Mostrando postagens com marcador Salmonella. Mostrar todas as postagens
Mostrando postagens com marcador Salmonella. Mostrar todas as postagens

segunda-feira, 4 de outubro de 2010

PESQUISADORES AMERICANOS DESVENDAM SEGREDO DA SALMONELA

Um grupo de pesquisadores norte-americanos da Universidade da Califórnia (UC Davis) descobriu que a bactéria salmonella enterica desenvolve um ambiente no trato intestinal para favorecer seu crescimento em detrimento das bactérias benéficas ao corpo hospedeiro. 

Segundo estudo publicado na semana passada (23) na revista Nature, a resposta imunológica do organismo humano diante de uma infecção por salmonela, é produzir radicais de oxigênio. A pesquisa aponta que a bactéria consegue utilizar um componente de enxofre (tetrationato), liberado durante a resposta imunológica, no processo de respiração. Vale ressaltar que as bactérias benéficas que residem no trato intestinal utilizam o processo de fermentação para obterem oxigênio e essa “estratégia” oferece mais energia em menos tempo. 

“O corpo humano possui 10 vezes mais células de defesa que bactérias que possam causar doenças” explica Andreas Bäumler, professor de microbiologia e imunologia na UC Davis School of Medicine e principal autor do estudo. “Nós descobrimos um truque ardiloso que permite que a salmonela supere os organismos benéficos do intestino”. 

Para o pesquisador, determinar como a salmonella se reproduz de forma tão eficiente, e superior, às bactérias benéficas é um dos primeiros passos para o desenvolvimento de novos medicamentos para enfrentar as infecções alimentares. 

Clique aqui para acessar o estudo (em inglês) publicado na revista Nature.
http://www.nature.com/nature/journal/v467/n7314/full/nature09415.html


Enviado por Natália Nespolo

segunda-feira, 23 de agosto de 2010

Amplían la retirada nacional de huevos relacionados con la salmonella

Más de 250 personas enfermas con el germen; compañía de Iowa retira 380 millones de huevos


