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A survey for leprosy among 565 armadillos from Louisiana and Texas found IgM antibodies to the phenolic glycolipid-1 antigen of Mycobacterium leprae in 16% of the animals. There were no geographic trends in the distribution of prevalence rates between the sites and the disease probably has a much greater range. Repeat observations in one location showed significant seasonal variations in the observable antibody prevalence rate, but the yearly average remained similar. Infected armadillos tended to be heavier, and the females usually had plasma progesterone concentrations indicative of sexual maturity. Using these characteristics to stratify the populations into adult and sub-adult cohorts, variations in the observable leprosy prevalence rate were seen to be proportional to changes in the age structure of the populations. Leprosy appears to be maintained in steady state within some regions, and nearly a third of the adult armadillos in Louisiana and Texas harbour M. leprae.

The identity of herpes simplex virus type 1 (HSV-1) antigens that serve as targets for cytotoxic T lymphocytes (CTL) and their ability to induce protective immunity remain uncertain. In this article, we report the identification of the immediate-early protein ICP27 as a CTL antigen in H-2d mice but not in H-2k or H-2b mice. Calculation of the frequencies of H-2d-restricted virus-specific CTL demonstrated that approximately one-fourth of the total HSV-1-specific response was directed against ICP27. To define the location of this CTL epitope, four truncated derivatives of the ICP27 gene which place the epitope in a 217-amino-acid region (amino acids 189 to 406) near the central portion of the protein were constructed. Mice immunized with ICP27 were able both to induce HSV-1-specific CTL and to survive a lethal intraperitoneal challenge with virulent HSV-1. However, neither appreciable antibody nor delayed-type hypersensitivity responses were induced in immunized mice, and they were also unable to clear a local epithelial virus challenge. It appears that ICP27, although capable of inducing several aspects of the immune response, is by itself unable to provide complete immunity.

Infection and pyogranulomas induced by Corynebacterium pseudotuberculosis were experimentally reproduced in lambs. In two separate experiments, bacterial multiplication and dissemination were studied in 30 male lambs inoculated subcutaneously into the right ear with 1.1 or 1.5 X 10(8) viable C. pseudotuberculosis strain 19R. Infected lambs were necropsied at various times until the 28th day following inoculation. After a transient hyperthermia and a strong local inflammatory reaction, an abscess developed in the right ear from postinoculation day (PID) 6; it enlarged until PID 14 and stabilized thereafter and was associated with adenopathy of lymph nodes draining the head. Three acute phase indicators of inflammation were followed in 14 out of 30 lambs; plasma levels of copper and haptoglobin increased rapidly following inoculation whereas zinc levels decreased. The peaks were reached from PID 1 to 5, and thereafter the values came back slowly to the baseline. Antibodies against C. pseudotuberculosis exotoxin increased from PID 5 and reached a plateau on PID 21. Bacterial dissemination, assessed by the number of infected organs per lamb, was maximal on PID 16 and then stabilized until the end of the experiment. Lungs were infected in seven out of 18 lambs necropsied on PID 28. These results demonstrate a significant relationship between the clinical score of superficial lymph nodes or inoculation site and the infection level of these organs, and an early localization of pyogranulomatous lesions in regional lymph nodes. The subsequent development of the disease was related to the enlargement of these lesions and, in some animals, to a bacterial dissemination from primary sites of infection in the right prescapular lymph node and in the lung.

Vaccinia virus recombinants expressing glycoproteins B (vgB11), D (VgD52), E (gE/7.5 and gE/4B), G (gG-vac), H (gH-vac), and I (gI-vac) of HSV-1 were used to compare the protective response to these individual glycoproteins in the mouse. Glycoprotein D induced the best neutralizing antibody titers and the most increased rates of HSV clearance from the ear as well as good protection from the establishment of latent HSV infections in the sensory ganglia. Glycoprotein B also induced good neutralizing antibody titers and as great a protection from the establishment of latency as gD although the rate of virus clearance from the ear was not as great as after immunization with gD. Glycoprotein E induced weak neutralizing antibody but gG, gH, and gI did not show a neutralizing antibody response. At higher challenge doses of virus (10(6) PFU HSV-1 in the ear), gE induced a protective response by increasing the rate of virus clearance and reducing the acute infection of ganglia as compared to negative control immunized mice. However there was no protection from the establishment of latent infections after immunization with gE. No protective response was seen to gG, gH, or gl.

