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Virulence of infectious pathogens can be unstable and evolve rapidly depending on the evolutionary dynamics of the organism. Experimental evolution can be used to characterize pathogen evolution, often with the underlying objective of understanding evolution of virulence. We used experimental evolution techniques (serial transfer experiments) to investigate differential growth and virulence of Batrachochytrium dendrobatidis (Bd), a fungal pathogen that causes amphibian chytridiomycosis. We tested two lineages of Bd that were derived from a single cryo-archived isolate; one lineage (P10) was passaged 10 times, whereas the second lineage (P50) was passaged 50 times. We quantified time to zoospore release, maximum zoospore densities, and timing of zoospore activity and then modeled population growth rates. We also conducted exposure experiments with a susceptible amphibian species, the common green tree frog (Litoria caerulea) to test the differential pathogenicity. We found that the P50 lineage had shorter time to zoospore production (T min ), faster rate of sporangia death (d s ), and an overall greater intrinsic population growth rate (λ). These patterns of population growth in vitro corresponded with higher prevalence and intensities of infection in exposed Litoria caerulea, although the differences were not significant. Our results corroborate studies that suggest that Bd may be able to evolve relatively rapidly. Our findings also challenge the general assumption that pathogens will always attenuate in culture because shifts in Bd virulence may depend on laboratory culturing practices. These findings have practical implications for the laboratory maintenance of Bd isolates and underscore the importance of understanding the evolution of virulence in amphibian chytridiomycosis.

Objective To determine how, during the 2013-2016 Ebola outbreak in western Africa, States Parties to the World Health Organization's (WHO) 2005 International Health Regulations (IHR) followed the IHR's international travel recommendations. Methods In 2015, we used the Google search engine to investigate the 196 States Parties to the 2005 IHR. Information detailing Ebolarelated travel regulations or restrictions of each State Party was sourced first from official government websites and then from travel and news websites. When limited, conflicting or no relevant information was found on a government website, an email inquiry was sent to a corresponding embassy in an Anglophone country. Findings We collected relevant and non-conflicting data for each of 187 States Parties. Of these, 43 (23.0%) prohibited the entry of foreigners who had recently visited a country with widespread Ebola transmission and another 15 (8.0%) imposed other substantial restrictions on such travellers: the requirement to produce a medical certificate documenting no infection with Ebola (n=8), mandatory quarantine (n = 6) or other restrictions (n = 1). Conclusion In responding to the 2013-2016 Ebola outbreak, countries had variable levels of adoption of the 2005 IHR's international travel recommendations. We identified 58 (31.0%) States Parties that exceeded or disregarded the recommendations.There is a need for more research to understand and minimize deviations from such recommendations. Objectif Determiner comment, lors de la flambee de maladie a virus Ebola qui a sevi de 2013 a 2016 en Afrique de l'Ouest, les Etats parties au Reglement sanitaire international (RSI) de 2005 de l'Organisation mondiale de la Sante (OMS) ont suivi les recommandations du RSI concernant les voyages Internationaux. Methodes En 2015, nous avons utilise le moteur de recherche Google pour mener une enquete sur les 196 Etats parties au RSI de 2005. Nous avons d'abord recherche des informations sur la reglementation ou les restrictions relatives aux voyages appliquees par chaque Etat partie pour faire face a la flambee de maladie a virus Ebola sur les sites Internet officiels des gouvernements, puis sur des sites Internet de voyage et d'information. Lorsque les informations disponibles sur le site Internet d'un gouvernement etalent insuffisantes, contradictoires ou non pertinentes, une demande a ete envoyee par e-mail a l'ambassade correspondante dans un pays anglophone. Resultats Nous avons recueilli des donnees pertinentes et non contradictoires sur 187 Etats parties. Sur ces 187 Etats parties, 43 (23,0%) ont interdit l'entree sur leur territoire aux etrangers ayant recemment sejourne dans un pays oU la transmission de la maladie a virus Ebola prenait une ampleur considerable et 15 (8,0%) ont impose d'autres restrictions importantes a ce type de voyageurs: presentation obligatoire d'un certificat medical attestant que le voyageur n'est pas infecte par le virus Ebola (n=8), quarantaine obligatoire (n=6) ou autres restrictions (n= 1). Conclusion Face a la flambee de maladie a virus Ebola qui a sevi entre 2013 et 2016, les pays ont adopte a differents niveaux les recommandations du RSI de 2005 concernant les voyages Internationaux. Nous avons repere 58 (31,0%) Etats parties ayant depasse ou ignore les recommandations. Il est necessaire de mener davantage de recherches pour comprendre et reduire les entorses faites a ces recommandations. Objetivo Determinar como los Estados Partes del Reglamento Sanitario Internacional (RSI) de la Organizacion Mundial de la Salud (OMS) siguieron las recomendaciones sobre viajes Internacionales del RSI de 2005 durante el brote de ebola en el oeste africano entre 2013 y 2016. Metodos En 2015, se utilizo el motor de busqueda de Google para investigar los 196 Estados Partes del RSI de 2005. La Informacion que detallaba los reglamentos sobre viajes relacionados con el ebola o las restricciones de cada Estado Parte se obtuvo primero de los sitios web gubernamentales oficiales y, posteriormente, de sitios web sobre viajes y noticias. Cuando la informacion era escasa, contradictoria o no se encontraba en el sitio web gubernamental, se enviaba un correo electronico de solicitud a la embajada correspondiente de un pais anglopa riante. Resultados Se recopilaron datos importantes y coherentes de 187 Estados Partes. Entre ellos, 43 (23,0%) prohibieron la entrada de extranjeros que habian visitado recientemente un pais con un nivel generalizado de contagio del ebola y otros 15 (8,0%) impusieron otras restricciones importantes para dichos viajeros: el requisito de obtener un certificado medico que documentara que el individuo no estaba infectado con el virus (n = 8), cuarentena obligatoria (n=6) u otras restricciones (n = 1). Conclusion Como respuesta al brote de ebola entre 2013 y 2016, los paises contaban con distintos niveles de adopcion de las recomendaciones sobre viajes internacionales del RSI de 2005. Se identificaron 58 (31,0%) Estados Partes que superaron o incumplieron las recomendaciones. Existe la necesidad de una busqueda mas exhaustiva para comprendery minimizar los incumplimientos de dichas recomendaciones., Introduction Ebola virus disease--previously known as Ebola haemorrhagic fever--was first identified in 1976 in Zaire--the country now known as the Democratic Republic of Congo. (1) The disease is severe and [...]

