Outbreak Of Infectious Keratoconjunctivitis Research Articles

Infectious keratoconjunctivitis in semi-domesticated reindeer (Rangifer tarandus tarandus): a questionnaire-based study among reindeer herders in Norway and Sweden

BackgroundThe effects of climate change, loss of pastureland to other land usage and presence of large carnivores are the main reasons for the increase in supplementary feeding of semi-domesticated reindeer (Rangifer tarandus tarandus) in Fennoscandia over the last decades. Feeding might expose reindeer to stress and increased animal-to-animal contact, leading to an increased risk of infectious disease transmission, such as infectious keratoconjunctivitis (IKC). As it can develop rapidly and be very painful, IKC is described as an important animal welfare concern and a potential source of economic loss. The aim of this study was to investigate the current presence of IKC and potential associations between IKC and supplementary feeding through an online questionnaire survey, distributed among reindeer herders in Norway and Sweden in 2021.ResultsSeventy-six reindeer herders (33 from Norway and 43 from Sweden) responded to the questionnaire, representing 6% and 4% of the registered reindeer herding groups in Norway and Sweden, respectively. Infectious keratoconjunctivitis was common, with 54 (71%) of the 76 herders that responded having observed clinical signs during the past 10 years. These signs were mainly observed as increased lacrimation, causing “wet cheeks”, but also as keratitis and conjunctivitis. Autumn and winter were the seasons in which IKC was observed most. The herders reported several measures, such as slaughter and isolation of affected reindeer, to counteract the spread of disease. The herding year 2019/2020 was associated with reports of outbreaks of IKC in herds as well as being the herding year where most herders (80%) had performed supplementary feeding. A significant association was found between IKC and feeding performed in an enclosure (odds ratio = 15.20), while feeding on free-range areas had a non-significant, negative, relationship with the appearance of IKC outbreaks (odds ratio = 0.29). Finally, there was a trend in the data suggesting that IKC affected calves especially.ConclusionsInfectious keratoconjunctivitis is a common disease, mainly observed in winter and autumn. It usually has mild to moderately severe clinical signs. Our results imply that IKC is associated with stress and feeding situations and that calves might be more susceptible than adults, however, this needs to be confirmed with further studies, preferably at an individual animal level.

Bacteria associated with infectious keratoconjunctivitis outbreak in confined lambs.

Introduction. Infectious keratoconjunctivitis is a significant ocular disease found in confined sheep. Little information about the aetiological agents and their antimicrobial susceptibility is available.Gap Statement. There is limited information on the aetiological agents involved in keratoconjunctivitis outbreaks in sheep.Aim. The present research aimed to determine the bacterial aetiological factors involved in an outbreak of infectious keratoconjunctivitis in confined lambs.Methodology. Ocular swabs were collected from 23 randomly selected lambs, which were classified into three groups according to the severity of the lesion: group I (N=6; no ocular involvement), group II (N=8; less severe injuries) and group III (N=9; more severe injuries). Isolation of aerobic bacteria and antimicrobial susceptibility tests were carried out. Molecular detection of Mollicutes was performed, and positive samples were tested to confirm the presence of the following species: Mycoplasma conjunctivae, Mycoplasma agalactiae and Mycoplasma mycoides subsp. capri.Results. Moraxella sp. and Mollicutes were detected in all groups, but we inferred that Moraxella sp. are only significant in the early stages of the disease. M. conjunctivae was detected in all tested groups, while M. agalactiae was detected in samples of group III only. One strain of Moraxella sp. was resistant to erythromycin and showed intermedite resistance to tetracycline.Conclusion. The presence of these species confirms their importance in the aetiology of this disease, and the low resistance profile observed in the studied farm suggested an increased cure success rate.