Eighty-six strains of Providencia stuartii (mainly of human origin) were characterized by one-dimensional SDS-PAGE of cellular proteins. The strains came from various countries; 52 were from urine, 11 from wounds, five from blood (one of these also from urine), four from ear infections, two each from faeces and sputum, one from 'alimentation' and nine from unknown sources. The protein patterns, which contained 45 to 50 discrete bands, were highly reproducible. The patterns of 46 Prov. stuartii strains (selected to represent the full range of protein pattern diversity) plus those of the type strains of the four other Providencia species were used as the basis for two numerical analyses. In the first, which included all the protein bands, the Prov. stuartii strains formed 13 clusters at the 88% S level. In the second analysis, in which the principal protein bands (in the 33.8-40.7 kDa range) were excluded, 45 of the 46 Prov. stuartii strains formed a single cluster at the 82% S level, whilst the four Providencia reference strains remained unclustered. The 40 strains of Prov. stuartii not included in the cluster analysis were assigned to a protein type by calculating their similarity with the strains in the database used for the cluster analysis. We conclude that high resolution PAGE combined with computerized analysis of protein patterns provides the basis for typing clinical strains of Prov. stuartii. Reference strains of each of the 13 PAGE types identified are available from NCTC for inclusion in future studies.

Aspiration of the exudate through the open perforation was performed in 68 children with chronic otitis media. The middle ear aspirate and a swab specimen of the external auditory canal were cultured aerobically and anaerobically. Seventy-eight isolates were recovered from the middle ears, 99 from the external ear canals, and 95 were present at both sites. Aerobes only were isolated from 33 patients (48.5%), nine (13.2%) had only anaerobes, and 26 (38%) had a culture that grew both aerobes and anaerobes. There were 99 aerobic isolates. Aerobes commonly recovered were Pseudomonas aeruginosa, Staphylococcus aureus, Proteus sp, Klebsiella pneumoniae, and Haemophilus influenzae. There were 74 anaerobes isolated. Anaerobes commonly isolated were anerobic Gram-positive cocci, Bacteroides sp, and Clostridium sp. These findings demonstrate the polymicrobial bacteriology of chronic otitis media in children. Cultures collected from the external auditory canals prior to their sterilization can be misleading. Reliable information can be obtained from the ear exudates when collected through the open perforation in the tympanic membrane.

2 groups of 44 specified-pathogen-free (SPF) mice, caged in groups of 4, were housed at weaning either in isolation in a building housing conventionally-reared animals, or in contact with those animals. 4 mice from each group were examined for microbiological flora and 4 for parasites at intervals for up to 90 days after transfer. Proscribed bacteria were isolated from the "in contact' group after 42 days and endoparasites were observed by 16 days and thereafter. No proscribed bacteria were isolated from the other group, although some endoparasites were observed by 16 days. Proscribed bacteria were shown to be present in the conventionally-reared animals at weaning and ecto- and endoparasites by day 16 and thereafter. It is suggested that it may be possible to maintain SPF animals outside a SPF Unit for short periods of time, and that with great care the animals remain free of proscribed microflora.

The clinical and epidemiologic features of vibrio infections occurring over 15 y in a hospital adjacent to the Chesapeake Bay were examined. Microbiologic techniques included the use of thiosulfate citrate bile salts sucrose (TCBS) medium on all stool specimens. Among 40 vibrio isolates from 32 patients, eight species were identified: V. parahaemolyticus (16), V. vulnificus (10), non-O1 V. cholerae (7), V. mimicus (3), V. hollisae (1), V. fluvialis (1), V. alginolyticus (1), and an unnamed halophilic vibrio. Sources included stool (13), wound (11), sputum (3), ear (3), bone (1), and gallbladder (1). While illnesses were diverse, they were relatively mild and self-limited with no mortality. The mild clinical spectrum and especially lack of mortality are in sharp contrast to the findings of previous reports. Even with the proximity to the bay and use of optimal isolation techniques, the demonstrated incidence of vibrio infections was low (1.6/100,000/y). The routine use of TCBS medium, which has been advocated for high-risk areas, was not cost-effective.

