RESUMO
PIP: While Honduras is home to only 15% of Central America's population, it has 60% of the region's AIDS cases. There have been 4973 reported cases of full-blown AIDS in the country and the Health Ministry reports that more than 8000 Hondurans have been infected with HIV since the first Honduran case was diagnosed in 1985. 995 people with AIDS have since died. The authors conducted an investigation to determine which HIV-1 subtype is present in Honduras and the degree of genetic variation among HIV-1 strains by analyzing viral nucleotide sequences from the envelope region of HIV-1 isolates obtained from the two most affected regions of the country. They determined the predominant HIV-1 subtype among 27 HIV-1-infected patients attending sexually transmitted disease clinics in San Pedro Sula and Tegucigalpa by sequencing and analyzing the C2V3 regions of the envelope glycoprotein gp 120. Genomic DNA was isolated from patients' peripheral blood mononuclear cells. Phylogenetic analysis determined that all 27 Honduran sequences clustered with known subtype B sequences.^ieng
Assuntos
Proteína gp120 do Envelope de HIV/genética , Infecções por HIV/epidemiologia , HIV-1/genética , Sequência de Aminoácidos , Honduras/epidemiologia , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Peptídeos/genética , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de AminoácidosRESUMO
OBJECTIVE: To determine the ability of simple, rapid tests to identify HIV-1 antibody-positive specimens in field settings using the World Health Organization's (WHO) alternative testing strategies. DESIGN: Three-phase evaluation of simple, rapid assays using banked specimens and prospectively collected serum specimens at regional hospitals and rural clinics. METHODS: Seven test (Retrocell, Genie, HIVCHEK, SUDS HIV-1, Testpack, Serodia HIV-1, and HIV-1/2 RTD) were evaluated and results compared with standard enzyme immunoassay (EIA) and Western blot results (phase 1). Further evaluation consisted of prospective testing of routine specimens at regional (phase 2; n = 900) and rural, peripheral laboratories (phase 3; n = 1266) throughout Honduras with selected assays. RESULTS: Sensitivity and specificity were calculated for each assay and combination of assays for each phase to evaluate the effectiveness of the WHO alternative testing strategies. All tests in all phases were > 99% sensitive after correcting for technical errors, with two exceptions (SUDS, phase 1; HIVCHEK, phase 3). In phase 3, where the testing algorithm was diagnostic, several combinations of assays were 100% sensitive and specific using WHO strategy II or III. For the Honduras Ministry of Health, the combination of Retrocell and Genie was found to be equally sensitive, more specific (no indeterminate results), and less expensive than EIA/Western blot. CONCLUSION: Combinations of rapid, simple HIV antibody assays provide sensitivity and specificity performance comparable to EIA/Western blot. Application of these combinations in the WHO alternative testing strategies provides an inexpensive and effective method of determining HIV status. Assay combinations using these strategies can be easily performed in small, rural laboratories and have been implemented in routine HIV screening in Honduras.
PIP: In 1992, the World Health Organization (WHO) introduced 3 HIV testing algorithms designed to provide rapid, accurate results equivalent to those obtained by enzyme immunoassay (EIA) and Western blot but at reduced costs. The capability of the WHO strategy to identify HIV-1 antibodies in field settings was evaluated at regional hospitals and rural clinics in Honduras. In the study's first phase, the results of 7 tests (Retrocell, Genie, HIVCHEK, SUDS HIV-1, Testpack, Serodia HIV-1, and HIV-1/2 RTD) were compared with results for 600 sera previously tested by EIA and Western blot. Phase 2 entailed prospective testing of 900 routine specimens at regional laboratories, while phase 3 screened 1266 specimens at rural, peripheral laboratories. In the first phase of the analysis, 5 assays had a sensitivity of 100%; the remaining 2 were 99.7% and 99.3% sensitive and specificities ranged from 92.8 to 100%. In field settings, sensitivities ranged from 96.4 to 99.3%. Moreover, in the third phase, several combinations of tests were 100% sensitive or specific when the WHO strategy of basing the choice of assay on the purpose of the screening (seroprevalence studies, screening of blood, or patient diagnosis) was employed. The combination of Retrocell and Genie was found to be equally sensitive, more specific, and less expensive than EIA or Western blot.
