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An enzyme-linked immunosorbent assay was compared with an indirect fluorescent antibody test for its ability to detect antibodies to the Lyme disease spirochete in sera of naturally infected humans, dogs, and white-footed mice and experimentally infected Swiss mice. Ninety-five percent of the total 123 sera analyzed reacted similarly in both tests. For 36 human sera, the correlation coefficient (r = 0.47) for logarithmic transformations of indirect fluorescent antibody and enzyme-linked immunosorbent assay titers was significant at P less than 0.01. Within each mammalian species, mean titers for indirect fluorescent antibody and enzyme-linked immunosorbent assay antibodies were within three-fold. Comparisons of different naturally infected mammals revealed relatively higher average titration endpoints in both tests for patients with Lyme disease. Human sera also had the widest range of titers. Both methods proved satisfactory for serological confirmation of prior spirochetal infections.

In a comparison of dengue type 2 immune mouse ascitic fluid immunization schedules, a schedule in which adjuvant vaccines were not used produced neutralizing antibody titers that were specific and a mouse mortality rate that was lower, resulting in a greater yield of ascitic fluids. In the schedules in which emulsified adjuvant vaccines were used, the quality of the emulsion had little effect on antibody titer produced.

An indirect immunofluorescence test was used during 1982-1983 to identify antibodies to Lyme disease spirochetes in humans, white-footed mice, and raccoons. Serologic tests detected IgM or total Ig antibodies in serum samples from 67 persons. Onset of illness, as marked by erythema chronicum migrans (ECM), occurred mainly during July and August. The majority of the persons with Lyme disease lived in south central and southeastern Connecticut. Analyses also verified prior spirochetal infections in 29 of 323 (9 percent) white-footed mice and in three of 34 (9 percent) raccoons captured at sites with or without evidence of human infections. Results indicate potential for Lyme disease at numerous localities in Connecticut.

Immature and adult ixodid ticks were collected during 1983 and 1984 in Newtown, Connecticut, an area endemic for Rocky Mountain spotted fever (RMSF), to determine prevalence of infection by spotted fever group (SFG) rickettsiae. Direct fluorescent-antibody (FA) staining revealed SFG organisms in 6 (1.8%) of 332 Dermacentor variabilis larvae, 5 (7.8%) of 64 D. variabilis nymphs, and in 2 (40%) of 5 Ixodes cookei nymphs removed from small- and medium-sized mammals. Hemolymph tests detected rickettsia-like organisms in 15 (8.8%) of 170 D. variabilis adults; 8 specimens retested by direct FA were negative. In contrast, hemocytes from 5 (8.6%) of 58 Ixodes texanus females contained organisms that stained positively in both hemolymph and direct FA tests. An indirect microimmunofluorescence test identified specific antibodies to Rickettsia rickettsii, the etiologic agent of RMSF, in serum samples from a chipmunk, raccoons, and white-footed mice. Results indicate that immature or adult ticks of at least three species may be involved in the maintenance and transmission of SFG rickettsiae at Newtown.

Treatment of CVS-11 rabies adsorbing suspensions and street rabies infected mouse brains with gamma radiation resulted in inactivated reagents that are safer to distribute and use. These irradiated reagents were as sensitive and reactive as the nonirradiated control reagents.

Rabbits were inoculated with purified antigen preparations of Coxiella burnetii and representative species of the spotted fever and typhus groups of rickettsiae. Their antibody responses were monitored by complement fixation tests; high-titered antisera were fractionated with ammonium sulfate and then labeled with fluorescein isothiocyanate by the dialysis method. The conjugates had homologous 3+ staining titers of 1:256 to 1:2,048 and did not exhibit nonspecific staining. The Rickettsia rickettsii, R. conorii, and R. akari conjugates reacted only with rickettsiae of the spotted fever group; the R. canada, R. prowazekii, and R. typhi conjugates were specific for the typhus group rickettsiae; and the C. burnetii conjugate stained only homologous organisms. One of these conjugates (R. rickettsii) is currently being used to identify rickettsiae in clinical specimens and has already proven its value as a diagnostic tool.

