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Mycoplasma conjunctivae is the etiological agent of infectious keratoconjunctivitis, a highly contagious ocular infection that affects both domestic and wild Caprinae species in the European Alps. In order to study the transmission and spread of M. conjunctivae across domestic and wild Caprinae populations, we developed a molecular method for subtyping and identifying strains of M. conjunctivae. This method is based on DNA sequence determination of a variable domain within the gene lppS, a gene that encodes an antigenic lipoprotein of M. conjunctivae. This domain of lppS shows variations among different strains but remains constant upon generations of individual strains on growth medium and thus allows identification of individual strains and estimation of their phylogenetic intercorrelations. The variable domain of lppS is amplified by PCR using primers that match conserved sequences of lppS flanking it. Sequence analysis of the amplified fragment enables fine subtyping of M. conjunctivae strains. The method is applicable both to isolated strains and to clinical samples directly without requiring the cultivation of the strain. Using this method, we show that M. conjunctivae was transmitted between domestic and wild animals that were grazing in proximate pastures. Certain animals also presented infections with two different strains simultaneously.

In order to study horizontal transmission of Mycoplasma synoviae an avian pathogen, a reverse transcription-polymerase chain reaction (RT-PCR) assay was developed to detect viable Mycoplasma in environment. The test was based on the RT-PCR of the 16S ribosomal RNA (rRNA) of Mycoplasma genus. Results showed that Mycoplasma 16S rRNA was stable up to 23 h after cell death. Therefore, the test allowed detection of viable or very recently (less than 23 h) dead mycoplasmas. M. synoviae survival in artificially contaminated water, food and soil and in the environment of M. synoviae experimentally infected turkeys was estimated by culture and RT-PCR. The RT-PCR method was then applied in a naturally infected laying hen farm showing problems of recurrent mycoplasmosis in the hens. Results confirmed the usefulness of RT-PCR in checking the efficiency of biosecurity measures and in improving cleaning and disinfection protocols.

The polymerase chain reaction (PCR) was used to detect Mycoplasma gallisepticum in samples collected from the environment of experimentally or naturally infected poultry. Culture was also used in the experimental infections. Of 160 samples of food, drinking water, feathers, droppings or dust collected during experimental infection, 103 were positive using a M. gallisepticum-specific PCR (MG-PCR) and 68 were positive using a PCR (mycoplasma-PCR) that detects all species of the genera Mycoplasma, Spiroplasma, Acholeplasma and Ureaplasma. Six of these samples were also positive by culture. In environmental samples collected on a depopulated M. gallisepticum-positive turkey farm, three and two out of a total of 12 were positive by mycoplasma-PCR and MG-PCR, respectively. These results indicate the disseminating capacity of this mycoplasma and the possible use of PCR methods for epidemiological analyses and control of farm decontamination before the introduction of new birds.

The aim of this study was to establish whether enzootic pneumonia could be induced reliably in piglets by administering an aerosolised culture of Mycoplasma hyopneumoniae. Groups of five M hyopneumoniaefree Landrace x Large White piglets weaned at 11 to 14 days of age were exposed to aerosols of in vitro cultures of a virulent strain of M hyopneumoniae. In three separate trials, 14 of 15 pigs exposed to the bacteria developed pneumonia, but pigs exposed to the culture medium alone did not develop the disease. Lung pathology, both gross and histological, indicated acute disease. Ten of the pigs were tested for seroconversion by Western blot and they were all positive. The growth rates of the infected pigs were significantly reduced and the water consumption of the infected groups was also depressed. M hyopneumoniae was recovered from eight of the 15 infected pigs.

Objective: To explore the hypothesis of pathogenic relationship between urogenital mycoplasma infection and adverse perinatal outcomes., Methods: Four hundred and eighty-eight mycoplasma-positive pregnant women detected by culture method were randomly divided into erythromycine-intervention group and non-intervention group. Comparison was made on rate of reverse sero-conversion, of vertical transmission to mycoplasma and adverse perinatal outcomes incidence between groups., Results: Ureaplasma urealyticum sero-conversion rate and rate of vertical-transmission in intervention group were significantly lower than in non-intervention group (P < 0.05). The incidences rates of preturm labor, post partum fever, puerperal infection and neonate pneumonia in intervention group were significantly lower than in non-intervention group (P < 0.05)., Conclusion: Erythromycin is effective in control of ureaplasma urealyticum infection among pregnant women through cutting off vertical transmission passway and lowering adverse perinatal outcomes against ureaplasma urealyticum.