Assuntos
Sorodiagnóstico da AIDS/métodos , Infecções por HIV/diagnóstico , HIV-1 , Anticorpos Anti-HIV/análise , Infecções por HIV/epidemiologia , HIV-1/imunologia , Honduras/epidemiologia , Humanos , Técnicas Imunoenzimáticas , Programas de Rastreamento , Kit de Reagentes para Diagnóstico , Organização Mundial da SaúdeRESUMO
In early December 1989, an outbreak that was initially thought to be scabies was investigated among employees of tourist hotels in Cozumel, Mexico. Of 417 employees interviewed, only 19 (4.6%) met a case definition for scabies dermatitis, while 91 (21.8%) reported a nonspecific dermatitis of less than one-week's duration. Persons with nonspecific dermatitis related the onset of their dermatitis to skin contact with a moth that had been present in large numbers in November. At the time of the initial investigation in December, there were no active cases of dermatitis and the moth was no longer present. During early January 1990, numerous cases of dermatitis again began to be reported. Using a case definition for nonspecific dermatitis, a survey of Cozumel's resident population showed an attack rate of 12.1%. A case-control study revealed the only significant risk factor to be skin contact with the suspect moth (P less than 0.01), which had returned in large numbers. Six health workers volunteered to have the moth rubbed on their skin; within 5 min, five of six developed an intense pruritus followed by an erythematous rash. The moth was classified as Hylesia alinda Druce. This species has nettling hairs on its abdomen that excrete a histamine-like substance. Although this moth is normally present in small numbers in Cozumel, the passage of hurricane Gilbert killed most of its natural predators (wasps and bees), allowing its population to overgrow. No control measures were undertaken because the moth's natural predators returned that spring and dramatically reduced the moth population. No further outbreaks of dermatitis occurred.
Assuntos
Dermatite de Contato/etiologia , Surtos de Doenças , Mariposas/imunologia , Adolescente , Adulto , Animais , Estudos de Casos e Controles , Criança , Pré-Escolar , Dermatite de Contato/epidemiologia , Feminino , Humanos , Masculino , México/epidemiologia , Fatores de RiscoRESUMO
A case-control study of mortality from acute respiratory infections (ARI) among children under five years of age was conducted in Naucalpan, an urban-suburban area of Mexico City, and in rural localities of Tlaxcala, Mexico. The study found that ARI deaths tended to occur in the poorest neighborhoods; 78% of the deceased study subjects were infants under six months old; and 68% of the deaths occurred at home. Comparison of the data for cases (fatalities) and control children who had severe ARI but recovered showed that failure to receive antibiotics was associated with death (odds ratio 28.5, 95% confidence interval 2.1-393.4). This antibiotic effect was controlled for numerous potentially confounding factors. It is evident that antibiotics had a much greater effect in the early days of the illness than later on. In general, the findings strongly support PAHO/WHO primary health care strategies--including such strategies as standardized management of severe ARI cases--that seek to reduce childhood ARI mortality.