Isolation and characterization of Moraxella ovis from ovine infectious keratoconjunctivitis in a sheep farm of northern India

Infectious keratoconjunctivitis (IKC) in ruminants is an economically important infectious disease occurring worldwide. In sheep, Moraxella ovis has been frequently reported in disease outbreaks of IKC. In this study, isolation and molecular confirmation of M. ovis from IKC in sheep was reported for the first time in Uttar Pradesh. On blood agar, a narrow zone of haemolysis was noticed around the colonies and on staining confirmed the Gram negative diplococci. Aerobic nature of bacteria was confirmed by growth on the slant in triple sugar iron (TSI) medium. Catalase, oxidase and nitrate reduction tests yielded positive results. Antibiotic sensitivity test showed sensitivity to all the tested antibiotics. Polymerase chain reaction and partial sequencing of 16S ribosomal RNA gene showed 99% similarity to M. ovis in NCBI database. Serum agglutination test of infected animals indicated the possibility of M. ovis infection. The study suggests the need for further epidemiological studies to map the extentofthe problem intheregion.

Chlamydia pecorum Associated With an Outbreak of Infectious Keratoconjunctivitis in Semi-domesticated Reindeer in Sweden.

Infectious keratoconjunctivitis (IKC), the most common ocular disease in ruminants worldwide, has affected semi-domesticated Eurasian reindeer (Rangifer tarandus tarandus) for over 100 years, both as individual cases and in outbreaks affecting tens to hundreds of animals. Recurrent IKC outbreaks have been affecting a semi-domesticated reindeer herd in Östra Kikkejaure (Norrbotten county, Sweden) from 2014. The latest episode of these recurrent outbreaks, in winter 2016/2017, was investigated in this study. Clinical findings were in line with previous reports of IKC in semi-domesticated reindeer and the clinical signs displayed by the affected animals (n = 30) included increased lacrimation, follicular conjunctivitis, purulent secretions around the affected eyes and corneal edema. Laboratory analyses of the samples revealed the presence of Chlamydiaceae in most samples obtained from the clinically affected animals (98.3%, n = 60), but also a high seroprevalence of cervid herpesvirus 2 (CvHV2) antibodies (56.6%, n = 53). Moraxella bovoculi was isolated from nine IKC-affected animals during the outbreak (45.0%, n = 20). All affected animals were treated with long-acting antibiotics and recovered from the disease, testing negative for the presence of Chlamydiaceae DNA by PCR 16 days and 3 months after the initial treatment. For the first time, Chlamydia pecorum was identified in semi-domesticated reindeer, and the involvement of Chlamydiaceae in a clinical outbreak of IKC is reported. The CvHV2 seroprevalence (56.6%) and the data obtained from a previous outbreak in 2014 also suggest the involvement of the reindeer alphaherpesvirus in the recurrent outbreaks.

Mycoplasma conjunctivae in insect vectors and anatomic locations related to transmission and persistence

Mycoplasma conjunctivae is an obligate microparasite that causes Infectious Keratoconjunctivitis (IKC) in Caprinae species. IKC is a long-recognised disease, but little attention has been paid to the mechanisms of transmission of the mycoplasma and its occurrence in locations other than the eyes. In this study, the presence of M. conjunctivae is assessed in the eyes, external ear canals (EEC), nasal cavity, and vagina of host species as well as in potential vectors, which may be involved in the transmission and persistence of infection within the host.M. conjunctivae was detected by qPCR in 7.2 % (CI 95% 4.7-11.0) of the ear swabs and 9.5 % (CI 95% 6.4-13.9) of the nasal swabs from Pyrenean chamois, Iberian ibex, domestic sheep and mouflon without statistical differences between species. Mycoplasma detection in nasal swabs was mostly associated with ocular infection (95.6%), but this was not the case for EEC (52.6%). Among the eye-positive ruminants, 27.3% were positive in ear swabs and 64.7% in nasal swabs, and the threshold cycle values of the qPCR were correlated only between eye and nasal swabs (p < 0.01; r2 = 0.56). M. conjunctivae was detected in 1.7% - 7.1 % of Musca spp. captured during an IKC outbreak in Iberian ibex and in one out of three endemic sheep flocks.The results indicate that the transmission of M. conjunctivae may occur by direct contact with eye or nasal secretions and/or indirectly through flies. The M. conjunctivae DNA detection in EEC suggests that it can colonise the auditory tract, but the significance for its persistence within the host should be further assessed.