Since 1994, an epidemic of conjunctivitis caused by Mycoplasma gallisepticum (MG) has spread throughout the eastern population of house finches (Carpodacus mexicanus). The adaptation of MG to a free-flying avian species presents potential problems for the control of mycoplasmosis in commercial poultry. To evaluate risks associated with this emerging problem, a field survey was conducted to assess prevalence of MG infection in house finches and other passerine birds associated with poultry farms. Between November 1997 and March 1999, 1058 birds were captured by mist net or trap at 17 farms and at 10 feeder stations in northeast Georgia. Birds were bled and screened by serum plate agglutination (SPA) for antibodies to MG. Birds with negative or weak positive SPA results were released at capture sites, and those with strong positive SPA reactions were kept for further evaluation. Necropsies were performed on selected house finches and individuals of 11 other passerine species, and samples were collected for MG testing by culture, polymerase chain reaction (PCR), hemagglutination inhibition, and histopathology. Testing revealed 19.1% of 671 birds caught at farms and 11.6% of 387 birds caught at feeder sites were SPA positive for MG. Three house finches captured on farms were positive for MG by culture and PCR, whereas three from feeder sites were positive only by PCR. No MG isolates were made from tufted titmice (Baeolophus bicolor), but 40% were positive by PCR. Individuals from 10 additional species were SPA positive only. Results suggest that MG persists at low levels in house finches in northeast Georgia and that tufted titmice may be nonclinical carriers of MG or a related mycoplasma. Positive SPA reactions in other species may be caused by nonspecific reactions or contact exposure. Current biosecurity recommendations should be sufficient to minimize risks of transmission between wild and domestic birds.

We recently reported that most Trichomonas vaginalis isolates cultured in vitro are infected by Mycoplasma hominis. In this work, we have characterized some aspects of the relationships between the two microorganisms. PCR, cultivation, and immunological methods revealed that the number of M. hominis organisms carried by T. vaginalis in culture varied from isolate to isolate, suggesting a specific multiplicity of infection. Moreover, infected T. vaginalis isolates were able to pass bacteria not only to M. hominis-free protozoa, but also to human-derived epithelial cells. The in vitro transmission of the bacterium from T. vaginalis to both uninfected parasite isolates and human epithelial cells suggests a role for T. vaginalis as a carrier of the M. hominis infection in vivo.

An epidemiological study of the prevalence of mycoplasmal conjunctivitis in the house finch (Carpodacus mexicanus) was conducted in Auburn (Alabama, USA) between March 1998 and February 1999. Clinical disease was observed in 4% of the 1,214 finches trapped and examined. This rate is comparable to the average annual prevalence observed in this population since 1996, although the prevalence of clinical disease observed in the peak months of September through November was lower than in previous years. Clinically ill birds were observed in all months of the study. To estimate the prevalence of recovering and asymptomatic, infected birds, we tested a subset of 334 house finches serologically for exposure to Mycoplasma gallisepticum (MG) using the serum plate agglutination (SPA) assay. The prevalence of clinical disease in this subsample was slightly higher (7%) than in the entire sample, reflecting the fact that the serological survey was initiated in the late summer when the prevalence of MG infection peaks in our study population and a sampling bias for symptomatic birds. The serological survey indicated that 13% of this subpopulation had been exposed to MG. We also tested 46 of 334 finches by polymerase chain reaction (PCR) to detect MG in seropositive, asymptomatic birds. Use of the PCR in conjunction with the SPA detected six asymptomatic, infected birds that may represent potential carriers or birds in the early stages of infection. The decreasing prevalence of clinical disease observed during the peak months suggests a changing host-parasite relationship. Continued surveillance of this population, employing both clinical observation and serological analysis will be useful in characterizing these changes over time.

An epidemic of conjunctivitis among house finches (Carpodacus mexicanus) caused by Mycoplasma gallisepticum (MG) bacterial infections was first described in 1994. The disease exhibits high primary host specificity, but has been isolated from a limited number of secondary avian hosts at various times and locations. We used records from the House Finch Disease Survey, a continent-wide, volunteer monitoring project, to document the host range of conjunctivitis in birds at feeding stations and to investigate how disease in house finches might influence the spread of conjunctivitis to other hosts. Between 1994 and 1998, participants recorded 675 cases of conjunctivitis in 31 species other than house finches in eastern North America. Seventy five % of these cases were observed among three species: American goldfinches (Carduelis tristis), purple finches (Carpodacus purpureus) and house sparrows (Passer domesticus). The proportion of sites with diseased wintering populations of the three species increased over the 4 yr study and coincided with range expansion of conjunctivitis in house finches. Sites with diseased house finches present were significantly more likely to report conjunctivitis in each of the three species during the same month. These observations are most consistent with transmission of an infectious agent (presumably MG) from house finches to these secondary hosts via spillover of localized epidemics, rather than sustained interspecific transmission.

