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F S Wignall

Publications and source records attributed to F S Wignall.

At least 37 records · Page 2Linked to original sources
PubMed1995

The impact of infectious diseases on the health of U.S. troops deployed to the Persian Gulf during operations Desert Shield and Desert Storm.

An assessment was conducted of the impact of infectious diseases on the 697,000 U.S. troops deployed to the Persian Gulf during 1990-1991 in Operations Desert Shield and Desert Storm. The incidence of nonbattle injuries, including infectious diseases, during this conflict was lower than during previous wars involving U.S. military personnel. The major reported causes of morbidity were generally mild cases of acute diarrheal and upper respiratory disease. The most unexpected outcome was the lack of arboviral infections, particularly sandfly fever, and the occurrence among U.S. troops of 12 cases of visceral leishmaniasis due to Leishmania tropica. The fact that infectious diseases were not a major cause of lost manpower, in sharp contrast to the experience among military personnel in World War II, can be attributed to a combination of factors: the presence of a comprehensive infrastructure of medical care, extensive preventive medicine efforts, and several fortuitous circumstances. Beneficial conditions that may not be present in future conflicts in this region include isolation of most combat troops to barren desert locations during the cooler, winter months, which provided the least favorable conditions for transmission of arthropod-borne diseases.

Animals↗
PubMed1995

Treatment of chloroquine-resistant Plasmodium vivax with chloroquine and primaquine or halofantrine.

Optimal therapy for infection by chloroquine-resistant Plasmodium vivax has not been established. From 1992 to 1994 during three separate studies, 147 Javanese residents of Irian Jaya infected by P. vivax were treated with either chloroquine (25 mg of base/kg during 3 days or 10 mg of base/kg in one dose) plus primaquine (10 mg/kg during 28 days or 2.5 mg/kg during 3 days) (n = 78), chloroquine plus placebo (n = 50), or halofantrine (24 mg base/kg in 12 h; n = 19). There was no difference in tolerance to or side effects of any of the regimens. Within 14 days of starting therapy, therapeutic failure among these patients was 44% for chloroquine, 5% for chloroquine plus primaquine (P < .001), and 0 for halofantrine (P < .001). After 28 days, therapeutic failure was 78%, 15%, and 6%, respectively. Thus, chloroquine plus primaquine in combination and halofantrine alone are effective therapies for chloroquine-resistant P. vivax.

Adolescent↗
PubMed1994

Natural history of HIV infection in Filipino female commercial sex workers.

A prospective follow-up study of the progression of HIV infection, from seroconversion to onset of opportunistic infections (OI) indicative of immune deficiency and to death, was performed in a cohort of 54 HIV-1 antibody positive Filipino female commercial sex workers (FCSW). The cumulative probability of having a CD4+ T cell count of < 200/mm3 and/or an OI indicative of severe immune deficiency was 52.9% within 5 years and 73.8% within 6 years after seroconversion. The cumulative probability of death was 52.1% within 6.5 years following seroconversion and 52.7% within 1.5 years after a depressed (< 200/mm3) CD4+ T cell or onset of an OI. Although several OI associated with immune impairment were observed, a CD4+ cell count of < 200/mm3 was the initial indicator of a failing immune system in more than 50% of the patients. Mycobacterium tuberculosis or unidentified acid fast bacilli (presumed to be M. tuberculosis) and Pneumocystis carinii pneumonia were the initial indicators of immune deficiency in the remaining patients.

AIDS-Related Complex↗
PubMed1993

A genotype of hepatitis D virus that occurs in northern South America.

Hepatitis D virus (HDV) is the cause of an unusually severe form of liver disease with distinct histologic features (morula cell) that occurs throughout northern South America and certain other areas of the world. Clinical studies of HDV disease worldwide indicate that there is, in fact, a wide variation in pathogenesis, and the reasons for these differences are presently unknown. One possible explanation is that factors associated with the viral genotype are determinants of HDV pathogenesis. In this study, nucleic acid sequences were determined for three different northern South American HDV isolates which were obtained from individuals with severe disease or a family history of severe disease, in areas that are hyperendemic for this disease pattern. The sequences of these three isolates are very similar to one another but only distantly related to other published HDV sequences. Comparison of the sequence of a semiconserved region from a total of 14 isolates indicates that there are at least three HDV genotypes. Most published HDV sequences, including those from North America, Europe, the Middle East, the South Pacific, and Asia, belong to a single genotype which may have some geographically based subtypes. A single Japanese isolate is the sole representative of a second HDV genotype. The South American sequences reported here constitute a third genotype. The association of a particular genotype with the severe form of type D hepatitis that occurs in northern South America supports the hypothesis that HDV genetic factors are important determinants in the pathogenesis of type D hepatitis.

Adolescent↗
PubMed1993

Three-year incidence study of retroviral and viral hepatitis transmission in a Peruvian prostitute population.