Using a new enzyme immunoassay (EIA) and standard immunodiffusion (ID) and complement fixation techniques for antibody to the A antigen of Blastomyces dermatitidis, we tested serum from 27 patients with blastomycosis diagnosed histopathologically or by culture; 20 with diagnoses made during 1981 through 1983 (Group A) and 7 during 1974 through 1976 (Group B). We also studied 30 control subjects with Mycoplasma pneumoniae infection (17 subjects), histoplasmosis (6 subjects), coccidioidomycosis (1 subject) and no known disease (6 subjects). Detectable antibody by all 3 tests was present more often for Group A than for Group B, possibly because of delay in testing. Enzyme immunoassay was the most sensitive test; a 1:8 or greater titer was present in acute-phase serum of all Group A patients tested, and a 1:64 or greater titer was associated with disseminated disease (p = 0.003). A positive ID was also more common in disseminated (88%) than in localized (33%) disease. Enzyme immunoassay titers of 1:16 were present in 4 control subjects, 3 with histoplasmosis. The 100% predictive values of a negative EIA and positive ID suggest that these tests are useful for serologic screening (EIA) and serologic confirmation (ID) of suspected blastomycosis, particularly in disseminated disease. Enzyme immunoassay titers of 1:32 or greater strongly support the diagnosis and titers of 1:16 or less may indicate localized disease or be nonspecific. None of the serologic tests predicted disease progression or reactivation.

Procedures for inactivating rabies virus in reagents used for the fluorescent rabies antibody test are described. Mouse brain adsorbing suspensions containing greater than or equal to 10(9) 50% lethal doses of virus per ml were rendered noninfectious by treatment with 0.1% beta-propiolactone or by heating at 56 degrees for greater than or equal to 30 min. Viable virus in tissue impression smears was inactivated by acetone fixation at 50 degrees C for greater than or equal to 30 min or by immersion in 0.1% beta-propiolactone at 37 degrees C for 2 h. Inactivated reagents gave specific and sensitive reactions in the fluorescent rabies antibody test.

During 1980-1982, white-footed mice (Peromyscus leucopus) were captured in Newtown, Connecticut, an area where Rickettsia rickettsii, the etiologic agent of Rocky Mountain spotted fever, is thought to be enzootic. An indirect microimmunofluorescence test identified specific antibodies to this organism in 16 of 237 (7%) sera: titration end points for 14 samples were relatively high (1:128-1:2048). Antibodies were detected in mice during 1980 and 1981 with monthly prevalences varying from 8 to 22%. These results suggest that P. leucopus may be involved in the ecology of R. rickettsii and that these rodents can be included along with other mammals to monitor spotted fever rickettsial infections in nature.

Suspension cultures of BHK-21/13s cells infected with either A/Hong Kong/8/68 or B/Massachusetts/3/66 strains of influenza were used to prepare type-specific influenza ribonucleoprotein-immunizing antigens. These antigens were used in comparing four immunization schedules in the production of immune mouse ascitic fluids. Large volumes of ascitic fluids were obtained by these schedules. These fluids contained type-specific complement-fixing antibody and were devoid of nonspecific host tissue or heterologous cross-reactions.

Suspensions of herpes simplex virus types 1 and 2, cytomegalovirus, and parainfluenzavirus type 2 were inactivated within 24 h when treated at 37 degrees C with 1 mg (5.05 mM) of copper-catalyzed sodium ascorbate per ml. The infectivity titer of respiratory syncytial virus was reduced substantially after 24 h but required 48 h for inactivation. Under these conditions, inactivation of these viruses was also successfully achieved with 5.68 mM catalyzed ascorbic acid. Copper (Cu2+), when added with the ascorbate solution at 5 micrograms/ml (0.022 mM), exhibited a catalytic effect on the inactivation of these viruses. The rate of inactivation was affected by the incubation temperature, time of exposure, and the virus concentration. Ascorbate concentrations as high as 10 mg/ml (50.5 mM) demonstrated only a minimum increase in effect on viral inactivation. The loss of infectivity did not alter either the hemagglutination or complement fixation qualities of the antigens.

A case of scorpion (Parabuthus species) envenomation causing severe respiratory failure is presented. Systemic effects, which included muscular weakness, hypertonus and bulbar dysfunction, developed 8 hours after poisoning; this emphasizes the importance of close observation of victims of envenomation. Treatment included the administration of scorpion antivenom (SAIMR) and mechanical ventilation for 4 days.

The peri-operative management of elderly patients presents a variety of problems to the anaesthetist. These include organ dysfunction associated with the ageing process and the high incidence of serious disease affecting major organ systems. In addition, elderly patients commonly require multiple drug therapy. As such they are likely to suffer adverse drug effects and interactions, events more liable to occur in these patients as a result of both pharmacokinetic and pharmacodynamic factors. Occasionally serious interactions may occur with drugs used during anaesthesia. The importance of adequate pre-operative assessment and preparation cannot be overemphasized, as well as the need for a team approach to the management.