A comparison of infection and immunity to Mycoplasma gallisepticum (MG) in broiler chicken breeders vaccinated with a temperature-sensitive mutant of MG versus nonvaccinated chickens, and the impact on the performance of their offspring was conducted. Infection and immunity in breeders were assessed by culture and enzyme-linked immunoassay, respectively. However, performance in their offspring was assessed by studying MG infection in embryos, occurrence of infection titers to MG in relation to mortality, and feed conversion in the broilers. Five out of 10 broiler chicken breeder flocks raised on the same multiple-age farm with a long history of mycoplasmosis were vaccinated intraocularly once with a temperature-sensitive MG mutant vaccine (ts-11) at an average age of 7.5 wk; another five breeder flocks were left as unvaccinated controls exposed to field MG. The average recoveries of ts-11 organisms from tracheas and infraorbital sinuses of 41-wk-old vaccinates were 88 and 84%, respectively. No field MG organisms were recovered from vaccinates between 15 and 41 wk of age. The recovery of field MG organisms from tracheas and sinuses of nonvaccinated chickens increased to an average of 100% at 41 wk of age. A significant decrease (P < 0.05) in the average percentage of MG-seroconverted breeders occurred in ts-11-vaccinated flocks in comparison with nonvaccinated, MG-infected flocks at 15, 20, 23, 29, 32, 36, and 41 wk of age. The average infection prevalence by MG in the vitelline membrane of 7-d-old embryos produced by the five unvaccinated breeder flocks peaked at 79% when their respective hatching eggs were collected at 36 wk of breeder's age. Embryos of ts-11-vaccinated flocks had zero prevalence of MG infection at all times between 29 and 57 wk of breeder's age. Seroconversion to MG (average of 17.7%) at 42 d of age was only present in sera of 10 offspring broiler flocks of the nonvaccinated breeders. However, a lack of seroconversion to MG occurred in 10, 42-d-old offspring broiler flocks of the five ts-11-vaccinated breeder flocks. This lack was associated with a lower, better average feed-conversion ratio (2.05) (P < 0.05) and a lower average mortality percentage (5.3%) (P < 0.05) in comparison with those obtained in the offspring of the five unvaccinated, MG-infected breeder flocks. The results indicate that vaccination of broiler chicken breeders with a temperature-sensitive mutant of MG prevented infection by field MG in tracheas and infraorbital sinuses of these breeders and in the vitelline membranes of their embryos. In addition, the broiler offspring of the vaccinated breeders had a better production performance.

Eperythrozoon is an obligate parasitic bacteria found in many species of animals. A large scale investigation of the prevalence of Eperythrozoon spp. in humans, was conducted in a developing country using light, electron microscope and animal inoculation. Samples were collected in undeveloped areas of Inner Mongolia in China over a 2-year period of 1994-6. Of the 1529 investigated samples, 35.3% were found to be Eperythrozoon spp. positive. The prevalence of infection was associated with occupation and seasonal variations. The infections were mainly mild, in 89.6% of cases (excluding pregnant women and their children). Of 74 pregnant women tested in the areas of high prevalence, 44 were confirmed Eperythrozoon spp. positive. Similarly, eperythrozoa were found in all 44 umbilical cords tested and in the neonatal peripheral blood samples taken at birth. These data suggest that eperythrozoa can be transmitted via the placenta.

Nine of 74 American alligators (Alligator mississippiensis) from a captive Florida herd of 3-4-m-long, 200-350-kg, adult males greater than 30 yr of age died within a 10-day period during 1995. Nonspecific clinical signs included anorexia, lethargy, muscle weakness, paraparesis, bilateral white ocular discharge, and various degrees of periocular, facial, cervical, and limb edema. Pneumonia, pericarditis, and arthritis were found on postmortem evaluation of the spontaneously dead and euthanatized alligators. Rapidly growing mycoplasmas were identified by culture, and mycoplasma nucleotide sequences were identified by polymerase chain reaction testing of fresh lung and synovial fluid from an affected alligator. Culture of banked frozen lung from necropsy specimens and fresh lung and fresh synovial fluid from newly affected alligators confirmed the presence of a new mycoplasma species in seven of eight individuals. Oxytetracycline was administered, but related deaths continued for 6 mo until only 14 of the initial alligators remained. An enzyme-linked immunosorbent assay to detect antibody was developed, and the organism was transmitted experimentally to naive juvenile alligators, although the source of the organism, Mycoplasma sp. (ATCC 700619), has not been identified. The alligator isolate is a novel species in the mycoplasma family because its nucleotide sequence does not match those of over 75 characterized mycoplasma species. Such factors as population density, animal age, and mycoplasmal virulence likely contributed to the course of disease.

Our objectives were to study the distribution of Chlamydia trachomatis and Mycoplasma genitalium in men with or without non-gonococcal urethritis (NGU) and their respective female partners. A case-control study was carried out to which men with or without NGU and their female partners were recruited. All study participants were tested for the presence of C. trachomatis and M. genitalium. An analysis firstly of the distribution of each of these microorganisms among men with or without urethritis and their respective female partners was carried out. Furthermore, we examined the association of each of these microorganisms and NGU when the other had been excluded. Chlamydia trachomatis was present in 14 (36%) of 39 men with NGU compared to none of 12 men without NGU (P=0.022). The prevalence rates for female partners of men with NGU were 10 (26%) of 39 compared to none of 12 partners of men without NGU (P=0.092). M. genitalium was detected in 12 (33%) of 36 men with NGU compared to 1 (9%) of men without NGU (not significant; P=0.147). The prevalence rates for female partners of men with NGU were 10 (32%) of 31 women compared to none of 7 partners of men without NGU (not significant; P=0.156). There was a greater concordance than discordance of carriage of each of the 2 microorganisms among the study couples and each tended to be carried independently of the other by men. Analysis of the association between the presence of C. trachomatis in men and NGU was significantly improved by the exclusion of men with M. genitalium (P=0.0058). Likewise, the association between the presence of M. genitalium in men and NGU was significantly improved by the exclusion of couples in whom either the man or woman was C. trachomatis-positive (P=0.049). The independent carriage of C. trachomatis and M. genitalium by men with NGU, coupled with the improved association between each pathogen and NGU by exclusion of the other provides support for the separate role of each in the aetiology of NGU.

