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.

[Organizational decision making in health: the case of dengue]. / Las organizaciones inteligentes en la toma de decisiones en salud: el caso del dengue.

Intelligent organizations (IO) represent a valuable tool to organize and guide dengue fever surveillance, prevention and control interventions. IO entail state of the art technology in managerial science to generate behavioral frameworks of organizational structures and policies. They present a systematic description of problems and construct computerized models to develop systemic thinking; they produce a shared vision and build progressive mental learning and advancement models. Also, IO promote team building and personal control skills. Scientific-technological advances have produced a wealth of information in medicine, with the corresponding growth of organizations and difficulty of responses because of sudden and incessant change. This new environment calls for the application of IO know-how. This article is oriented to prove the usefulness of the IO technology in the ordering and systematization of the reports about the medical sciences facts. Dengue was chosen to exemplify the use of IO technology as it represents an increasing health problem in America, as well as in Mexico; it is so complex that it can evolve to a more serious problem, besides it can be analyzed within a systemic method.

Variation in Aedes aegypti larval indices over a one year period in a neighborhood of Mérida, Yucatán, México.

Surveys for Aedes aegypti larvae were conducted to provide an estimate of the magnitude and timing of seasonal variations in larval indices in one colonia in Mérida, Yucatán, México, and to assess how the proportion of disposable and non-disposable containers as larval production sites varies. Breteau indices exceeded 200 during the months of July and August, and disposable containers were important year-round larval production sites.