CASE REPORT: AN INFECTIOUS KERATOCONJUNCTIVITIS OUTBREAK CAUSED BYMYCOPLASMA CONJUNCTIVAEIN A DAIRY GOAT FARM

Although infectious keratoconjunctivitis (IKC) has occurred worldwide, no report has mentioned an IKC case in a dairy goat farm in an indoor management system. Moreover, few clinicians follow the IKC syndrome development throughout the clinical course. The aim of the present study was to report an IKC outbreak caused by Mycoplasma conjunctivae (MC) in indoor dairy goat barns. Severe IKC breakouts had been found consecutively in two nearby goat barns in a cooperated farm. To confirm the etiology, samples were collected from the infected goats to perform hematological, biochemical, bacterial examinations and polymerase chain reactions. A treatment of 4% boric acid and 0.5% povidone iodine solution, and a preventive spray of quaternary ammonium at 09:00 AM and 1% Virkon-S[Formula: see text] solution at 17:00 PM were useful to control disease in the adult goat barn, wherein 60% (31/55) animals showed different IKC signs. A total of 12 (14%) goat kids, died, without treatment, showed variable degrees of bronchointerstitial pneumonia. In all cases, only the DNA fragments of MC, but not other pathogens implicated in IKC, were detected. Goats began to recover after 30 days in an episodic duration of 81 days resulting in an estimated 240,000 New Taiwan dollars loss. In conclusion, this is the first goat MC report in an indoor system. The treatment and the preventive measure described in the current study were useful to control the event.

Postepizootic Persistence of Asymptomatic Mycoplasma conjunctivae Infection in Iberian Ibex.

The susceptibility of the Iberian ibex (Capra pyrenaica) to Mycoplasma conjunctivae ocular infection and the changes in their interaction over time were studied in terms of clinical outcome, molecular detection, and IgG immune response in a captive population that underwent a severe infectious keratoconjunctivitis (IKC) outbreak. Mycoplasma conjunctivae was detected in the Iberian ibex, coinciding with the IKC outbreak. Its prevalence had a decreasing trend in 2013 that was consistent with the clinical resolution (August, 35.4%; September, 8.7%; November, 4.3%). Infections without clinical outcome were, however, still detected in the last handling in November. Sequencing and cluster analyses of the M. conjunctivae strains found 1 year later in the ibex population confirmed the persistence of the same strain lineage that caused the IKC outbreak but with a high prevalence (75.3%) of mostly asymptomatic infections and with lower DNA load of M. conjunctivae in the eyes (mean quantitative PCR [qPCR] cycle threshold [CT ], 36.1 versus 20.3 in severe IKC). Significant age-related differences of M. conjunctivae prevalence were observed only under IKC epizootic conditions. No substantial effect of systemic IgG on M. conjunctivae DNA in the eye was evidenced with a linear mixed-models selection, which indicated that systemic IgG does not necessarily drive the resolution of M. conjunctivae infection and does not explain the epidemiological changes observed. The results show how both epidemiological scenarios, i.e., severe IKC outbreak and mostly asymptomatic infections, can consecutively occur by entailing mycoplasma persistence.IMPORTANCEMycoplasma infections are reported in a wide range of epidemiological scenarios that involve severe disease to asymptomatic infections. This study allows a better understanding of the transition between two different Mycoplasma conjunctivae epidemiological scenarios described in wild host populations and highlights the ability of M. conjunctivae to adapt, persist, and establish diverse interactions with its hosts. The proportion of asymptomatic and clinical M. conjunctivae infections in a host population may not be regarded only in response to intrinsic host species traits (i.e., susceptibility) but also to a specific host-pathogen interaction, which in turn influences the infection dynamics. Both epidemic infectious keratoconjunctivitis and a high prevalence of asymptomatic M. conjunctivae infections may occur in the same host population, depending on the circulation of M. conjunctivae, its maintenance, and the progression of the host-pathogen interactions.