Successful detection of Mycoplasma synoviae (MS) by culture and PCR from samples collected in the environment of experimentally infected chickens and turkeys, or under field conditions, is described. Results showed that in the experimental infection, 10/96 and 46/96 samples of food, drinking water, feathers, droppings or dust were positive by culture and Mycoplasma-PCR. In field conditions, the number of positive results for environmental samples were respectively 7/28 and 17/28. These observations highlight the high disseminating capacities of this mycoplasma and show the usefulness of the PCR method for epidemiological studies.

Although many new diseases have emerged within the past 2 decades [Cohen, M. L. (1998) Brit. Med. Bull. 54, 523-532], attributing low numbers of animal hosts to the existence of even a new pathogen is problematic. This is because very rarely does one have data on host abundance before and after the epizootic as well as detailed descriptions of pathogen prevalence [Dobson, A. P. & Hudson, P. J. (1985) in Ecology of Infectious Diseases in Natural Populations, eds. Grenfell, B. T. & Dobson, A. P. (Cambridge Univ. Press, Cambridge, U.K.), pp. 52-89]. Month by month we tracked the spread of the epizootic of an apparently novel strain of a widespread poultry pathogen, Mycoplasma gallisepticum, through a previously unknown host, the house finch, whose abundance has been monitored over past decades. Here we are able to demonstrate a causal relationship between high disease prevalence and declining house finch abundance throughout the eastern half of North America because the epizootic reached different parts of the house finch range at different times. Three years after the epizootic arrived, house finch abundance stabilized at similar levels, although house finch abundance had been high and stable in some areas but low and rapidly increasing in others. This result, not previously documented in wild populations, is as expected from theory if transmission of the disease was density dependent.

Mycoplasma gallisepticum (MG) has been isolated from wild house finches. The pathogenic effects of MG finch strain (K4058) and MG R-strain were compared after exposure of chickens and turkeys. Gross and histologic lesions, reisolation of the organism, serology, and clinical disease were evaluated. Milder histologic and gross lesions, in addition to lower serologic titers, occurred in birds inoculated with the finch strain. Mortality, concurrent with clinical and gross respiratory signs and lesions, was observed only in chickens challenged with R-strain. Both the MG finch strain and MG R-strain were recovered from the respective challenge groups at 14 and 28 days postexposure. The results show that MG isolated from wild house finches may infect domestic poultry species but causes only mild disease and is less virulent than MG R-strain. Commercial enzyme-linked immunosorbent assay kits best detected the serologic response of chickens and turkeys to the MG finch strain.

Objective: To determine the spread of respiratory infection with Mycoplasma pneumoniae in an institute for mentally disabled persons., Design: Descriptive., Methods: In the period from mid-April to mid-September in a certain year the transmission of M. pneumoniae in the facility was evaluated using questionnaires and laboratory investigations. The laboratory investigations consisted of an M. pneumoniae specific polymerase chain reaction (PCR) on throat swab specimens and detection of antibodies in serum., Results: 21 Residents and 26 staff members from 2/36 units were involved in the initial investigation. 17 Persons had complaints of a (recent) respiratory infection (cough, malaise and fever). In 9 cases an M. pneumoniae infection was confirmed, in 5 cases by PCR and in 4 cases by serology. Two PCR positive persons had only complaints of coughing. During the investigation period 2 more persons were diagnosed with a respiratory infection due to M. pneumoniae. No new cases were found by investigation of contacts outside the facility., Conclusion: M. pneumoniae can cause an outbreak of M. pneumoniae respiratory infection in an institute for mentally disabled persons. Rapid detection of this pathogen is possible by PCR and is important for proper antibiotic therapy and epidemic-control measures.

The presence of Ureaplasma urealyticum, Mycoplasma hominis, and Chlamydia trachomatis was explored in 50 public restroom toilet bowls. We used culture, antigen detection, polymerase chain reaction, and survival assay. Five bowls (10%) were contaminated with at least one organism. U. urealyticum was found in four bowls, M. hominis in three, and C. trachomatis in one. U. urealyticum survived on the toilet rim for up to 2 hours.

The etiologic agent of seal finger (speck finger) is unknown. Seal finger occurs after a seal bite, and the symptoms include acute pain, swelling, discharge, and, in some cases, there is joint involvement. The discovery of Mycoplasma species in epidemics of seal disease prompted attempts to link seal finger to mycoplasma. Mycoplasma species were isolated in cultures of a specimen from the finger of an aquarium trainer who was bitten by a seal and of a specimen from the front teeth of the biting seal. The two Mycoplasma isolates were identical biochemically; they were serum-dependent and hydrolyzed arginine. The isolates were susceptible to tetracycline but resistant to erythromycin. By growth inhibition and immunofluorescent antibody tests, both strains were identified as Mycoplasma phocacerebrale, a mycoplasma isolated in an epidemic of seal disease occurring in the Baltic Sea. The patient's infection was treated successfully with tetracycline. To our knowledge, this is the first case in which a mycoplasma has been associated with seal finger.

