Seroepidemiología del paludismo en un grupo de migrantes en tránsito (Chiapas, 2008)

OBJETIVO: Conocer la prevalencia del paludismo y los factores asociados con la infección de migrantes en la frontera sur de México, durante 2008. MATERIAL Y MÉTODOS: En 706 migrantes, se investigó la infección activa mediante prueba rápida y PCR o pasada, mediante serología y se aplicó un cuestionario para investigar las condiciones asociadas con la infección. RESULTADOS: 85.6% provenía de Centroamérica. Ninguno presentó infección activa; 4.2% fue seropositivo y la mayoría provenía de los países con mayor incidencia de paludismo en la región. La seropositividad se asoció con el número de episodios previos de paludismo (RM=1.44; IC95% 1.04-2.00), años de permanencia en su comunidad de origen (RM=1.03; IC95% 1.00 -1.07) y conocimiento y automedicación con antipalúdicos (RM=3.38; IC95% 1.48-7.67). CONCLUSIONES: La exposición previa de migrantes al paludismo y las dificultades para su detección indican la necesidad de nuevas estrategias para la vigilancia epidemiológica para estas poblaciones.

OBJECTIVE: To know the prevalence of malaria and the factors associated with the infection in migrants in the southern border of Mexico, during 2008. MATERIALS AND METHODS: In 706 migrants, active malaria infection was investigated using a rapid diagnostic test and PCR and past infection using serology. A questionnaire was applied to investigate the conditions associated to infection. RESULTS: 85.6% originated from Central America, none presented an active infection, although 4.2% were seropositive, most of these came from the countries with the highest malaria incidence in the region. Seropositivity was associated with the number of previous malaria episodes (OR=1.44; IC95% 1.04-2.00), years living in their community of origin (OR=1.03; IC95% 1.00-1.07), and knowledge and self-medication with anti-malaria drugs (OR=3.38; IC95% 1.48-7.67). CONCLUSIONS:. The previous exposure of migrants and the difficulties for their detection indicate the need of new strategies for the epidemiological surveillance for these populations.

Ethnic differences in survival for female cancers of the breast, cervix and colorectum in British Columbia, Canada.

BACKGROUND: Chinese and South Asians are among the fastest growing minority populations in Canada; however little is known about the burden of cancer in these populations. OBJECTIVE: The objective is to examine survival rates for breast, cervical and colorectal cancers in women within these two ethnic populations, as compared to the BC general population. METHODS: Survival rates were calculated for three time periods in the Chinese, South Asian and BC general populations, using the BC cancer registry. Ethnicity within the registry was determined using surnames. RESULTS: Survival rates for female breast, cervical and colorectal cancers have improved over time in all three population groups, however general differences were found among the groups. Chinese women had higher survival rates than both South Asians and all BC women for breast and cervical cancer, and intermediate survival rates between South Asians and all BC women for colorectal cancer. South Asian women had the highest survival rates for colorectal cancer, similar survival rates to all BC women for breast cancer, and lower survival rates for cervical cancer. INTERPRETATION: Differences in the observed survival rates may be explained by variations in screening and early detection, treatment practices, and cancer biology. This is discussed more fully for each cancer site.

Prevalence of HBV-genotypes in immigrants affected by HBV-related chronic active hepatitis

BACKGROUND: The genetic heterogeneity of the HBV genome has been established and eight genotypes can be classified according to the criterion of >8 percent differences in the complete nucleotide sequence of the viral genome. AIMS: To evaluate the prevalence of HBV-infection in a population of immigrants and to determine in patients with detectable serum HBV-DNA the HBV-genotypes. METHODS: Between January 2005 and December 2005 a total of 556 immigrants were tested for HBsAg. In HBsAg positive patients the biochemical and virological activity of infection and the possible presence of co-infections (HCV, HDV, HIV) were evaluated. In patients with detectable serum HBV DNA, the HBV-genotype was determined by INNOLiPA. RESULTS: Among the 556 subjects tested, 60 (10.7 percent) resulted HBsAg positive. All were men, and 42 (70 percent) come from Africa, 10 (16.6 percent) from Asia and 9 (14.4 percent) from East-Europe. 28/60 (46.6 percent) patients presented normal ALT levels (<40 IU/L) and undetectable serum HBV DNA (<100 copies/mL in real-time PCR), while 32 (53.4 percent) patients had ALT levels above laboratory normal values and detectable serum HBV DNA. Genotype distribution was as follow: genotype E, 16 (50 percent), genotype D, 9 (28.1 percent), genotype A, 7 (21.9 percent). CONCLUSION: Our study evidences a moderate prevalence of HBV-infection in immigrants, particularly in sub-Saharan African people, and the potentiality of migratory flow in the introduction of genotype non-D hepatitis B virus, potentially characterized by a different natural history and, possibly, a different response to antiviral treatment.

