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C H Calisher

Publications and source records attributed to C H Calisher.

At least 91 records · Page 5Linked to original sources
PubMed1986

Complex-specific immunoglobulin M antibody patterns in humans infected with alphaviruses.

Sera from humans with serologically confirmed eastern equine encephalitis, western equine encephalitis, Pogosta (Ockelbo), Mayaro, Ross River, and chikungunya virus infections were tested by immunoglobulin M (IgM) antibody capture enzyme immunoassay. Diagnostically useful IgM antibody titers were detected, and selected sera with high IgM antibody titers were tested for IgM antibody with nine heterologous alphaviruses. The results provide evidence for the complex specificity of IgM antibody and indicate the usefulness of this test in both individual cases and epidemic situations.

Alphavirus↗
PubMed1986

Specificity of immunoglobulin M and G antibody responses in humans infected with eastern and western equine encephalitis viruses: application to rapid serodiagnosis.

Paired sera from 20 humans with eastern equine encephalitis (EEE) virus infections and from 17 humans with western equine encephalitis (WEE) virus infections, all with previously demonstrated fourfold or greater rises or falls in hemagglutination-inhibiting, complement-fixing, or neutralizing antibody titers, were tested for immunoglobulin M (IgM) and IgG antibodies by an enzyme immunoassay. All individuals with EEE and 14 of 17 individuals with WEE had IgM antibody, some as early as 1 day after onset. Two of the three persons with WEE who did not develop IgM antibody died. IgM antibody declined but persisted for at least 3 months after the onset of illness in one individual each with EEE and WEE. IgG antibody was not detected until the middle of week 2 after onset. The sensitivity of the IgM antibody capture enzyme immunoassay described and the specificity, as shown by the absence of heterologous alphavirus reactivity, indicate that this is the test of choice for the rapid diagnosis of human infections caused by EEE and WEE viruses.

Adolescent↗
PubMed1986

Serodiagnosis of La Crosse virus infections in humans by detection of immunoglobulin M class antibodies.

Sera from 92 humans with illnesses clinically compatible with those caused by California serogroup virus infections were tested for antibody to La Crosse (LAC) virus by using the immunoglobulin M (IgM) antibody-capture enzyme-linked immunosorbent assay (MAC ELISA), the IgG ELISA, and the hemagglutination inhibition (HI), complement fixation and serum dilution-plaque reduction neutralization tests. On the reported day of onset of illness in 18 individuals, 94% had IgM antibody, 50% had neutralization antibody, 33% had HI antibody, and 11% had IgG antibody. Neutralization, HI, and IgG antibody prevalence rates increased thereafter, whereas IgM antibody prevalence remained high (92% 2 or more weeks after the onset of illness). It was concluded that the MAC ELISA is a sensitive test for the presence of antibody to LAC virus. The sensitivity of the MAC ELISA and the rapidity with which it can be performed appear to provide a powerful tool for the clinically relevant serodiagnosis of LAC virus infections in humans.

Adolescent↗
PubMed1986

Relevance of detection of immunoglobulin M antibody response in birds used for arbovirus surveillance.

Young chickens were inoculated with 5,000 PFU of eastern equine encephalitis (EEE) virus and bled at intervals thereafter for determinations of hemagglutination-inhibiting (HI), neutralizing (N), immunoglobulin M (IgM), and IgG antibodies. HI, N, and IgM antibodies were first detected 4 days after infection, and IgG was detected 7 days after infection. All four antibodies persisted through day 90 after infection. HI, N, and IgM antibody titers remained elevated and were not cross-reactive with the related alphavirus western equine encephalitis (WEE) virus. IgG antibody titers also remained high, but heterologous reactivity to WEE virus increased with time after infection. Serum samples from sentinel chickens and wild birds infected in nature with EEE, WEE, or St. Louis encephalitis virus and submitted to this laboratory from state and local health departments were tested for IgM antibody by using anti-chicken IgM for capture and for IgG antibodies to the EEE and WEE viruses. There was essentially complete correlation between HI, N, and either IgM (indicating recent infections) or IgG (indicating more remote infections) antibody. We conclude that the IgM antibody capture enzyme immunoassay can be used as a specific and sensitive assay to replace the routinely used HI test for detecting antibody in sentinel chickens and in young, wild birds used for arbovirus surveillance. The test is rapid and relatively inexpensive and can be performed in essentially all adequately supplied laboratories.

