Complete Genome Sequence of Human Coronavirus OC43 Isolated from Mexico.

We report the complete genome sequence of the first Mexican human coronavirus (HCoV) OC43, obtained by new-generation sequencing and a metagenomic approach, isolated from a child hospitalized with pneumonia. The genome is closely related to the other OC43 genome sequences available, ranging from 99.8% to 98.2% nucleotide sequence identity.

Acinetobacter baumannii infections in a tertiary care hospital in Mexico over the past 13 years.

BACKGROUND: Acinetobacter baumannii has evolved from an opportunistic pathogen into a common and persistent nosocomial bacterium capable of causing severe infections during endemic and epidemic periods. METHODS: The study period extended from January 1999 to December 2011 and involved patients hospitalized at the Hospital Civil de Guadalajara, Fray Antonio Alcalde, Jalisco, Mexico. From each patient, a single isolate was obtained, and a total of 3,680 unique isolates were collected. Susceptibility tests were performed according to the guidelines of the Clinical and Laboratory Standards Institute. RESULTS: A. baumannii has disseminated throughout the Hospital Civil de Guadalajara, Fray Antonio Alcalde, since 1999. A. baumannii isolates obtained from patients treated in the adult intensive care unit represent the majority of the isolates that have been collected. In addition, A. baumannii was isolated from the adult neurosurgical ward and the adult internal medicine ward, and these isolates were frequently obtained from secretions. A persistent decrease in the susceptibility of A. baumannii isolates to meropenem (92% in 1999 to 12% in 2011), imipenem and amikacin has been observed. CONCLUSIONS: A. baumannii became an endemic nosocomial pathogen during the study period at the Hospital Civil de Guadalajara, Fray Antonio Alcalde, and has exhibited a persistent decrease in susceptibility to all categories of antimicrobial agents over the past 13 years.

Mexican anthropometric percentiles for ages 10-18.

OBJECTIVE: To elaborate Mexican growth charts based on international methodology. DESIGN: Data were obtained from the Mexican National Health Survey. The survey was stratified and probabilistic representative of all the country. SETTING: Nationwide open population living in urban and rural areas. SUBJECTS: Boys (8545) and girls (9983) from 10 to 18 years participating in the survey. METHODS: Age, weight and height were recorded. Empirical percentiles were calculated and smoothed. Smoothed curves were approximated using least-mean square estimation. RESULTS: Tables and figures for percentile values of weight, height and body mass index (BMI) for age, as well as percentile values of weight and BMI for height for both genders are presented. Regarding 50th BMI for age percentiles, Mexicans had higher levels than the Americans in the Centers for Disease Control and Prevention growth charts; Mexicans were lower but had similar weights than the Americans. Owing to the high BMI, the percentile corresponding to an overweight level (25 kg/m(2)) at 18 years was 74.5 in boys and 72.5 in girls, whereas obesity level (30 kg/m(2)) at 18 years was 97.3 and 97.4 in boys and girls, respectively. CONCLUSIONS: The present growth charts are snapshots of a Mexican population. Because of the high median BMI compared to US and World Health Organization standards, we must be cautious in establishing an upper normal cutoff for clinical normality, not merely selecting the 85th and 95th percentiles as equivalents of overweight and obesity, respectively. Therefore, we proposed percentiles 74.5 in boys and 72.5 in girls as the action points of overweight as they are the percentiles corresponding to BMI 25 kg/m(2) at 18 years. SPONSORSHIP: The survey was supported by the Mexican Minister of Health. Statistical analyses were sponsored by Dr Del-Rio-Navarro.

Molecular epidemiology of Entamoeba spp.: evidence of a bottleneck (Demographic sweep) and transcontinental spread of diploid parasites.

