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Biomedical subjects

C H Calisher

Publications and source records attributed to C H Calisher.

At least 109 records · Page 6Linked to original sources
PubMed1984

Human infections with La Crosse virus in Georgia, 1982.

Eight cases of central nervous system infection due to La Crosse (California serogroup) virus were detected in Georgia children in 1982. The patients were residents of the state, without histories of travel away from the vicinities of their homes during the 30 days before the onset of their illnesses. All were hospitalized with a diagnosis of aseptic meningitis or encephalitis; none had sequelae. Onset dates were from May 1 to Aug 30. Distribution of cases within the state suggested that active transmission of La Crosse virus occurred at least in the southeast quadrant of the state. The epidemiology and natural cycle of La Crosse in the southeastern United States are briefly discussed.

Aedes↗
PubMed1984

Immunoglobulin M antibody capture enzyme-linked immunosorbent assay for diagnosis of St. Louis encephalitis.

Sera from patients with St. Louis encephalitis were tested with an immunoglobulin M (IgM) antibody capture enzyme immunoassay (MAC ELISA). The assay used five reagents: antihuman IgM, test serum, sucrose-acetone-extracted mouse brain antigen, broadly cross-reactive flavivirus monoclonal antibody conjugated to alkaline phosphatase, and substrate (p-nitrophenyl phosphate). MAC ELISA endpoint titers correlated (r = 0.893) with the absorbance value of a 1:100 dilution of patient serum. Significant (fourfold or greater) changes in the endpoint titers between paired sera corresponded to a critical ratio (ratio of absorbance values at the 1:100 dilution) of greater than or equal to 1.3. IgM antibodies were detected in 71% of patients bled at 0 to 3 days after the onset of illness, in 99% bled at 4 to 21 days, and in 91% bled at 22 to 67 days. Thereafter, the IgM seropositivity rate declined; however, 29% of sera were still positive at 115 to 251 days after the onset of illness. MAC ELISA titers were significantly correlated with hemagglutination inhibition (r = 0.258) and neutralization (r = 0.711) titers. Because IgM antibodies appeared early and waned rapidly, a diagnosis was made on the basis of a decrease in titer more often by MAC ELISA than by hemagglutination inhibition, complement fixation, or neutralization tests. IgM antibodies generally showed a high degree of specificity; heterologous cross-reactions were, however, present in 4 of 14 sera examined. The MAC ELISA is useful for the rapid, early diagnosis of St. Louis encephalitis.

Antibodies, Viral↗
PubMed1984

Arbovirus studies in the Guajira region of Venezuela: activities of eastern equine encephalitis and Venezuelan equine encephalitis viruses during an interepizootic period.

Repeated outbreaks of Venezuelan equine encephalitis (VEE) in humans and equines in the Guajira region of Venezuela suggested a sylvatic focus of an epizootic subtype of VEE virus. A surveillance system was established, and virus isolations were attempted from 67,760 mosquitoes as well as sentinel hamsters. Sixteen isolates of eastern equine encephalitis (EEE) and a strain of Itaqui virus were recovered from mosquitoes, and 60 isolates of EEE, two of VEE, and two of Itaqui viruses were recovered from tissues of sentinel hamsters. The VEE virus isolates were shown to be closely related antigenically to prototype VEE ID and the EEE virus isolates were shown to be more closely related to the South American than the North American variety of EEE virus. Evidence for the presence of VEE and EEE viruses in small wild vertebrates was obtained from serologic testing. This study showed, for the first time, the enzootic presence of both VEE ID and EEE viruses during a nonepizoodemic period in the Guajira region.

Alphavirus↗
PubMed1984

Arbovirus studies in southwestern Venezuela during 1973-1981. II. Isolations and further studies of Venezuelan and eastern equine encephalitis, Una, Itaqui, and Moju viruses.

Increasing utilization of arable land in southwestern Venezuela has led to a potential increase in human exposure to arbovirus infections. Since previous studies in the Catatumbo region of this area documented the presence of eastern equine encephalitis (EEE) and Venezuelan equine encephalitis (VEE) viruses, an attempt was made to study the transmission and maintenance of these viruses from 1973 to 1981. Isolations of EEE, VEE ID strains, Una, Itaqui , and Moju viruses were repeatedly obtained from mosquitoes, mostly Culex ( Melanoconion ) spp. and sentinel hamsters. The results indicate that these viruses constitute a potential hazard to public health in the area. Further, the strategic location of the Catatumbo region, between enzootic tropical foci of arboviruses, may provide circumstances and conditions for study of both enzootic maintenance and movement of these viruses.