Alphavirus↗
PubMed1986

Jamestown Canyon virus (California serogroup) is the etiologic agent of widespread infection in Michigan humans.

In a sample population of 780 Michigan residents tested for neutralizing antibodies to California serogroup viruses, 216 (27.7%) had specific neutralizing antibody to Jamestown Canyon virus. An additional eight (1.0%) had specific neutralizing to trivittatus virus; none had specific neutralizing antibody to La Crosse virus. Significantly more male residents than female residents of the Lower Peninsula had antibody to Jamestown Canyon virus. The frequency of neutralizing antibody titers fits the Poisson distribution, suggesting that Jamestown Canyon virus infections occur endemically in residents of Michigan. Among 128 sera with specific neutralizing antibody to Jamestown Canyon virus, only two (1.6%) were found to have significant hemagglutination-inhibiting antibody titers with La Crosse virus, while 23 of 44 (52%) had significant titers with Jamestown Canyon virus; a single serum had significant antibody by complement fixation tests with both La Crosse and Jamestown Canyon viruses. This study confirms earlier speculation that complement fixation and hemagglutination-inhibition tests with La Crosse virus (the only tests for California serogroup virus infections performed by most state diagnostic laboratories) fail to detect antibody to Jamestown Canyon virus. ASPEX computer-drawn maps demonstrated that the distribution of persons with antibody to Jamestown Canyon virus and residing in Michigan's Lower Peninsula is closely correlated with the estimated distribution of white-tailed deer in that part of the state, further supporting the hypothesis that white-tailed deer are the primary vertebrate host for Jamestown Canyon virus.

Adolescent↗
PubMed1986

Distribution of Bunyamwera serogroup viruses in North America, 1956-1984.

We attempted to tabulate all Bunyamwera serogroup (family Bunyaviridae, genus Bunyavirus) isolates from North America. By summarizing information from the laboratories of the Centers for Disease Control, data generously shared by other laboratories, and the published literature, we were able to accumulate data regarding 1,372 Bunyamwera serogroup viruses. These were: Tensaw (664, including 8 from vertebrates), Cache Valley (396, including 6 from vertebrates), Main Drain (160, including 14 from vertebrates), Lokern (69, including 8 from vertebrates), Northway (13, including 5 from vertebrates), Tlacotalpan (7), Santa Rosa (2), Santa Cruz (1 from a horse), and 60 of undetermined serotype. Virus isolation rates by month of collection were correlated with collection efforts, but associations of viruses and arthropod vectors varied by location, vertebrate host, and arthropod distribution. Tensaw virus was isolated principally from Anopheles crucians mosquitoes (466/656 isolates from arthropods) in the southeastern United States; Cache Valley virus principally from An. quadrimaculatus (94), Coquillettidia perturbans (59), Culiseta inornata (45), Aedes sollicitans (30), Psorophora columbiae (23), An. punctipennis (18), and Ae. vexans and trivittatus (18 each) mosquitoes (total = 305/382 isolates from arthropods from all of the United States and Canada, except the southeastern United States); Main Drain virus from Culicoides variipennis (31), Culicoides (Selfia) sp. (65), and Psorophora (23) and Aedes (21) species mosquitoes in the western United States; Lokern virus from Culicoides species (55/61 isolates from arthropods) in the western United States. Relationships between vector and vertebrate host distributions are discussed briefly in regard to geographic distribution of the Bunyamwera serogroup viruses.

Aedes↗
PubMed1986

Identification of Aedes campestris from New Mexico: with notes on the isolation of western equine encephalitis and other arboviruses.