Infectious keratoconjunctivitis in wild Caprinae: merging field observations and molecular analyses sheds light on factors shaping outbreak dynamics.

BackgroundInfectious keratoconjunctivitis (IKC) is an ocular infectious disease caused by Mycoplasma conjunctivae which affects small domestic and wild mountain ruminants. Domestic sheep maintain the pathogen but the detection of healthy carriers in wildlife has raised the question as to whether M. conjunctivae may also persist in the wild. Furthermore, the factors shaping the dynamics of IKC outbreaks in wildlife have remained largely unknown. The aims of this study were (1) to verify the etiological role of M. conjunctivae in IKC outbreaks recorded between 2002 and 2010 at four study sites in different regions of France (Pyrenees and Alps, samples from 159 Alpine ibex Capra ibex, Alpine chamois Rupicapra rupicapra and Pyrenean chamois Rupicapra pyrenaica); (2) to establish whether there existed any epidemiological links between the different regions through a cluster analysis of the detected strains (from 80 out of the 159 animals tested); (3) to explore selected pathogen, host and environmental factors potentially influencing the dynamics of IKC in wildlife, by joining results obtained by molecular analyses and by field observations (16,609 animal observations). All of the samples were tested for M. conjunctivae by qPCR, and cluster analysis was based on a highly variable part of the lppS gene.ResultsWe documented infections with M. conjunctivae in epidemic and endemic situations, both in symptomatic and asymptomatic animals. The identified M. conjunctivae strains were site-specific and persisted in the local wild population for at least 6 years. In epidemic situations, peaks of cases and disease resurgence were associated with the emergence of new similar strains in a given area. Social interactions, seasonal movements and the landscape structure such as natural and anthropogenic barriers influenced the spatio-temporal spread of IKC. Adults were more affected than young animals and host susceptibility differed depending on the involved strain.ConclusionOur study indicates that IKC is a multifactorial disease and that M. conjunctivae can persist in wildlife populations. The disease course in individual animals and populations is influenced by both host and mycoplasma characteristics, and the disease spread within and among populations is shaped by host behavior and landscape structure.Electronic supplementary materialThe online version of this article (doi:10.1186/s12917-017-0972-0) contains supplementary material, which is available to authorized users.

Molecular diagnosis of mycoplasma conjunctivae in an outbreak of infectious keratoconjunctivitis in sheep.

Summary Infectious keratoconjunctivitis (IKC) is a painful, highly contagious ocular disease in sheep and goats. This study was carried out for identification and characterization of causative agent of ocular disease in a sheep flock consisting of 300 ewes in Mashhad, Iran. Several ocular swabs were taken from affected animals. The samples were pooled and processed in a laboratory for isolation of suspecious agent. Following inoculation of the pooled sample in PPLO broth and agar, turbidity and growth of colonies were observed in them, respectively. Sequencing of the 1013 bp PCR product of 16S rDNA gene revealed that the causative agent of the outbreak has 100% sequence identity to Mycoplasma conjunctivae. Based on our knowledge this is the first documented report of isolation and molecular characterization of M. conjunctivae in Iran.

Dynamics of an Infectious Keratoconjunctivitis Outbreak by Mycoplasma conjunctivae on Pyrenean Chamois Rupicapra p. pyrenaica

