Health interventions for the metal working industry: which is the most cost-effective? A study from a developing country.

This study ranked the cost-effectiveness of health interventions in the metal working industry in a developing country. Data were based on 82 034 workers of the Northern region of Mexico. Effectiveness was measured through 'healthy life years' (HeaLYs) gained. Costs were estimated per worker according to type and appropriate inputs from selected health interventions. 'Hand' was the anatomical region that yielded the most gain of HeaLYs and amputation was the injury that yielded the most gain of HeaLYs. The most effective health intervention corresponded to training, followed by medical care, education, helmets, safety shoes, lumbar supports, safety goggles, gloves and safety aprons. In dollar terms, education presented the best cost-effectiveness ratio (US$637) and safety aprons presented the worst cost-effectiveness ratio (US$1 147 770). Training proved to be a very expensive intervention, but presented the best effectiveness outcome and the second best cost-effectiveness ratio (US$2084). Cost-effectiveness analyses in developing countries are critical. Corporations might not have the same funds and technology as those in developed countries or multinational companies.

[Detection of Norwalk and Mexico viruses, two human Caliciviruses in stools of Chilean children]. / Detección de virus Norwalk y México, dos calicivirus humanos en deposiciones de niños chilenos.

BACKGROUND: Human calciviruses (HuCVs) cause diarrhea outbreaks associated with consumption of contaminated food and water. Seroepidemiological studies in developing countries, suggest that HuCVs can cause acute gastroenteritis in children. AIM: To study the presence of Norwalk (NV) and Mexico (MX) virus, two HuCVs, in stools of Chilean children from different settings. SUBJECTS AND METHODS: ELISA tests for NV and MX were performed in 677 stool samples for children aged 0 to 132 years old, with acute diarrhea occurring in day care centers or consulting in outpatient clinics or emergency rooms. We also studied eight samples from children involved in a diarrhea outbreak that occurred in a rural community in 1992. A subset of samples was tested with polymerase chain reactions using different primers. RESULTS: Only one sample from a child with acute diarrhea occurring in a day care center was positive for HuCV by polymerase chain reaction. Three samples from the outbreak were positive by the latter method and by ELISA. The HuCV obtained from the day care center was genetically different from other known HuCV. CONCLUSIONS: Despite the high seroprevalence, NV and MX viruses were detected in a very low proportion of Chilean children stools.

Quality differences between rural and urban primary care: the case of a cervical cancer screening programme.

OBJECTIVE: To measure the difference between rural and urban primary care quality in terms of an early cervical cancer detection programme. LOCATIONS: Seven hundred and fifty smear reports from rural primary care units and 750 from urban primary care units were selected at random from three institutions: the Ministry of Health, the largest Mexican social security institution, and one University Hospital, during August 1995-March 1996. Excluded were reports from women who were pregnant, menopausal or those who had undergone hysterectomy, as well as those tested positive for dysplasia and cancer. ACTIVITIES: Quality was measured through indicators and standards set by consensus of recognized field experts, based mainly on recommended national and international parameters. RESULTS: There was no difference between the overall quality of the urban and rural units. Both registered fairly satisfactory levels (achievement: 76.2%; 95% CI: 72.7-77.0%, versus 75.2; 95% CI: 69.8-78.9%, respectively). The quality of the smear sampling was highly unsatisfactory in rural units and unsatisfactory in urban units (achievement: 64.2%; 95% CI: 58.2-70.0%, versus 47.3%, 95% CI: 42-52.7%; P < 0.00001). Quality of coverage was unsatisfactory for both regions. Quality of smear processing and timeliness were highly satisfactory for both rural and urban units. RECOMMENDATIONS: Efforts should be directed toward smear quality improvement, especially in rural units. Health care workers who take smears need training programmes and better instruments. They should receive feedback on smear adequacy from the laboratory. Health education is necessary to improve utilization and programme coverage quality.

Effect of quality of care on preventable perinatal mortality.

This study assessed and quantified the effect of quality of care on death preventability, independent of social and biological variables. One hundred and eighty-one avoidable perinatal deaths (cases) were compared to 341 non-avoidable ones (controls). Judgement criteria on death preventability were based predominantly on compliance with explicit hospital medical care standards, determined by peer review. The overall perinatal mortality rate was 24.8 per 1000 births and could be reduced by 35% if all avoidable perinatal deaths were prevented. Sixteen per cent of the deaths presented structural and 31.2% process deficiencies; both predominated among avoidable perinatal deaths (35.4% vs 5.3%, p < 0.000; and 79.3% vs 5.9%, p < 0.000, respectively). Structural deficiencies increased the risk of an avoidable perinatal death eleven-fold (95% confidence interval (CI) 4.1, 26.9; p < 0.001) and process deficiencies eighty-eightfold (95% CI 37.2, 204.5, p < 0.001), after controlling for confounders. The strength of the association between quality of care and preventable perinatal mortality was estimated.