Entamoeba histolytica causes amebic colitis and liver abscess in developing countries such as Mexico and India. Entamoeba dispar is morphologically identical but is not associated with disease. Here we determined the ploidy of E. histolytica and developed PCR-based methods for distinguishing field isolates of E. histolytica or E. dispar. Fluorescence in situ hybridization showed that E. histolytica trophozoites are diploid for five "single-copy" probes tested. Intergenic sequences between superoxide dismutase and actin 3 genes of clinical isolates of E. histolytica from the New and Old Worlds were identical, as were those of E. dispar. These results suggest a bottleneck or demographic sweep in entamoebae which infect humans. In contrast, E. histolytica and E. dispar genes encoding repeat antigens on the surface of trophozoites (Ser-rich protein) or encysting parasites (chitinase) were highly polymorphic. chitinase alleles suggested that the early axenized strains of E. histolytica, HM-1 from Mexico City, Mexico, and NIH-200 from Calcutta, India, are still present and that similar E. dispar parasites can be identified in both the New and Old Worlds. Ser-rich protein alleles, which suggested the presence of the HM-1 strain in Mexico City, included some E. histolytica genes that predicted Ser-rich proteins with very few repeats. These results, which suggest diversifying selection at chitinase and Ser-rich protein loci, demonstrate the usefulness of these alleles for distinguishing clinical isolates of E. histolytica and E. dispar.

[FARMAC: a program designed for monitoring the prescription of antimicrobials in hospitals]. / FARMAC: programa diseñado para vigilar la prescripción de antimicrobianos en hospitales.

INTRODUCTION: The use of computer programs for monitoring the prescription of antimicrobial agents in hospitals is of paramount importance in the incorporation of electronic databases developed and analyzed by several hospital committees, including the following: infection control; pharmacy; morbidity and mortality; and quality assurance committees, as well as other key areas or departments such as pathology, pharmacy, microbiology, radiology, or hospital administration. OBJECTIVE: To describe the development and use of an "information system" employed for monitoring the prescription of antimicrobial agents in hospitalized patients. MATERIAL AND METHODS: A printed format was developed in order for physicians to ask for authorization for the use of restricted antimicrobial agents (i.e. third-generation cephalosporins and other newly introduced beta lactams, fluoroquinolones, antifungals, antivirals, etc). A computer program, "FARMAC", was designed using the Dbase IV program. FARMAC contemplates the presentation on a screen of a main menu allowing for the use of several options: admissions; antibiotic changes; consultations; discharges; hospital transfers; reports, and distribution. The reports are generated from the menu and appear on the screen or are printed in representative tables and figures. Generally speaking, the system processes information on the use of antimicrobial agents, files information, allows for consultation, of the information and generates reports quickly and efficiently. RESULTS: The presentations were defined on screen, taking into account the space needed in order to avoid an inadequate distribution of the messages, therefore obtaining an optimal image. A database was created defining the necessary fields for storing information with reference to patients and usage patterns of restricted antimicrobial agents. DISCUSSION: The development of an information and surveillance system on the prescription of antibiotics allows for consulting updated information, making the data analysis easier for decision making. Its use will allow for surveying tendencies and usage patterns of controlled and non-controlled antimicrobial agents.

Survey of drug resistance of Mycobacterium tuberculosis in 3 Mexican states, 1997.

BACKGROUND: Drug resistance threatens global tuberculosis (TB) control efforts. Population-based estimates of drug resistance are needed to develop strategies for controlling drug-resistant TB in Mexico. OBJECTIVE: To obtain population-based data on Mycobacterium tuberculosis drug resistance in Mexico. METHODS: To obtain drug resistance data, we conducted a population-based study of TB cases in the states of Baja California, Sinaloa, and Oaxaca, Mexico. We performed cultures and drug susceptibility testing on M tuberculosis isolates from patients with newly diagnosed, smear-positive TB from April 1 to October 31, 1997. RESULTS: Mycobacterium tuberculosis was isolated from 460 (75%) of the 614 patients. Levels of resistance in new and retreatment TB cases to 1 or more of the 3 current first-line drugs used in Mexico (isoniazid, rifampin, and pyrazinamide) were 12.9% and 50.5%, respectively; the corresponding levels of multi-drug-resistant TB were 2.4% and 22.4%. Retreatment cases were significantly more likely than new cases to have isolates resistant to 1 or more of the 3 first-line drugs (relative risk [RR], 3.9; 95% confidence interval [CI], 2.8-5.5), to have isoniazid resistance (RR, 3.6; 95% CI, 2.5-5.2), and to have multi-drug-resistant TB (RR, 9.4; 95% CI, 4.3-20.2). CONCLUSIONS: This population-based study of M tuberculosis demonstrates moderately high levels of drug resistance. Important issues to consider in the national strategy to prevent M tuberculosis resistance in Mexico include consideration of the most appropriate initial therapy in patients with TB, the treatment of patients with multiple drug resistance, and surveillance or periodic surveys of resistance among new TB patients to monitor drug resistance trends.

