Agentes emergentes de importancia zoonótica en caninos en Chile

Las infecciones transmisibles por vectores relacionados a mascotas han generado un creciente interés durantelos últimos años, en especial porque muchos de estos agentes tienen importancia zoonótica. Se resumen acontinuación los principales hallazgos basados en técnicas moleculares (PCR y secuenciación) de un grupode investigación que integra profesionales de medicina humana y veterinaria.Luego del reporte de los primeros casos de ehrlichiosis canina en el país en 1998 en la Región Metropolitana(RM), se identificó Anaplasma platys en sangre de perros con clínica compatible. Su rol patogénico encaninos está bien establecido, pero en humanos hay casos reportados, pero no confirmados con técnicas decerteza. Su vector es Riphicephalus sanguineus, la garrapata más difundida en nuestro país. En Arica se haidentificado recientemente Ehrlichia canis, en un perro con ehrlichiosis clínica. Este agente es causante de lapancitopenia tropical canina y su rol zoonótico ha sido confirmado recientemente.Además, en Chile se ha identificado la presencia de Rickettsia felis, agente del grupo de las fiebresmanchadas, en diferentes especies de pulgas de varias zonas del país, así como también en Riphicephalussanguineus. Si bien en la RM se han documentado clínica y serológicamente casos de rickettsiosis canina, nose ha determinado aún la especie involucrada. A estos agentes se suma el reciente hallazgo de Rickettsiaandaneae, descrita por primera vez en Perú y cuyo rol patogénico aún no ha sido clarificado. En Chile se haencontrado en garrapatas Amblyomma triste y Amblyomma tigrinum extraídas de perros de zonas rurales dediferente zonas del país.  

Immunogenicity and tolerability of an MF59-adjuvanted, egg-derived, A/H1N1 pandemic influenza vaccine in children 6-35 months of age

Background: Vaccines against pandemic A/H1N1 influenza should provide protective immunity in children, because they are at greater risk of disease than adults. This study was conducted to identify the optimal dose of an MF59 (R)-adjuvanted, egg-derived, A/H1N1 influenza vaccine for young children. Methods: Children 6-11 months (N = 144) and 12-35 months (N = 186) of age received vaccine formulations containing either 3.75 mu g antigen with half the standard dose of MF59 or 7.5 mu g antigen with a standard dose of MF59, or a nonadjuvanted formulation containing 15 mu g antigen (children 12-35 months only). Participants were given 2 primary vaccine doses 3 weeks apart, followed by 1 booster dose of MF59-adjuvanted seasonal influenza vaccine 1 year later. Immunogenicity was assessed by hemagglutination inhibition and microneutralization assays. Results: All vaccine formulations were highly immunogenic and met all 3 European licensure criteria after 2 doses. MF59-adjuvanted vaccines met all licensure criteria after 1 dose in both age cohorts, while nonadjuvanted vaccine did not meet all criteria after 1 dose in children 12-35 months. A single booster dose was highly immunogenic, and stable antibody persistence was observed in response to all vaccines. All vaccines were well tolerated. Conclusions: In this study, a single dose of 3.75 mu g antigen with half the standard dose of MF59 was shown to be optimal, providing adequate levels of immediate and long-term antibodies in pediatric subjects 6-35 months of age. These data demonstrated that MF59 adjuvant allowed for reduced antigen content and promoted significant long-term antibody persistence in children, with a satisfactory safety profile

Surveillance System for Infectious Diseases of Pets, Santiago, Chile

Pet diseases may pose risks to human health but are rarely included in surveillance systems. A pilot surveillance system of pet infectious diseases in Santiago, Chile, found that 4 canine and 3 feline diseases accounted for 90.1% and 98.4% of notifications, respectively. Data also suggested association between poverty and pet diseases

