Outbreak of Group A beta hemolytic Streptococcus pharyngitis in a Peruvian military facility, April 2012.

Group A Streptococcus (GAS), or Streptococcus pyogenes, is a common cause of acute pharyngitis as well as other diseases. Closed populations such as those living on military bases, nursing homes, and prisons are particularly vulnerable to GAS outbreaks due to crowding that facilitates person-to-person transmission. This report details a large outbreak of GAS pharyngitis at a Peruvian military training facility near Lima, Peru, in April 2012. Initial findings showed 145 cases. However, as the investigation continued it was revealed that some trainees may have concealed their illness to avoid real or perceived negative consequences of seeking medical care. A subsequent anonymous survey of all trainees revealed at least 383 cases of pharyngitis among the facility's 1,549 trainees and an attack rate of 34 percent among the 1,137 respondents. The epidemic curve revealed a pattern consistent with routine person-to-person transmission, although a point-source initiating event could not be excluded. Laboratory results showed GAS emm type 80.1 to be the culprit pathogen, an organism not commonly implicated in outbreaks of GAS in the Americas. Barious unique and illustrative features of outbreak investigation in military facilities and populations are discussed.

A high diversity of Eurasian lineage low pathogenicity avian influenza A viruses circulate among wild birds sampled in Egypt.

Surveillance for influenza A viruses in wild birds has increased substantially as part of efforts to control the global movement of highly pathogenic avian influenza A (H5N1) virus. Studies conducted in Egypt from 2003 to 2007 to monitor birds for H5N1 identified multiple subtypes of low pathogenicity avian influenza A viruses isolated primarily from migratory waterfowl collected in the Nile Delta. Phylogenetic analysis of 28 viral genomes was performed to estimate their nearest ancestors and identify possible reassortants. Migratory flyway patterns were included in the analysis to assess gene flow between overlapping flyways. Overall, the viruses were most closely related to Eurasian, African and/or Central Asian lineage low pathogenicity viruses and belonged to 15 different subtypes. A subset of the internal genes seemed to originate from specific flyways (Black Sea-Mediterranean, East African-West Asian). The remaining genes were derived from a mixture of viruses broadly distributed across as many as 4 different flyways suggesting the importance of the Nile Delta for virus dispersal. Molecular clock date estimates suggested that the time to the nearest common ancestor of all viruses analyzed ranged from 5 to 10 years, indicating frequent genetic exchange with viruses sampled elsewhere. The intersection of multiple migratory bird flyways and the resulting diversity of influenza virus gene lineages in the Nile Delta create conditions favoring reassortment, as evident from the gene constellations identified by this study. In conclusion, we present for the first time a comprehensive phylogenetic analysis of full genome sequences from low pathogenic avian influenza viruses circulating in Egypt, underscoring the significance of the region for viral reassortment and the potential emergence of novel avian influenza A viruses, as well as representing a highly diverse influenza A virus gene pool that merits continued monitoring.

Rabies virus related to vampire bats (Desmodus rotundus) isolated from a crab-eating fox (Cerdocyon thous) in Southeast Brazil

In this study, rabies virus was isolated from a naturally infected crab-eating fox [Cerdocyon thous] in a rural area of São Paulo State, Brazil. The sample was positive for the standard techniques used for rabies diagnosis. The isolate was antigenically characterized using anti-nucleoprotein monoclonal antibodies. Studies on molecular epidemiology by patterns of nucleotide substitution in the nucleoprotein gene showed that the isolate was genetically homologous to the rabies variant maintained and transmitted by the common vampire bat Desmodus rotundus. This is the first report of detection of this variant from a crab-eating fox in Brazil and represents evidence of cross-species transmission. This was the unique report where this variant was isolated from a crab eating fox in Brazil.

Rabies virus maintained by dogs in humans and terrestrial wildlife, Ceará State, Brazil.

Rabies viruses circulating in Ceará, Brazil, were identified by molecular analysis to be related to variants maintained by dogs, bats, and other wildlife. Most of these viruses are associated with human rabies cases. We document the emergence of a rabies virus variant responsible for an independent epidemic cycle in the crab-eating fox (Cerdocyon thous).

First case of human rabies in chile caused by an insectivorous bat virus variant.

The first human rabies case in Chile since 1972 occurred in March 1996 in a patient without history of known exposure. Antigenic and genetic characterization of the rabies isolate indicated that its reservoir was the insectivorous bat Tadarida brasiliensis. This is the first human rabies case caused by an insectivorous bat rabies virus variant reported in Latin America.

Aislamiento y caracterización molecular de un virus rábico, obtenido de un murciélago no hematófago en la ciudad de México / Isolation and molecular characterization of rabies virus from a non-hematophagous bat in Mexico City

El objetivo de este estudio fue caracterizar antigénica y genéticamente un aislamiento del virus de la rabia obtenido de un murciélago insectívoro (Tadarida brasiliensis) encontrado en la ciudad de México en 1995. Al momento de la captura, el animal presentaba incoordinación de miembros, pelo hirsuto y debilidad general. El murciélago fue positivo a la prueba de inmunofluorescencia directa para el diagnóstico de rabia. Para la caracterización antigénica se efectuó un panel de ocho anticuerpos monoclonales dirigidos contra la nucleocápside viral, mediante la técnica de inmunofluorescencia indirecta. Como testigo se usó una muestra positiva a rabia proveniente de un bovino agredido por un murciélago vampiro (Desmodus rotundus). La tipificación genética se realizó a través del secuenciado de una posición del ADN complementario de la nucleoproteína viral, comprendida entre las posiciones 1094 y 1413. Para los estudios genéticos comparativos se aplicaron los programas PilUp y Distances Programa Genetic Computer Group (GCG) versión 8.1. La caracterización antigénica determinó que el virus aislado del Tadarida brasiliensis pertenecía a la variante antigénica 9 y el testigo a la variante 3. Esta última se encuentra distribuida en toda América Latina y su reservorio es el Desmodus rotundus. La caracterización genética demostró que la muestra problema compartía un porcentaje de homología del 91.7 por ciento con el testigo, pero siendo altamente homóloga (99.7 por ciento) a aislamientos obtenidos de Tadarida brasiliensis en Estados Unidos de América. Esto último sugiere la posible presencia de ciclos endémicos del virus de la rabia en las poblaciones de estos murciélagos en México. La alta diversidad y densidad de murciélagos en el país, así como los resultados obtenidos en este estudio, enfatizan la necesidad de efectuar investigaciones más detalladas acerca del papel que juegan los murciélagos no hematófagos en la epidemiología de la rabia en México.