Assuntos
Antibacterianos/uso terapêutico , Infecções Respiratórias/mortalidade , Antibacterianos/administração & dosagem , Estudos de Casos e Controles , Pré-Escolar , Fatores de Confusão Epidemiológicos , Humanos , Lactente , Análise por Pareamento , México/epidemiologia , Infecções Respiratórias/tratamento farmacológico , Fatores de Risco , População Suburbana , População UrbanaRESUMO
PIP: Physicians investigated a nosocomial diarrhea outbreak among 11 2 year old undernourished children in the nutrition service of the pediatric teaching hospital, Hospital Infantile, in Mexico City, Mexico in April 1988. Health practitioners took at least 2 stool samples from each ill child to be analyzed for Cryptosporidium oocysts. The attack rate stood st 82%. The hospital admitted a malnourished child with chronic diarrhea and pneumonia on March 22. Laboratory tests revealed that he had many Cryptosporidium oocysts and was positive for HIV. Hospital staff did not isolate him. He died on May 9 of Escherichia coli and Candida septicemia. The outbreak ended 1 week later. Laboratory tests detected Cryptosporidium oocysts in 9 cases all of whom were 3-13 months old. Further the symptoms (mean duration 14 days, fever [mean peak 38.6 degrees Celsius, and vomiting] matched those of other reported Cryptosporidium diarrhea outbreaks. The epidemic curve suggested a common source of the outbreak. Since the infants received intravenous feedings or sterilized formula, food and water could not have been the source. The physicians believed the AIDS case was that source. Direct person to person transmission was probably not responsible since each infant had his/her own separate crib. Even though the physicians could not conclusively identify the vehicle of transmission, it was most likely the hands of hospitals staff either directly by touching the infants or by contaminating the nasogastric tubes. After the outbreak, the physicians observed that only 30% of medical personnel indeed washed their hands before caring for an infant. 4 previous studies on nosocomial Cryptosporidium diarrhea outbreaks also reported the source case as immunodeficient, but these studies only included adults.^ieng
Assuntos
Infecção Hospitalar/parasitologia , Criptosporidiose/epidemiologia , Diarreia Infantil/parasitologia , Surtos de Doenças , Síndrome da Imunodeficiência Adquirida/parasitologia , Infecção Hospitalar/epidemiologia , Hospitais Pediátricos , Humanos , Lactente , México/epidemiologiaRESUMO
Outbreaks of acute hepatitis occurred in Huitzililla and Telixtac, two rural villages 70 miles south of Mexico City, Mexico, in late 1986. The first outbreak began in Huitzililla in June of that year, 1 month after the start of the rainy season. A census revealed 94 icteric case subjects, for an attack rate of 5%; two women died. Attack rates were higher for persons older than 15 years (10%) than for younger persons. A case-control study showed that illness was highly associated with water-related factors. The second outbreak began in August 1986 in Telixtac. There were 129 case subjects, for an attack rate of 6%; one woman died. Epidemiologic findings were similar to those in Huitzililla, except that most disease transmission was not linked to unsafe water sources. None of 62 case subjects in Huitzililla and only 2 of 53 case subjects in Telixtac tested had serological evidence for recent infection with hepatitis A or B. Two of eight stool samples from Huitzililla and one of the eight stool samples from Telixtac were positive by immune electron microscopy for 32- to 34-nm viruslike particles similar to those seen in cases of enterically transmitted non-A, non-B hepatitis from Asia. To our knowledge, these investigations document for the first time the epidemic transmission of enterically transmitted non-A, non-B hepatitis virus in the Americas.
Assuntos
Surtos de Doenças , Hepatite C/transmissão , Hepatite Viral Humana/transmissão , Doença Aguda , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Surtos de Doenças/estatística & dados numéricos , Família , Fezes/microbiologia , Feminino , Seguimentos , Anticorpos Anti-Hepatite/análise , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Vírus de Hepatite/ultraestrutura , Humanos , México/epidemiologia , Razão de Chances , Gravidez , População Rural , Estações do Ano , Microbiologia da ÁguaRESUMO
Screening of blood product donations for antibody to HIV began in Mexico in May 1986. From June to October 1986, the HIV cumulative seroprevalence increased from 6.3 to 9.2% in a commercial plasma collection center. Of the 281 people who donated the antibody-positive units, 62 (22.1%) had documented seroconversion during these 5 months. An epidemiologic study of 54 seropositive and 58 seronegative donors was carried out. The HIV serologic status did not change in any of these donors after repeat testing. Only 13.0% of the seropositives and 15.5% of the seronegatives had any of the known risk factors for AIDS. There was a direct relationship between frequency of plasma donation and the risk of being seropositive. A survey of employees disclosed the frequent re-use of disposable blood collection equipment. We conclude that HIV transmission had probably occurred in this plasma collection center.