Pseudallescheria boydii is a recognized cause of mycetoma, a chronic fungal disease that usually affects the extremities. Isolated case reports have also implicated P. boydii in infections of other sites. We report the first large series (83 isolates) of P. boydii in 46 patients, including the second report of P. boydii brain abscess and disseminated infection in a noncompromised host. Between 1974 and 1984 at our institution, P. boydii was cultured from a variety of sites: respiratory tract, 36; soft tissue, 25; bone, 9; gastric aspirate, 4; maxillary sinus, 2; wound, 2; urine, 2; brain abscess, 1; ear, 1; and toenail, 1. Pulmonary colonization proved to be the most common form of pseudallescheriasis of the lung (34 of 36 cultures in this category); 28 of the 32 patients with pulmonary infections had received immunosuppressive therapy or had an underlying disorder. The importance of isolation of P. boydii from bone and soft tissue is supported in this series because all 9 cultures from bone and 21 of 25 cultures from soft tissue were associated with infection. Of 10 cases of infection, 5 were osteomyelitis and 2 were infected wounds; in addition, maxillary sinusitis, disseminated infection, and a lung abscess occurred in 1 patient each.

Of 2,169 patients screened in labor for vaginal group B streptococcal colonization, 164 (7.6%) had positive results. Five hundred twenty-four of the patients were screened in the antenatal period, and 57 patients with positive tests for group B streptococcus were treated in labor with intravenous ampicillin. Four of the treatment group gave birth to colonized infants but none became infected. Of the 136 untreated mother-infant pairs with positive tests, 62 neonates were colonized, nine became infected, and three died. In the presence of an attack rate of 6.6% among infants born to colonized mothers, antenatal screening and treatment in labor of mothers colonized with group B streptococcus will reduce neonatal colonization and infection.

Evidence is presented that the high susceptibility of armadillos to infection with Mycobacterium leprae cannot be explained solely in terms of body temperature because mutant mice maintained with a body temperature similar to that of armadillos do not become heavily infected with M. leprae. The depression of cell-mediated immunity accompanying the low body temperature is not sufficient to produce an overwhelming infection. The results obtained with M. marinum suggest that whereas lack of cell-mediated immunity or a low body temperature result in a moderately enhanced infection in the mouse a combination of both of these factors is required to produce an overwhelming infection involving the internal organs.

About half of pneumococci recovered from pediatric patients and one-third of isolates from adult patients yielded bacteriophages active against one or more of four noncapsulated indicator strains of pneumococcus. Strains of capsular types most frequently causing pediatric infections were associated with lysogeny. Classical restriction-modification phenomena have been demonstrated in vivo with some of the temperate phages, and correlation of restriction with the presence of one or the other of the two known pneumococcal restriction endonucleases has been established. The temperate phages differ serologically and in several other characteristics from virulent pneumococcal phages previously described. All pneumococcal phages so far studied can be classified into a minimum of three serological groups.

Acute and recurrent herpes simplex was studied after infection in the ear of two outbred and five inbred strains of mice. In all strains tested there was clinical evidence of infection, and a proportion of the mice became latently infected in the cervical ganglia. Six weeks after infection, when attempts were made to induce recurrent desease by stripping the ears of the mice with cellophange tape, a proportion of animals of each strain developed recurrent disease, characterized by erythema in the skin. At monthly intervals thereafter, the ears were stripped again and, on each occasion, a proportion of the animals developed recurrent disease, with the exception of Balb/c mice. The different reaction of Balb/c and other inbred strains might prove useful in studies on the mechanism of control of recurrent herpes simplex.

In a population of pregnant women, the prevalence of group-B streptococcal carriage was relatively low. During the 3rd trimester of pregnancy 5-6% of women haboured group-B streptococci and 8-3% were positive at the onset of labour. Some 42% of women who gave positive cultures in labour had given negative cultures during the 3rd trimester and 19% of women who were positive during late pregnancy were culture-negative in labour. The conversion of culture status observed in these women suggests that carriage may be intermittent or that new acquisition of genital-tract streptococci may occur in late pregnancy. The unpredictability of conversion diminishes the reliability of a single culture taken during the 3rd trimester of pregnancy.