Traducido del inglés: Viernes, 20 de agosto, 2010 

Imagen de noticias HealthDay
JUEVES, 19 de agosto (HealthDay News/HolaDoctor) -- Una compañía de Iowa protagonista de una masiva retirada de huevos relacionados con contaminación por salmonella amplió dramáticamente la retirada nacional el miércoles, hasta alcanzar los 380 millones de huevos.
El brote nacional de salmonella ha enfermado a más de 250 personas en al menos cuatro estados. Las autoridades federales señalan que esta retirada es la más larga de su tipo relacionada con huevos en varios años.
El brote, que aparentemente comenzó en mayo, parece continuar, advirtieron los Centros para el Control y la Prevención de Enfermedades (CDC) de EE. UU. El brote comenzó varias semanas antes de la introducción en julio de nuevas reglas federales de seguridad dirigidas a reducir el riesgo de salmonella en los huevos, reportó el periódico The New York Times.
En una conferencia de prensa del jueves por la tarde, las autoridades federales de salud dijeron que habían recibido casi 2,000 informes de envenenamiento con salmonella entre mayo y julio. Pero las autoridades no podían especificar cuántos de estos casos se relacionaban con esta retirada de huevos.
Sin embargo, se puede esperar más casos de envenenamiento con salmonella debido a huevos infectados, aseguró el Dr. Christopher R. Braden, director en funciones de la División de Enfermedades Transmitidas por los Alimentos, el Agua y el Ambiente de los CDC.
"Creo que tendremos más reportes de enfermedad debido a este brote", apuntó, y citó el periodo que pasa entre que una persona enferma y la enfermedad se reporta a los CDC.
El 13 de agosto, los CDC declararon que "han habido enfermedades confirmadas por Salmonella enteritidis relacionadas con las cáscaras de huevo, y se está investigando su fuente".
El brote ha sido vinculado con huevos enteros de Wright County Egg en Galt, Iowa, que inició la retirada. Sus huevos fueron distribuidos a mayoristas y compañías de comida en todo el país con varios nombres de marca: Lucerne, Albertson, Mountain Dairy, Ralph's, Boomsma's, Sunshine, Hillandale, Trafficanda, Farm Fresh, Shoreland, Lund, Dutch Farms y Kemps.
Según las autoridades estatales de salud, los huevos contaminados con salmonella han enfermado a al menos 266 personas en California, 28 en Colorado y siete en Minnesota. También se han reportado casos sospechosos en Arizona, Illinois, Nevada, Carolina del Norte, Texas y Wisconsin, informó Associated Press.
La retirada incluye huevos enteros empacados entre el 16 de mayo y el 13 de agosto. Vienen en cajas que contienen entre seis y 18 huevos, y que están marcadas con los números de planta P-1026, P-1413 y P-1946. Se debe devolver los huevos, y se recibirá un reembolso.
La Administración de Alimentos y Medicamentos (FDA) de EE.UU. cuenta ahora con equipos en Wright County Egg, señaló la vocera Patricia El-Hinnawy.
"Wright County Egg está cooperando completamente con la investigación de la FDA al implementar esta retirada voluntaria", enfatizó la compañía en una declaración, según ABC News. "Nuestra principal preocupación es evitar que la salmonella llegue a la cadena alimentaria y a los consumidores".
La salmonella puede causar fiebre, calambres abdominales y diarrea, y por lo general dura entre cuatro y siete días.
La FDA aconsejó a los consumidores:
  • Deshacerse de los huevos retirados, o devolverlos a las tiendas para recibir un reembolso.
  • Consultar a un médico si piensa que está enfermo tras comer los huevos retirados.
  • Guardar siempre los huevos en la nevera.
  • Tirar los huevos rotos o sucios.
  • Lavarse las manos, así como los utensilios y superficies de preparación, con agua y jabón tras el contacto con huevos crudos.
  • Cocinar los huevos hasta que tanto la clara como la yema estén firmes, y comerlos rápidamente tras su cocción.
La agencia también advirtió a los consumidores no guardar los huevos al calor o a temperatura ambiente por más de dos horas, y no comer huevos crudos ni platos de restaurante hechos con huevos crudos, poco cocidos o sin pasteurizar.
También se debe evitar comer huevos poco cocidos, sobre todo los niños, los mayores y las personas que tienen sistemas inmunitarios debilitados, o enfermedades que causen debilidad, añadió la agencia.
El New York Times reportó que Wright County Egg ha tenido "enfrentamientos" con los reguladores debido a condiciones laborales malas o poco seguras, violaciones medioambientales, además de contratar inmigrantes ilegales y acosar a los trabajadores.
Hinda Mitchell, vocera de Wright County Egg, afirmó que la compañía había implementado las medidas federales de seguridad requeridas para proteger contra la salmonella en los huevos antes de la fecha límite de julio, según el Times.
Mientras tanto, Umpqua Dairy Products Co. ha retirado algunos productos de leche y bebidas vendidas en Oregón, el suroeste del estado de Washington y el norte de California después de que una cepa de salmonella que enfermó a 23 personas se relacionara con su planta lechera, reportó AP.
El Departamento de Servicios Humanos de Oregón señaló que las pruebas mostraron que 23 residentes de Oregón tenían patrones de ADN correspondientes con la cepa Braenderup de salmonella. El servicio noticioso comentó que dos personas habían sido hospitalizadas.
Las bacterias nocivas como la salmonella son la causa más común de enfermedades transmitidas por los alimentos, según las autoridades federales de salud.

Artículo por HealthDay, traducido por Hispanicare
FUENTES: U.S. Food and Drug Administration; U.S. Centers for Disease Control and Prevention; Associated PressABC NewsUSA TodayThe New York Times; Aug. 19, 2010, news conference, Christopher R. Braden, M.D., acting director of the Division Foodborne, Waterborne and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, the U.S. Centers for Disease Control and Prevention
HealthDay

(c) Derechos de autor 2010, HealthDay


sexta-feira, 20 de agosto de 2010

Egg recall in US grows to half a billion

Via BBC News: http://www.bbc.co.uk/news/world-us-canada-11045557



Half a billion eggs in the US have been recalled in an investigation into a salmonella outbreak, which now includes two farms in the state of Iowa.
Iowa's Hillandale Farms announced it was recalling 170 million eggs after tests confirmed salmonella.
The news follows a recall earlier this week by another Iowa farm that recalled 380 million eggs. An FDA spokeswoman said the two cases are linked.
Food regulators said salmonella cases have increased fourfold since May.

Related stories

About 2,000 salmonella cases were reported between May and July, roughly 1,300 more than usual, the Centers for Disease Control said.
The newest recall from Hillandale Farms applies to eggs sold between April and August.
The salmonella strains causing the illnesses are the same from both farms, according to the Food and Drug Administration.
Hillandale Farms said the eggs were distributed under five different names in 14 US states, while Wright County Egg announced this week the company distributes its product under more than a dozen names.
The recent outbreak could be caused by rodents, shipments of contaminated hens, or tainted feed, says Cornell University microbiology professor Patrick McDonough.