Aedes↗
PubMed1984

Isolation of Thogoto virus from ticks in Portugal.

An agent pathogenic for mice was isolated from Rhipicephalus sanguineus ticks collected from goats from Vila Vicosa , Portugal. The virus was shown serologically to be closely related to or identical with Thogoto virus, which had previously been isolated from ticks over a wide geographic area including Sicily, the African continent, and Iran.

Animals↗
PubMed1984

The effect of immune globulin on the response to trivalent oral poliovirus and yellow fever vaccinations.

To assess whether immune globulin may be administered concurrently with trivalent oral poliovirus vaccine (OPV) or yellow fever vaccine, antibody responses were studied in Peace Corps volunteers embarking for overseas duty in 1978. Of 200 volunteers who received OPV, 192 (96%) had pre-existing neutralizing antibody to at least 2 poliovirus types; of 160 yellow fever vaccinees, 24 (15%) had pre-existing 17D yellow fever antibody. Each volunteer received 5 ml of immune globulin, 0-7 days before, 3-5 days after, or 28-32 days after vaccination. This last group was designated the control group. Of the volunteers who received immune globulin 0-7 days before vaccination, 71% 72%, 49%, and 82% responded to poliovirus types 1, 2, and 3, and yellow fever, respectively (response was defined as a 4-fold or greater rise in serum neutralizing antibody titre between baseline (0-7 days before vaccination) and follow-up (15-40 days after vaccination)). These rates did not differ significantly from those in persons who received immune globulin 28-32 days after vaccination (61%, 60%, 51%, and 83%, respectively). Thus, among individuals who, for the most part, were immune to poliomyelitis but not to yellow fever, immune globulin did not decrease the antibody response to OPV or to yellow fever vaccine when given 0-7 days before vaccination.

Administration, Oral↗
PubMed1983

Serodiagnosis of western equine encephalitis virus infections: relationships of antibody titer and test to observed onset of clinical illness.

Sera from horses and human beings with clinically diagnosed western equine encephalitis (WEE) virus infections were tested for hemagglutination-inhibition (HI), complement-fixation (CF), and neutralizing (N) antibody to WEE virus. These tests confirmed infection in 43.8% (HI), 56.3% (CF), and 80.4% (N) of horses and 54.5% (HI), 59.1% (CF), and 77.3% (N) of human beings. Use of the N test as an adjunct to the HI and CF tests increased the likelihood of serologic confirmation to 91.7%. In both horses and human beings, N antibody increased steeply at the end of the 1st week after onset. The results suggested that the presence of a high HI, CF, and/or N antibody titer in a single serum obtained from horses during the acute phase of illness caused by WEE virus can be used as presumptive evidence for infection with this virus.

Animals↗
PubMed1983

Identification of new Guama and Group C serogroup bunyaviruses and an ungrouped virus from Southern Brazil.

From 1975 to 1978, 36 viruses were recovered from humans, bats, birds, sentinel mice and hamsters, and from mosquitoes collected in Coastal Brazil in the state of São Paulo. Identifications of 22 of these 36 viruses have been reported. Six of the remaining 14 isolates were shown to be Guama serogroup bunyaviruses. Two of these six were strains of a newly recognized virus for which the name Cananeia virus is proposed; another is a second newly recognized Guama serogroup virus for which the name Itimirim virus is proposed; a fourth is a strain of Bertioga virus and the other two are strains of Guaratuba virus. Before these studies Guaratuba virus was considered an ungrouped bunyavirus, but cross testing by complement-fixation demonstrated that this virus, and Mirim virus as well, should be considered members of the Guama serogroup. Another six viruses were shown to be strains of a single, newly recognized Group C bunyavirus for which the name Bruconha virus is proposed. Two strains of a single virus were shown by electron microscopy to belong to the family Bunyaviridae, but serologic relationships with other members of this family of viruses were not found; the name Enseada virus is proposed for this newly recognized agent.

Animals↗
PubMed1983

Occurrence of La Crosse (California serogroup) encephalitis viral infections in Illinois.

La Crosse (LAC) virus (California encephalitis serogroup) was identified as the etiologic agent of disease in 61 cases of California encephalitis (CE) that occurred in Illinois between 1976 and 1980. This group represented 54% of all 114 laboratory-diagnosed cases of CE between 1966 and 1980. Key epidemiologic observations included: 88% of the 61 cases had onset in July, August, or September; the 5- to 9-year-old age group represented 48% of the cases; the male:female sex ratio was 2:1; 97% of the cases occurred in the northern half of the state; and 61% of the cases occurred in Peoria County. Four instances of probable common source of exposure were reported. Average length of hospitalization was 8.3 days (range 3-31 days). Hospitalization costs were estimated at $3,967-$5,750 per case. An "average" year in Illinois yields 12 cases of LAC encephalitis with direct hospitalization costs of $47,604-$69,000.