Ureaplasma urealyticum and Mycoplasma hominis, two genital mycoplasmas, are the most common organisms isolated in the perinatal period and both either cause or are associated with poor perinatal outcomes. We speculate that these microbes could increase inflammation by stimulating macrophages to produce tumor necrosis factor-alpha (TNF-alpha) and inducible nitric oxide synthase because of their propensity to interact with the host's immune system. To test this hypothesis, RAW 264.7 cells, a murine macrophage cell line, were coincubated for 16 h with either U. urealyticum or M. hominis, and LPS and sterile broth were used as controls. Lipopolysaccharide (LPS) and both mycoplasmas induced TNF-alpha production, which was concentration-dependent, whereas sterile broth had little effect. TNF-alpha production was not inhibited by the addition of polymyxin B, excluding the possibility of contaminating endotoxin in this effect. Inducible nitric oxide synthase was produced only in the presence of recombinant inteferon-gamma. We conclude that both viable and nonviable U. urealyticum and M. hominis are capable of TNF-alpha induction from murine macrophages and that LPS is not involved in this event. Also, the genital mycoplasmas are capable of stimulating inducible nitric oxide synthase production from murine macrophages. We speculate that the genital mycoplasmas produce perinatal disease by producing proinflammatory mediators by their interaction with inflammatory cells and either induce or act as a catalyst and augment inflammation which in turn leads to a poor pregnancy outcome.

Background: A prospective study was carried out at the University Hospital, Kuala Lumpur to determine the cervical carriage rate of Ureaplasma urealyticum and Mycoplasma hominis among healthy pregnant women at delivery and the incidence of nasopharyngeal colonisation among their infants., Patients: Sixty mother and baby pairs were examined., Results: Cervical colonisation among the mothers was found to be 56.7% for U.urealyticum and 17.7% for M.hominis. The transmission rate to their infants was 88.2% and 30% for U.urealyticum and M.hominis respectively., Conclusion: There was no statistically significant difference in the maternal colonisation rates according to ethnic group, parity and past history of abortion. All U.urealyticum isolates in our study were sensitive to erythromycin but about one-third were resistant to tetracycline and ciprofloxacin and 26.5% were resistant to minocycline.

Although Mycoplasma gallisepticum (MG) is established in house finch (Carpodacus mexicanus) populations in at least 33 states, the potential risk of MG introduction to domestic poultry by infected finches currently is unknown. The objectives of this study were to determine if chickens could be infected with the finch strain of MG via direct, across-wire, and proximity (across-room) contact with naturally infected house finches and to determine if house finches could be infected through direct contact with experimentally infected chickens. Chickens were infected with the finch strain of MG through direct contact with naturally infected house finches, a determined by seroconversion (80%), polymerase chain reaction (PCR) (20%), and culture of MG (30%). Clinical disease was not observed in infected chickens. Isolates from chickens were identified as the original finch strain by arbitrary primed PCR. Transmission required an extended period of direct contact (10 wk) with infected finches, and no evidence of MG infection was detected in chickens exposed to infected finches across wire or across the room. Evidence of contact transmission of MG from infected chickens to house finches was limited to positive serum plate agglutination results, and infection could not be confirmed by PCR or culture. Results suggest that minimal biosecurity measures that restrict direct contact between chickens and house finches should significantly reduce the potential for MG transmission between these species.

Fifteen mycoplasma-free chickens were contact exposed to five chickens that had been experimentally infected with one of three different strains (two field strains and one laboratory strain) of Mycoplasma synoviae (MS). Culture and polymerase chain reaction (PCR) were positive by 3 days postinoculation (PI) in the experimentally infected birds. Lateral transmission was found by 7-14 days postexposure. Positive serum plate agglutination (SPA) results were detected 3-4 wk after positive culture and/or PCR in individual birds. By 42 days PI, all the birds in the groups exposed to field strain K1858 or K3344 had become infected as determined by culture and PCR, whereas only half of the birds in the group exposed to laboratory strain WUV1853 had become infected. Because of the unanticipated lack of seroconversion to hemagglutination inhibition (HI) and enzyme-linked immunosorbent assay (ELISA) in infected chickens, the study was extended. Each group was split into two groups of 10 birds each, one of which was vaccinated with a live B1/LaSota Newcastle disease (ND) vaccine virus to determine if a viral respiratory challenge might incite a stronger antibody response to the mycoplasma infection. All the birds were tested for seroconversion 14 and 21 days later. Of the birds vaccinated for ND, a slightly greater number were MS positive by SPA than the nonvaccinated birds. This effect was not present 21 days after vaccination, and there was no significant difference in the MS HI results from these groups, suggesting that the viral respiratory infection had little direct impact on seroconversion. The virulent field strain (K3344) elicited a stronger MS antibody response than the other strains. All results from the MS ELISA were negative in all groups through 9 wk. Positive results from PCR analysis correlated well with culture results, whereas serologic tests did not detect MS infection for several weeks. Monitoring programs solely dependent on seroconversion may be inadequate for diagnosis and control of mycoplasma infections.

A clinical, bacteriological, serological and patho-anatomical study was carried out on 12 goats surviving the acute stage of contagious caprine pleuropneumonia (CCPP), experimentally produced with Mycoplasma capricolum ssp. capripneumoniae (M. capripneumoniae), with the major aims of investigating the chronic stage of the disease and elucidating the possibility of a carrier state beyond the acute fulminant phase. The goats were killed 9, 16, 82 or 126 days after the onset of acute clinical signs. On day 9, clinical signs included low grade fever and persistent coughing. Thereafter, only intermittent coughing was recorded. Serum titres of complement-fixing antibodies to M. capripneumoniae were high at the period of fever but dropped thereafter. Post-mortem examination showed acute fibrinous pleuropneumonia on days 9 and 16, and chronic pleuropneumonia on days 82 and 126, including sequester formations in goats killed on day 126. Mycoplasma capripneumoniae was isolated on days 9 and 16 but not on later occasions. The study showed that goats recovered from acute CCPP may have lesions for a long time thereafter but provide no evidence of a carrier state among long-term survivors.