Improved serological response to human diploid cell rabies vaccine when given simultaneously with antirabies hyperimmune globulin.

BACKGROUND: The prevention of rabies in Mexico continues to be an important goal for the health sector. Although the prevalence of this disease continues to fall, between 1990 and 1995 a total of 238 cases were registered (an average of 40 cases annually), with a mean annual incidence of 0.04 cases per 100,000 inhabitants and a mortality of almost 100%, so that it is important to rely on highly effective vaccines with few side effects. The objective of this work was to evaluate seroconversion and tolerance to the human diploid cell antirabies vaccine administered to individuals with a history of exposure to rabies, to compare these results with those reported in the literature for the Fuenzalida vaccine, a rabies vaccine produced in the brain tissue of suckling mice, and to find the role antirabies hyperimmune gamma globulin plays in the concentration of post-vaccination antibody concentrations. METHODS: An analytical transverse study was carried out in 40 children and adults with a history of rabies exposure who were given a complete, five-dose intramuscular schedule of the human diploid cell rabies vaccine. Subjects were followed daily, and local and systemic signs and symptoms were recorded. Two blood samples (at baseline and at the end of the vaccination schedule) were taken and antibody titers against rabies glycoprotein, using the ELISA technique, were measured. RESULTS: Adverse side effects produced by the human diploid cell antirabies vaccine, such as frequency of pain, erythema, itching, and regional adenopathy were fewer than those reported in the literature for the Fuenzalida vaccine (p < 0.05), and of induration and local pain (p < 0.05) in relation to the latter vaccine. All patients seroconverted, producing geometric mean antibody titers of 6.22 IU/mL, an arithmetic mean titer of 9.66 IU/mL with a SD of 9.1 IU/mL. The level of tolerance to the diploid cell vaccine was good and its adverse effects were minimal and fewer than those reported for the Fuenzalida rabies vaccine. Patients receiving the diploid cell vaccine plus antirabies hyperimmune gamma globulin developed higher antibody titers (measured by ELISA test) at the end of the vaccination schedule than those only receiving the vaccine. CONCLUSIONS: These results are important in order to achieve an adequate and opportune level of protection provided by prophylactic vaccines to patients with exposure to rabies.

[Surveillance and the costs related to the prescription of antimicrobials in a pediatric hospital]. / Vigilancia y costos relacionados con la prescripción de antimicrobianos en un hospital pediátrico.

INTRODUCTION: Important considerations in the selection of an antimicrobial agent include the indications for its prescription, its efficacy, toxicity and cost. However, is has been observed that up to 50% of these prescriptions are inappropriate. OBJECTIVE: To evaluate the utilization patterns and costs of restricted antimicrobial agents requiring authorization of the infectious diseases service for their prescription, in a tertiary care pediatric hospital through the use of a computer software antimicrobial use surveillance program designed by the investigators. MATERIAL AND METHODS: A one-year longitudinal descriptive and prolective survey was conducted in all patients requiring antimicrobial therapy during their hospitalization. Information on the prescription and costs of antimicrobial agents was recorded from both the medical chart and pharmacy registers. RESULTS: A total of 748 patients were prescribed at least one restricted antimicrobial agent, corresponding to 9.6% of the total number of patients hospitalized and 63.4% of the antibiotic expenditures during the study. CONCLUSIONS: Hospital surveillance of antimicrobial prescription is useful for detecting antimicrobial prescription patterns and costs. These types of studies are inexpensive and of easy access when a computerized register is available in the pharmacy.

Onchocerciasis: changes in transmission in Mexico.

