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H M Foy

Publications and source records attributed to H M Foy.

At least 37 records · Page 2Linked to original sources
PubMed1993

Infections caused by Mycoplasma pneumoniae and possible carrier state in different populations of patients.

Mycoplasma pneumoniae causes not only pneumonia but also other respiratory syndromes such as bronchitis, bronchiolitis, pharyngitis, and croup. These infections mimic viral respiratory syndromes. Most cases are treated on an outpatient basis. Epidemics take place at intervals of 4-7 years. The incidence rate is highest among school children and second highest among children < 5 years of age. Among persons who have had M. pneumoniae pneumonia, rates of subsequent infection with this organism are low, and immunity appears to increase with age. The carrier state may last for several months. Patients with humoral immunodeficiency often develop severe infections due to M. pneumoniae, with involvement of the joints; in these individuals the carrier state may persist. M. pneumoniae has been isolated from bronchial washings from children with AIDS. These children have recovered from mycoplasmal infection with appropriate antibiotic treatment. Dermatologic, neurological, cardiac, renal, and pulmonary complications occur, although data on their frequency are lacking.

Adolescent↗
PubMed1992

Seroepidemiology of Chlamydia pneumoniae TWAR infection in Seattle families, 1966-1979.

Incidence rates of Chlamydia pneumoniae infection and information on reinfection and transmission within families were obtained by serologic study of serum samples from prospective family studies conducted 1966-1979. Specimens (n = 3671) from 343 subjects in 68 families were tested for TWAR antibody using the microimmunofluorescence assay. Acute infection was defined as a fourfold rise in antibody titer between consecutive specimens. Sixty-four episodes of infection were identified in 58 persons; 4 had 2 infections and 1 had 3. From late 1975 until early 1979, when 3 serum specimens were collected yearly, rates of infection by age groups 0-4, 5-9, 10-14, 15-19, and greater than or equal to 20 years were 0, 9.2, 6.2, 2.2, and 1.5/100 person-years, respectively. Reinfections, defined as infections in persons with previous antibody, constituted most acute infections among adults. Acute infections more often affected a single family member than multiple members, but 2 or 3 family members were infected during the same period 12 times.

Adolescent↗
PubMed1990

Outbreak of anthrax in Thailand.

An outbreak of anthrax occurred among 14 persons exposed to the meat of two water buffalo which had died from anthrax, in two neighbouring villages in the northeastern region of Thailand. All but one case had typical eschars or blisters. Three had eaten raw meat; one of them died from gastric anthrax with severe haematemesis. All the others were successfully treated with penicillin. The incubation period varied between two and 11 days. Sporadic outbreaks of human and animal anthrax still occur in Southeast Asia.

Adult↗
PubMed1990

Diagnosis of Mycoplasma pneumoniae pneumonia: sensitivities and specificities of serology with lipid antigen and isolation of the organism on soy peptone medium for identification of infections.

The sensitivities and specificities of isolation and serology for detection of Mycoplasma pneumoniae infections were determined for 3,546 pneumonia patients for whom both isolation and serological data were available. Soy peptone, fresh yeast extract, horse serum-supplemented agar, and diphasic medium were employed for isolation, and the lipid antigen of M. pneumoniae was used for serodiagnosis by complement fixation. The number of M. pneumoniae colonies most frequently detected was 200 to 600 per throat swab, with a range of less than or equal to 60 to greater than or equal to 2,000. The use of diphasic medium increased the number of isolates by 26% compared with direct isolation on agar plates. The organism was isolated from 360 of 525 patients who showed fourfold or greater antibody increases in their paired sera, resulting in a sensitivity of culture of 68%. When persons with titers of greater than or equal to 32 but no fourfold increase were used as the reference, the sensitivity of culture was 58%. The combined sensitivity of the culture method for persons with serological evidence of infection (fourfold increase and titer of greater than or equal to 32) was 64%. The specificity of the culture method was 97% for the 2,527 serologically negative persons. Fourfold antibody increases were found in 360 of 674 persons with isolates of the organism, resulting in a sensitivity of 53%. An additional 247 persons showed titers of greater than or equal to 32 (without a fourfold increase), resulting in a combined sensitivity of 90% for serology with the lipid antigen for the detection of antibodies in culture-positive persons. Fourfold antibody increases were found in 6% of culture-negative persons, resulting in a specificity of 94%. The quantitative culture results provide important base-line data for the development of rapid diagnostic tests for M. pneumoniae infection.

