Epidemiology

The outbreak of NiV encephalitis began in September 1998 in Malaysia and subsequently spread to other regions of pig farming and then to Singapore. The outbreak was preceded by a respiratory illness in pigs and was originally thought related to Japanese encephalitis virus (JEV). However, the infection did not abate with mosquito control measures and JEV vaccination strategies, and all but a few persons were seronegative for anti-JEV IgM antibodies.1-1-1 The 265 reported human cases likely represent an underestimate of the total number of human infections. The number of infected individuals who experienced asymptomatic seroconversion or became only mildly ill is not precisely known.[2] Asymptomatic infection was serologically identified in 6-17% of those tested in a case-control study evaluating risk factors for NiV infection.[3] Epidemiological studies revealed that the primary risk for transmission to humans was exposure to sick pigs or fresh pig products. Only 8% of persons with

NiV encephalitis had no reported contact with sick pigs, pig urine, or feces.[3] An additional risk factor included employment as an abattoir worker; however, employment as a pork seller or being part of the military effort responsible for culling pigs as part of an eradication campaign carried low risk for acquisition of infection. Human to human transmission was thought to be

uncommon/ ]

Based on similarities to Hendra virus (HeV), a related Henipavirus, flying foxes (fruit bats) were evaluated as a natural reservoir of NiV. The presence of neutralizing antibodies against NiV was detected mainly in Island flying foxes (Pteropus hypomelanus) and Malayan flying foxes (Pteropus vampyrus), and NiV has been detected in the urine of Island flying foxes.[5] Neutralizing antibodies have not been routinely found in other animal species. These observations led to the hypothesis that pigs acquire the virus by consuming fruits partially eaten by bats that release the virus in their secretions.[2] Infection in humans is thought to be a dead-end infection.

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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