The blood gas/acid-base status of normal healthy Black, Indian, Coloured and White pregnant women was measured. All groups exhibited evidence of hyperventilation (decreased) PaCO2 relative to the non-pregnant state, with compensatory metabolic adjustment. Arterial oxygen tensions (PaO2) were significantly lower in the Black and Indian groups compared with their White counterparts (P less than 0,01). Differences between the former two series and the Coloured group, however, just failed to reach statistically significant levels (0,1 less than P less than 0,05). The possible causes of a lowered PaO2 during pregnancy and their relevance to obstetric anaesthesia are discussed. A further study using a more sophisticated protocol is planned in an attempt to delineate the causes of these important differences.

Mouse immune ascitic fluid has become a primary source of antibody for diagnostic, reference, and research work in many virus laboratories. The inherent disadvantage of ascitic fluid is that it repeatedly forms clots and subsequently loses volume. The acid-precipitation method of Chiewsilp and McCown eliminates the clot formation and does not appreciably alter the antibody titers for several arboviruses, varicella, rabies and influenza viruses.

White-tailed deer (Odocoileus virginianus) were examined for the tick, Ixodes dammini, and sera were analyzed for antibodies to spirochetes during 1982. Of the 323 animals inspected in four areas endemic for Lyme disease, 188 (58%) had adult ticks; parasitism ranged from 43% at Haddam to 82% at East Lyme. Direct and indirect fluorescent antibody tests detected spirochetes in 18 of 133 (14%) ticks. Indirect immunofluorescence tests revealed antibodies at titers of 1:64-1:4,096 to this bacterium in 93 (28%) of the 332 sera assayed. There is a close correlation among the distribution of spirochete-infected I. dammini, deer with antibodies, and human cases of Lyme disease.

Sixty patients with fractured neck of femur and scheduled for surgical correction were randomly allocated to receive one of three anaesthetic techniques: general anaesthesia; spinal analgesia; psoas compartment block. The patients in the local anaesthetic groups also received a light general anaesthetic. There was little difference in the pre-, intra- and postoperative events, and no difference in postoperative mortality.

Ticks were screened for spirochetes and serum samples from white-tailed deer (Odocoileus virginianus) were assayed for antibodies to Borrelia burgdorferi during 1983-1984. Using fluorescein isothiocyanate-labeled rabbit antibodies produced to B. burgdorferi, the etiologic agent of Lyme disease, spirochetes were detected in Ixodes dammini (10.5% of 1,193) and Dermacentor albipictus (0.6% of 157) adults from Connecticut, I. dammini nymphs (49.1% of 108) and adults (64.7% of 99) from Armonk, New York, and in I. scapularis (0.4% of 531) and Amblyomma americanum (3.5% of 173) adults from North Carolina. Infected ticks were either seeking hosts or feeding on deer during the summer and fall. Direct fluorescent antibody staining also revealed spirochetes in two larvae of I. scapularis that emerged from eggs deposited by separate females in the laboratory. Using indirect immunofluorescence tests, antibodies to B. burgdorferi were identified in white-tailed deer living in tick-infested areas of all three states. Aside from minor cross-reactivity, there was no serologic evidence of Treponema or Leptospira infections. Ixodes dammini is a primary vector of B. burgdorferi in northeastern United States, but in North Carolina, other ixodid ticks may transmit this spirochete to humans and wildlife.

Three patients with respiratory failure resulting from miliary tuberculosis had a characteristic clinical presentation that included a long history of a prominent cough, dyspnea, weight loss, tachycardia, tachypnea, pulmonary adventitious sounds, and hepatomegaly. Hematologic investigation showed a normal white cell count with marked left shift in the morphology of white cells in all three patients, and evidence of disseminated intravascular coagulation in one patient. In only one patient was the initial sputum positive for acid-fast bacilli; in the others, invasive diagnostic procedures including lumbar puncture, bone marrow trephine, and open-lung biopsy were necessary for diagnosis. Miliary tuberculosis should be suspected in patients with adult respiratory distress syndrome of unknown etiology. Simple diagnostic procedures such as sputum, bronchial brushings, and urine examination should be followed by bone marrow trephine, liver biopsy, transbronchial lung biopsy, and lumbar puncture if physical signs of meningitis are present.