[Molecular study of 6 episodes of nosocomial infections produced by methicillin resistant Staphylococcus aureus]. / Estudio molecular de 6 episodios de infección intrahospitalaria causados por Staphylococcus aureus meticilino-resistente.

A critical step in any epidemiologic research concerning nosocomial infections is the precise identification of the responsible pathogen. The present work utilized a molecular approach -plasmids identification, restriction length polymorphism DNA analysis, and random amplified polymorphic DNA- for the characterization of 6 nosocomial outbreaks due to 52 strains of methicillin-resistant Staphylococcus aureus (MRSA). In these episodes, the clinic-epidemiologic and phenotypic analysis (antibiotype) pointed to a nosocomial infection. Through molecular analysis it was possible to establish, in a very precise way, clonality due to MRSA strains in 2 of the studied outbreaks; the same type of analysis allowed to eliminate a MRSA clonal origin in the remainder 4 episodes. The antibiogram was not an useful analytic tool due to its poor discriminatory power. Also, through a PCR procedure, it was possible to identify the presence of the gen mecA in every of the 52 MRSA strains studied.

Enzymatic DNA amplification (PCR) in the diagnosis of extrapulmonary Mycobacterium tuberculosis infection.

A polymerase chain reaction able to amplify Mycobacterium tuberculosis DNA from clinical samples of extra-pulmonary origin is described. The PCR amplified a 294 base pair DNA fragment spanning positions 5'-782 to 3'-1075 of the 65 kDa M. tuberculosis antigen gene. The procedure enables amplification of target DNA at quantities as low as 1 pg of purified material and less than 1000 mycobacteria present in clinical samples. The reaction amplifies M. tuberculosis DNA as well as Mycobacterium bovis BCG DNA. In 34 extra-pulmonary clinical samples studied, 18 rendered positive results and two false-negative results; compared to classical diagnostic procedures, the sensitivity was 90% and specificity 100%. The PCR approach to diagnosis of tuberculosis of extra-pulmonary origin is a valid diagnostic alternative to classical procedures.

[Amplification of 2 different gene segments of Mycobacterium tuberculosis and its usefulness in the diagnosis of tuberculosis]. / Amplificación de 2 segmentos génicos diferentes de Mycobacterium tuberculosis y su utilidad en el diagnóstico de la tuberculosis.

The infection caused by Mycobacterium tuberculosis is highly prevalent in our country and is considered an emergent pathology in developed countries. The amplification of specific gene segments with diagnostics purposes is an alternative to identify fastidious and slow growing infective agents, being Mycobacterium tuberculosis one of them. Two polymerase chain reactions (PCR) directed to the amplification of a 294bp gene segment encoding a portion of a 65KD heat shock protein and 317 bp gene segment of a repetitive DNA segment (IS 6110) of Mycobacterium tuberculosis, have a sensibility of 80 to 91.3% and a specificity of 83.9 to 100% when used in the identification of Mycobacterium tuberculosis in 2 group of clinical samples, both compared to Koch's culture and or Ziehl-Neelsen stain. The diagnostic procedure is particularly useful in diagnosis of tuberculosis of extrapulmonary origin.

Infección por virus de inmunodeficiencia humana: uso de métodos Western Blot como pruebas de confirmación / Infection by HIV-I: Western Blot as confirmation test

Evaluamos la respuesta serológica de 224 muestras de suero para infección por VIH-1 mediante dos sistemas western blot; uno basado en un lisado viral (Epitope) y el otro en base a péptidos sintéticos y proteínas recombinantes (Lia-Tek). La sensibilidad y especificidad de ambos métodos fue de un 100%. Hubo un 10,3%de resultados indeterminados con el método Epitope. Este nivel de indeterminados se redujo a un 1,8%al ser analizadas las muestras con el método Lia-Tek. Sugerimos el uso de ambos métodos en forma secuencial para la confirmación de la respuesta de anticuerpos anti-VIH-1, y para la resolución del problema de los resultados indeterminados