An arbovirus survey was conducted during August 1985 at White Sands Missile Range in southcentral New Mexico following a suspected arboviral disease epizootic among feral horses. A total of 20,566 mosquitoes (18,505 females and 2,061 males) and 8,900 biting gnats were collected and assayed for virus. Female mosquitoes were principally Aedes campestris (54.8%), Aedes dorsalis (30.4%) and Culex tarsalis (13.2%). Arboviruses were not isolated from biting gnats, but mosquitoes yielded a total of 37 viral isolates, including western equine encephalitis (WEE) (18), California serogroup (15), Cache Valey (1), and Hart Park (1) viruses in addition to 2, as yet unidentified, rhabdoviruses. Isolates of WEE virus were from 9 pools of Ae. campestris, 6 of Cx. tarsalis and 3 of Ae. dorsalis. California serogroup viruses, including 2 subtypes, were obtained from 7 pools of females and 1 pool of males of Ae. campestris and from 4 pools of Ae. dorsalis. Cache Valley and Hart Park viruses were isolated from single pools of Ae. dorsalis and Cx. tarsalis, respectively, and the rhabdoviruses were obtained from Ae. campestris and Psorophora signipennis.

Aedes↗
PubMed1986

Rapid and specific serodiagnosis of western equine encephalitis virus infection in horses.

Paired sera from 28 nonvaccinated horses with serologically confirmed western equine encephalitis (WEE) virus infections were evaluated for immunoglobulin (Ig)M and IgG directed against WEE virus, by use of enzyme immunoassay. Twenty-one of the horses developed greater than or equal to 4-fold increases or decreases in serum IgM titers in paired serum samples, confirming the diagnosis of WEE in these horses. Of the remaining 7 horses, 1 had stable IgM titers, 1 had a 2-fold increase in IgM titer between paired sera, 2 had 2-fold decreases in IgM titer, and for 3 horses adequate volumes were not available for both sera of the pair. Twenty-nine of 56 blood samples collected from these 28 horses had been collected within the first 3 days after clinical disease was recognized; all 28 horses and 48 of 53 available serum samples had IgM antibody to WEE virus. Immunoglobulin M also was detected in sera of 27 of 45 other nonvaccinated horses that had illnesses clinically compatible with WEE. Sera with IgM did not have cross-reacting IgM against eastern equine encephalitis virus. Therefore, the sensitivity, specificity, and lack of persistence of IgM was useful in the rapid diagnosis of WEE virus infections in horses.

Animals↗
PubMed1985

Sindbis virus isolations from Saudi Arabian mosquitoes.

A study in late 1979 to early 1980 was conducted to assess arbovirus activity in the Eastern Province of Saudi Arabia. From 38,245 mosquitoes collected at 3 locations, 16 isolations of Sindbis virus were made: 13 from Culex univittatus and one each from Cx tritaeniorhynchus, Cx pipiens complex, and Culex spp. These isolations represent the first records of a mosquito-borne virus from the Gulf of Arabia and implicate Cx univittatus as the principal vector. A potential risk of human diseases exists due to Sindbis virus in Saudi Arabia.

Animals↗
PubMed1985

Diagnosis of Colorado tick fever virus infection by enzyme immunoassays for immunoglobulin M and G antibodies.

An immunoglobulin M (IgM) capture enzyme immunoassay technique was adapted for the detection of antibody to Colorado tick fever virus in sera from 84 individuals for whom diagnosis had been confirmed by virus isolation or neutralization test. Titers were compared with those for IgG and neutralizing antibodies in these Colorado tick fever cases. IgM antibody titers were higher than neutralizing antibody titers, but neither appeared until 1 to 2 weeks after the onset of illness. Neutralizing antibodies were detected earlier than IgM antibodies, and both were detected with greater frequency than IgG antibodies. Late-convalescent-phase sera contained both neutralizing and IgG antibodies, but IgM was all but undetectable by 2 months after onset. Although the neutralization test may remain the serological test of choice, the enzyme immunoassay for IgM antibody offers a simple and more rapid method of serodiagnosis; the enzyme immunoassay is, however, less sensitive than the neutralization test. Furthermore, because there was a sharp decline in IgM antibody after 45 days, the presence of IgM antibody in a single serum sample provides a basis for the presumptive serodiagnosis of recent Colorado tick fever virus infection.