There are now three endemic foci of onchocerciasis in Mexico, all located in mountainous areas in the south-east: two in the state of Chiapas and one in the state of Oaxaca. Together, these three foci cover 16,900 km2 and contain about 286,000 people in 947 localities, most of the localities being small and scattered. The main economic activity in all the foci is coffee farming. Introduction of Mectizan (ivermectin, MSD) into Mexico in 1989 revolutionized control of onchocerciasis in the country and made elimination of the disease a reasonable goal. Concerted efforts between 1989 and 1997, supported by Merck & Co., the River Blindness Foundation and the Onchocerciasis Elimination Programme in the Americas, have led to steady decreases in the incidence of new cases, nodule prevalence and skin-snip positivities. The improvement has been most marked in the Oaxaca focus, where transmission may have been interrupted. As prior to attempts at control, the largest populations at risk are in the Chiapas foci, where logistical problems and migration have combined to limit the success of local control programmes.

[Effect of levamisole on microbicidal activity and chemotaxis in polymorphonuclear cells]. / Efecto del levamisol en la actividad microbicida y quimiotaxis en células polimorfonucleares.

AIMS: Neonatal septicemia may have a mortality of 20% in newborns small for their-gestational age. This susceptibility for infections has been explained by immunological disorders. The aim of this study to know the effect of levamisole on the functions of chemotaxis and bacterial activity of PMN cells in newborns small for their-gestational age. MATERIAL AND METHODS: Twenty full-term newborns were studied. Ten of them were small for their-gestational age, and the other 10 had body weight within the normal range. Microbicidal activity and chemotaxis were measured, and comparisons between groups were made with non-parametric statistical tests. RESULTS: In the group of newborns small for their-gestational age. Microbicidal activity was similar to control group, but chemotactic activity was reduced (p < 0.05).

[Advances in the molecular diagnosis of infectious and parasitic diseases]. / Avances en el diagnóstico molecular de las enfermedades infecciosas y parasitarias.

During the last decade molecular diagnostic techniques have moved from the research laboratory into the clinical microbiology laboratory. The application of molecular biology for the diagnosis of infections and parasitic diseases by the detection of nucleic acids has steadily grown, and it is very probably that, while they may not displace the traditional diagnostic laboratory, they will be common place in the not to distant future. A detailed description of the principal molecular diagnostic techniques that are currently being used or that have a potential use for the diagnosis, evaluation of disease progression or response to therapy of selected infectious and parasitic diseases, is presented. Emphasis is placed on the rational use of these techniques in regional reference laboratories or highly specialized hospitals; the importance of selecting and implanting those diagnostic techniques with the highest cost-benefit ratio; and finally, the need to train human resources which are highly qualified in the theory and practice of molecular biology.

In vitro effect of complete Staphylococcus aureus extract on chemotaxis of polymorphonuclear cells in children with bronchial asthma and chronic relapsing upper airways infections.

UNLABELLED: Chemokinesis and chemotaxis were measured in polymorphonuclear cells (PMN) from 51 children aged 1 to 8 years old, of either sex. Case group--41 non-allergic asthmatic children with chronic relapsing upper airways infections, diagnostic criteria were history of wheezing associated to an upper airways infection episode and negative skin tests. CONTROL GROUP: 10 healthy children. A sample of 10 ml of peripheral venous blood was drawn. PMN were incubated with Hank's solution to measure chemokinesis and with C5a and Staphylococcus aureus extract to measure chemotaxis. Chemokinesis values in healthy control children and in patients with non-allergic bronchial asthma were of 46.0 +/- 7.1 vs 23.8 +/- 6.1 microns (p < 0.01). C5a-stimulated chemotaxis values in healthy control children and in patients with non-allergic bronchial asthma were of 91.0 +/- 21.3 vs 92.3 +/- 21.0 microns (ns), and Staphylococcus aureus extract-stimulated chemotaxis values in healthy control children and in patients with non-allergic bronchial asthma were of 97.0 +/- 22.4 vs 92.0 +/- 23.0 microns (ns). These results suggest that PMN from children with non-atopic asthma have reduced chemokinesis. After a chemotactic stimulus with C5a and bacterial extract, leukocyte motility is corrected and reach similar values to that present in healthy children.

Burden of Mycobacterium tuberculosis in sputum samples can be reliably determined using a quantitative, non-radioactive polymerase chain reaction assay.