PIP: This report provides the results of a study of plasma donor clients from records abstracted between June-October 1986. The purpose was to identify risk factors for HIV infection among donors at the National Center for Blood Transfusions. Screening for HIV among donors began in May 1986. 54 Seropositive donors were identified and located from 281 and 58 seronegative donors were randomly selected. 16 employees of the plasma collection center were locatable and also included in the study. The results were that seroprevalence increased between June-October from 6.3% to 9.2%. The total donations were 3201 of which 294 were seropositive. Of 281 seropositive clients, 62 (22%) had seroconversion (a prior seronegative donation). Seroconversions increased from 1.6% in July to 50% in October. On retesting of the 112 study participants, no change in status was found. The groups were similar and both groups had relatively low risk factors for (13% for HIV seropositive and 15.5% for HIV seronegative donors). The rate of seropositivity increased with the frequency of plasma donations from 19.6% for those donating 1-3 times/month to 88.9% for those donating 10 times/month. Of the 16 employees, 1 died who was HIV seropositive; 5 were directly involved in plasma collection and reported reuse of saline solution and intravenous tubing. The results lead the authors to suggest that HIV was transmitted in the collection process. Support for this suggestion comes from the number of seroconversions; the risk factors among the seropositive donors had no known risk factors. Although not statistically significant, male seropositive donors had greater contract with prostitutes in Mexico City, but prostitutes had shown in the past 2 years a seropositivity rate of 1%. More demonstrative evidence comes from the increased rate of seropositivity with frequency of donation, and the employee reports of reutilization of blood collection materials. Other studies have postulated plasma donor site risk. Regardless of the expense of intravenous equipment, it is suggested that the risk of HIV transmission precludes reuse of materials. At present, all blood is collected from volunteer donors with disposable equipment. Other countries need to assess the safety of blood donor centers, particularly with paid donors.
Assuntos
Bancos de Sangue/normas , Doadores de Sangue , Contenção de Riscos Biológicos/normas , Soropositividade para HIV/epidemiologia , Adulto , Bancos de Sangue/economia , Sangria/instrumentação , Contaminação de Equipamentos , Feminino , Soroprevalência de HIV , Humanos , Infecção Laboratorial/etiologia , Masculino , México/epidemiologia , Plasmaferese/instrumentação , Fatores de Risco , Fatores Socioeconômicos , População UrbanaRESUMO
Tuberculosis infection surveys are carried out by tuberculin skin test (Mantoux) which is a simple, cheap, valid and reliable procedure for the estimation of prevalence and incidence rates. In 1987 a survey was undertaken in children of 6-7 years old who attended the elementary school and who were not vaccinated (BCG) in the region of Iguala, México. Out of 6,095 children of such age group, just 531 were not vaccinated, thus the prevalence figure was 2.5% (CL05 = 0.1%, 5.3%). On the basis of the findings by Izaguirre et al, 26 years ago, who reported that about 10% of the children of this age group were infected, it can be estimated that the annual risk of infection is about three newly infected each year per 1,000 population. It is necessary to provide better estimates of the whole tuberculosis incidence rate.
Assuntos
Teste Tuberculínico , Tuberculose Pulmonar/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , MéxicoRESUMO
Data on 2062 reports from the Monitoring System for Adverse Events Following Immunization, Centers for Disease Control (CDC), were analyzed to compare the risk of a personal or family history of convulsions in children who had a neurologic adverse event after receipt of diphtheria-tetanus-pertussis (DTP) vaccine with those who had a nonneurologic adverse event. Children with a neurologic event after DTP vaccine had a 7.2 times higher risk for personal history of convulsions (95% confidence limits 4.5 to 11.5) and a 4.5 times higher risk for family history of convulsions (95% confidence limits 3.1 to 6.7) than did children with an adverse event that did not affect the nervous system. Children with either a febrile or nonfebrile convulsion after receipt of DTP were significantly more likely to have a personal history of convulsions than children with a nonneurologic adverse event (P less than 0.0001). Children with a febrile convulsion after receipt of DTP but not children with nonfebrile convulsions were significantly more likely to have a family history of convulsions than those with a nonneurologic adverse event. It is recommended that pertussis vaccination be deferred in children with a personal history of a convulsion until it can be determined that an evolving neurologic disorder is not present. If such disorders are found, these children should be given the combined pediatric diphtheria and tetanus toxoids (DT) vaccine to complete the series.