A Peruvian female prostitute population was evaluated over a 3-year period to determine the incidence and risk factors of retroviral and viral hepatitis transmission. At three survey periods, a questionnaire was administered and serum samples were obtained. A total of 966 subjects were studied, with 34% followed for 38 months, 22% followed for 18 months, and 44% evaluated just once. On initial evaluation, 3 (0.3%) had HIV-1 antibody, 170 (17.6%) had HTLV-I antibody, 578 (59.8%) had anti-HBc, and 7 (0.7%) had antibody to hepatitis C virus. The mean annual incidence of HTLV-I and hepatitis B infection was 1.6% and 4.7%, respectively. Univariate and logistic regression analysis of prevalence data indicated an association between sexual activity and HTLV-I and hepatitis B infection, but no independent risk factors were identified in cohort analysis. Parenteral risk factors were not associated with transmission, except for a small percentage of subjects who may have acquired hepatitis B infection from blood transfusions. These findings suggest that there is a high incidence of HTLV-I and hepatitis B infection from heterosexual contact in this female prostitute population.

Adult↗
PubMed1992

Seroprevalence of hepatitis C antibody in Peru.

The prevalence in Peru of antibody to hepatitis C virus (anti-HCV) was determined in a survey of populations living in the northern jungle region and in groups at high risk of parenterally and sexually transmitted diseases. All sera were initially screened for anti-HCV using commercial first and second generation ELISAs; repeatedly reactive sera were further verified with a second generation immunoblot assay. Serum samples were also tested by ELISA for HBsAg, anti-HBs, and anti-HBc. None of 2,111 sera obtained in the survey of jungle residents was positive for anti-HCV by immunoblot assay. Twelve of 16 HIV-1 antibody positive hemophiliacs, one of 103 HIV-1 antibody positive homosexuals, and three of 602 HIV-1 negative registered female prostitutes were positive for anti-HCV. A high prevalence of total markers of hepatitis B infection was found in all subjects, especially in older subjects and groups at high risk of parenterally and sexually transmitted diseases. The findings of this study indicate that seropositivity for hepatitis C virus antibody is uncommon in Peru except in high risk groups and suggest that the epidemiology of hepatitis C differs substantially from hepatitis B.

Adolescent↗
PubMed1992

Sexual transmission of human T-lymphotropic virus type I in Peruvian prostitutes.

The epidemiology of HTLV-I infection in female prostitutes was studied in a survey of 395 prostitutes from Callao, Peru (the port city of Lima), 72 prostitutes from Iquitos, Peru (another port city on the Amazon River), and 510 prenatal clinic patients from Lima. Prostitutes reported a mean of 8.8 years (range, 1-39 years) of active prostitution and a mean of 205 sexual contacts during the month prior to the study. The percentage of prostitutes with HTLV-I antibody (21.8%) was significantly higher than patients attending a prenatal clinic (3.1%; P less than .0001). The prevalence of HTLV-I antibody increased steadily with age in prostitutes, but no age trend was noted in prenatal patients. By multiple logistic regression analysis, an independent association was found between HTLV-I seropositivity and a history of prostitution in Callao, age, and positive syphilis serology when all 977 study subjects were evaluated. When prostitutes alone were analyzed, the number of years of exposure as a practicing prostitute was associated with HTLV-I seropositivity after controlling for age. These data indicate a greatly increased risk of HTLV-I infection in prostitutes in Callao, Peru, and suggest an association between sexual activity and HTLV-I transmission.

Adolescent↗
PubMed1992

In vitro antibiotic susceptibilities of Neisseria gonorrhoeae isolates in the Philippines.

Antibiotic susceptibility surveillance testing was performed on clinical isolates of Neisseria gonorrhoeae collected in September 1989 in the Philippines. beta-Lactamase was produced by 77 (55%) of 140 isolates. In vitro MIC testing revealed significant resistance to penicillin (MIC for 90% of isolates [MIC90], greater than 64 micrograms/ml), tetracycline (MIC90, 4 micrograms/ml), and cefmetazole (MIC90, 8 micrograms/ml). Spectinomycin resistance was rare (10 of 117), but the MIC90 was 32 micrograms/ml. Isolates were susceptible to fluoroquinolones and cephalosporins at the time of this survey, as evidenced by the MIC90s of ciprofloxacin (0.25 microgram/ml), norfloxacin (2.0 micrograms/ml), ofloxacin (0.625 microgram/ml), cefpodoxime (2.0 micrograms/ml), cefotaxime (1.0 microgram/ml), ceftazidime (0.25 microgram/ml), ceftizoxime (0.25 microgram/ml), and ceftriaxone (0.06 microgram/ml). To date, ceftriaxone resistance has not emerged, despite the widespread use of this antibiotic in the Philippines.

