Treatment-shortening regimens for tuberculosis: updates and future priorities

In the past 2 years, remarkable advances have been made in shortening tuberculosis (TB) treatment. In particular, four clinical trials (Study 31/A5349, Nix-TB, ZeNix and TB-PRACTECAL) have provided evidence of the efficacy of regimens based on new and repurposed drugs: the 4-month regimen for drug-susceptible TB, and the 6-month bedaquiline–pretomanid–linezolid regimen with or without moxifloxacin for multidrug-resistant/rifampicin-resistant TB. Even if the evidence at the basis of these new regimens is compelling, several questions remain open, particularly concerning linezolid dose finding, the upsurging threat of bedaquiline-resistant Mycobacterium tuberculosis and the feasibility of applying these results to the paediatric population. Several ongoing trials may fill the remaining gaps and produce further reliable evidence to address the outstanding questions in TB treatment shortening

Sylvatic Dengue Virus Type 2 Activity in Humans, Nigeria, 1966

Using phylogenetic analysis of complete virus genomes from human isolates obtained in Nigeria in 1966, we identified sylvatic dengue virus (DENV) strains from 3 febrile patients. This finding extends current understanding of the role of sylvatic DENV in febrile disease and documents another focus of sylvatic DENV transmission in West Africa

Evaluación in vitro de la resistencia antimicrobiana en Campylobacter termotolerantes presentes en planta de faena aviar