Adolescent↗
PubMed1985

Sensitive enzyme immunoassay for detecting immunoglobulin M antibodies to Sindbis virus and further evidence that Pogosta disease is caused by a western equine encephalitis complex virus.

An antibody capture enzyme immunoassay (EIA) was adapted for the detection of immunoglobulin M (IgM) antibody to Sindbis (SIN) virus. Sera from humans with a febrile illness characterized by rash and arthralgia in eastern Finland (Pogosta [POG] disease) and Sweden (Ockelbo disease) and from humans with western equine encephalitis (WEE) virus infection in the United States were tested for IgM antibodies by EIA. Seroconversions were documented in patients with POG disease and with WEE virus infections by using SIN virus as antigen and rabbit anti-SIN virus immunoglobulin; this confirms previous observations that POG disease is caused by a virus closely related to SIN virus and that IgM antibodies to WEE complex alphaviruses are not type specific. This IgM EIA provided a sensitive diagnostic and research tool applicable to epidemiologic problems posed by POG disease.

Antibodies, Viral↗
PubMed1985

Investigations of the vertebrate hosts of eastern equine encephalitis during an epizootic in Michigan, 1980.

A study was undertaken to investigate an increase in reported cases of clinical encephalitis due to eastern equine encephalitis (EEE) virus in horses and to determine the natural vertebrate hosts of that virus. Horses, birds, and small mammals were sampled at sites in a contiguous area in St. Joseph and Kalamazoo counties, Michigan, from 25 August to 5 September 1980. Serum samples from four horses acutely ill with encephalitis and 16 of 39 pasture mates of ill horses had neutralizing (N) antibody against EEE virus (46.5%); no viruses were isolated from these 43 sera. None of 24 draft horses from a site in St. Joseph County 12 km southeast of the affected sites had EEE antibody. A strain of Cache Valley virus was isolated from the blood of one of the 24 draft horses. No viruses were isolated, and no antibodies to EEE virus were detected in 28 blood samples from small mammals captured at sites where equine cases of encephalitis were occurring. Six strains of EEE virus, five of Highlands J virus, and one of Flanders virus were isolated from the blood of 401 wild birds belonging to 42 species captured at eight sites in both counties. A total of 29.9% of the wild birds had EEE antibody. Five species of domestic birds, mostly chickens and ring-necked pheasants, were sampled in both counties. Six strains of EEE virus were isolated from 152 ring-necked pheasants; these included three isolates from the brains of dead birds. About 13% of 51 pheasants tested from two small flocks in backyard pens in Kalamazoo County and 9% of 103 pheasants tested from a large game farm in St. Joseph County had antibody to EEE virus. The source of the EEE virus and the factors responsible for this epizootic are unknown; however, the epizootic probably represented an explosive expansion of an enzootic level of virus transmission.

Alphavirus↗
PubMed1985

Arbovirus investigations in Argentina, 1977-1980. II. Arthropod collections and virus isolations from Argentine mosquitoes.