Antibodies, Bacterial↗
PubMed1990

Epidemic of fever of unknown origin in rural Thailand, caused by influenza A (H1N1) and dengue fever.

In the late summer (rainy season) of 1987, a sharp outbreak of fever of unknown origin (FUO) in rural southern Thailand was investigated by a field epidemiology team. In a random survey of households, 40 percent of the children and 20 percent of adults were reported to have had febrile illnesses within the last month. There was at least one death, possibly from Reye's syndrome. Testing 34 pairs of acute and convalescent sera showed significant HI antibody titer rises to influenza A (Taiwan/(H1N1) (9 cases) and dengue virus (12 cases). Testing 79 single sera with the antibody capture ELISA test for dengue, revealed that 23 percent had high titers in the IgM serum fraction suggesting recent infection. There were also six antibody titer rises to coxsackie B viruses, three from well controls. Dengue has previously been observed as a cause of FUO in rural areas in the tropics, but finding a combined epidemic of dengue and influenza was unexpected. With cooperative villagers, adequate personnel and laboratory support, especially the antigen capture ELISA test for dengue infections, it is feasible to successfully investigate disease outbreaks with serologic methods in remote villages.

Chikungunya virus↗
PubMed1990

A cholera outbreak associated with eating uncooked pork in Thailand.

In a village near Chiangmai, Thailand, during October 1987, there was an outbreak of cholera following a funeral in which 264 attendants were served food. The present article is a report of an epidemiological study performed to identify the source of infection and the mode of its transmission. All the attendants were screened for infection by bacteriological examination of their rectal swabs and were kept under diarrhoeal surveillance. Of them, 20 patients and 40 matched controls were interviewed about the details of their eating foods served at the funeral. Vibrio cholerae 01, Inaba, El Tor was detected from 24 persons (9.1%), 15 of whom suffered from mild diarrhoea and the rest 9 had inapparent infections. There was no death. Except one butcher whose rectal swab was positive for the same strain of V. cholerae, 3 other butchers and 4 women who had prepared food were free from the infection. Food remnants were not available for culture. The water used for cooking and the water from the cement well used for slaughter were negative for the organism. The only significant association (p less than .01, odds ratio = 15) was found between an attack of cholera and eating laebmoo--an uncooked pork preparation with Thai spices and chili. The transmission of cholera appeared to have occurred through eating the uncooked pork presumably due to its contamination with V. cholerae shed by the infected butcher. He was known to have earlier visits to Chiangmai where cholera epidemic was going on.

Adolescent↗
PubMed1989

Several sporadic outbreaks of El Tor cholera in Sunpathong, Chiang Mai, September-October, 1987.

From September through October 1987, a cholera outbreak involving 59 cases of biotype El Tor, serotype Inaba occurred in Sunpathong district, Chiang Mai. No cases died. Twenty-seven cases were males and 32 were females. The age ranged between 4 months and 85 years, with a median of 36 years. The outbreak affected 7 small communities, and showed different vehicles of infection. Six housewives and one girl were infected with cholera in the first localized outbreak. The transmission of infection appeared due to the consumption of packed food contaminated by an infected food handler. In the second localized outbreak, 6 young males acquired cholera after eating uncooked fish harvested from a canal contaminated with cholera organisms. Another outbreak of cholera with 24 culture-confirmed cases occurred among guests at a funeral held in one rural village. The source of infection was traced to uncooked pork contaminated from an infected butcher: Early detection of infected persons, rapid identification of possible vehicles of transmission, and prompt implementation of control measures effectively curtailed the extension of these outbreaks.

Adolescent↗
PubMed1989

Epidemiology and control of dengue virus infections in Thai villages in 1987.

