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Examination of the vaccine strategies and technical platforms used for the COVID-19 pandemic in the context of those used for previous emerging and reemerging infectious diseases and pandemics may offer some mutually beneficial lessons. The unprecedented scale and rapidity of dissemination of recent emerging infectious diseases pose new challenges for vaccine developers, regulators, health authorities and political constituencies. Vaccine manufacturing and distribution are complex and challenging. While speed is essential, clinical development to emergency use authorization and licensure, pharmacovigilance of vaccine safety and surveillance of virus variants are also critical. Access to vaccines and vaccination needs to be prioritized in low- and middle-income countries. The combination of these factors will weigh heavily on the ultimate success of efforts to bring the current and any future emerging infectious disease pandemics to a close. Examination of the vaccine strategies and technical platforms used for the COVID-19 pandemic in the context of those used for previous emerging and reemerging infectious diseases and pandemics can offer critical lessons to prepare for future public health emergencies., Author(s): Jean-Louis Excler [sup.1] , Melanie Saville [sup.2] , Seth Berkley [sup.3] , Jerome H. Kim [sup.1] Author Affiliations: (1) International Vaccine Institute, Seoul, Republic of Korea (2) Coalition for [...]

Introduction: Thailand plays a substantial role in global HIV-1 transmission of CRF01_AE. Worldwide, men who have sex with men (MSM) are at elevated risk for HIV-1 infection. Hence, understanding HIV-1 diversity in a primarily Thai MSM cohort with acute infection, and its connections to the broader HIV-1 transmission network in Asia is crucial for research and development of HIV-1 vaccines, treatment and cure. Methods: Subtypes and diversity of infecting viruses from individuals sampled from 2009 to 2015 within the RV254/SEARCH 010 cohort were assessed by multiregion hybridization assay (MHAbce), multiregion subtype-specific PCR assay (MSSPbce) and full-length single-genome sequencing (SGS). Phylogenetic analysis was performed by maximum likelihood. Pairwise genetic distances of envelope gp160 sequences obtained from the cohort and from Asia (Los Alamos National Laboratory HIV Database) were calculated to identify potential transmission networks. Results: MHAbce/MSSPbce results identified 81.6% CRF01AE infecting strains in RV254. CRF01AE/B recombinants and sub-type B were found at 7.3% and 2.8% respectively. Western subtype B strains outnumbered Thai B' strains. Phylogenetic analysis revealed one C, one CRF01_AE/CRF02_AG recombinant and one CRF01_AE/B/C recombinant. Asian network analysis identified one hundred and twenty-three clusters, including five clusters of RV254 participants. None of the RV254 sequences clustered with non-RV254 sequences. The largest international cluster involved 15 CRF01AE strains from China and Vietnam. The remaining clusters were mostly intracountry connections, of which 31.7% included Thai nodes and 43.1% included Chinese nodes. Conclusion: While the majority of strains in Thailand are CRF01AE and subtype B, emergence of unique recombinant forms (URFs) are found in a moderate fraction of new HIV-1 infections. Approaches to vaccine design and immunotherapeutics will need to monitor and consider the expanding proportion of recombinants and the increasing genetic diversity in the region. Identified HIV-1 transmission networks indicate ongoing spread of HIV-1 among MSM. As HIV-1 epidemics continue to expand in other Asian countries, transmission network analyses can inform strategies for prevention, intervention, treatment and cure. Keywords: HIV-1 molecular epidemiology; Thailand; Asia transmission network; MSM; acute infection; recombinants; vaccine; intervention, Additional Supporting Information may be found online in the Supporting information tab for this article. 1 INTRODUCTION Over 30 years have passed since the first case of HIV-1 was reported [...]