Prospective surveys for arboviruses were carried out in Santa Fe, Corrientes, and Chaco provinces, Argentina, aperiodically during 1977-1980. A total of 313,233 mosquitoes and 598 biting flies other than mosquitoes were collected and tested for virus in 5,197 and 45 pools, respectively. Forty virus strains were isolated, all from mosquitoes, as follows: Santa Fe Province: 4 Gamboa group viruses from Aedeomyia squamipennis, 1 strain each of St. Louis encephalitis virus from Culex pipiens quinquefasciatus and Culex (Culex) spp.; Corrientes Province: a single strain of a newly discovered Anopheles A serogroup virus, Las Maloyas, from Anopheles albitarsis; and Chaco Province: 4 Gamboa group viruses from Ad. squamipennis, 6 strains of new Bunyaviridae (1 Antequera, 1 Barranqueras, and 4 Resistencia) from Culex (Melanoconion) delpontei, 3 strains of a new subtype of western equine encephalitis virus and 1 strain of Para virus from the Cx. (Mel.) ocossa group, 12 strains of a newly discovered subtype (VI) of the Venezuelan equine encephalitis complex from Cx. (Mel.) delpontei, and 1 strain each from Ad. squamipennis, Aedes scapularis, Ae. spp., Cx. (Cux.) spp., Cx. (Mel.) ocossa group, Mansonia spp., and Psorophora spp. Bloodmeals from 265 engorged mosquitoes were identified by precipitin test. These data, coupled with data on engorgement rates for 25,995 mosquitoes from bait collections, provide information on the host feeding patterns of several mosquito species. This information is discussed, along with data on relative abundance of mosquito species, within the context of the vector relationships of the species from which viruses were isolated. The association of Cx. (Mel.) delpontei with 18 strains of 4 different viruses in Chaco Province, plus its catholic feeding habits, clearly indicate for the first time the importance of this species as an arbovirus vector.

Aedes↗
PubMed1985

Arbovirus investigations in Argentina, 1977-1980. III. Identification and characterization of viruses isolated, including new subtypes of western and Venezuelan equine encephalitis viruses and four new bunyaviruses (Las Maloyas, Resistencia, Barranqueras, and Antequera).

Forty viruses isolated from mosquitoes between 1977 and 1980 in Argentina have been identified and characterized. Nineteen strains of VEE virus, identical by neutralization (N) tests, were shown by hemagglutination-inhibition tests with anti-E2 glycoprotein sera to represent a new subtype VI of the VEE complex. RNA oligonucleotide fingerprints of this virus were distinct from subtype I viruses. The virus was not lethal for English short-haired guinea pigs, indicating that it is probably not equine-virulent. Three strains of a member of the WEE virus complex were shown to differ by N tests in 1 direction from prototype WEE virus. The new WEE subtype was also found to be distinct by RNA oligonucleotide mapping. Its vector relationships indicate that it is an enzootic virus, and it has not been associated with equine disease. A new member of the Anopheles A serogroup was identified, shown to be most closely related to Lukuni and Col An 57389 viruses, and given the name Las Maloyas virus. A strain of Para virus (Bunyaviridae, Bunyavirus) was identified. Six isolates, representing 3 new viruses morphologically resembling bunyaviruses are described; the names Antequera, Barranqueras, and Resistencia are proposed for these agents, which were all isolated from Culex (Melanoconion) delpontei in Chaco Province. No serologic relationships between these viruses and other bunyaviruses were found. Since they are antigenically interrelated, they form a new (Antequera) serogroup. Eight Gamboa serogroup viruses and 2 strains of St. Louis encephalitis virus were also identified.

Aedes↗
PubMed1985

Antibodies to Congo-Crimean haemorrhagic fever, Dhori, Thogoto and Bhanja viruses in southern Portugal.

Dhori and Thogoto viruses have been isolated from ticks in Portugal. In this country favourable ecologic conditions exist for other tick-borne viruses such as Bhanja and Congo-Crimean haemorrhagic fever (C-CHF) viruses. A serological survey for antibodies to these 4 tick-borne viruses in 258 human and 141 goat sera was done using the plaque reduction neutralization (PRN) and indirect fluorescent antibody (IFA) tests. Six human sera were found with antibodies to Dhori (2), Thogoto (2) and C-CHF (2) viruses, while seven goat sera had neutralizing antibodies (NA) to Dhori (5) or Bhanja (2) virus. From these results it seems likely that Bhanja and C-CHF, not yet isolated in Portugal, may exist focally in certain areas of southern Portugal.

Adolescent↗