Anti-Bacterial Agents↗
PubMed1992

Antibiotic susceptibility survey of Neisseria gonorrhoeae in Thailand.

The antibiotic susceptibilities of Neisseria gonorrhoeae isolates obtained from patients attending sexually transmitted disease clinics in Cholburi and Bangkok, Thailand, were determined by agar dilution. Some 28.2% of isolates produced beta-lactamase. A total of 97.9% of beta-lactamase-positive and 51% of beta-lactamase-negative isolates tested were resistant to penicillin (MICs, greater than or equal to 2 micrograms/ml), 70% of isolates tested were resistant to tetracycline (MICs, greater than or equal to 2 micrograms/ml), and 91% of isolates tested were susceptible to spectinomycin (MICs, less than or equal to 64 micrograms/ml). The MICs for 90% of isolates for the other drugs tested were 2 micrograms/ml for erythromycin, 2 micrograms/ml for cefoxitin, 1 micrograms/ml for cefuroxime, 0.125 micrograms/ml for cefpodoxime, 0.06 micrograms/ml for cefotaxime, 0.25 micrograms/ml for ceftazidime, 0.03 micrograms/ml for ceftizoxime, 0.03 micrograms/ml for ceftriaxone, 0.03 micrograms/ml for cefixime, 0.06 micrograms/ml for aztreonam, 0.008 micrograms/ml for ciprofloxacin, 0.125 micrograms/ml for norfloxacin, and 0.075 micrograms/ml for ofloxacin. Fewer than 1.5% of isolates were resistant to the extended-spectrum cephalosporins tested. Some 0.3% or fewer isolates were resistant to broad-spectrum cephalosporins, fluoroquinolones, or the monobactam aztreonam. Antibiotic resistance among N. gonorrhoeae isolates from Cholburi and Bangkok in May 1990 appeared to be primarily limited to penicillin and tetracycline, which are no longer used to control gonorrhea. Spectinomycin, which has been in general use against gonorrhea in Thailand since 1983, has dwindling utility, with resistance at a level of 8.9%.

Anti-Bacterial Agents↗
PubMed1992

The impact of human T-lymphotrophic virus type I/II infection on the prognosis of sexually acquired cases of acquired immunodeficiency syndrome.

Twenty (18%) of 111 Peruvian men with sexually acquired human immunodeficiency virus infection were found also to be infected with human T-lymphotrophic virus type I or II in a retrospective study. At the time of data evaluation, 75 patients had reached Centers for Disease Control stage IV (clinical acquired immunodeficiency syndrome) and had not received antiviral medication; mortality in this group was 63.3% (38/60) among patients infected with human immunodeficiency virus alone and 80% (12/15) in the dually infected group. Of the 50 patients who had died, survival time from onset of stage IV to death was shorter in the dually infected group (5.02 +/- 3.27 months) than in those with human immunodeficiency virus infection alone (10.07 +/- 4.42 months). In Peru, sexually acquired human immunodeficiency virus infection in men is often accompanied by human T-lymphotrophic virus type I/II infection, and dual retrovirus infection is associated with a shorter survival after onset of clinical acquired immunodeficiency syndrome.

Acquired Immunodeficiency Syndrome↗
PubMed1992

[Outbreak of paratyphoid fever among Peruvian naval personnel].

A retrospective epidemiological study was conducted in connection with an outbreak of paratyphoid fever at a Peruvian naval installation in Callao. The study sought to determine the magnitude of the outbreak, the source of infection, the attack rates, the persistence of bacilli excretion, and the clinical picture of the disease. The source of Salmonella paratyphi B infection had been a meal of chicken and rice served to around 400 members of the naval police. Over a period of three weeks, 21 persons were hospitalized and 52 received outpatient treatment at the naval hospital. In addition, through a questionnaire it was revealed that 86 unreported cases of diarrhea related to the outbreak had occurred. The most common clinical manifestations were fever, headache, weakness, anorexia, abdominal pain, and diarrhea. The general attack rate was 39.8%. In a follow-up survey carried out 37 days after exposure, fecal cultures indicated that 8.5% of the persons affected continued to excrete the microorganism. The high rates of attack and transmission of S. paratyphi B in this outbreak point up the considerable pathogenicity and virulence of some strains of the microorganism and their impact on public health. It is suggested that preventive measures be taken at naval and other similar installations, including the education of workers who handle and prepare food, in order to ensure proper hygiene.

Adult↗
PubMed1990

Efficacy and toxicity of sodium stibogluconate for mucosal leishmaniasis.

