Este artículo no tiene resumen

La República de Haití con 9 millones de habitantes vive desde antaño una gran debilidad en varios frentes, pero en especial, en aspectos concernientes a la salud y a los servicios públicos que además de ser precarios solo alcanzan para una pequeña parte de la población. Terremotos, inundaciones y huracanes sumados a una eterna inestabilidad social y a una magra cobertura de salud llevan a panoramas ominosos como la actual epidemia de cólera del que solo se saldrá cuando se dejen de buscar culpables y se mancomunen el gobierno, ONGs y Naciones Unidas para controlar la epidemia y sentar bases sólidas de salubridad y protección social.

OBJECTIVES:

Recent large cholera outbreaks highlight the need for improved understanding of the pathogenesis and epidemiology of cholera. The incubation period of cholera has important implications for clinical and public health decision-making, yet statements of the incubation period of cholera are often imprecise. Here we characterize the distribution of cholera's incubation period.

METHODS:

We conducted a systematic review of the literature for statements of the incubation period of cholera and data that might aid in its estimation. We extracted individual-level data, parametrically estimated the distribution of toxigenic cholera's incubation period, and evaluated evidence for differences between strains.

RESULTS:

The incubation period did not differ by a clinically significant margin between strains (except O1 El Tor Ogawa). We estimate the median incubation period of toxigenic cholera to be 1.4 days (95% CI, 1.3-1.6). Five percent of cholera cases will develop symptoms by 0.5 days (95% CI 0.4-0.5), and 95% by 4.4 days (95% CI 3.9-5.0) after infection.

CONCLUSIONS:

We recommend that cholera investigations use a recall period of at least five days to capture relevant exposures; significantly longer than recent risk factor studies from the Haitian epidemic. This characterization of cholera's incubation period can help improve clinical and public health practice and advance epidemiologic research.

In a controlled field trial on some 584 000 people in an endemic cholera El Tor area in the Philippines, it was demonstrated that cholera vaccines gave moderate protection of short duration. Injection of a single dose of vaccine prepared from either Vibrio cholerae or Vibrio El Tor gave over 50% protection for the first two months. The immunity conferred by the V. cholerae vaccine rapidly declined after three to four months. The V. El Tor vaccine gave protection for six months, but its effectiveness declined. An oil-adjuvant vaccine prepared from V. cholerae conferred an increasing degree of protection of long duration, but, owing to severe vaccination reactions, its use could not be recommended.

El cólera en nuestro país ha generado importantes problemas de salud pública. Actualmente es tratado recuperando el volumen perdido y eliminando el V. cholerae mas no bloqueando la acción de la toxina. Existen evidencias que la Nicotinamida actuaría sobre la toxina disminuyendo la secreción de agua y electrólitos. Se evaluó la capacidad de la Nicotinamida para reducir la pérdida de fluidos en conejos con cólera; utilizando un estudio experimental aleatorizado. Se administró nicotinamida a 10 conejos sanos, cuantificando sus excretas (g/día), pre y post administración para descartar efectos que alteren la interpretación de los resultados; no se halló diferencias estadísticamente significativas (p=0,3). Luego de 5 días, para asegurar la eliminación del fármaco, se infectó a los conejos dividiendolos en 2 grupos de 5; al presentarse la diarrea administramos Nicotinamida y placebo respectivamentes, cuantificamos las deposiciones (g/día) hallando diferencia estadísticamente significativa (p<0,001); demostramos que la Nicotinamida disminuye la pérdida de fluidos en cólera; abriendo una nueva posibilidad terapéutica.

Tetracycline continues to be an effective antimicrobial agent in the clinical control of cholera but because of its high cost, relatively short shelf-life and recent reports of increased resistance of vibrios to tetracycline in vitro, alternative antimicrobial agents have been tested. Furazolidone, effective against cholera caused by the El Tor biotype in adults, was found to be as effective as tetracycline in reducing the volume and duration of diarrhoea in children with classical cholera and, given over a period of 7 days, only slightly less effective in reducing duration of vibrio excretion.Therapy with an antimicrobial agent over a period of 7 days was associated with a significantly smaller rise in vibriocidal antibody titre (of no clinical significance) in the youngest age-group studied; this was probably due to a diminished antigenic stimulus from the primary infection. Undernourished children showed a poorer response to anti-microbial therapy.The study indicated that furazolidone is a reasonable alternative to tetracycline in the treatment of cholera.

Este artículo no tiene resumen

Este artículo no tiene resumen

A controlled field trial on some 584 000 people in an endemic cholera El Tor area in the Philippines demonstrated that cholera vaccines gave moderate protection of short duration. Injection of a single dose of vaccine prepared from either Vibrio cholerae or El Tor vibrios gave over 50% protection for the first 2 months. The immunity conferred by the V. cholerae vaccine declined rapidly after 3 to 4 months. The effectiveness of the El Tor vaccine continued for 6 months. An oil-adjuvant vaccine prepared from V. cholerae conferred an equally high degree of protection for a longer period of time, but, owing to severe vaccination reactions, its use could not be recommended.

To assess the effectiveness of cholera vaccines, 2 controlled field trials were made in Calcutta-an endemic area-during 1964 and 1965. Three Indian vaccines of which 1 was grown on casein hydrolysate and 2 on agar, a freeze-dried vaccine from the Walter Reed Army Institute of Research (WRAIR), Washington, D.C., and an El Tor vaccine from the Philippines were used, with typhoid-paratyphoid (TAB) vaccine as a control. The 210 112 volunteers were vaccinated subcutaneously with a single dose of one of the vaccines.In the 1964 trial, the number of bacteriologically confirmed cases was not enough to show statistically significant differences in incidence between the 5 vaccine groups and the control group. However, the WRAIR freeze-dried vaccine protected about 40% of the vaccinees for 6 months after vaccination, although the efficacy was higher (57%) during the first 3 months than during the subsequent 3 months (28%). Agar-grown vaccine, produced by the Central Research Institute, Kasauli, was 37% efficacious.In the 1965 trial, owing to the small number of cases in the study area, the Kasauli vaccine was the only one to show statistically significant protection (40%).