OBJECTIVE: To study a novel surveillance system introduced in Mpumalanga Province, a rural area in the north-east of South Africa, in an attempt to address deficiences in the system of notification for infectious conditions that have the potential for causing outbreaks. METHODS: Hospital-based infection control nurses in all of Mpumalanga?s 32 public and private hospitals were trained to recognize, report, and respond to nine clinical syndromes that require immediate action. Sustainability of the system was assured through a schedule of regular training and networking, and by providing feedback to the nurses. The system was evaluated by formal review of hospital records, evidence of the effective containment of a cholera outbreak, and assessment of the speed and appropriateness of responses to other syndromes. FINDINGS: Rapid detection, reporting and response to six imported cholera cases resulted in effective containment, with only 19 proven secondary cholera cases, during the two-year review period. No secondary cases followed detection and prompt response to 14 patients with meningococcal disease. By the end of the first year of implementation, all facilities were providing weekly zero-reports on the nine syndromes before the designated time. Formal hospital record review for cases of acute flaccid paralysis endorsed the value of the system. CONCLUSION: The primary goal of an outbreak surveillance system is to ensure timely recognition of syndromes requiring an immediate response. Infection control nurses in Mpumalanga hospitals have excelled in timely weekly zero-reporting, participation at monthly training and feedback sessions, detection of priority clinical syndromes, and prompt appropriate response. This review provides support for the role of hospital-based nurses as valuable sentinel surveillance agents providing timely data for action.

