Nosocomial Transmissibility of Nipah Virus

To the Editor?A severe outbreak of fatal viral encephalitis mainly affecting pig farmers occurred in Malaysia in 1999. The outbreak was due to Nipah virus, a novel paramyxovirus [1]. Nipah virus was isolated from the upper respiratory tract secretions and urine of 8 of 20 patients with acute encephalitis [2]. Mounts et al. [3] found that 3 of 338 health care workers who were exposed to patients during the outbreak were positive for IgG antibodies, as determined by EI A. The 3 positive serum samples did not have an IgM response and were negative for anti-Nipah virus neutralizing antibodies; thus, the authors inferred that the results were likely to be false positives and commented that the lack of nosocomial transmission to the health