Enhancement of neutralization of Sindbis, Venezuelan equine encephalitis, Eastern equine encephalitis, Western equine encephalitis, and St. Louis encephalitis viruses by labile serum factor (LSF) in human serum and plasma was demonstrated. Human serum and plasma could be diluted 1:8 and 1:16 and still retain some LSF activity. Satisfactory storage temperatures for retention of LSF activity were -20 or -56 C. Repeated freeze-thaw cycles of serum did not alter LSF activity, but the activity was completely eliminated by heating at 56 C for 5 min. LSF of human serum equally enhanced neutralization by Sindbis immune mouse and rabbit sera; these results suggest a lack of species specificity. Rehydrated lyophilized gunea pig complement did not restore LSF activity to heated human plasma. Serum components responsible for LSF activity were not dialyzable. Discovery of fresh serum without LSF activity established the need to pretest all sera used as LSF sources.

Horses were immunized by a variety of inoculation procedures designed to determine the most efficient method of producing antisera to adenovirus types 25 to 31. The procedures evaluated included immunization by (i) direct intravenous (iv) injection, (ii) iv infusion, (iii) intramuscular (im) injection of virus with and without Freund's incomplete adjuvant, (iv) combined iv and im injections, and (v) combined iv infusion and im injection. The im schedule (no. 3) was superior to the others in terms of immunizing antigen and time required, and hemagglutination-inhibition (HI) and serum-neutralizing (SN) antibody levels produced. HI and SN tests performed with sera before and after heating at 56 C for 30 min showed that heat-inactivation was not necessary for tests with equine antisera.

Human sera were treated with kaolin, acetone, and dextran sulfate to determine the best method for removing nonspecific hemagglutination inhibitors. Results indicated that on surveys for group A, group B, and some group C arbovirus HI antibodies, dextran sulfate treatment of sera could be used effectively. This method, however, has limited usefulness for detecting HI antibody for a number of arboviruses, particularly some members of the Bunyamwera supergroup since nonspecific inhibitors for these antigens were not completely removed. HI antibodies in sera drawn early after dengue and Venezuelan equine encephalitis infection were detected more readily after dextran sulfate treatment than after kaolin treatment. Kaolin, but not dextran sulfate, was shown to remove antibody from IgM fractions of sera.

Thin-section electron microscopy was carried out on Vero green monkey kidney cell cultures infected with some viruses of the newly constituted arenovirus group. Junin, Machupo, Amapari, Pichinde, Parana, Tamiami, and Latino viruses were morphologically identical and indistinguishable from lymphocytic choriomeningitis virus, the prototype virus of the group. Virus particles were round, oval, or pleomorphic, 60 to 280 nm in diameter, and matured via budding from plasma membranes. Most characteristically, particles contained various amounts of homogeneous, 20- to 25-nm, dense granules; these granules in large masses also formed distinctive intracytoplasmic inclusions. In negative-contrast preparations from infected Vero cell culture supernatant fluids, several of the viruses appeared as pleomorphic membrane-bound forms with rather pronounced surface projections. Most particles were between 90 and 220 nm in diameter, although some reached 350 nm in their longest dimension. Internal structure was not resolved by negative-contrast electron microscopy. All observations supported the current delineation of a distinct arenovirus group.

Hemagglutinating and complement-fixing antigens of La Crosse virus (California arbovirus group) were produced in serum-free suspension cultures of BHK-21/13S cells. The appearance and production of these antigens were correlated with the titer of infectious virus. No significant differences in antigen titers were produced by varying virus dose 10-fold. Hemagglutinin appeared 6 to 8 hr after inoculation and reached peak titer in 14 to 22 hr. Both beta-propiolactone and Tween 80-ether treatment inactivated infectious virus in the antigens. Unlyophilized antigen was stable at -60, 5 and 24 C for at least 117 days but not for 1 year. Lyophilized antigen was stable for at least a year, however, at -20 and 5 C. Cell culture-produced antigen was more sensitive than brain-produced antigen in detecting hemagglutination inhibition antibody in human sera.

During the 1969 dengue epidemic in Puerto Rico, human sera and Aedes aegypti mosquitoes were collected for virus isolation and identification. Three methods of isolation were used and compared. In the first method, we inoculated newborn mice by the intracranial route, noted any signs of illness, and serially passed specimens in mice until virus was isolated. In the second method, we inoculated tube cultures of LLC-MK(2) cells, noted any cytopathic effect (CPE), and assayed fluids for virus by plaque formation in LLC-MK(2) cell monolayers. The third method was different from the second only in that the original specimens were first inoculated into fluid cultures of Singh's A. albopictus cells. No significant CPE was seen in LLC-MK(2) cultures; however, distinct syncytial CPE was observed in A. albopictus cells. About the same number of virus isolates were made in each isolation system. Virus isolates from both sera and mosquitoes were identified as dengue type 2 by a plaque-reduction neutralization test in LLC-MK(2) cells. The utility of the three methods, individually or in combination, is discussed and related to diagnostic and epidemic situations.