Between 2006 and 2008, an outbreak of Infectious Keratoconjunctivitis (IKC) affected Pyrenean chamois Rupicapra p. pyrenaica, an endemic subspecies of mountain ungulate that lives in the Pyrenees. The study focused on 14 mountain massifs (180,000 ha) where the species’ population is stable. Cases of IKC were detected in ten of the massifs and, in five of them, mortality was substantial. The outbreak spread quickly from the first location detected, with two peaks in mortality that affected one (2007) and three (2008) massifs. In the latter, the peak was seasonal (spring to autumn) and, in the former, the outbreak persisted through winter. To identify the outbreak’s aetiology, we examined 105 Pyrenean chamois clinically affected with IKC. TaqMan rt-PCR identified Mycoplasma conjunctivae in 93 (88.5%) of the chamois. Another rt-PCR detected Chlamydophila spp. in 14 of chamois, and 12 of those had mixed infections with mycoplasmas. In the period 2000–2007, the chamois population increased slightly (λ 1.026) but decreased significantly during the IKC outbreak (λ 0.8, 2007–2008; λ 0.85, 2008–2009) before increasing significantly after the outbreak (λ 1.1, 2009–2010). Sex-biased mortality shifted the adult sex ratio toward males (from 0.6 to 0.7 males per female) and reduced productivity slightly. Hunting was practically banned in the massifs where chamois experienced significant mortality and allowed again after the outbreak ended. Long-term monitoring of wild populations provides a basis for understanding the impacts of disease outbreaks and improves management decisions, particularly when species are subject to extractive exploitation.

OCCURRENCE, QUANTIFICATION, AND GENOTYPING OF MYCOPLASMA CONJUNCTIVAE IN WILD CAPRINAE WITH AND WITHOUT INFECTIOUS KERATOCONJUNCTIVITIS

Mycoplasma conjunctivae, the causative agent of infectious keratoconjunctivitis (IKC), was recently detected in asymptomatic Alpine ibex (Capra ibex ibex). This suggested that an external source of infection may not be required for an IKC outbreak in wildlife but might be initiated by healthy carriers, which contradicted previous serologic investigations in chamois. Our aims were to 1) assess the prevalence of M. conjunctivae among asymptomatic ibex and Alpine chamois (Rupicapra rupicapra rupicapra) and its frequency in IKC-affected animals, 2) determine mycoplasma loads in different disease stages, and 3) characterize the M. conjunctivae strains involved. Eye swabs from 654 asymptomatic and 204 symptomatic animals were collected in diverse Swiss regions between 2008 and 2010, and tested by TaqMan real-time PCR. Data analysis was performed considering various patterns of IKC occurrence in the respective sampling regions. Strains from 24 animals were compared by cluster analysis. Prevalence of M. conjunctivae was 5.6% (95% confidence interval [CI]: 3.7-8.1%) in asymptomatic ibex and 5.8% (CI: 3.0-9.9%) in asymptomatic chamois, with significant differences between years and regions in both species. Detection frequency in symptomatic animals was significantly higher during IKC outbreaks than in nonepidemic situations (i.e., regular but low incidence or sporadic occurrence). Mycoplasma load was significantly lower in eyes from healthy carriers and animals with mild signs than from animals with moderate and severe signs. Although some strains were found in both asymptomatic and diseased animals of the same species, others apparently differed in their pathogenic potential depending on the infected species. Overall, we found a widespread occurrence of M. conjunctivae in wild Caprinae with and without IKC signs. Our results confirm the central role of M. conjunctivae in outbreaks but suggest that other infectious agents may be involved in IKC cases in nonepidemic situations. Additionally, presence and severity of signs are related to the quantity of M. conjunctivae in the eyes rather than to the strain. We propose that individual or environmental factors influence the clinical expression of the disease and that persistence of M. conjunctivae in populations of wild Caprinae cannot be excluded.

Outbreaks of infectious keratoconjunctivitis in alpine chamois and ibex in Switzerland between 2001 and 2003

Five outbreaks of infectious keratoconjunctivitis (IKC) affecting alpine chamois and ibex in the western and central Swiss Alps were recorded in 2001 to 2003. Mycoplasma conjunctivae was identified from conjunctival...

Infectious keratoconjunctivitis of ibex, chamois and other Caprinae.

