representing 13 different families, were sampled. No clinical signs of mycoplasmosis were observed in any bird. Thirteen species from nine families had positive agglutination reactions for antibodies to MG, but all birds tested negative by polymerase chain reaction (PCR). Three mourning doves were PCR-positive for MG, but antibodies to MG were not detected. In the experimental infections, we exposed seven native avian species and two cage-bird species to MG (May 2000 to June 2002). After exposure, clinical disease was seen in all four species from the family Fringillidae and in eastern tufted titmice (Baeolophus bicolor). In addition, three other species were infected without clinical signs, suggesting that they may represent potential MG reservoirs.

We examine the role of host seasonal breeding, host seasonal social aggregation and partial immunity in affecting wildlife disease dynamics, focusing on the dynamics of house finch conjunctivitis (Mycoplasma gallisepticum (MG) in Carpodacus mexicanus). This case study of an unmanaged emerging infectious disease provides useful insight into the important role of seasonal factors in driving ongoing disease dynamics. Seasonal breeding can force recurrent epidemics through the input of fresh susceptibles, which will clearly affect a wide variety of wildlife disease dynamics. Seasonal patterns of social aggregation and foraging behaviour could change transmission dynamics. We use latitudinal variation in the timing of breeding, and social systems to model seasonal dynamics of house finch conjunctivitis across eastern North America. We quantify the patterns of seasonal breeding, and social aggregation across a latitudinal gradient in the eastern range of the house finch, supplemented with known field and laboratory information on immunity to MG in finches. We then examine the interactions of these factors in a theoretical model of disease dynamics. We find that both forms of seasonality could explain the dynamics of the house finch-MG system, and that these factors could have important effects on the dynamics of wildlife diseases generally. In particular, while either alone is sufficient to create recurrent cycles of prevalence in a population with an endemic disease, both are required to produce the specific semi-annual pattern of disease prevalence seen in the house finch conjunctivitis system.

Mycoplasma gallisepticum (MG) has caused an endemic upper respiratory and ocular infection in the eastern house finch (Carpodacus mexicanus) after the epidemic first described in 1994. The disease has been studied by a number of investigators at a population level and reports describe experimental infection in group-housed MG-free house finches. Because detailed observation and evaluation of individual birds in group-housed passerines is problematic, we studied individually housed house finches that were experimentally inoculated with the finch strain of MG in a controlled environment. To accomplish this, a study was conducted spanning the period of November 2001-April 2002 with 20 MG-free (confirmed by the rapid plate agglutination assay and polymerase chain reaction [PCR] assay) eastern house finches captured in the Cayuga Basin area of central New York (USA) in the summer of 2001. After a period of acclimatization and observation (12 wk), 20 finches were inoculated with a 0.05-ml aliquot of MG (3.24 x 10(5) colony-forming units/ml) via bilateral conjunctival sac instillations. Two additional finches acted as controls and were inoculated in the same manner with preservative-free sterile saline solution. After inoculation, all finches except the controls exhibited clinical signs of conjunctivitis within 2-6 days. The progression of the disease was evaluated by several methods, including PCR, behavioral observations, and physical examination including eye scoring, body weight, and body condition index. Over a period of 21 wk, MG-infected finches developed signs of disease and recovered (80%), developed signs of disease and progressed to become chronically infected (15%), or died (5%). We hypothesize that the high survival rate and recovery of these finches after infection was associated with the use of controlled environmental conditions, acclimatization, a high plane of nutrition, and low stocking (housing) density, all of which are factors documented to be important in the outcome of MG infections in domestic poultry and other species.