Although the portal of entry and mode of spread of M. leprae in human leprosy are still uncertain, it is widely held that direct person-to-person skin contact is important. This assumption has ignored the fact that patients with highly bacilliferous leprosy have nasal as well as dermal infection and that, since M. leprae is shed predominantly from the nose, leprosy might be an airborne infection. The present study was designed to investigate this possibility with mice exposed to airborne infection with M. leprae. The conditions are described in which thymectomised-irradiated CBA strain mice exposed to M. leprae aerosols sustained an immediate lung retention of 1 X 10(5) bacteria. Fourteen to 24 months later, 33% (10 of 30) of the mice had countable numbers of acid-fast bacilli (greater than 2 X 10(4)) with the characteristics of M. leprae in one or more homogenates prepared from ears, foot pads, nose or lungs. Evidence is presented from the distribution of M. leprae that the infection had arisen from systemic spresd of bacilli initially entering the lungs rather than from multiplication of organisms locally retained there, or in the nose, at the time of airborne infection. The relevance of these results to the possible route of infection of leprosy in man is discussed.

Mice infected with three different isolates of herpes simplex virus (HSV) and treated with acyclovir (acycloguanosine; ACV) showed low levels of virus replication during the acute phase of infection. However, virus isolated from such treated mice did not show increased resistance to ACV. In contrast, resistant virus was readily isolated in vitro by passaging HSV in the presence of the drug. The degree of resistance was determined, in part, by the nature of the cells used to test the virus. The majority of ACV-resistant strains induced low or undetectable levels of HSV-specified thymidine kinase (TK), the enzyme responsible for phosphorylating ACV in infected cells. The TK-resistant strains were attenuated when injected into mice as indicated by reductions in virus replication, inflammation, and establishment of latent infections in sensory ganglia. The reduced virulence of the TK- strains was most marked after intracerebral inoculation, where the lethal dose was increased more than 100-fold compared with the parental isolates. However, one mutant is described which induced high levels of TK but was highly resistant to ACV and retained virulence for mice.

208 H. influenzae (HI) strains originating from the whole of Switzerland have been analysed for capsular serotype, biotype, and susceptibility to the following antibiotics: ampicillin, chloramphenicol, tetracycline, co-trimoxazole, and ceftriaxone. Serotype b is the commonest of the encapsulated strains. Biotypes II and III (respiratory tract) and I (invasive diseases) are the biotypes most encountered. Ceftriaxone is the most active among the antibiotics tested: 0.03 microgram inhibits 100% of strains, whether penicillinase producers (PP) or not. To evaluate the rate of resistant HI in Switzerland, 1883 isolates, 206 of which originated from invasive diseases (meningitis, epiglottitis, septicemia) have been considered. The PP rate is about 4%, irrespective of the group considered. Among the isolates from the invasive diseases, 3 were resistant to chloramphenicol, and 1 to ampicillin and chloramphenicol. The value of 4% for the PP strains is not very high; however, because of its powerful antibacterial activity and its high penetration into the cerebrospinal fluid, it seems reasonable to consider the use of a third generation cephalosporin, such as ceftriaxone, for the early treatment of meningitis in infants. If such a drug is indicated as a first-choice antibiotic for this meningitis it should be confined to this use only, to avoid the emergence of resistant strains.

Inbred strains of mice varying in susceptibility to intraperitoneal (i.p.) inoculation of HSV-1 were tested by inoculating 10(5) p.f.u. of the SC 16 strain into the ear pinna. Increase in ear thickness was less in resistant than in susceptible strains. In the resistant C57BL/6 strain, local replication of virus, spread to cervical ganglia and development of latent infections of the ganglia were all less than in susceptible DBA/2 mice; there was also less cellular infiltration of the inoculation site. Like resistance to i.p. inoculation, resistance to ear inoculation appears to be inherited as a dominant characteristic. The test provides a non-lethal method of distinguishing between resistance and susceptibility of inbred strains of mice to HSV-1 and may also be useful in defining resistance factors.

Of 243 children born after premature rupture of the membranes (PROM) 61 (26%) had the same bacteria in placental arterial blood, in ear swabs (taken deep from the external auditory canal) and in meconium. The predominant organisms were E. coli, Bacteroides fragilis, Streptococcus faecalis (enterococci) and Streptococcus agalactiae (group B streptococci). The infection rate was only 10% if the membranes had ruptured within 24 h of the onset of labour and 30% if the interval was longer than 24 h. Of 131 children born without premature rupture of the membranes but with risk factors for sepsis 9 (7%) had a positive blood culture with the same organism in the ear swabs and in meconium. The organisms were Streptococcus agalactiae (6 cases) and E. coli, Streptococcus faecalis and Klebsiella pneumoniae (one case each). Contamination of placental blood cultures was rare.