RACIONAL: A heterogeneidade do genoma do vírus da hepatite B (VHB) foi estabelecida e oito genótipos podem ser classificados de acordo com o critério de diferenças de percentagem maior ou igual a 8 na seqüência completa do nucleotídeo do genoma vira!. OBJETIVOS: Verificar a prevalência da infecção pelo vírus da hepatite B (VHB) em uma população de imigrantes na Itália e determinar os genótipos do VHB em pacientes com níveis séricos detectáveis do VHB-DNA. MÉTODOS: Entre janeiro e dezembro de 2005, o total de 556 imigrantes foram testados para o HbsAg. Se positivos, a atividade bioquímica e viral da infecção e a possível presença de co-infecções (HVC, HVD e HIV) foram examinadas. Nos pacientes positivos para o VHB-DNA, o genótipo do VHB foi determinado pelo método INNOLiPA. RESULTADOS: Entre os 556 pacientes, 60 (10,7 por cento) tinham HbsAg positivo. Todos eram do sexo masculino e 42 (70 por cento), provenientes da Africa, 10 (16,6 por cento) da Asia e 9 (14,4 por cento) do Leste Europeu. 28/60 (46,6 por cento) apresentaram níveis de ALT normais (<40 UI/L) e soro negativo ou indetectável para o VHB-DNA (<100 copies/mL PCR "real-time"), enquanto 32 (53,4 por cento) tinham níveis mais elevados de ALT e soro positivo para VHB-DNA. A distribuição do genótipo foi a seguinte: genótipo E, 16 (50 por cento), genótipo D, 9 (28,1 por cento), genótipo A, 7 (21,1 por cento). CONCLUSÃO: O estudo evidencia a prevalência moderada do HVB em imigrantes, particularmente na população africana, sub-Sahara e o potencial fluxo migratório na introdução da hepatite B, genótipo não-D, potencialmente caracterizada pela história natural e possivelmente levar à diferença no tratamento anti-viral.

Differences in risk factors, atherosclerosis and cardiovascular disease between ethnic groups in Canada: the study of health assessment and risk in ethnic groups (SHARE).

Cardiovascular disease rates vary greatly between ethnic groups in Canada. To establish whether this variation can be explained by differences in disease risk factors and subclinical atherosclerosis, we undertook a population-based study of three ethnic groups in Canada: South Asians, Chinese and Europeans. A total of 985 participants were recruited from three cities (Hamilton, Toronto and Edmonton) by stratified random sampling. Clinical cardiovascular disease was defined by history or electrocardiographic findings. Carotid atherosclerosis was measured with B-mode ultrasonography. Conventional (smoking, hypertension, diabetes, raised cholesterol) and novel risk factors (markers of a prothrombotic state) were measured. Within each ethnic group and overall, the degree of carotid atherosclerosis was associated with a higher prevalence of cardiovascular disease. South Asians had the highest prevalence of this condition compared with Europeans and Chinese (11%, 5% and 2%, respectively; p=0.0004). Despite this finding, Europeans had more atherosclerosis (mean of the maximum intimal medial thickness 0.75 [0.16] mm) than South Asians (0.72 [0.15] mm) and Chinese (0.69 [0.16] mm). South Asians had an increased prevalence of glucose intolerance, higher total and low-density lipoprotein cholesterol, higher triglycerides and lower high-density lipoprotein cholesterol, and much greater abnormalities in novel risk factors including higher concentrations of fibrinogen, homocysteine, lipoprotein(a), and plasminogen activator inhibitor-1. Although there are differences in conventional and novel risk factors between ethnic groups, this variation and the degree of atherosclerosis only partly explains the higher rates of cardiovascular disease among South Asians compared with Europeans and Chinese. The increased risk of cardiovascular events could be due to factors affecting plaque rupture, the interaction between prothrombotic factors and atherosclerosis, or as yet undiscovered risk factors.

