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Objective To investigate the reliability of the public health event notification assessment process under the International Health Regulations (2005) (IHR). Methods In 2009, 193 National IHR Focal Points (NFPs) were invited to use the decision instrument in Annex 2 of the IHR to determine whether 10 fictitious public health events should be notified to WHO. Each event's notifiability was assessed independently by an expert panel. The degree of consensus among NFPs and of concordance between NFPs and the expert panel was considered high when more than 70% agreed on a response. Findings Overall, 74% of NFPs responded. The median degree of consensus among NFPs on notification decisions was 78%. It was high for the six events considered notifiable by the majority (median: 80%; range: 76-91) but low for the remaining four (median: 55%; range: 54-60). The degree of concordance between NFPs and the expert panel was high for the five events deemed notifiable by the panel (median: 82%; range: 76-91) but low (median: 51%; range: 42-60) for those not considered notifiable. The NFPs identified notifiable events with greater sensitivity than specificity (P< 0.001). Conclusion When used by NFPs, the notification assessment process in Annex 2 of the IHR was sensitive in identifying public health events that were considered notifiable by an expert panel, but only moderately specific. The reliability of the assessments could be increased by expanding guidance on the use of the decision instrument and by including more specific criteria for assessing events and clearer definitions of terms. Objectif Examiner la fiabilite du processus d'evaluation de la notification d'un evenement de sante publique dans le cadre du Reglement sanitaire international (RSI) de 2005. Methodes En 2009, 193 points focaux nationaux RSI (PFN) ont ete invites a utiliser l'instrument de decision figurant a l'annexe 2 du RSI afin de determiner s'il convenait de notifier 10 evenements fictifs de sante publique a l'OMS. l'obligation de notification de chaque evenement a ete evaluee de maniere independante par un groupe d'experts. Le degre de consensus entre les PFN et de concordance entre les PFN et le groupe d'experts etait considere comme etant eleve lorsque plus de 70% s'accordaient sur une reponse. Resultats En tout, 74% des PFN ont repondu. Le degre moyen de consensus parmi les PFN sur les decisions de notification etait de 78%. II etait eleve pour les six evenements consideres comme etant notifiables par la majorite (moyenne: 80%; eventaih 76-91), mais comme etant faible pour les quatre restants (moyenne: 55%; eventaih 54-60). Le degre de concordance entre les PFN et le groupe d'experts etait eleve pour les cinq evenements juges comme etant notifiables par le groupe (moyenne: 82%; eventail: 76-91), mais comme etant faible (moyenne: 51%; eventail: 42-60) pour ceux qui n'etaient pas consideres comme etant notifiables. Les PFN ont identifie les evenements devant etre notifies avec plus de sensibilite que de specificite (P< 0,001). Conclusion Lorsqu'il etait utilise par les PFN, le processus d'evaluation de la notification figurant a l'annexe 2 du RSI etait sensible a l'identification d'evenements de sante publique consideres comine devant etre notifies par un groupe d'experts, mais li n'etait que moderement specifique. La fiabilite des evaluations pourrait etre accrue par une generalisation des recommandations sur l'utilisation de l'instrument de decision et par l'ajout de criteres plus specifiques en matiere d'evaluation des evenements et des definitions terminologiques plus claires. Objetivo Investigar la fiabilidad dei proceso de evaluacion de las notificaciones de episodios incluido en el Reglamento Sanitario Internacional (RSI) de 2005. Metodos En 2009, se propuso a 193 Centros Nacionales de Enlace (CNE) la utilizacion del instrumento de decision induido en el Anexo 2 del RSI para determinar cuales de los 10 acontecimientos ficticios de salud publica debian notificarse a la OMS. Un grupo de expertos evaluo la perceptibilidad de cada suceso de manera independiente. El grado de consenso entre los CNE y de concordancia entre los CNE y el grupo de expertos se considero alto cuando coincidian mas del 70% en una respuesta. Resultados En total respondio el 74% de los CNE. El grado medio de consenso entre los CNE sobre las decisiones de notificacion fue de un 78%. Resulto alto para los seis acontecimientos considerados como notificables por la mayoria (media: 