A modification of the classical CAMP test has been devised for the rapid detection of streptococci of serological Group B from human sources. The method was compared with detection based on the development of orange pigmented colonies on a starch-based medium and with detection by conventional methods. In a survey of vaginal carriage of Group B streptococci in parturient women, the modified CAMP test detected a carriage rate of 13.09%, the starch-based, pigment enhancing medium, 5.76% and the conventional methods, 8.38%. It proved to be particularly useful for detecting the organisms in the presence of other bacteria.

The indigenous microbial flora of the middle ear cavity of Mongolian gerbils, Meriones unguiculatus, was isolated, characterized, and identified, showing it to be sparse and transitory. Organisms, when found in the middle ear cavity, were most likely to be Staphylococcus epidermidis-like organisms. Cerumen from the external auditory canal of these animals yielded mostly staphylococci, coryneforms, and other gram-positive rods, including some anaerobic species. The nasopharynx supported a flora consisting mainly of staphylococci, lactobacilli, and coryneforms, with a smaller incidence and numbers of many other species. No mycoplasmas were cultured or seen in scanning electron microscope studies. None of the major pathogens of human otitis media were found; therefore, Mongolian gerbils are microbiologically acceptable candidates as a model for induced otitis media, using organisms isolated from human otitic infections.

A longitudinal study of colonization by group B streptococcus (GBS) was conducted in 93 pregnant women and 92 of their infants. Positive cultures were obtained from vaginal swab specimens on at least one occasion during pregnancy from 20.4% of the women. Three types of carriage were observed: chronic, transient, and intermittent. At the time of delivery, 12.9% of the mothers were colonized by GBS. GBS colonization occurred in 41.7% of the infants of the mothers colonized intrapartum. Only 1.2% of infants intrapartum culture-negative mothers were colonized. Infants colonized at birth were culture negative by 4 months of age. This study suggests that interruption of vertical transmission of GBS from mother to infant not only would influence the incidence of early-onset GBS disease but also might reduce the incidence of late-onset GBS disease.

The indigenous and the pathogenic microorganisms of the various body areas have been compiled but the list is constantly growing. The A.A. have examined the properties of the bacterial flora of the oropharynx and of the ear in regard of the etiology of the otitis and have hypothesized some mechanisms enhancing the growth of certain pathogenic bacteria.

A broth system was developed for rapid identification of the requirement for X factor (hemin), or V factor (NAD), or both for growth of Haemophilus species. This system was compared to growth around paper discs/strips impregnated with factors X and/or V. The broth system consisted of three tubes, each containing brain-heart infusion broth supplemented with V factor, X factor, or both. Each tube was inoculated with a saline suspension of an Haemophilus isolate, and the broths were shaken for aeration at 37 degrees C. Under these conditions turbidity or clumping was usually evident after 4-5 hr only in the broth(s) containing the required supplement(s). A few strains requiring only V factor required overnight incubation. One hundred fifty-six Haemophilus isolates were tested for growth around supplemented discs/strips or in supplemented broths: 129 were H. influenzae/aegypticus, 25 were of various species that required only V factor, and 2 were H. aphrophilus. Ten of 89 H. influenzae isolates from the respiratory tract were misidentified by satellitism. All isolates were correctly identified by growth in supplemented broths. The cost of the broth assay was about 60 cents/test, whereas the satellite assay cost about 120 cents/test. Serotyping and antibiotic sensitivity testing could be performed directly from the broth culture. Determination of X and/or V requirement by Haemophilus species with supplemented broths was sensitive, rapid, and inexpensive.

