RESUMEN
Melioidosis in humans presents variably as fulminant sepsis, pneumonia, skin infection and solid organ abscesses. It is caused by Burkholderia pseudomallei, which in the United States is classified as a select agent, with "potential to pose a severe threat to both human and animal health, to plant health or to animal and plant products" (Federal Select Agent Program, http://www.selectagents.gov/, accessed 22 September 2016). Burkholderia pseudomallei is found in soil and surface water in the tropics, especially South-East Asia and northern Australia, where melioidosis is endemic. Human cases are rare in the United States and are usually associated with travel to endemic areas. Burkholderia pseudomallei can also infect animals. We describe a multijurisdictional public health response to a case of subclinical urinary B. pseudomallei infection in a dog that had been adopted into upstate New York from a shelter in Thailand. Investigation disclosed three human contacts with single, low-risk exposures to the dog's urine at his residence, and 16 human contacts with possible exposure to his urine or culture isolates at a veterinary hospital. Contacts were offered various combinations of symptom/fever monitoring, baseline and repeat B. pseudomallei serologic testing, and antibiotic post-exposure prophylaxis, depending on the nature of their exposure and their personal medical histories. The dog's owner accepted recommendations from public health authorities and veterinary clinicians for humane euthanasia. A number of animal rescue organizations actively facilitate adoptions into the United States of shelter dogs from South-East Asia. This may result in importation of B. pseudomallei into almost any community, with implications for human and animal health.
Asunto(s)
Burkholderia pseudomallei/aislamiento & purificación , Enfermedades Transmisibles Importadas/veterinaria , Enfermedades de los Perros/microbiología , Melioidosis/veterinaria , Salud Pública/métodos , Animales , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Burkholderia pseudomallei/inmunología , Enfermedades Transmisibles Importadas/microbiología , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/orina , Perros/microbiología , Humanos , Masculino , Melioidosis/epidemiología , Melioidosis/microbiología , Melioidosis/transmisión , New York/epidemiología , Profilaxis Posexposición , Pruebas Serológicas , Tailandia/epidemiología , ViajeRESUMEN
Changing the potential across the isolated frog gastric mucosa by voltage clamping changes the measured resistance of the tissue in two ways. An immediate change in resistance results from changing the measuring position on the nonlinear current-voltage (I-V) plot. Subsequent to this, the resistance changes slowly with a half-time of about 3 min, a change that is not predicted by a previous model for voltage transients and that implies slow changes in membrane resistance following changes in intracellular ion content. The I-V plot over the range examined shows three breakpoints; changing clamp voltage alters the position of two of these breakpoints as well as the slope of the connecting resistances. The central breakpoint agrees with the potential at zero current and varies with it as the clamp potential is changed, as predicted from a diode model for breakpoint generation.