OBJECTIVE: To determine the efficacy and toxicity of the World Health Organization's (WHO) recommended treatment for mucosal leishmaniasis: antimony, 20 mg/kg body weight per day for 28 days. DESIGN: Open trial with 12-month follow-up. SETTING: Inpatient unit of a regional referral hospital in a developing country. PATIENTS: Twenty-nine consecutive eligible patients with culture-confirmed infection of the mucosa with Leishmania species who were otherwise healthy. Eight patients (28%) had mild to moderate disease (confined to the nasal mucosa). Twenty-one patients (72%) had severe disease (including the oropharynx as well as the nasal mucosa). INTERVENTION: Antimony, 20 mg/kg body weight intravenously every day for 28 days. Patients received antimony in the form of sodium stibogluconate. MEASUREMENTS AND MAIN RESULTS: Initial results of therapy were as follows: 63 of 72 lesions (88%) healed or markedly improved; all lesions were culture-negative for parasites; and 18 of 29 patients (62%) showed complete clinical and parasitologic cure of all lesions. By the 12-month follow-up examinations, however, 37 lesions had recurred, 8 new lesions had appeared, and only 8 patients (30%) showed clinical cure of all lesions. Of the 8 patients with mild to moderate disease, 6 were cured compared with only 2 of the 21 patients with severe disease. Side effects of this treatment regimen included T-wave inversion on electrocardiogram (4 patients), abnormal liver function tests (10 patients), and musculoskeletal pain (24 patients). No side effects occurred during week 1 of therapy. CONCLUSIONS: The only recommended treatment for mucosal leishmaniasis is ineffective in patients with severe disease. The acceptable toxicity of the regimen suggests that longer courses of therapy with antimony, or that trials with other antileishmanial agents alone or combined with antimony be evaluated as initial therapy for this disease.

Adult↗
PubMed1990

Hepatitis B in a highly active prostitute population: evidence for a low risk of chronic antigenemia.

The epidemiology of hepatitis B in female prostitutes was studied in a cross-sectional survey of 467 prostitutes and 510 control prenatal clinic patients from Lima and Iquitos, Peru. Prostitutes reported a mean of 8.8 +/- 6.7 years of active prostitution and a mean of 205 +/- 137 sexual contacts in the month prior to the study. Hepatitis B surface antigen (HBsAg) was found in comparable percentages of prostitutes (1.7%) and controls (0.8%; P = .305). In contrast, seropositivity for both antigen and antibody markers (HBsAg, anti-HBs, or anti-hepatitis B core) was found in a significantly higher percentage of prostitutes than controls (67.0% vs. 10.0%; P less than .0001). By multivariate analysis, both prostitution (odds ratio [OR] 14.6) and the number of years of exposure as a prostitute (OR 3.2 for 10 years of exposure at age 35 years) were significantly associated with seropositivity for hepatitis B markers when adjusted for age. In this study, the prevalence of HBsAg was not substantially increased in highly active female prostitutes compared with the general population, even though hepatitis B transmission was greatly increased. These data suggest that in adult women with a high level of hepatitis B infection, hepatitis B antigenemia may not persist as frequently as previously indicated in studies of other populations.

Adult↗
PubMed1990

An epidemic of Oroya fever in the Peruvian Andes.

Between February and October 1987, a febrile illness killed 14 persons and seriously affected at least 14 others in Shumpillan, a remote Peruvian mountain village of 353 people. The illness was characterized by fever, headache, chills, and pallor. The fatality rate of untreated cases was 88%. The patients, 71% of whom were male, were 1-75 years of age. Fatal illnesses progressed from lethargy to coma to death in 3-60 days. Patients treated empirically with chloramphenicol survived. Bartonella bacilliformis was isolated from the whole blood of 3 patients. A serologic study revealed a high prevalence of antibodies to B. bacilliformis in the villagers. It is concluded that the villagers suffered from an epidemic of Oroya fever.

Adolescent↗
PubMed1990

Diffuse cutaneous leishmaniasis acquired in Peru.

A case of diffuse cutaneous leishmaniasis (DCL) acquired in Peru is described. The causative agent was Leishmania mexicana amazonensis as determined by isoenzyme analysis and species-specific monoclonal antibody binding characteristics. Histological examination of biopsy material showed a large number of intracellular and extracellular amastigotes and few lymphocytes. Treatment with meglumine antimoniate (Glucantime) administered iv at a dosage of 20 mg antimony/kg body weight/day for 60 days resulted in visible improvement of the lesions, but not in clinical or parasitological cure.

Adult↗
PubMed1988

Nontoxigenic 01 Vibrio cholerae in Peru: a report of two cases associated with diarrhea.

Two 01 Vibrio cholerae, E1 Tor strains, serogroup Ogawa were isolated from diarrheal stool material of two North American males residing or visiting in Peru. No other enteric pathogens were found. These strains did not produce cholera toxin as detected by enzyme-linked immunosorbent and Y1 adrenal cell assays, nor did they hybridize with an oligonucleotide probe for heat-labile (LT) toxin of Escherichia coli. These two cases are the first reports of 01 V. cholerae isolated from clinical specimens in South America.

Adult↗