Since 1994 an epidemic of mycoplasmal conjunctivitis has spread throughout the eastern house finch (Carpodacus mexicanus) population leading to a significant decline in this population. The infection has not yet been reported from house finch populations west of the Great Plains. We hypothesized that the western population, like the eastern population, is susceptible to infection, and we tested this hypothesis by experimentally infecting house finches from Missoula, Montana (USA) with the house finch strain of Mycoplasma gallisepticum (MG). We compared the response of finches from Montana infected with MG to that of finches from Auburn, Alabama (USA) (October 1999-February 2000). Fifteen house finches from Montana were shipped to Auburn and quarantined for 6 wk at the Auburn University aviary. All birds were negative for MG antibodies when tested by serum plate agglutination assay and MG could not be detected in any bird by polymerase chain reaction. We tested two methods of inoculation, ocular inoculation and contact exposure to an infected finch. Seven house finches from Montana and four house finches from Alabama were infected by bilateral ocular inoculation with 20 microliters of a culture containing 1 x 10(6) color changing units of the house finch strain of MG. The remaining eight house finches from Montana were co-housed with a house finch from Alabama exhibiting mycoplasmal conjunctivitis. After exposure to the pathogen, all house finches became infected, regardless of origin or method of exposure, and all developed conjunctivitis. All birds seroconverted, and evidence of infection could be detected in every bird at some point during the course of disease. Our results suggest that house finches from the western United States are highly susceptible to infection with the house finch strain of MG.

Pseudomonas aeruginosa is the most common pathogen among contact lens-associated infections. This study investigated the response of the murine cornea to infection with an ocular strain of P. aeruginosa isolated from a subject with an inflammatory adverse response to contact lens wear termed CLARE. Although this bacterium was isolated in confluency (greater than 2000 cfu lens-1) from the lens at the time of the inflammatory episode, no infection of the cornea subsequently developed. Male C57BL/6J mice (20 per strain) had their corneas scratched with a 26 gauge needle (3 parallel 1.0 mm wounds in the left eye only). The incisions were centered over the pupillary axis and penetrated the epithelial cell basal lamina and into the superficial stroma. The CLARE strain was found to persist (viable bacteria could be cultured from corneal homogenates) up to 8 hr, as did the virulent control strain ATCC 19660. At 24 hr, only ATCC 19660 could be cultured, indicating an inability of the strain isolated from CLARE, Paer1, to persist in the eye consistent with the human inflammatory episode. Histological examination of the mouse tissue showed further differences between infection by the two strains. Infection with ATCC 19660 resulted in tissue necrosis and a large population of polymorphonuclear leukocytes (PMNs) recruited to the wound site. In contrast, during infection with the CLARE strain, PMN recruitment was reduced and temporally delayed. The CLARE strain grew as well as ATCC 19660 in vitro but produced less protease activity, in particular less elastase. The decreased PMN response and decreased protease production by the CLARE strain may have been responsible for the lack of ocular damage and apparent healing of the wound. P. aeruginosa strains are considered to be invasive or cytotoxic to corneal tissue, however this strain may represent a third inflammatory type consistent with its differing pathology., (Copyright 1998 Academic Press.)

Inflammatory processes are characterized by the dynamic influx of leukocytes. This leukocyte recruitment and activation is thought to be initiated by chemical signals including chemotactic factors. This study was designed to investigate the chemotactic activity in different tear types and bacteria isolated during adverse responses to contact lens wear. Chemotactic activity was determined by quantitating in vitro neutrophil migration using a microchemotaxis chamber. Results demonstrated that tears collected immediately after 8 hours sleep (P<0.001) and tears collected during adverse responses (P<0.001) showed significantly higher chemotactic activity compared to reflex tears. Specific neutralizing antibodies to IL-8, LTB4 and C5a were added to closed eye and adverse response tears. Pre-incubation of closed eye tears with antibodies to IL-8 showed a significant reduction in chemotactic activity (P<0.0001), whereas a significant reduction of PMN migration in adverse response tears was observed after pre-treatment with antibodies to LTB4 (P<0.0001). However no difference in chemotactic activity was observed after incubation with antibody to C5a or irrelevant antibody. Dot blots demonstrated that closed eye tears contained approximately 150 ng ml-1 IL-8 and adverse response tears contained 2 ng ml-1 IL-8. Most Gram negative bacteria isolated from contact lenses caused directed migration of PMNs. Addition of neutralizing antibody to LPS significantly abrogated the chemotactic activity of bacterial cells (P<0.001). Our findings provide evidence that IL-8 during eye closure, and bacterial chemotactic substances and LTB4 during contact lens induced adverse responses, are responsible for the recruitment of PMNs., (Copyright 1998 Academic Press Limited.)