Among 827 isolates derived from 113 clinically healthy cats, 12 species of staphylococci were identified. Staphylococci were isolated from each cat and from 54.9% of the anatomic sites evaluated. A mode of 6 (range = 2 to 11) of the 11 anatomic sites evaluated per cat yielded staphylococci. A mode of 8 (range = 2 to 12) isolates were found per cat. Staphylococcus simulans was the most isolated (43.9% of total) coagulase-negative species. Moreover, S simulans was the most isolated species from each of the 11 sites evaluated and, except for the mouth and haircoat, comprised greater than 50% of the isolates from each site. Staphylococcus intermedius was the most isolated (13.5% of the total) coagulase-positive species. Three other species (S epidermidis, S xylosus, and S aureus) comprised 32.2% of the isolates, and 7 species (S haemolyticus, S hominis, S hyicus, S capitis, S warneri, and S saprophyticus) comprised 10.4% of the isolates. Six species (S intermedius [96 of 112 isolates], S haemolyticus [20 of 22], S sciuri [17 of 18], S warneri [10 of 13], S hyicus [10 of 10], and S capitis [7 of 8]) were isolated primarily from household cats. Only 1 species, S xylosus (75 of 87), was isolated primarily from cattery cats. Haircoat specimens (n = 452) yielded 508 isolates (61.4% of the total) distributed among all 12 staphylococcal species and included greater than 50% of the isolates of all species other than S simulans and S sciuri. A more heterogeneous population of staphylococci was isolated from household cats than was isolated from cattery cats.

A high incidence of group B streptococcal disease of the newborn in West Berkshire led to a prospective study of the condition. Cultures taken from 1090 babies shortly after birth showed that 65 (6%) were colonised with the streptococcus. Thirty of these babies were assigned to group 1. Bacteriological samples were taken from babies and mothers at birth and at four, eight, and 12 weeks, and also from fathers and siblings. Fifty uncolonised babies and their families were similarly studied and served as controls (group 2). In group 1,28 of the 30 mothers and 14 of the 28 fathers examined were colonised by group B streptococci. In group 2 the streptococci were isolated from three babies, 12 mothers, and 11 out of 45 fathers during follow-up. These findings suggest that group B streptococci are carried predominantly in the lower gastrointestinal and genitourinary tracts. Most families are lightly colonised, but in others maternal colonisation is stable and heavy and the incidence of paternal colonisation high. Results of serotyping suggest that sexual transmission occurs, which may explain the difficulty in eradicating the organism during pregnancy.

A total of 191 coagulase-negative staphylococci isolated from man were identified as Staphylococcus epidermidis on the basis of their biochemical properties. When classified according to the classification scheme suggested by BAIRD-PARKER (1972), 144 of the strains were found to belong to biotype 1, one strain was biotype 2, and four were biotype 3; the remaining 42 strains could not be classified within any of the 4 biotypes of this scheme. Using the classification scheme suggested by PELZER et al. (1973), 158 strains were found to belong to subgroup IIb, one was subgroup IIIb, four were subgroup IV, and 28 were subgroup V, with no strains remaining unclassified. The biochemical properties of the strains were not related to the site of isolation except that urease was produced by only 15 per cent of strains isolated from pus but by 81-92 per cent of strains isolated from a variety of other sources. The majority of the strains (64 per cent) were resistant to penicillin, while 72 per cent were sensitive to streptomycin.

Vaginal swabs were collected monthly from 100 asymptomatic Thai pregnant women as well as from 11 pregnant women with herpetic lesions of the vulva for isolations of HVH, mycoplasma and gonorrhoea. In asymptomatic mothers, 25% and 21% of cases were positive for HVH and mycoplasma respectively. Mixed infections of HVH and mycoplasma, and HVH and gonorrhoea were also found in 27% and 1% of cases respectively. Follow-up in asymptomatic pregnant women and those with herpetic lesions showed positive HVH fluctuations throughout the course of study. Positive HVH was recovered from 48% of amniotic fluid and 32% of breast milk of asymptomatic pregnant women with positive HVH genital isolates, and in 72.7% of aminotic fluid and 36.4% of breast milk in patients with herpetic lesions. HVH was also isolated from 84% of infants of asymptomatic mothers positive for HVH, and 100% of patients with herpetic ulcer. HVH was isolated most frequently from the throat and also from nose, eyes, and ears but with less frequency. IgM antibodies were found in three infants born of asymptomatic mother and in one infant of a mother with herpetic lesion. The low percentage of IgM antibody was interpreted to mean that the HVH isolated from the newborn infants were acquired during passage through the birth canal.

407 strains of pseudomonas aeruginosa form in-patients and out-patients were serotyped according to Habs' schema. 11.3% of the isolates were non-typable and among the other strains serotypes 6 and 10 were the most prevalent (20.4 and 14.0%, respectively). Type 14 was not observed. Most of the strains isolated from sputum were non-typable, whereas serotype 6 predominated in specimens from urine, wounds and ears. The susceptibility of the isolates to antipseudomonal agents was estimated: 4.7% of the isolates (mainly serotypes 2, 4, and 11) were resistant to gentamicin and among these strains parallel resistance to tobramycin and netilmicin was observed in 47.4%.