Improving water and sanitation is the preferred choice for cholera control in the long-term. Nevertheless, vaccination is an available tool that has been shown to be a cost-effective option for cholera prevention in endemic countries or during outbreaks. In 2011 the first low-cost oral cholera vaccine for international use was given prequalification by the World Health Organization (WHO). To increase and prioritize use of the vaccine, WHO created a global stockpile in 2013 from which countries may request oral cholera vaccine for reactive campaigns. WHO has issued specific guidelines for applying for the vaccine, which was previously in short supply (despite prequalification for a second oral vaccine in 2015). The addition of a third WHO-prequalified oral cholera vaccine in 2016 is expected to increase the global stockpile considerably and alleviate supply issues. However, prioritization and best use of the vaccine (e.g. how, when and where to use) will remain challenges. We describe 12 past oral cholera vaccine campaigns, conducted in settings with varying burdens of cholera. These case studies illustrate three key challenges faced in the use of the oral cholera vaccines: regulatory hurdles, cold chain logistics and vaccine coverage and uptake. To pave the way for the introduction of current and future oral cholera vaccines, we discuss operational challenges and make recommendations for future research with respect to each of these challenges. Ameliorer l'acces a l'eau et a l'assainissement est le meilleur moyen de lutter contre le cholera a long terme. Neanmoins, la vaccination s'avere etre un outil accessible et rentable pour la prevention du cholera dans les pays ou cette maladie est endemique ou pendant des epidemies. En 2011, l'Organisation mondiale de la Sante (OMS) a preselectionne le premier vaccin anticholerique oral a faible cout destine a un usage international. Afin de favoriser et de hierarchiser l'usage de ce vaccin, l'OMS a cree en 2013 une reserve mondiale aupres de laquelle les pays peuvent demander des vaccins anticholeriques oraux et mettre en ceuvre des campagnes reactives. L'OMS a publie des directives specifiques pour demander ce vaccin, qui n'etait auparavant disponible qu'en quantite limitee (malgre la preselection d'un second vaccin oral en 2015). L'ajout, en 2016, d'un troisieme vaccin anticholerique oral preselectionne par l'OMS devrait permettre d'augmenter sensiblement les reserves mondiales et d'attenuer les problemes d'approvisionnement. II restera cependant a traiter les questions de la hierarchisation et du meilleur usage du vaccin (par ex., comment, a quel moment et a quel endroit l'utiliser). Nous decrivons ici 12 campagnes de vaccination orale contre le cholera qui ont ete menees dans des regions diversement touchees par cette maladie. Ces etudes de cas illustrent trois grands defis qui se posent lors de l'utilisation de vaccins anticholeriques oraux: les obstacles reglementaires, la logistique de la chaine du froid et la couverture ainsi que le taux de vaccination. Afin de preparer introduction de vaccins anticholeriques oraux, existants et futurs, nous examinons les difficultes operationnelles et formulons des recommandations concernant de futurs travaux de recherche sur chacune de ces difficultes. La mejora del agua y el saneamiento es la option preferida para el control. del colera a largo plazo. Sin embargo, la vacunacion es una herramienta disponible que ha demostrado ser una alternativa rentable para la prevention del colera en paises endemicos o durante brotes. En 2011, la Organization Mundial de la Salud (OMS) precalifico la primera vacuna anticolerica oral de bajo coste para uso internacional. Para aumentary priorizar el uso de la vacuna, en 2013 la OMS creo una reserva global de la cual los paises podian solicitar vacunas anticolericas orales para campanas reactivas. La OMS ha publicado directrices especfficas para la aplicacion de la vacuna, cuyo suministro era escaso anteriormente (a pesar de la precalificacion para una segunda vacuna oral en 2015). Esta previsto que el hecho de anadir una tercera vacuna anticolerica oral precalificada por la OMS en 2016 aumente las reservas globales de forma considerabley reduzca los problemas de suministro. No obstante, la priorizacion y el buen uso de la vacuna (por ejemplo, como, cuando y donde utilizarla) seguiran siendo asuntos importantes. Se describen 12 campanas anteriores de vacunacion oral contra el colera, realizadas en entornos con distintos niveles de colera. Estos estudios de casos ilustran los tres problemas principales que surgen al utilizer vacunas anticolericas orales: obstaculos reglamentarios, logistica de la gestion de la cadena de frio y cobertura y aceptacion de la vacuna. Para allanar el terreno en la introduction de vacunas anticolericas orales en el presente y en el future, se analizan las dificultades operativas y se presentan recomendaciones para futuras investigaciones con respecto a estos problemas., Introduction The World Health Organization (WHO) estimates that there are 1.3 to 4.0 million cholera cases annually and that 21 000 to 143 000 of them result in death. (1) [...]