OBJECTIVE: To develop a rapid assay for quantitation of Mycobacterium tuberculosis in sputum samples using the competitive polymerase chain reaction (PCR) and a colorimetric microtiter well detection format. DESIGN: The assay relies on the co-amplification of a 419 base pair (bp) pab fragment of M. tuberculosis together with a target template (pab/tet) made by splicing a fragment of tet excised from pbr322 between the 5' and 3' ends of the pab fragment to create a 380 bp hybrid template amplified with the same primers but readily distinguishable using probes specific for either pab or tet. RESULTS: We demonstrate a good correlation between the results obtained using this assay and the results of quantitative culture. CONCLUSION: This assay provides quantitative information regarding M. tuberculosis burden in samples containing between 10(3) and 10(8) colony forming units/milliliter (CFU/ml).

[Prevalence of Haemophilus influenzae carrier state in children in Ciudad Nezahualcóyotl, State of Mexico, Mexico]. / Prevalencia de estado de portador de Haemophilus influenzae en niños de Ciudad Nezahualcóyotl, estado de México, México.

OBJECTIVE: To determine the prevalence of H. influenzae (Hi) carrier state among children, in Ciudad Nezahualcóyotl, State of Mexico. MATERIAL AND METHODS: A cross-sectional comparative random study was designed. Study subjects were 639 children under 15 years of age, stratified by age and sex. Nasopharyngeal cultures were used to identify Hi and to typify encapsulated strains. Sample size was computed with the software package Epi-Info, using a p value of 0.5%, 95% confidence intervals and a 5% error; statistical analysis was performed using frequencies, means and proportions. Differences were tested by comparison of two proportions from independent populations. RESULTS: Hi was isolated from 136 of 639 pharyngeal cultures (21%). Hi types found were Hi b (n = 6, 4%), Hi a, c, and f (n = 5, 4%), and non-typifiable (NT) Hi (n = 125, 92%). CONCLUSIONS: The prevalence of pharyngeal colonization by Hi found among children under 15 years of age, in Ciudad Nezahualcóyotl, is similar to that reported in the literature. The inverse relation of pharyngeal carriers with age can be accounted for by the progressive development of specific and non-specific immunity against encapsulated and non-encapsulated strains.

[HIV infection in Mexican children]. / Infección por VIH en niños mexicanos.

OBJECTIVE: To review the experience of the Immunodeficiency Clinic of the Department of Infectious Diseases at Hospital Infantile de México "Federico Gómez", in the management of children with HIV infection and AIDS. MATERIAL AND METHODS: the medical records of 130 patients with a clinical and laboratory diagnosis of HIV/AIDS seen between September 1985 and June 1994 were reviewed. Data was obtained regarding diagnosis, epidemiological risk factors, clinical features, types and numbers of bacterial and opportunistic infections, malignancies, hospitalizations, general and specific treatment and outcome. The diagnosis followed CDC guidelines and was established in all 130 patients serologically with ELISA and Western Blot. In infants < 18 months, diagnosis was made by detection of p24 and/or viral culture in two separate occasions. RESULTS: Data from 130 subjects was obtained; 74 were male and 56 female for a M:F ratio of 1.3:1. With regards to mode of transmission, 62.3% was vertical, 20.8% post transfusion, 8.5% hemophiliacs (the latter two males were cases before occurred 1987), 6.2% sexual and 2.2% unknown. With regards to additional risk factors, in 35 cases the parents were heterosexual, in 18 one parent had a history of transfusion, and in eight the father was bisexual. According to the CDC classification; 16 had indeterminate infection or PO; nine were asymptomatic or P1; and 105 were symptomatic or P2. Eighty two patients had nonspecific findings, 60 had neurologic manifestations, 18 had lymphocytic interstitial pneumonia and four had secondary malignancies. It was possible to document 296 episodes of secondary infections: 154 bacterial, 58 opportunistic, and 84 with other pathogens. CONCLUSIONS: in Mexico, as in other Western countries, vertical transmission has become the dominant form of acquiring HIV infection in children, reflecting a change in the epidemiology of infection in women of child bearing age. Moreover, since IV drug use is a very limited phenomenon in Mexico, heterosexual transmission is the major form of transmission in women.