A severe epidemic of dengue hemorrhagic fever (DHF) in Nakhon Ratchasima, Thailand in August of 1987 prompted a field investigation. DHF rates of 0.4-6.5 cases per 1,000 residents in subdistricts and 2-15 cases per 1,000 residents in 10 villages investigated were reported. Epidemics peaked in neighboring villages at different times; in June and July, and in August before the rainy season began late in the month. In 4 primary schools representing 6 villages, sera from groups of randomly selected children were tested for dengue IgM with the antibody capture ELISA test. Rates of recent dengue infection were 10-65% in the schools and correlated closely with reported rates of DHF. In an effort to control vectors, malathion fog and temephos (1% abate sand granules) were applied. Villagers were educated in prevention and were urged to cover water receptacles. The percentage of houses with larvae dropped from 67 to 20, the percentage of containers with larvae decreased from 30 to 5, and the number of containers with larvae per 100 households decreased from 221 to 33. This was a serious epidemic in which conventional control measures were only moderately effective.

Aedes↗
PubMed1987

Influenza B in households: virus shedding without symptoms or antibody response.

In the fall of 1983, 53 households were enrolled in a double-blind trial of alpha 2-interferon as an intranasal spray to prevent common colds. During the winter/spring of 1984, 26 households were infected with influenza type B, as shown by isolation of the virus (19 households) and/or significant antibody titer rises (seven households). Interferon did not prevent influenza B infection or modify resulting illness. Of 37 persons shedding virus, 12 were asymptomatic. All were older than age 12 years, and 10 did not respond with antibody by any of the five test methods employed (complement fixation, hemagglutination inhibition, enzyme-linked immunosorbent assay (ELISA), neutralization, and Western blot). In contrast, of 13 symptomatic persons shedding virus from whom sera were available, 11 had significant antibody titer rises. Infection rates were highest among teenagers, but also surprisingly high among the 11 persons observed who were aged 50 years or older, four of whom were infected. The case-to-case interval in household transmission varied between one and nine days. Longer intervals of one, two, and four months between infections among family members were also observed, suggesting repeated introductions. Neither virus isolation alone nor serologic tests was sufficient to estimate infection rates.

Adolescent↗
PubMed1987

The principal protein antigens of isolates of Mycoplasma pneumoniae as measured by levels of immunoglobulin G in human serum are stable in strains collected over a 10-year period.

To determine whether antigenic variation in protein antigens of Mycoplasma pneumoniae occurred over time, 12 isolates obtained from pneumonia patients over a 10-year period (1964 to 1974) were compared by immunoblotting (Western blotting) against acute and convalescent human serum samples obtained from the same patients. The strains selected were isolated from patients who had low anti-lipid complement-fixing antibody titers in their acute-phase serum samples and high titers in their convalescent-phase serum samples. The polypeptide composition of the strains was closely similar by protein staining even when compared with prototype FH-Liu. On immunoblotting, all strains showed five bands (170, 130, 90, 45, and 35 kilodaltons [kDa]) which were stained more intensely by convalescent-phase than by acute-phase specimens. A sixth band (62 kDa) was detected by the conjugate alone. In FH-Liu, one band (110 kDa) was prominently stained by convalescent-phase specimens; this band was much less apparent in all of the clinical isolates. Two isolates possessed an additional band (92 kDa) which was stained more prominently by some but not all convalescent-phase specimens. Because of its known antigenic relationships and culture similarities, Mycoplasma genitalium was used for comparison. More polypeptides of M. genitalium than of M. pneumoniae were recognized by acute-phase serum samples, and 4 of 12 convalescent-phase serum samples showed increases in antibodies to certain M. genitalium polypeptides. However, these reactive polypeptides did not correspond in molecular mass to polypeptides recognized in M. pneumoniae; thus the signature profile of human convalescent-phase specimens with M. pneumoniae was distinct. These five polypeptides, individually or in combination, are especially promising for use in detection of human serum antibodies by enzyme-linked immunosorbent assay because they were found in all M. pneumoniae isolates tested.

Antibodies, Bacterial↗
PubMed1986

Rises in titers of antibody to human coronaviruses OC43 and 229E in Seattle families during 1975-1979.