80%; intervalo: 76-91) pero bajo para los cuatro restantes (media: 55%; intervalo: 54-60). El grado de concordancia entre los CNE y el grupo de expertos fue elevado para los cinco sucesos que el grupo de expertos considero como notificables (media: 82%; intervalo: 76-91) pero bajo para aquellos casos que no consideraron notificables (media: 51%; intervalo: 42-60). Los CNE identificaron los sucesos notificables con una mayor sensibilidad que especificidad (p< 0,001). Conclusion Cuando los CNE utilizaron el proceso de evaluacion de notificaciones incluido en el Anexo 2 del RSI, este resulto ser sensible para identificar los acontecimientos de salud publica que un grupo de expertos considero notificable, aunque con una especificidad moderada. La fiabilidad de las evaluaciones podria aumentar si se ampliara la orientacion sobre el uso del instrumento de decision y si se incluyeran criterios mas especificos para evaluar los sucesos y las definiciones de los terminos fueran mas claras., Introduction The International Health Regulations (2005) (IHR), which entered into force in June 2007, are a legally binding agreement between 194 States Parties, including states that are not Member States [...]

Abstract Introduction Timely diagnosis of primary HIV infection is important to prevent further transmission of HIV. Primary HIV infection may take place without symptoms or may be associated with fever, pharyngitis or headache. Sometimes, the clinical presentation includes aseptic meningitis or cutaneous lesions. Intestinal ulceration due to opportunistic pathogens (cytomegalovirus, Epstein-Barr virus, Toxoplasma gondii) has been described in patients with AIDS. However, although invasion of intestinal lymphoid tissue is a prominent feature of human and simian lentivirus infections, colonic ulceration has not been reported in acute HIV infection. Case description A 42-year-old Caucasian man was treated with amoxicillin-clavulanate for pharyngitis. He did not improve, and a rash developed. History taking revealed a negative HIV antibody test five months previously and unprotected sex with a male partner the month before admission. Repeated tests revealed primary HIV infection with an exceptionally high HIV-1 RNA plasma concentration (3.6 × 107 copies/mL) and a low CD4 count (101 cells/mm3, seven percent of total lymphocytes). While being investigated, the patient had a life-threatening hematochezia. After angiographic occlusion of a branch of the ileocaecal artery and initiation of antiretroviral therapy, the patient became rapidly asymptomatic and could be discharged. Colonoscopy revealed a bleeding colonic ulcer. We were unable to identify an etiology other than HIV for this ulcer. Conclusion This case adds to the known protean manifestation of primary HIV infection. The lack of an alternative etiology, despite extensive investigations, suggests that this ulcer was directly caused by primary HIV infection. This conclusion is supported by the well-described extensive loss of intestinal mucosal CD4+ T cells associated with primary HIV infection, the extremely high HIV viral load observed in our patient, and the rapid improvement of the ulcer after initiation of highly active antiretroviral therapy. This case also adds to the debate on treatment for primary HIV infection, especially in the context of severe symptoms and an extremely high viral load.

This paper compares the information rate achieved by SC-FDMA (single-carrier frequency-division multiple access) and OFDMA (orthogonal frequency-division multiple access), where a linear frequency-domain equalizer is assumed to combat frequency selective channels in both systems. Both the single user case and the multiple user case are considered. We prove analytically that there exists a rate loss in SC-FDMA compared to OFDMA if decoding is performed independently among the received data blocks for frequency selective channels. We also provide a geometrical interpretation of the achievable information rate in SC-FDMA systems and point out explicitly the relation to the well-known waterfilling procedure in OFDMA systems. The geometrical interpretation gives an insight into the cause of the rate loss and its impact on the achievable rate performance. Furthermore, motivated by this interpretation we point out and show that such a loss can be mitigated by exploiting multiuser diversity and spatial diversity in multi-user systems with multiple receive antennas. In particular, the performance is evaluated in 3GPP-LTE uplink scenarios.