Specific pathogen free hens and males were experimentally infected with Mycoplasma gallisepticum. Eggs were then collected, and a part was incubated and set for hatching. Mycoplasma cultures were performed on infected adults and antibodies to MG were analysed by use of slide agglutination (SA) test and commercial ELISA tests on adults and chicks sera and on yolks from non incubated eggs. Both ELISA tests could detect antibodies in yolks from non incubated eggs laid three weeks after infection. SA and the three ELISA tests revealed positive sera in chicks hatched from eggs laid as soon as one week after infection.

The correlation between climatic parameters with one another in fattening units and the influence of environmental factors on lung lesions registered at slaughter were studied in 6 integrated herds with continuous production systems. In addition, the influence of environmental parameters on the spread of Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae (serotypes 2 and 3) and on the productivity was monitored in 2 specialized fattening herds with strict batch production. The outdoor temperature was positively correlated to the indoor temperature, but negatively correlated to the relative humidity and the concentration of carbon dioxide in the stables. These indoor parameters were also correlated to each other. The concentration of ammonia was not correlated to any other climatic parameter. No correlation between the climatic parameters measured and the prevalences of pneumonia and pleuritis registered at slaughter was shown. The rapidness in spread of mycoplasmosis seemed to be more dependent of the antibody status of the pigs on arrival than on the climate of the units. In contrast, a correlation between the climatic parameters and the spread of the less contagious infection (Actinobacillus) was indicated. The influence of the climatic parameters on the daily weight gain was not ensured.

Since zoonoses (singular zoonosis) are infections or infectious diseases of animals transmissible to man, or occasionally from man to other animal species, it is logical that should any diseases of plants be found that are transmissible between plants and man they should be termed phytonoses (singular phytonosis). The genome of human uveitis mycoplasma-like organisms (MLO) has been reported to be showing a very high homology to plant MLO. For this reason, and because there are several other known similarities between plant and human MLO, it is hypothesized that at least one class of phytonoses, namely cross-infection of MLO between plants and man, exists. There are, however, other possibilities. Cross-infection transmission experiments, the results of which could add credibility to the hypothesis, could be undertaken.

A flock of sheep consisting of 60-70 winterfed ewes was examined. Blood was collected from approximately 30% of the sheep four times from 1991 to 1995. Eperythrozoon ovis (Ep. ovis) organisms were not detected in blood smears stained with Wright's stain in 1991 and 1993. In 1995, examination of blood smears stained with acridine orange revealed Ep. ovis organisms in 11 of 26 sheep, whereas examination of smears stained with Wright's stain revealed organisms in only one ewe with a high degree of infection. The prevalence of antibodies detected by IFAT varied from 58-100%. The antibody titres varied from 1:20 to 1:12,000. This investigation indicates that Ep. ovis infection once present in a flock of sheep may spread easily among the sheep, and that the infection seems to persist within the flock.

Haemoparasitic diseases have long been considered as a major problem to efficient sheep and goats production in Iran. Theileriosis due to Theileria hirci and babesiosis due to Babesia ovis and B. motasi are the most pathogenic protozoa. B. crassa, Anaplasma ovis and Eperythrozoon ovis are usually non-pathogenic and do not cause any apparent problem. The major tick genera found on sheep and goats are Hyalomma, Rhipicephalus, Haemaphysalis, Ixodes and rarely Dermacentor distributed in all part of Iran. Our studies indicate that only Hyalomma ticks transmit Theileria species but the others transmit Babesia, Anaplasma and Eperythrozoon. The two latter ones can also be transmitted through some biting flies and mechanical means. Control methods presently available in Iran rely almost entirely on: (i) vaccination of sheep and goats with cell culture vaccine for theileriosis; (ii) chemotherapeutic treatment for babesiosis and anaplasmosis; (iii) acaricides for control of tick vectors.

In separate trials, layer pullets were vaccinated with Mycoplasma gallisepticum (MG) strain 6/85 or strain ts-11 commercially produced live vaccines. For a 15-wk postvaccination (PV) period, vaccinates were commingled with unvaccinated pullets and were in indirect contact with sentinel groups of pullets, broiler breeders, turkey breeders, or meat turkeys in adjoining pens. Infectivity and transmissibility of vaccine strains were determined by tracheal culture and serology at 1 wk followed by 3-wk intervals PV. Strain 6/85 was recovered from 0%-20% of vaccinates, but not from commingled pullets or sentinel birds. Strain ts-11 was recovered from 60%-90% of vaccinates and 0%-40% of commingled pullets but not from any of the sentinel birds. No birds in the 6/85 vaccine trial tested positive for MG antibodies by serology. MG enzyme-linked immunosorbent assays detected positive responses in ts-11 vaccinates (range = 10%-70%) at 42, 63, 84, and 105 days PV, and commingled pullets (10%) at 84 and 105 days PV. MG serum plate agglutination tests detected positive responses in 90% and 20% of ts-11 vaccinates at 42 and 105 days PV, respectively, and commingled pullets (10%) at day 42 PV. Clinical signs, morbidity, or mortality suggestive of pathogenic MG infection were not observed in any bird during either trial, and no gross lesions were observed at necropsy. Random amplified polymorphic DNA analysis was capable of distinguishing each of the vaccinal strains 6/85 and ts-11 from each other by their distinct DNA banding patterns.