Assuntos
Toxoide Diftérico/efeitos adversos , Doenças do Sistema Nervoso/etiologia , Vacina contra Coqueluche/efeitos adversos , Convulsões/etiologia , Toxoide Tetânico/efeitos adversos , Criança , Pré-Escolar , Vacina contra Difteria, Tétano e Coqueluche , Combinação de Medicamentos/efeitos adversos , Humanos , Lactente , Recém-NascidoRESUMO
Nutritional status surveillance data based on the clinical diagnosis of malnutrition and on weight-for-age, as well as diarrhoeal disease data for preschool age children attending government health clinics in El Salvador are presented for a 3-year period (1975 - 77). Surveillance results indicated consistently higher rates of clinical malnutrition and weight-for-age deficit in rural children as compared with urban children, and higher malnutrition rates in children 1 - 4 years of age as compared with infants less than 1 year old. Consistent seasonal increases in malnutrition were observed that were most pronounced in older preschool children (1 - 4 years) in rural areas. Seasonal peaks in malnutrition consistently followed 1 - 2 months after the major seasonal peak in diarrhoea at the onset of the rainy season, suggesting that diarrhoea may play a role in the etiology of malnutrition. A secondary seasonal peak in diarrhoea in the cooler, dry season was most prominent in infants but was not related to increased malnutrition. These results indicate that nutritional and health status indicators formed from data collected regularly at health centres can demonstrate consistent age group, urban/rural, and seasonal differences in nutritional status that may be useful in identifying risk groups and in monitoring nutritional changes for planning and evaluation purposes.
Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Inquéritos Nutricionais , Peso Corporal , Pré-Escolar , Diarreia/epidemiologia , El Salvador , Humanos , Lactente , Distúrbios Nutricionais/epidemiologia , População Rural , Estações do Ano , População UrbanaRESUMO
Data are presented to quantify the relationship between nutritional status and diarrheal disease reported in a 1-week period in children in El Salvador. A strong association was observed between reported diarrhea and combined wasting (defined by low weight-for-height) and stunting (defined by low height-for-age). This association held for all age groups studied and was consistently observed in the seasons of low and high prevalence of malnutrition. There were also significant associations between reported diarrhea and wasting alone, low weight-for-age, and low arm circumference. No consistent association was observed between reported diarrhea and stunting or chronic undernutrition as defined by low height-for-age, suggesting that short stature is not, by itself, a risk factor for diarrhea. Previously defined seasonal patterns of malnutrition for El Salvador as a whole were confirmed and appear to affect some geographic subregions more severely than others. Definition of these regional and seasonal patterns of malnutrition and their association with diarrhea has implications for the targeting and timing of nutrition interventions.
Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Diarreia/epidemiologia , Estatura , Peso Corporal , Criança , Pré-Escolar , Diarreia/etiologia , El Salvador , Humanos , LactenteRESUMO
PIP: An ongoing nutritional surveillance system has 2 advantages: 1) it provides information less expensively than would a nutritional survey; and 2) data can be available on a continuous routine basis within a few weeks or months after collection. Nutritional surveillance systems ideally should 1) be multisectorial in design; 2) be organized within the framework of existing information channels; 3) be based on a standard set of indicators selected after careful assessment of their validity; and 4) be aimed towards vulnerable population groups. This report describes the development of a nutritional status surveillance activity within the Ministry of Health of El Salvador for use in health planning and evaluation. However, the surveillance activity in El Salvador was not multisectorial in design but was developed solely within the health sector because it was felt that nutritional surveillance could best be developed in a step-by-step manner and that monitoring nutritional status within the health sector was a logical first step. Other causal factors in malnutrition can then be added later as resources and opportunities permit to form a more comprehensive surveillance system. Steps in the project development in El Salvador included: 1) recognition of need; 2) evaluation of indicators (e.g., clinical diagnosis indicator and weight-for-age indicator), and; 3) design of surveillance data collection system. It is hoped that in the future, data from other sectors can be combined with the nutritional status data to form what could justifiably be termed a 'nutritional surveillance system'.^ieng