: Introduction: Thailand plays a substantial role in global HIV‐1 transmission of CRF01_AE. Worldwide, men who have sex with men (MSM) are at elevated risk for HIV‐1 infection. Hence, understanding HIV‐1 diversity in a primarily Thai MSM cohort with acute infection, and its connections to the broader HIV‐1 transmission network in Asia is crucial for research and development of HIV‐1 vaccines, treatment and cure. Methods: Subtypes and diversity of infecting viruses from individuals sampled from 2009 to 2015 within the RV254/SEARCH 010 cohort were assessed by multiregion hybridization assay (MHAbce), multiregion subtype‐specific PCR assay (MSSPbce) and full‐length single‐genome sequencing (SGS). Phylogenetic analysis was performed by maximum likelihood. Pairwise genetic distances of envelope gp160 sequences obtained from the cohort and from Asia (Los Alamos National Laboratory HIV Database) were calculated to identify potential transmission networks. Results: MHAbce/MSSPbce results identified 81.6% CRF01_AE infecting strains in RV254. CRF01_AE/B recombinants and subtype B were found at 7.3% and 2.8% respectively. Western subtype B strains outnumbered Thai B′ strains. Phylogenetic analysis revealed one C, one CRF01_AE/CRF02_AG recombinant and one CRF01_AE/B/C recombinant. Asian network analysis identified one hundred and twenty‐three clusters, including five clusters of RV254 participants. None of the RV254 sequences clustered with non‐RV254 sequences. The largest international cluster involved 15 CRF01_AE strains from China and Vietnam. The remaining clusters were mostly intracountry connections, of which 31.7% included Thai nodes and 43.1% included Chinese nodes. Conclusion: While the majority of strains in Thailand are CRF01_AE and subtype B, emergence of unique recombinant forms (URFs) are found in a moderate fraction of new HIV‐1 infections. Approaches to vaccine design and immunotherapeutics will need to monitor and consider the expanding proportion of recombinants and the increasing genetic diversity in the region. Identified HIV‐1 transmission networks indicate ongoing spread of HIV‐1 among MSM. As HIV‐1 epidemics continue to expand in other Asian countries, transmission network analyses can inform strategies for prevention, intervention, treatment and cure., Introduction Over 30 years have passed since the first case of HIV‐1 was reported in Thailand. In the mid‐1980s, cases of HIV‐1 in the country were largely limited to people [...]

Infectious diseases are responsible for approximately 25% of global mortality, especially in children aged younger than 5 years. Much of the burden of infectious diseases could be alleviated if appropriate mechanisms could be put in place to ensure access for all children to basic vaccines, regardless of geographical location or economic status. In addition, new safe and effective vaccines should be developed for a variety of infections against which no effective preventive intervention measure is either available or practical. The public, private, and philanthropic sectors need to join forces to ensure that these new or improved vaccines are fully developed and become accessible to the populations in need as quickly as possible.

A fundamental goal of current strategies to develop an efficacious vaccine for AIDS is the elicitation of broadly reactive cytotoxic T lymphocyte (CTL) reactivities capable of destroying virally infected targets. Recent application of recombinant canarypox ALVAC/HIV-1 vectors as vaccine immunogens in HIV-1,-noninfected volunteers has produced CTL responses in a significant number of vaccinees. Using a newly developed targeting strategy, we examined the capacity of vaccine-induced CTL to lyse autologous targets infected with a diverse group of viral isolates. CTL derived from recipients of a canarypox ALVAC/HIV-1 gp160 (MN) vaccine were found capable of lysing autologous CD[4.sup.+] lymphoblasts infected with the prototypic LAI strain of HIV-1. When tested against autologous targets infected with primary HIV-1 isolates representing genetically diverse viral clades, CTL from ALVAC/gp160 recipients showed both a broad pattern of cytolysis in which viruses from all clades tested were recognized as well as a highly restricted pattern in which no primary isolates, including clade B, were lysed. Differences in the HLA haplotypes of the volunteers immunized with the envelope vector might be a major determinant of the relative breadth of their CTL response. In contrast to ALVAC/gp160 vaccinees, recipients of the ALVAC/HIV-1 immunogen containing envelope as well as gag and protease genes consistently had CTL reactivities effective against a spectrum of primary isolate-infected targets. These studies demonstrate for the first time that clade B-based canarypox vaccines can elicit broad CTL reactivities capable of recognizing viruses belonging to genetically diverse HIV-1 clades. The results also reinforce the impact of viral core elements in the vaccine as well as the pattern of major histocompatibility complex class I allelic expression by the vaccine recipient in determining the relative breadth of the cellular response.