Measles in Mexico, 1941-2001: interruption of endemic transmission and lessons learned.

In Mexico, measles occurred in a cyclical endemic-epidemic pattern until the early 1970s. Beginning in 1973, routine vaccination augmented by mass vaccination campaigns led to a decrease in the incidence of measles until the 1989-1990 regional pandemic, when the measles attack rate rose to 80 cases per 100000, resulting in 5899 deaths. Since the pandemic, measles elimination efforts in Mexico have resulted in increasing coverage to >95% among children aged 1-6 years with 2 doses of either measles or measles-mumps-rubella vaccine since 1996 and in coverage of 97.6% among children aged 6-10 since 1999. Surveillance data suggest that the transmission of indigenous measles virus was interrupted in 1997. After almost 4 years without measles cases, in April 2000, measles virus was reintroduced into Mexico and 30 laboratory-confirmed cases were reported. Detection of relatively few cases in nonprogrammatic age groups affirms the high immunization coverage and the sensitivity of measles surveillance in Mexico. We conclude that the specific strategies adopted for measles elimination have enabled Mexico to eliminate the endemic transmission of measles.

The U.S.-Mexico Border Infectious Disease Surveillance project: establishing bi-national border surveillance.

In 1997, the Centers for Disease Control and Prevention, the Mexican Secretariat of Health, and border health officials began the development of the Border Infectious Disease Surveillance (BIDS) project, a surveillance system for infectious diseases along the U.S.-Mexico border. During a 3-year period, a binational team implemented an active, sentinel surveillance system for hepatitis and febrile exanthems at 13 clinical sites. The network developed surveillance protocols, trained nine surveillance coordinators, established serologic testing at four Mexican border laboratories, and created agreements for data sharing and notification of selected diseases and outbreaks. BIDS facilitated investigations of dengue fever in Texas-Tamaulipas and measles in California-Baja California. BIDS demonstrates that a binational effort with local, state, and federal participation can create a regional surveillance system that crosses an international border. Reducing administrative, infrastructure, and political barriers to cross-border public health collaboration will enhance the effectiveness of disease prevention projects such as BIDS.

Hipertensión arterial en México: Resultados de la Encuesta Nacional de Salud (ENSA) 2000 / Arterial hypertension in Mexico: results of the National Health Survey 2000

AIMS: Hypertension remains as a major cause of cardiovascular morbidity in MÚxico. The Health National Survey 2000 of MÚxico was performed to analyze the current status of the prevalence of some risk factors such as diabetes, hypertension (HTA), obesity, smoking, and proteinuria. METHODS: A National Survey was carried out in MÚxico where 45,300 individuals between 20 to 69-y.o. were screened. The estimated sample size was calculated considering the total number of persons into the mentioned age; a minimal prevalence of 6 of the included risk factors, at a significance level of 0.05; a maximum relative error of 0.145, and a rate of response of at least 70. Diagnosis of HTA was accepted in: previous medical diagnosis with prescription of antihypertensive drugs, or high blood pressure (> or = 140/90 mmHg) detected during the interview. Data were adjusted for the national distribution of age-groups and gender (established in 2000, INEGI). RESULTS: 38,377 (98.8) individuals were correctly screened for blood pressure. The prevalence of hypertension in MÚxico was 30.05 (34.2 in men and 26.3 in women). The prevalence was directly related with age and gender. The percentage of mexicans with HTA after 50-y.o. is > 50. The prevalence was greater in women after 50-y.o. Among persons with hypertension, treatment was detected in 46 and approximately 20 of them were controlled (< 140/90 mmHg). The percentage of mexicans with HTA who were unaware that they have high blood pressure was 61. The total percentage of HTA controlled was 14.6. The North states had the greater prevalence (approximately 34) of HTA while South states had the lower prevalence (27). The odds ratio (age/sex-adjusted) for HTA were: for diabetes 1.54(CI95, 1.44-1.63); for obesity 2.3 (CI 95, 2.22-2.43); for smoking 1.26 (CI 95, 1.21-1.32). For proteinuria subjects, 40 had HTA. CONCLUSIONS: Around 15 millions of mexicans between 20 to 69-y.o. had hypertension, 60 of them are unaware. The prevalence of hypertension in MÚxico (30.05) has increased. Among persons with hypertension -15 are controlled. The North of MÚxico has the higher prevalence of hypertension. Diabetes, smoking, and obesity increase the risk of hypertension. The 2000 National Survey of Health shows the epidemiological trend in several important chronic diseases in MÚxico and declare an urgent need of new strategies for detection, control and treatment of hypertension.