A new mycoplasmal conjunctivitis was first reported in wild house finches (Carpodacus mexicanus) in early 1994. The causative agent was identified as Mycoplasma gallisepticum (MG), a nonzoonotic pathogen of poultry that had not been associated with disease in wild songbirds. Since the initial observations of affected house finches in the mid-Atlantic region, the disease has become widespread and has been reported throughout the eastern United States and Canada. By late 1995, mycoplasmal conjunctivitis had spread to an additional species, the American goldfinch (Carduelis tristis). This new disease exemplifies the rapid spread of a pathogen following introduction into a mobile wildlife population and provides lessons that may apply to emerging human diseases.

Seals and other Pinnipedia my carry a range of infectious agents which could be of clinical interest. A paramyxovirus infection caused epizootic seal death around danish coasts in 1988, but as the population is now recovering more contacts between seal and man must be envisaged. Bites and other forms of direct and indirect contact and carry a risk of development of seal (or blubber) finger. This entity encompasses oedema of the affect finger, swelling of the interphalangeal joint adjacent to the lesion, and no suppuration. The condition is extremely painful and may lead to residual dysfunction or amputation. There is circumstantial evidence that the condition is caused by mycoplasma, and Canadian researchers have identified three species, one of which has been directly linked to blubber finger. At the first medical contact after seal bites and other seal-inflicted lesions thorough cleansing with water and soap is recommended. Systemic therapy with tetracycline is recommended, but both fluorquinolones and macrolides may be efficacious.

In a prospective cohort study in a tertiary referral neonatal intensive care unit, the endotracheal secretions of 40 consecutively intubated newborn infants, less than 31 weeks' gestation, were examined weekly for the genital mycoplasmas and all other common bacterial pathogens. Fifteen (37%) infants were positive for Ureaplasma urealyticum and/or Mycoplasma hominis. There were no differences in gestation, birthweight, use of surfactant, or time on ventilator between the culture-positive and negative babies. Thirteen (87%) of the culture-positive group developed chronic lung disease (CLD) compared with 11 (41%) of the negative group (p = 0.0196). Of those culture-positive, 37% were not identified on the first specimen taken at the time of admission. These data suggest a significant association between infection with the urogenital mycoplasma and CLD and also stress the need for repeated cultures to identify these organisms.

Genital mycoplasmas play an important role in genitourinary tract disease. The purpose of this study was to isolate M. hominis and U. urealyticum from vaginal and throat swabs and urine from women sexually active or not. Samples were taken from women with (cases) or without (controls) genitourinary tract disease and were dipped inoculated into 1 ml of E broth with arginine or urea and ten-fold dilutions were done. Samples were incubated at 37 degrees C until phenol red indicator changed to color purple. Identification of species was done by polymerase chain reaction technique. M. hominis was identified with oligonucleotides that correspond to the nucleotide sequence of 16S rRNA gene and U. urealyticum was identified with oligonucleotides that correspond to the nucleotide sequence of the urease gene (Blanchard et al.). There was no statistical difference (X2 P > .05) between isolation percentages from vaginal swabs, while there was statistical difference between urine samples. These mycoplasmas were isolated in higher percentages from pubertal girls and were recovered until the fifth ten-fold dilution both from vaginal swabs and urine. For throat swabs they were only recovered from sexually active women.

Mycoplasma hominis is a significant pathogen in immunocompromised hosts, particularly organ transplant recipients. We describe two recipients of lung allografts from the same donor who had M. hominis pleuropulmonary infection during the immediate postoperative period. The most likely source of infection in these cases was the donor's respiratory tract. The slow-growing pinpoint colonies formed by M. hominis on routine bacterial culture medium may be easily overlooked and should be subcultured to mycoplasmal medium for definitive identification. The recommended management of this infection consists of drainage and antimicrobial therapy with tetracycline, clindamycin, or a fluoroquinolone. This report highlights the potential for M. hominis to be transmitted from donor to recipient during organ transplantation.

The rates of colonization by Ureaplasma urealyticum and Mycoplasma hominis were evaluated in 208 women at delivery and in their neonates. Mycoplasmas were isolated from the cervicovaginal specimens of 100 mothers (48.1%) and from the gastric secretions of 40 neonates (19.2%). The prevalences of U. urealyticum and M. hominis were 47.6% and 11.0% in women and 19.2% and 1.0% in neonates, respectively. Premature rupture of membranes was significantly associated with colonization of women by U. urealyticum (P = 0.031), and colonization of their neonates by U. urealyticum (P = 0.002) and/or M. hominis (P = 0.023). Forty-four selected strains of mycoplasmas were further characterized by arbitrarily primed polymerase chain reaction. All strains of U. urealyticum belonged to the parvo biovar of the species. Arbitrarily primed polymerase chain reaction demonstrated the similarity of strains isolated from mother-neonate pairs, confirming the importance of vertical transmission of mycoplasmas at delivery.