Latinamerican guidelines of RIICER for diagnosis of tick-borne rickettsioses

Las rickettsiosis transmitidas por garrapatas son afecciones de distribución mundial, que por diferentes motivos se pueden considerar emergentes y reemergentes. Hasta hace escasos años la única rickettsiosis transmitida por garrapatas en Latinoamérica era la infección por Rickettsia rickettsii, pero en la actualidad y fundamentalmente, gracias a la incorporación de nuevas herramientas para el diagnóstico microbiológico como la reacción en cadena de la polimerasa y secuenciación o el cultivo celular rápido en tubo cerrado, se han descrito e involucrado otras especies de Rickettsia en la producción de patología humana. En estas guías se detallan y describen las diferentes técnicas utilizadas para el diagnóstico microbiológico de las rickettsiosis. Además, se incluye una sección en la que se detallan las especies más importantes de garrapatas duras relacionadas con las rickettsiosis en Latinoamérica, con claves para su clasificación taxonómica.Tick-borne rickettsioses are worldwide infectious diseases that are considered emerging and re-emerging. Until recently the only tick-borne rickettsiosis present in Latin America was Rickettsia rickettsii infection, but to date, with the incorporation of new tools as PCR and sequencing and the quick cellular close tube cultures (Shell-vial), new species has been involved as human pathogens. In these guidelines, we offer an update of the microbiological assays for diagnosing rickettsioses. Besides we have included a section in which the most important hard ticks involved in human rickettsioses in Latinoamerica are detailed.Financiamiento: RIICER (Red Iberoamericana para la Investigación y Control de las Enfermedades Rickettsiales) del Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo (CYTED)

Pet ownership and health status of pets from immunocompromised children, with emphasis in zoonotic diseases

Q4Q4Artículo original205-210Objetive: To characterize pet ownership and pet health status in families of immunocompromised (IS) children, with emphasis in zoonotic diseases. Population and Methods: Families of IS children from two hospitals in San-tiago, Chile, were interviewed and their pets were evaluated by veterinary examination, coproparasitologic and skin dermatophytes test. In specifi c cases, other laboratory tests were performed in IS children or their relatives. Results: 47 out of 70 contacted families had pets, 42 participated in the study. Several risk factors for IS children were observed, as having a turtle as a pet and to clean cat or turtle faeces. Lack of adequate veterinary control, immunizations and deparasitation of pets were observed. Some animals showed zoonotic diseases or agents, as Brucella canis, Cryptosporidium sp, Giardia intestinalis, Toxocaracanis and scabies. 44% of dogs had ticks and 37% had fl eas, both potential vectors of infections. Conclusions: Our results suggest that policies to provide safer pet contact in IS children are needed

Characterization of the humoral and cellular immunity induced by a recombinant BCG vaccine for the respiratory syncytial virus in healthy adults

IntroductionThe human respiratory syncytial virus (hRSV) is responsible for most respiratory tract infections in infants. Even though currently there are no approved hRSV vaccines for newborns or infants, several candidates are being developed. rBCG-N-hRSV is a vaccine candidate previously shown to be safe in a phase I clinical trial in adults (clinicaltrials.gov identifier #NCT03213405). Here, secondary immunogenicity analyses were performed on these samples.MethodsPBMCs isolated from immunized volunteers were stimulated with hRSV or mycobacterial antigens to evaluate cytokines and cytotoxic T cell-derived molecules and the expansion of memory T cell subsets. Complement C1q binding and IgG subclass composition of serum antibodies were assessed.ResultsCompared to levels detected prior to vaccination, perforin-, granzyme B-, and IFN-γ-producing PBMCs responding to stimulus increased after immunization, along with their effector memory response. N-hRSV- and mycobacterial-specific antibodies from rBCG-N-hRSV-immunized subjects bound C1q.ConclusionImmunization with rBCG-N-hRSV induces cellular and humoral immune responses, supporting that rBCG-N-hRSV is immunogenic and safe in healthy individuals.Clinical trial registrationhttps://classic.clinicaltrials.gov/ct2/show/, identifier NCT03213405