In addition to the commonly reported ocular signs, Chlamydia psittaci infection of kittens resulted in fever, lethargy, lameness and reduction in weight gain following ocular instillation of virulent organisms. The appearance of these systemic signs was late with respect to the appearance of ocular symptoms and occurred simultaneously with increasing levels of chlamydia-specific IgG. Measurement of acute phase reactants and IL-6 in plasma indicated that both became elevated concurrent with or slightly after the appearance of fever and remained elevated after the fever began to resolve. Preliminary data also indicated that infectious C. psittaci was present in the blood stream during this time period. The results of ocular instillation of three different levels of C. psittaci (10(3.8), 10(2.8) and 10(1.5) TCID50) indicated that the frequency of infection and the severity of ocular signs were diminished in the group receiving the lowest dose. However, the magnitude of systemic disease was similar in all animals which exhibited clinical signs, irrespective of the dose administered. The immune response to infection included elementary body (EB)-specific lymphocyte proliferation as well as the development of EB-specific IgG and IgM antibodies. The predominant antibody response was to a 45 kDa protein, the major outer membrane protein (MOMP), lipopolysaccharide (LPS), a 58 kDa doublet and 32 and 16-19 kDa proteins.

Purpose: Tear IgE has been considered to play an important role in allergic conjunctivitis and the measurement of tear IgE concentrations can help to diagnose this condition. Locally produced IgE levels have been shown to be the largest contributor to the severity of allergic conjunctivitis., Methods: One hundred and thirteen allergic conjunctivitis patients (70 seasonal allergic conjunctivitis (SAC), 21 perennial allergic conjunctivitis (PAC), 22 vernal keratoconjunctivitis (VKC)), 14 bacterial conjunctivitis (BC) patients, 13 epidemic keratoconjunctivitis (EKC) patients and 18 normal controls were recruited. Tear samples were collected using the microcapillary method and tear IgE levels were measured using an immunoenzyme assay., Results: Tear IgE concentrations showed significant increases in the VKC (322.2 +/- 45.7 ng/ml), SAC (194.7 +/- 21.7 ng/ml) and PAC (134.8 +/- 23.1 ng/ml) groups when compared with controls (52.1 +/- 9.7 ng/ml, p < 0.01). No significant difference was found between EKC (97.2 +/- 11.7 ng/ml) and BC (92.6 +/- 13.8 ng/ml) groups and controls (p = 0.1)., Conclusions: Tear IgE concentrations showed a significant increase in allergic conjunctivitis patients when compared with controls. Our results suggest that measuring tear IgE concentrations can help to diagnose allergic conjunctivitis.

The first Danish case of Parinaud's oculoglandular syndrome, a manifestation of cat-scratch disease, is reported in a 35-year-old man presenting with an enlarged preauricular lymph node and an ipsilateral conjunctival granuloma. Surgical removal of the granulomatous lesion was followed by rapid healing. The diagnosis was verified by demonstrating a high antibody tire against Rochalimaea (Bartonella) henselae. On subsequent questioning the man gave a history of acquiring a kitten six weeks before his illness. The importance of eye examination in patients presenting with preauricular lymphadenopathy is emphasized.

The effect of conjunctival Mycoplasma bovoculi infection on local and systemic natural killer activity was studied in cattle. A standard in vitro assay against the mouse tumor cell line, YAC-1, was used to measure increases in effector cell activity. Local responses in the eye were investigated by examination of stained exfoliative conjunctival cells and tissue biopsies. An increase in systemic cytolytic activity was seen in infected calves, and maximal values were observed on the second day post infection (DPI). An elevation in the number of large granular lymphocytes was noted in the conjunctival samples, and maximal numbers were again observed at 2 days post infection. It is proposed that natural killer cell activity may play a role in the initial host responses of cattle to M. bovoculi infection.