Five groups of 20 commercial leghorn hens near peak production were challenged with Mycoplasma gallisepticum, and medicated with enrofloxacin in the drinking water at 7-11, 21-25, or 7-11 and 21-25 days postchallenge (PC), a combination of lincomycin/spectinomycin at 7-11 and 21-25 days PC, or left as untreated controls. Egg production records were maintained, and all eggs produced during the 63 days following challenge were incubated for 18 days and then cultured for M. gallisepticum. All groups experienced marked egg production drops beginning about 1 week PC; production returned to near normal levels after approximately 3 weeks. Under the conditions of this study water medication did not prevent egg production losses, probably because of the delay in the onset of medication, but medication may have resulted in a more rapid recovery of egg production. Enrofloxacin was highly effective in reducing the level of egg transmission of M. gallisepticum, although a small number of eggs (0-0.3%) in the treated groups were culture positive after medication was begun. Only 1 of 2463 live embryos was culture positive after the onset of treatment. In the unmedicated control group, 12.8% of all eggs were culture positive. Lincomycin/spectinomycin also reduced egg transmission (3.4% of eggs were culture positive after treatment was initiated), but not as effectively as enrofloxacin. Most of the egg transmission occurred before the medication could have had an effect. Both enrofloxacin and lincomycin/spectinomycin reduced the number of dead-in-shell embryos.

We inoculated game-farm mallard (Anas platyrhynchos) eggs and 1-day-old birds with Mycoplasma anatis to determine its effect on hatching success and growth rates of ducklings. Inoculations of eggs reduced hatching success, hatchling size, and duckling growth rates, compared to controls. Intratracheal inoculations of 1-day-old birds did not affect growth rates. Hatchlings and 1-day-old ducklings grew much slower for the first 7 to 10 days when raised at 17 to 19 C, compared to controls raised at 30 to 35 C. The effect of cold stress on growth was greater than the effect of M. anatis infection; we found no synergistic effects between cold stress and M. anatis infection.

Colonization/infection of the genitals with Mycoplasma, group B Streptococci, and Chlamydia was studied in pregnant women. The course of gestation in women colonized with microorganisms was frequently aggravated by threatened spontaneous abortions, high incidence of hydramnion, late gestoses, pyelonephritis. For the newborns a reduced body mass and increased perinatal morbidity and mortality were characteristic. Transfer of microorganisms to the fetus and newborn was observed in 40-50% of cases and was not always associated with development of a disease. In cases of lethal outcomes of a neonatal disease pneumonia and placentitis were the constant morphological manifestations of the infection. In streptococcal and mycoplasmic infection the inflammation in the placenta was diffuse, involving the decium both in the placenta and in the extraplacental membranes.

Pathogen-free sentinel mice were placed in 7 animal rooms with different housing conditions and were serologically screened for antibodies to mouse hepatitis virus (MHV), pneumonia virus of mice (PVM), Sendai virus, reovirus 3, Theiler's mouse encephalomyelitis virus (TMEV), ectromelia virus and Mycoplasma pulmonis by enzyme-linked immunosorbent assays, at intervals after introduction. The most commonly detected antibody was against MHV, which was found in mice from 4 rooms, followed by PVM antibody in mice from 3 rooms. Seroconversion to Sendai virus and TMEV was detected in mice from one room each. No seroconversion to any of the antigens was found in 2 rooms. The common criteria of these 2 rooms were that they housed pathogen-free animals from a single source and that the access to the rooms was, purposely or not, restricted to people who had no contact to other mice. The study demonstrated the importance of husbandry and hygienic regimen on the prevalence of infectious agents in laboratory mice.

When animals are introduced to a specific pathogen-free (SPF) facility, care must be taken to avoid the possibility of disease transmission to the local colony. This study investigated the application of a combination of reproductive biotechnologies to establish a new disease-free colony of two rat strains, DarkAgouti(DA/Pit) and Wistar Furth(WF/Pit), from a stock known to be chronically infected with the following pathogens: Mycoplasma pulmonis, Kilham's rat virus, sialodacryoadenitis/coronavirus, and reovirus type 3. To eliminate the pathogens and optimize the use of animals, superovulation, embryo washing and trypsinization, and embryo transfer were used. Donors (DA/Pit and WF/Pit) were treated as follows: the mature females were synchronized by subcutaneous (s.c.) injection with 40 micrograms luteinizing hormone-releasing hormone agonist/animal on day -4. All immature and mature females were induced to superovulate by continuous s.c. infusion with a commercial porcine follicle-stimulating hormone (FSH) preparation (3.4 or 6.8 mg NIH-FSH-P1 units per day, respectively), beginning on the morning of day -2. On the afternoon of day 0, the animals received 30 IU human chorionic gonadotropin injected intraperitoneally and mated. From a total of 213 ova flushed from the oviducts of 16 programmed donors, 195 transferrable two-cell embryos were recovered. Two outbred strains of SPF rats, Long-Evans (LE) and Wistar (W), were used as recipients. These mature females (LE and W) were synchronized by using luteinizing hormone-releasing hormone agonist as described and made pseudopregnant by cervical stimulation. Two-cell embryos (DA/Pit and WF/Pit) were washed and trypsinized, then transferred to the oviducts of the pseudopregnant recipients (LE and W).(ABSTRACT TRUNCATED AT 250 WORDS)