Start Quote

I would anticipate that we will be seeing more illnesses reported likely as a result of this outbreak”
Dr Christopher BradenCenters for Disease Control
Mr McDonough told the Associated Press news agency it is not uncommon for outbreaks to have multiple sources because both farms could have rodent problems or have feed that was contaminated.
Increasing illnesses
Centers for Disease Control (CDC) officials warn that salmonella cases may increase.
"I would anticipate that we will be seeing more illnesses reported likely as a result of this outbreak," said Dr Christopher Braden of the CDC.
Cases that occurred after mid-July may not have been reported yet, Dr Braden told reporters.
But he also said that not all of the roughly 2,000 reported cases of the bacteria-borne disease could be linked to the outbreak.
Hillandale Farms eggs are distributed under the names Sunny Farms, Sunny Meadow, Wholesome Farms, West Creek, and Hillandale Farms.
And Wright County Egg eggs are packaged under the names Lucerne, Albertson, Mountain Dairy, Ralph's, Boomsma's, Sunshine, Hillandale, Trafficanda, Farm Fresh, Shoreland, Lund, Dutch Farms and Kemp.
Salmonella poisoning can be deadly for people with compromised immune systems, but no deaths have so far been reported.
Proper cooking can kill the bacteria, but authorities recommend discarding or returning any potentially affected eggs.
The US Egg Safety Center has information on which eggs US consumers should avoid.

quinta-feira, 12 de agosto de 2010

Dry dog, cat food associated with Salmonella outbreak


Dry dog, cat food associated with Salmonella outbreak

Behravesh CB. Pediatrics. 2010; 126:e1-e7.

A recent outbreak of salmonella highlights the importance of proper handling and storage of pet foods in the home to prevent human illness, especially among young children, according to a published study.
Researchers from the Pennsylvania Department of Health, the Ohio Department of Health, the CDC and the FDA initiated two case control-studies after being alerted to a multistate outbreak of SalmonellaSchwarzengrund during 2007. Questionnaires were used to collect information on people’s contact with animals; the brands of dry dog or cat food purchased; handling and storage of the food and pet-feeding practices.
The first study sought to compare household factors of case-patients with those of controls. Illness was confirmed through laboratory testing, and cases included people who experienced gastrointestinal illnessonset between Jan. 1, 2006, and Aug. 30, 2007.
The second study involved only children aged 2 years and younger who had regular dog contact in either their own homes or at another location. All children included in the study resided in Pennsylvania and were born between Jul. 1, 2005, and Jul. 20, 2007.
CDC researchers noted that 79 people in 21 states were infected with the outbreak strain during the 3-year period, and 48% were aged 2 years or younger. Thirty-eight percent of dog fecal specimens and 9% of dry dog food specimens taken from nine case-households in Pennsylvania contained evidence of the outbreak strain.
Two brands, dubbed A and B, produced by one Pennsylvania manufacturing plant were associated with these cases. Similar results were discovered by researchers in Ohio, although information on where the food was manufactured was unavailable.
In August 2007, the FDA discovered the outbreak strain in two other brands produced at the Pennsylvania plant. Upon inspection, one of 144 swab samples demonstrated contamination with the outbreak strain. Researchers also found evidence of the outbreak strain in more brands manufactured at the same plant in 2008.
Study data indicated a significant link between contact with a dog and Salmonella infection, the researchers noted, and members of case-households were also more likely to have purchased dry dog food, cat food or both manufactured at that particular plant.
The researchers’ findings led to two voluntary recalls of dry dog food, but additional outbreak-related illnesses eventually caused permanent closure of the plant.
“This investigation demonstrated that dry pet food may be contaminated with Salmonella and raises concerns that such contamination could be an underrecognized source of human infections, especially in young children,” wrote the researchers.
PERSPECTIVE
Salmonella ordinarily is a moderate dose enteric pathogen in which 1,000 to 100,000 viable cells must be ingested to produce disease. Secondary spread between people rarely occurs with strains of Salmonellabecause of the dose requirement. Most causes of intestinal salmonellosis involving older children and adults occur secondary to ingestion of contaminated foods where these inoculum sizes can be reached. For infants and young children, Salmonella infection can be acquired through ingestion of low organism doses (<1,000 cells). In the United States, the age group with the highest rate of salmonellosis are the infants < 12 months that result from household cross contamination. The study by Behravesh et al linking human Salmonella infections to contaminated dry dog and cat food show the infectivity of non-typhoid salmonellosis for young children in the household and underscore the potential for household spread of this important pathogen
– Herbert L. DuPont, MD
Infectious Disease News Editorial Board