Comparison of methods to assess coronary heart disease prevalence in South Asians.

BACKGROUND: Migrants from the Indian subcontinent (South Asian migrants) in the United Kingdom have high mortality from coronary heart disease (CHD) in comparison to the indigenous population. Few studies have assessed the prevalence of CHD in South Asians, and the applicability of conventional survey methods in this population is not known. In this pilot random population survey of South Asian men and women living in West London, the prevalence of CHD as judged by the Rose questionnaire, past cardiac history, cardiologist and resting electrocardiogram were compared. METHODS: Subjects aged 30-64 years from randomly selected households were invited for a cardiological assessment. A lay person administered the Rose questionnaire and recorded the past cardiac history. A cardiologist also made an independent assessment and a 12-lead electrocardiogram was recorded and analysed according to the Minnesota code. RESULTS: Three hundred and seventy-six individuals (192 men and 184 women) were assessed. The prevalence of angina in men and women, respectively, was 3.1% and 4.9% by the Rose questionnaire; 2.6% and 2.2% by past cardiac history; and 4.2% and 0.5% according to the cardiologist. The prevalence of myocardial infarction in men and women, respectively, was 5.2% and 2.2% by the Rose questionnaire, 3.6% and zero by past cardiac history and 3.6% and 0.5% by the cardiologist. Q/QS codes were present in 1.6% men and 0.5% women and ischaemic codes in 13% men and 14% women. Ischaemic changes were not associated with any cardiac history in 72% of men and 92% of women. For a diagnosis of CHD in men, there was poor agreement between the Rose questionnaire and either the past cardiac history or the cardiologist's assessment, but moderate agreement between the past cardiac history and the cardiologist. Agreement was poor between all three methods for a positive diagnosis of CHD in women. CONCLUSION: Current accepted epidemiological methods for assessing CHD prevalence may be inaccurate in South Asians, especially women. Electrocardiogram abnormalities suggestive of ischaemia are common in South Asians and are usually not associated with evidence of CHD. Thus, their value as indicators of CHD is questionable.

Secuencias moleculares de alto y bajo riesgo en enfermedades autoinmunes. Un análisis de la diabetes tipo I en Latinoamérica / High and low risk molecular sequences in autoinmmune diseases. An analysis of type I diabetes in Latin America

La diabetes tipo I es una enfermedad autoinmune, poligénica con una contribución del 48 por ciento de los genes MHC Case II. El objeto de este trabajo es proveer una explicación para las asociaciones moleculares de dichos genes, mediante el análisis de la inmunogenética de 3 poblaciones mestizas de Latinoamérica. Se estudiaron un total de 606 individuos, 349 pacientes con DMDI y 257 sujetos sanos de tres localidades México DF, Caracas, Venezuela, Medellín, Colombia. Los resultados indican que en los grupos mestizos, los haplotipos diabetogénicos son de contribución mediterránea y que la mayoría de los hoplatipos de protección son de origen indígena. Se demostró que las secuencias relevantes en la expresión de la enfermedad están en los loci DRB1 y DQB1, con un aporte mínimo de DQA1 y que las secuencias relevantes en el reconocimiento del péptido y en la inducción de las células Th1 mediadoras de la activación de la respuesta celular, están localizadas en DRB1-57 y 74 (la presencia de ac. aspártico y ac. glutámico confieren resistencia), moduladas por la presencia de D-57 en DQp del antígeno DQ. Estos datos demuestran la participación de DRB1-DQB1 en la enfermedad y abren caminos para un nuevo manejo de la DMDI

Coronary artery disease: an overview of risk factors.

Coronary artery disease (CAD) is an important cause of morbidity and mortality in most industrialized nations, and is gaining in importance as a major disease in developing countries as well. Several risk factors, such as cholesterol, smoking, hypertension, obesity, diabetes, stress and physical activity, have been identified as contributors to the pathogenesis of this disease. Studies done in many countries on South Asian immigrants clearly demonstrate the increased risk for coronary heart disease in this population compared to that of local ethnic groups. Higher prevalence of diabetes, blood pressure, glucose intolerance, insulin resistance, low levels of HDL-cholesterol, high levels of LDL-cholesterol, increased plasma triglycerides and obesity are some of the risk factors identified as contributing to CAD in South Asians. The present report will review briefly the available data on CAD and its pathogenesis with particular emphasis on the problems unique to South Asians.