A longitudinal study of the cervical and vaginal microflora of 131 pregnant women showed a similar range of organisms at first visit (up to 16 weeks), at 28 weeks and at 36 weeks of pregnancy. Twenty different groups or genera of microorganisms were recovered, predominantly lactobacilli. There was a fall in the isolation rate of organisms in the mothers 6 to 8 weeks after delivery. Lactobacilli and yeasts including Candida albicans were recovered less frequently whereas the incidence of Escherichia coli and group B streptococci increased.Infants born to these mothers were swabbed within 24 hours of delivery and yielded organisms from the umbilicus, ear and mouth in 24%, 33% and 38% of cases respectively. Alpha haemolytic streptococci and Staphylococcus aureus were the predominant organisms. Sixteen different groups or genera were isolated.The isolation rates in non-pregnant women attending a `well-women' clinic were similar to those in the postnatal mothers; few women of 60 years or more were colonized.

A total of 464 Haemophilus influenzae strains, most of them fresh clinical isolates, have been classified by chemotyping --a combination of auxotyping and biotyping. Seven auxotests and four other biochemical tests allowed recognition of 56 types. These were to a degree site-specific. H. influenzae of capsular type b proved almost without exception to belong to one chemotype, and 24 of 33 strains assigned to this chemotype were capsulated. When surgical-ward isolates of H. influenzae were typed, the results suggested that some cross-infection had occurred.

The pathogenesis of herpes simplex virus (HSV) infection is now well understood. After humans or experimental animals recover from primary infection, the virus remains latent in sensory ganglia of the peripheral nervous system. Latency, for the most part, remains unresolved, and elucidating the mechanisms involved with latency has proved difficult. The requirement for unravelling HSV latency is the availability of a reproducible animal model. Previously, the mouse ear model has been extensively characterized; however, many studies using this model have involved female mice only despite evidence that recurrent HSV infection in humans may vary by gender. We inoculated male and female mice subcutaneously in the pinna with varying amounts of one of four strains of HSV and monitored the mice for signs of primary infection. Following recovery from primary infection, mice were induced to develop recurrent disease. In addition, we attempted to isolate virus from dorsal root ganglia of mice suspected of harboring latent virus. There were no differences in the response of male and female mice to either primary infection or artificially induced recurrent disease when inoculated with the same virus. Differences were noted when female mice were inoculated with different strains of virus.

78 Staphylococci isolated from mouth, throat, nose, ear passages and skin lesions were typed with 22 basic phage types. 68 of 78 staphylococci were typed. 45 of these (66%) could be typed with RTD, and 23 (33.8%) with 1000 X RTD. When phage grouping is considered, 14 out of 68 strains were from Group III and 12 out of 52 strains isolated from nose were from Group I phage.

Pseudomonas aeruginosa was isolated from the ears of 18 of the 25 members of a team of competitive swimmers who complained of painful discharging ears. This group of swimmers trained twice daily in the pool, in the early morning and late afternoon. In contrast swabbing of the ears of a similar group of 54 competitive swimmers who used the pool only in the afternoon revealed only one swimmer with P. aeruginosa. Investigation of the swimming pool revealed that chlorination was often inadequate when the first group of swimmers were training in the early morning. Strains of P. aeruginosa were isolated from various sites around the pool and from the bag of a vacuum used to clean the pool. Pyocin typing, serotyping and phage typing were performed on all isolates. The dominant strain recovered from the swimmers' ears was found to be almost identical to that from the vacuum bag and belonged to serotype 0--11 which has been particularly associated with outbreaks of P. aeruginosa infection in whirlpools in the United States. These results support the hypothesis that there is a direct correlation between the development of otitis externa and swimming in water contaminated with P. aeruginosa.

The conditions of helium saturation diving promote the proliferation of Gram-negative bacterial species in the external auditory meatus of divers. These changes in flora occurred in the absence of operational diving, that is, no contact with water. The colonising bacteria were autogenous in origin and cross-colonisation was observed between divers. On return to normal atmospheric conditions the aural flora became predominantly Gram-positive again within 48 hours.