Sequential serum specimens were obtained every four months during 1975-1979 from 44 children and adults of 10 Seattle families. The 419 specimens were tested for antibody to human coronaviruses OC43 and 229E by enzyme-linked immunosorbent assay (ELISA). Antibody titers were found to increase with age, and titers as well as frequency of rises were greater for OC43 than for 229E virus in all age groups. Significant antibody rises were most frequent in specimens bracketing the winter interval, but some also occurred in the spring-summer and summer-fall intervals. Concurrent significant antibody rises to OC43 virus in different members of the same family were observed in 15 instances, to 229E virus in seven instances, and to OC43 virus in some members and 229E virus in others in eight instances. Significant antibody rises to OC43 or 229E virus indicating reinfections were frequently observed throughout the three-year period but were always separated by at least two four-month intervals. Concurrent significant antibody rises to both 229E and OC43 viruses were seen only in three persons. Finally, the frequency of significant antibody rises in children, about one per person-year, was almost three times higher than in adults.

Adolescent↗
PubMed1986

Excision and grafting of large burns: operation length not related to increased morbidity.

In order to study the relation between length of operation and postoperative morbidity in patients with burns greater than 30% TBSA a retrospective review was done. Seven categories of morbidity were chosen and points assigned for significant change from the preoperative state. There were no intraoperative or immediate postoperative deaths. The overall morbidity was 19%. The eventual mortality was 19%. There was no correlation between length of operation and postoperative morbidity.

Burns↗
PubMed1986

Use of bacterial antigen detection in the diagnosis of pediatric lower respiratory tract infections.

Two immunochemical methods were used to identify Haemophilus influenzae and Streptococcus pneumoniae capsular antigens in the urine and serum of 162 children with acute lower respiratory tract infection. These methods were compared with standard bacterial blood culture. Viral and mycoplasma cultures of respiratory secretions were obtained simultaneously to determine the frequency of antigenuria at the time of nonbacterial acute lower respiratory tract infection. Urine from groups of well children and children with acute otitis media was tested for capsular antigens to determine the incidence of antigenuria. Antigenuria was found in 24% of children 2 months to 18 years of age with acute lower respiratory tract infection compared with a 2% incidence of bacteremia. Antigenuria was found in 4% of asymptomatic children and 16% of children with acute otitis media. One third of children with symptoms of acute lower respiratory tract infection and viral isolates from the oropharynx had bacterial antigenuria. The sixfold increase in frequency of bacterial antigenuria in children at the time of lower respiratory symptoms suggests that bacterial acute lower respiratory tract infection may be more common than identified by traditional culture techniques. Because bacterial antigen may come from other sites such as the middle ear, further studies are needed to determine the role of antigen detection in the diagnosis of pediatric acute lower respiratory tract infection.

Acute Disease↗
PubMed1985

Rhinoviruses in Seattle families, 1975-1979.

Rhinovirus infections in Seattle families with schoolchildren (1975-1979) and in selected outpatients were revealed by virus shedding or antibody rise. These observations extend those in the Seattle Virus Watch (1965-1969). Analysis of rhinovirus serotype prevalence again revealed certain "common" persisting serotypes but provided no further evidence that new serotypes are continuing to emerge. Two seasonal peaks, spring higher than fall, were again evident. Infection rates, again inversely related to age, were lower overall than in the Virus Watch (0.42 vs. 0.64 per person-year), probably because there were fewer young children. Frequencies of antibody response by virus shedders again varied widely by serotype but differed greatly from those in the Virus Watch in rank order of response rate, suggesting that immunogenicity is not a stable serotype characteristic. The frequency and magnitude of antibody response of virus shedders increased with age. Antibody-related protection against infection was evident only in persons age greater than or equal to 10 years. Observations in 7 families during successive homotypic infection episodes indicate that postinfection immunity to natural challenge requires persistence of antibody. Of all reported respiratory illness, 11.9% (0.31 per person-year) were due to rhinoviruses and 6.9% to influenza viruses. Of viruses recovered from family members, rhinoviruses, herpes simplex, and influenza comprised 56%, 12.6%, and 12.4%, respectively. Although households often experienced greater than or equal to 2 concurrent or closely consecutive episodes of infection with different viruses, only 29 individuals were shown to shed 2 viruses at the same time. Most of the second viruses, include 3 rhinoviruses and 18 other nonhemadsorbing viruses, appeared when 582 rhinovirus-positive specimens were retested after treatment with homotypic antibody. These results suggest that rhinoviruses interfere with nonhemadsorbing viruses in cell culture but mostly with other rhinoviruses in humans.

Adolescent↗