Objective To examine the level of stated compliance with public health pandemic influenza control measures and explore factors influencing cooperation for pandemic influenza control in Australia. Methods A computer-assisted telephone interview survey was conducted by professional interviewers to collect information on the Australian public&apos;s knowledge of pandemic influenza and willingness to comply with public health control measures. The sample was randomly selected using an electronic database and printed telephone directories to ensure sample representativeness from all Australian states and territories. After we described pandemic influenza to the respondents to ensure they understood the significance of the issue, the questions on compliance were repeated and changes in responses were analysed with McNemar&apos;s test for paired data. Findings Only 23% of the 1166 respondents demonstrated a clear understanding of the term "pandemic influenza". Of those interviewed, 94.1% reported being willing to comply with home quarantine; 94.2%, to avoid public events; and 90.7%, to postpone social gatherings. After we explained the meaning of "pandemic" to interviewees, stated compliance increased significantly (to 97.5%, 98.3% and 97.2% respectively). Those who reported being unfamiliar with the term "pandemic influenza," male respondents and employed people not able to work from home were less willing to comply. Conclusion In Australia, should the threat arise, compliance with containment measures against pandemic influenza is likely to be high, yet it could be further enhanced through a public education programme conveying just a few key messages. A basic understanding of pandemic influenza is associated with stated willingness to comply with containment measures. Investing now in promoting measures to prepare for a pandemic or other health emergency will have considerable value. Une traduction en francais de ce resume figure a la fin de l&apos;article. Al final del articulo se facilita una traduccion al espanol. Objectif Etudier le niveau d&apos;observance declare des mesures de sante publique contre la grippe pandemique et les facteurs influant sur la cooperation des Australiens a l&apos;endiguement de cette maladie. Methodes Une enquete par entretien telephonique assistee par ordinateur a ete menee par des enqueteurs professionnels pour recueillir des informations sur les connaissances de la population australienne au sujet de la grippe pandemique et sur sa volonte de respecter les mesures de sante publique contre cette grippe. L&apos;echantillon a ete randomise en utilisant une base de donnees electronique et des annuaires telephoniques imprimes pour garantir la representativite de cet echantillon a l&apos;egard de tousles Etats et tousles territoires australiens. Apres avoir explique aux personnes interrogees ce qu&apos;est la grippe pandemique pour s&apos;assurer qu&apos;elles comprennent l&apos;importance du probleme, nous avons repete les questions relatives a l&apos;observance des mesures et nous avons analyse les variations des reponses par le test de McNemar pour donnees appariees. Resultats 23 % seulement des 1166 personnes interrogees ont manifeste une comprehension claire du terme << grippe pandemique >>. Parmi les personnes interrogees, 94,1% ont indique qu&apos;elles etaient disposees a respecter la quarantaine a domicile, 94,2 % qu&apos;elles eviteraient les evenements publics et 90,7 % qu&apos;elles differeraient les rassemblements sociaux. Apres explication du terme << grippe pandemique >> aux sujets de l&apos;enquete, l&apos;observance declaree a augmente significativement (pour atteindre respectivement 97,5 %, 98,3 % et 97,2 %). Les personnes ayant indique ne pas etre familiarisees avec ce terme, les sujets de sexe masculin et les employes ne pouvant travailler a leur domicile ont manifeste une moindre disposition a respecter les mesures. Conclusion En Australie, si la menace se concretisait, l&apos;observance des mesures d&apos;endiguement contre la grippe pandemique serait probablement bonne, bien qu&apos;elle puisse encore etre amelioree par un programme d&apos;education du public vehiculant juste quelques messages cles. Une comprehension generale de la notion de grippe pandemique est associee a d&apos;une volonte declaree de respecter les mesures d&apos;endiguement. Il y aurait un interet considerable a investir maintenant dans la promotion de mesures pour se preparer a une pandemie ou autre urgence de sante publique. Objetivo Determinar el grado de cumplimiento declarado de las medidas de salud publica contra la gripe pandemica y estudiar los factores que influyen en la cooperacion necesaria para controlar esa pandemia en Australia. Metodos Entrevistadores profesionales llevaron a cabo una encuesta telefonica asistida por ordenador a fin de reunir informacion sobre los conocimientos del publico australiano acerca de la gripe pandemica y su determinacion de observar las medidas de salud publica adoptadas para controlarla. La muestra fue seleccionada aleatoriamente a partir de una base de datos electronica y de guias telefonicas impresas para procurar que fuese representativa de todos los estados y territorios australianos. Tras explicar a los encuestados en que consiste la gripe pandemica para que entendieran la importancia del tema, se repitieron las preguntas sobre el cumplimiento. La variacion sufrida por las respuestas fue analizada mediante la prueba de McNemar para datos apareados. Resultados Solo un 23% de los 1166 encuestados demostraron comprender cabalmente Io que supone una << gripe pandemica >>. Entre los entrevistados, un 94,1% manifesto estar dispuesto a cumplir una cuarentena domiciliaria; et 94,2%, a evitar actos publicos; y el 90,7%, a aplazar encuentros sociales. Despues de haber explicado a los entrevistados el significado del termino << pandemia >>, el cumplimiento declarado aumentoi significativamente (al 97,5%, 98,3% y 97,2% respectivamente). Los que manifestaron no conocer bien el significado de la expresion << gripe pandemica, >> los encuestados varones y los empleados que no podian trabajar desde su domicilio se mostraron mas reacios a seguir las recomendaciones. Conclusion En Australia, si se materializase la amenaza, el cumplimiento de las medidas de contencion contra la gripe pandemica seria probablemente alto, no obstante lo cual podria mejorarse mediante un programa de educacion del publico que transmitiera simpiemente unos cuantos mensajes clave. Unos conocimientos basicos sobre la gripe pandemica se asocian a la voluntad declarada de cumplir las medidas de contencion. Invertir ahora en promover medidas de preparacion para una pandemia u otra emergencia sanitaria constituye una opcion beneficiosa., Introduction To limit the spread of disease during the early containment phase of an influenza pandemic response, WHO recommends the use of non-pharmaceutical interventions (NPIs), including public education, social distancing, [...]