Adolescent↗
PubMed1983

Identification of hitherto unrecognized arboviruses from Ecuador: members of serogroups B, C, Bunyamwera, Patois, and Minatitlan.

Three hundred seventy-nine virus isolates were obtained from mosquitoes collected and sentinel hamsters exposed in coastal Ecuador from 1974 to 1978. These included four alphaviruses [Venezuelan equine encephalitis 1B (1), Venezuelan equine encephalitis 1D (35), western equine encephalitis (1) and eastern equine encephalitis (4)]; two flaviviruses [St. Louis encephalitis (3) and Naranjal (6)]; 11 bunyaviruses [Maguari (243), Playas (3), Vinces (33), Turlock (2), Abras (5), Babahoyo (3), Acara (2), Guajara (3), San Juan (6), Pueblo Viejo (3), 18 unspecified Gamboa serogroup viruses, Palestina (7)]; and one vesiculovirus (vesicular stomatitis New Jersey). All but Venezuelan equine encephalitis virus were new to Ecuador, and Naranjal (serogroup B), Playas (Bunyamwera serogroup), Vinces (serogroup C), Abras and Babahoyo (Patois serogroup), San Juan and Pueblo Viejo (Gamboa serogroup) and Palestina (Minatitlan serogroup) are newly recognized viruses. These isolates have enabled us to 1) expand our knowledge of the geographic distribution of recognized viruses, 2) expand our knowledge of the members of certain serogroups and 3) establish two new serogroups (Gamboa and Minatitlan).

Alphavirus↗
PubMed1983

Serologic evidence of arbovirus infections in humans and wild animals in Alaska.

Blood samples were collected from humans and several species of free-ranging wild animals in Alaska. Sera were tested for antibody to Jamestown Canyon (JC), snowshoe hare (SSH), Northway (NOR), Klamath (KLA), Sakhalin (SAK), Great Island (GI), and Silverwater (SIL) virus. JC antibody was found in 54% of 121 human, 89% of 97 bison (Bison bison), 51% of 84 Dall sheep (Ovis dalli), 43% of 68 snowshoe hare (Lepus americanus), and 3% of 33 arctic fox (Alopex lagopus) sera. SSH antibody was found in 42% of 121 human, 89% of 97 bison, 41% of 84 Dall sheep, and 65% of 68 snowshoe hare sera. NOR antibody was found in 14% of 121 human, 94% of 97 bison, 84% of 84 Dall sheep, 43% of 69 caribou (Rangifer tarandus), 3% of 68 snowshoe hare, 48% of 64 grizzly bear (Ursus arctos), 3% of 33 arctic fox, and 78% of 27 moose (Alces alces) sera. KLA antibody was found in 5% of 121 human and 40% of 97 bison sera. SAK antibody was found in 2% of 97 bison and 3% of 33 arctic fox sera. GI antibody was found in 1% of 97 bison sera. No SIL antibody was found in any sera tested. Thus the natural host ranges of JC, SSH, NOR, and KLA viruses have been extended by inference from the occurrence of antibody.

Alaska↗
PubMed1983

Monoclonal antibodies against the G1 and nucleocapsid proteins of LaCrosse and Tahyna viruses.

Monoclonal antibodies against the Gl (glycoprotein) and Nc (nucleocapsid) proteins of LaCrosse (LAC) and Tahyna (TAH) viruses were generated using a standard protocol. Monoclonal antibodies against Gl were either neutralizing or non-neutralizing, and there was close concordance between inhibition of hemagglutination and neutralizing activities. The LAC virus neutralizing antibodies could be further subdivided into strain-specific and cross-reactive groups on the basis of both neutralization and inhibition of hemagglutination. These data support the concept of a glycoprotein molecule with three antigenic sites, two involved in neutralization and hemagglutination, and an additional site with no biological function as yet defined. Preliminary information from LAC virus variants selected with these monoclonal antibodies agrees with this interpretation. Anti Nc antibodies were all cross-reactive in an ELISA assay. Patterns of monoclonal cross-reactivity against California serogroup viruses are compared with the currently accepted antigenic relationships.

Antibodies, Monoclonal↗