Infectious keratoconjunctivitis (IKC) caused by Mycoplasma conjunctivae is a highly contagious ocular infection which is common in domestic sheep and goats. In the European Alps, IKC is often observed in Alpine chamois (Rupicapra r. rupicapra) and in Alpine ibex (Capra i. ibex), but the disease has also been described in other wild Caprinae in the Pyrenees and in New Zealand. The infection is characterised by inflammation of the conjunctiva and cornea, and in the most advanced stages, the cornea is opaque or even perforated. In IKC outbreaks in chamois and ibex, spontaneous recovery is the most prevalent outcome of the disease. However, mortality can occasionally reach 30%. Recent studies in eastern Switzerland indicated that M. conjunctivae infection is not self-maintained in chamois. In contrast, the disease is endemic and self-maintained in the domestic sheep population. Spillover of the agent from sheep living in proximity during summer may be the origin of point-source epidemics in wild Caprinae. Flies are likely to play a central role in interspecific transmission of M. conjunctivae on alpine meadows. When outbreaks of IKC occur in wildlife, a special effort should be made to avoid unnecessary human disturbance in affected areas. However, animals presenting irreversible ocular lesions should be shot by professional gamekeepers to prevent suffering. Prevention of IKC in wild Caprinae should focus on preventing the spillover of M. conjunctivae from livestock. However, studies are required to evaluate the distribution of M. conjunctivae infection in domestic sheep in several countries and to assess the risk of IKC spillover from domestic animals to wildlife. In addition, immunological studies should be performed to develop tools which could lead to the control of M. conjunctivae infection in domestic sheep.

Mycoplasma conjunctivae infection is not maintained in alpine chamois in eastern Switzerland.

The occurrence of infectious keratoconjunctivitis (IKC) was assessed in alpine chamois (Rupicapra rupicapra rupicapra) in Grisons (Switzerland) from 1950 to 1999. The first IKC outbreaks were reported in the 1950's. Since then, the number of affected subpopulations constantly increased and, by 1999, IKC outbreaks were reported in 39 of 51 (77%) chamois sub-populations. From 1992-99, a total of 243 chamois which died of the consequences of IKC were recorded. The number of cases differed between years, and a distinct seasonal trend was observed. Infectious keratoconjunctivitis was more common during summer and autumn, with 48% of the cases recorded in August-October. Juveniles (< 4 yr of age) were mostly represented. To verify the presence of Mycoplasma conjunctivae in chamois we analyzed conjunctival swabs taken from animals affected with IKC. Among a sample of 28 affected chamois, M. conjunctivae was identified 14 times (50%). An indirect enzyme-linked immunosorbent assay (ELISA) was developed to detect specific M. conjunctivae antibodies in sera of alpine chamois with IKC. We performed a serologic investigation to assess whether M. conjunctivae infection is self-maintained in the chamois population in Grisons. In subpopulations with IKC oubreaks, seroprevalence was low (8%). Seroprevalence was even lower in subpopulations with recent IKC outbreaks (3%). We concluded that the M. conjunctivae infection is not self-maintained in alpine chamois in Grisons. The agent may originate in domestic sheep living in proximity to chamois during summer. Control of IKC in chamois should consider immunoprophylaxis in sheep or limiting interspecific transmission of M. conjunctivae.

Cross-sectional study of the clinical and microbiological status of eyes of sheep during an infectious keratoconjunctivitis outbreak.

Cross-sectional study of the clinical and microbiological status of eyes of sheep during an infectious keratoconjunctivitis outbreak.

Outbreak of ovine infectious kerato-conjunctivitis caused by Mycoplasma conjuctivae

An outbreak of infectious kerato-conjunctivitis in 25 adult ewes is reported. Mycoplasma conjunctivae was frequently isolated from most eyes prior to treatment. Although treatment was effective in regressing the clinical signs of the disease, there was continued and increased isolation of M. conjunctivae in all eyes (50) treated for 6 days on days 14, 44 and 74 following treatment. It is suggested that the carrier animals and contact between sheep were responsible for the spread of infection with M. conjunctivae. The antibody response assayed by the Metabolism Inhibition test (MIT) showed an increase in geometric mean titre (GMT) from 51 on day 0 (first day of treatment) to 72 on day 7 after treatment and fell to 24 by day 74. The persistence and difficulty of eliminating M. conjunctivae from affected eyes after treatment is discussed.