Between 1981 and 1987 the authors saw 12 patients with Reiter's syndrome. Lesions included 6 cases of bilateral conjunctivitis in patients with chlamydial infection, 3 of unilateral serofibrinous iridocyclitis in patients with Yersinia enterocolitica, 1 case of bilateral iridocyclitis in a patient with positive chlamydial complement-binding reaction, 1 case of bilateral follicular conjunctivitis following acute gonococcal urethritis, and one case of unilateral serofibrinous iridocyclitis, in a patient with Ureaplasma urealyticum. Immunohistologic work-up of the conjunctival biopsy from the patient with Urea-plasma urealyticum urethritis revealed IgM deposits in the vascular endothelium of conjunctival vessels, C-3 deposits in the conjunctival stroma, and intercellular IgG in the conjunctival epithelium. Since Reiter's syndrome is interpreted as a sequela of secondary immune diseases following a primary infection that may persist in HLA-B27-positive patients, the patients were treated with both topical and systemic anti-infectious and anti-inflammatory agents.

We used a naturally occurring, Chlamydia psittaci-caused eye disease in guinea pigs, guinea pig inclusion conjunctivitis, as an animal model to understand both the immune response and the pathogenesis of chlamydial eye infections. When instilled into the conjunctival sac of guinea pigs that had been previously infected and were immune, viable chlamydiae or a Triton X-100-soluble extract of them produced a short-lived (12-48 hr) eye disease indistinguishable clinically and histologically from that observed during primary chlamydial eye infection. The clinical and histologic findings were consistent with those of ocular delayed hypersensitivity. Ocular delayed hypersensitivity was induced by primary chlamydial infection at mucosal sites other than conjunctival, such as vaginal and intestinal. Preliminary characterization of the hypersensitivity allergen shows that it is heat sensitive and common to the genus Chlamydia. The allergen is apparently not surface-exposed on chlamydiae and requires viable but not replicating organisms for activity. Our observation should be useful in understanding pathogenetic mechanisms of Chlamydia trachomatis-caused infections in humans, in particular those that produce chronic inflammatory diseases, such as blinding trachoma and urogenital diseases.

Chlamydia trachomatis was isolated from 21.5% (61/284 cases) of the patients with conjunctivitis seen in an eye clinic in Sapporo, Japan, during a recent 4-year period. The frequency was the highest in newborn babies and the 20- to 29-year-old age group. The early incidence of neonatal conjunctivitis suggested that transmission had occurred at delivery. Isolation by tissue culture is the most sensitive method for detection of this condition but the Micro Trak direct fluorescence antibody test is more practical. The detection of a specific IgG antibody and IgA antibody against chlamydia in human sera and in tears showed that patients with chlamydial conjunctivitis had the antibody before the onset of conjunctivitis.

A commercially available ELISA designed for the detection of C trachomatis in human urogenital specimens was compared with cell culture for the detection of Chlamydia psittaci in cat conjunctival swabs and in twofold dilutions of a cell culture pool of a feline strain of C psittaci. Cell culture was more sensitive than the ELISA test for detection of C psittaci.

Recurrent or persistent infections with Chlamydia trachomatis are thought to provide the antigenic stimulus for the chronic inflammation associated with blinding trachoma. We used the guinea pig model of inclusion conjunctivitis to identify chlamydial antigens that may be involved in this deleterious immune response. We purified from chlamydial elementary bodies a genus-specific 57-kD protein that elicited an ocular hypersensitivity response when placed topically onto the conjunctiva of ocular immune guinea pigs. This response was characterized by a predominantly mononuclear macrophage and lymphocyte cellular infiltrate of the submucosal epithelium. The clinical and histological findings were consistent with those of a delayed hypersensitivity response. These data demonstrated that the 57-kD chlamydial protein was a potent stimulator of ocular delayed hypersensitivity. Our findings may be critical to understanding the pathogenesis of the debilitating chlamydial diseases associated with chronic inflammation, such as trachoma and many urogenital syndromes.