Rickettsioses in Latin America, Caribbean, Spain and Portugal

Data on genus and infectious by Rickettsia were retrospectively compiled from the critical review literature regarding all countries in Latin America, Caribbean islands, Portugal and Spain. We considered all Rickettsia records reported for human and/or animal hosts, and/or invertebrate hosts considered being the vector. In a few cases, when no direct detection of a given Rickettsia group or species was available for a given country, the serologic method was considered. A total of 13 Rickettsia species have been recorded in Latin America and the Caribbean. The species with the largest number of country confirmed records were Rickettsia felis (9 countries), R. prowazekii (7 countries), R. typhi (6 countries), R. rickettsii (6 countries), R. amblyommii (5 countries), and R. parkeri (4 countries). The rickettsial records for the Caribbean islands (West Indies) were grouped in only one geographical area. Both R. bellii, R. akari, and Candidatus ‘R. andeane’ have been recorded in only 2 countries each, whereas R. massiliae, R. rhipicephali, R.monteiroi, and R. africae have each been recorded in a single country (in this case, R. africae has been recorded in nine Caribbean Islands). For El Salvador, Honduras, and Nicaragua, no specific Rickettsia has been reported so far, but there have been serological evidence of human or/and animal infection. The following countries remain without any rickettsial records: Belize, Venezuela, Guyana, Surinam, and Paraguay. In addition, except for a few islands, many Caribbean islands remain without records. A total of 12 Rickettsia species have been reported in Spain and Portugal: R. conorii, R. helvetica, R. monacensis, R. felis, R. slovaca, R. raoultii, R. sibirica, R. aeschlimannii, R. rioja, R. massiliae, R. typhi, and R. prowazekii. Amongst these Rickettsia species reported in Spain and Portugal, only R. prowazekii, R. typhi, R. felis, and R. massiliae have also been reported in Latin America. This study summarizes the current state of art on the rickettsial distribution in Latin America, Caribbean, Spain and Portugal. The data obtained allow a better understanding on rickettsial epidemiology and distribution of vector ecology.Reportes del genero Rickettsia y sus asociadas infecciones fueron compilados en una revisión crítica retrospectiva de la literatura científica de los países de Latinoamérica, el Caribe, Portugal y España. Se consideraron todos los reportes para huéspedes humanos y/o animales y también para huéspedes invertebrados los cuales fueron considerados como vectores asociados con Rickettsia. En algunos casos, cuando no existió detección directa a un determinado grupo de rickettsias o especies no disponible en un país, se tuvo en cuenta la detección indirecta por serología. Un total de 13 especies de Rickettsia han sido reportadas en Latinoamérica y el Caribe. Las especies más encontradas en los países fueron: Rickettsia felis (9 países), R. prowazekii (7 países), R. typhi (6 países), R. rickettsii (6 países), R. amblyommii (5 países) y R. parkeri (4 países). Los datos de las islas del Caribe (antillas menores o Indias occidentales), fueron agrupados en una sola área geográfica como un solo país. Ambas R. bellii, R. akari y Candidatus ‘R. andeane’ fueron reportadas en solo 2 países, mientras que R. massiliae, R. rhipicephali, R.monteiroi, y R. africae fueron informadas en un solo país. En este caso R. africae fue reportada en 9 islas de las Antillas menores. Para El Salvador, Honduras y Nicaragua, hasta ahora no se han reportado especies de Rickettsia, pero si evidencia serológica de infección humana y/o animal. Sin reportes de infección por Rickettsia permanecen: Belice, Venezuela, Guayana, Surinam y Paraguay. Además, a excepción de algunas islas del Caribe, muchas de ellas permanecen sin reportes. Un total de 12 especies de Rickettsia han sido documentadas en España y Portugal: R. conorii, R. helvetica, R. monacensis, R. felis, R. slovaca, R. raoultii, R. sibirica, R. aeschlimannii, R. rioja, R. massiliae, R. typhi y R. prowazekii. Entre estas, solamente R. prowazekii, R. typhi, R. felis y R. massiliae han sido documentados en Latinoamérica, España y Portugal. Los datos de este estudio permiten entender mejor la epidemiología de las rickettsias en Latinoamérica, Caribe, España y Portugal, y la distribución de los vectores

Dengue-1 Virus Isolation during First Dengue Fever Outbreak on Easter Island, Chile

Dengue virus was detected for the first time in Chile, in an outbreak of dengue fever on Easter Island. The virus was isolated in tissue culture and characterized by reverse transcription–polymerase chain reaction as being dengue type 1