The sudden appearance of chytridiomycosis, the cause of amphibian deaths and population declines in several continents, suggests that its etiologic agent, the amphibian chytrid Batrachochytrium dendrobatidis, was introduced into the [...]

Background: The control of head lice is frequently based on perceptions rather than evidence, as illustrated by the belief that vacuuming carpets is an essential component of treating head lice, and the less common practice of application of insecticides to floors as an adjunct to head lice treatment. Objective: To 1) evaluate the importance of floors as a source of infection for head lice in primary schools to provide evidence on which to base decisions about the need to treat floors; 2) determine the prevalence of active pediculosis and average intensity of infection in primary school children in Townsville, north Queensland. Methods: In Townsville, north Queensland, we examined preschool and primary classroom floors for lice by using a filter on a vacuum cleaner when the children were absent from the rooms. Active pediculosis was treated, head lice were collected and counted. Results: Of the 2,230 children examined from 118 classrooms, 466 had head lice, a prevalence of 20.9%. A total of 14,033 lice were collected from these children to give an average intensity of infection of 30.1 (95% CI 21.9-38.3) lice per infected child and 129.9 (95% CI 90.7-169.2) lice per infected class. Of the 118 classrooms, 108 (91.5%) had at least one child with active pediculosis. No lice were recovered from the classroom floors. Conclusion: Classroom floors are not a risk in the transmission of head lice and no special anti-louse measures are required.

This review presents data on two newly emerging chytridiomycosis and ranaviral wildlife infectious diseases and their impact on the global decline of amphibian populations. Amphibians affected are the golden toad of Costa Rica and seven Australian species including gastric-brooding frogs., We review recent research on the pathology, ecology, and biogeography of two emerging infectious wildlife diseases, chytridiomycosis and ranaviral disease, in the context of host-parasite population biology. We examine the [...]

In the mid-1990s, Hendra virus (HeV) emerged as a new pathogen that spilled over from bats to horses to humans (1,2). All 7 cases of HeV infection among humans in [...]

A national survey of 1,001 Australians found that most were concerned about a bioterrorist attack and were ill-informed about smallpox prevention and response. Since general practitioners were commonly identified as [...]

Abstract Background The population of Nukufetau, a remote coral atoll island in Tuvalu in the Western Pacific, received annual mass drug administration (MDA) of diethylcarbamazine and albendazole under the Pacific Elimination of Lymphatic Filariasis program in 2001, 2002 and 2003, with the last MDA occurring six months before a cross-sectional survey of the whole population for soil transmitted helminths (STH). Methods A cross-sectional survey in May 2004 recruited 206 residents (35.2% of the population) who provided a single faecal sample that was preserved, concentrated and examined microscopically. Results Overall prevalence of STH was 69.9%; only hookworm and Trichuris trichiura were diagnosed. Trichuris was present in 68.4% with intensity of infection being light in 56.3%, medium in 11.7% and heavy in 0.5%. Hookworm occurred in 11.7% with intensity of infection 11.2% being light and medium in 0.5%. Twenty individuals (9.7%) had dual infections. The prevalence of Trichuris was constant across all ages while the prevalence of hookworm was significantly lower in residents below 30 years of age. In the age group 5–12 years comparison of results with a 2001 survey 1 suggested that the prevalence of STH has declined minimally, due to sustained high prevalence of Trichuris, while hookworm has declined dramatically from 34.4% to 1.6%. Conclusion The results of this survey suggest that although the MDA appears to have reduced hookworm prevalence in residents below 30 years of age, there has been minimal effect on Trichuris prevalence. An integrated program to control STH is required.