Presentado en: VIII Jornada de difusión de la Investigación y Extensión FCV-UNL 2020Considerando que Campylobacter termotolerante (CT) es un agente zoonótico de gran relevancia en la seguridad alimentaria y, por ende, en la salud pública, se desarrolló este trabajo con el objetivo de determinar fenotípicamente el perfil de resistencia antimicrobiana de aislamientos de CT obtenidos durante el proceso de faena. Se trabajó con una colección de aislamientos de CT (n=102), los cuales fueron obtenidos durante el año 2015 a partir de muestras tomadas en diferentes etapas del proceso de faena de pollos parrilleros. Se evaluó la concentración inhibitoria mínima de los aislamientos frente a fluorquinolonas (ciprofloxacina y enrofloxacina). Desde el punto de vista epidemiológico, el 90% de las cepas de C. jejuni y el 100% de los aislamientos de C. coli presentaron susceptibilidad disminuida frente a CIP. Desde el punto de vista clínico, el 81% de las cepas de C. jejuni y el 100% de las cepas de C. coli fueron resistentes a dicho ATM. Para el caso de ENR, el 76% de las cepas de C. jejuni y el 88% de las cepas de C. coli evidenciaron resistencia. Además, el 2% de las cepas de C. jejuni y el 12% de aquellas correspondientes a C. coli presentaron resistencia intermedia a ENR. La identificación de una elevada proporción de cepas de CT clínicamente resistentes a CIP y ENR compromete la eficacia de la terapia antimicrobiana frente al tratamiento clínico de la campylobacteriosis. Es necesario fortalecer la vigilancia y el control de CT, promoviendo la integración entre las áreas de trabajo de laboratorio, clínica humana y veterinaria.Considering that thermotolerant Campylobacter (TC) is a zoonotic agent of great relevance in food safety and, therefore, in public health, this work was carried out with the objective to determine phenotypically, the antimicrobial resistance profile of TC isolated from different stages of the broiler slaughter process. We worked with a collection of TC isolates (n = 102), which were obtained during 2015 from samples taken at different stages of the slaughter process of broiler chickens. The minimal inhibitory concentration of the isolates was evaluated against fluoroquinolones (ciprofloxacin –CIP- and enrofloxacin –ENR-). From the epidemiological point of view, 90% of the C. jejuni isolates and 100% of the C. coli isolates showed decreased susceptibility to CIP. From a clinical point of view, 81% of the C. jejuni and 100% of the C. coli isolates were resistant to this antimicrobial. In the case of ENR, 76% of the C. jejuni strains and 88% of the C. coli strains showed resistance. In addition, 2% of the C. jejuni and 12% of C. coli isolates showed intermediate resistance to ENR. The identification of a high proportion of TC strains clinically resistant to CIP and ENR threatens the efficacy of antimicrobial therapy against the clinical treatment of campylobacteriosis. It is necessary to strengthen the TC surveillance and control, promoting integration between the laboratory, human clinic and veterinary areas.EEA RafaelaFil: Schreyer, M. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Salud Pública; ArgentinaFil: Schreyer, M. Universidad Nacional del Litoral. Instituto de Ciencias Veterinarias del Litoral. (ICiVet-Litoral). Laboratorio de Análisis de Alimentos; ArgentinaFil: Schreyer, M. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias Veterinarias del Litoral. (ICiVet-Litoral). Laboratorio de Análisis de Alimentos; ArgentinaFil: Olivero, C. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Salud Pública; ArgentinaFil: Olivero, C. Universidad Nacional del Litoral. Instituto de Ciencias Veterinarias del Litoral. (ICiVet-Litoral). Laboratorio de Análisis de Alimentos; ArgentinaFil: Olivero, C. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias Veterinarias del Litoral. (ICiVet-Litoral). Laboratorio de Análisis de Alimentos; ArgentinaFil: Rossler, E. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Salud Pública; ArgentinaFil: Rossler, E. Universidad Nacional del Litoral. Instituto de Ciencias Veterinarias del Litoral. (ICiVet-Litoral). Laboratorio de Análisis de Alimentos; ArgentinaFil: Rossler, E. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias Veterinarias del Litoral. (ICiVet-Litoral). Laboratorio de Análisis de Alimentos; ArgentinaFil: Saluzzo, M. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Salud Pública; ArgentinaFil: Saluzzo, M. Universidad Nacional del Litoral. Instituto de Ciencias Veterinarias del Litoral. (ICiVet-Litoral). Laboratorio de Análisis de Alimentos; ArgentinaFil: Saluzzo, M. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias Veterinarias del Litoral. (ICiVet-Litoral). Laboratorio de Análisis de Alimentos; ArgentinaFil: Frizzo, L.S. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Departamento de Salud Pública; ArgentinaFil: Frizzo, L.S. Universidad Nacional del Litoral. Instituto de Ciencias Veterinarias del Litoral. (ICiVet-Litoral). Laboratorio de Análisis de Alimentos; ArgentinaFil: Frizzo, L.S. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias Veterinarias del Litoral. (ICiVet-Litoral). Laboratorio de Análisis de Alimentos; ArgentinaFil: Signorini, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Signorini, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigación de la Cadena Láctea (IdICaL); ArgentinaFil: Signorini, Marcelo. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación de la Cadena Láctea (IdICaL); ArgentinaFil: Zbrun, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigación de la Cadena Láctea (IdICaL); ArgentinaFil: Zbrun, Maria Virginia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación de la Cadena Láctea (IdICaL); Argentin

First Report of Sylvatic DENV-2-Associated Dengue Hemorrhagic Fever in West Africa

Dengue virus (DENV) circulates in human and sylvatic cycles. Sylvatic strains are both ecologically and evolutionarily distinct from endemic viruses. Although sylvatic dengue cycles occur in West African countries and Malaysia, only a few cases of mild human disease caused by sylvatic strains and one single case of dengue hemorrhagic fever in Malaysia have been reported. Here we report a case of dengue hemorrhagic fever (DHF) with thrombocytopenia (13000/µl), a raised hematocrit (32% above baseline) and mucosal bleeding in a 27-year-old male returning to Spain in November 2009 after visiting his home country Guinea Bissau. Sylvatic DENV-2 West African lineage was isolated from blood and sera. This is the first case of DHF associated with sylvatic DENV-2 in Africa and the second case worldwide of DHF caused by a sylvatic strain

First serological evidence of West Nile virus in human rural populations of Gabon

To investigate West Nile virus (WNV) circulation in rural populations in Gabon, we undertook a large serological survey focusing on human rural populations, using two different ELISA assays. A sample was considered positive when it reacted in both tests. A total of 2320 villagers from 115 villages were interviewed and sampled. Surprisingly, the WNV-specific IgG prevalence was high overall (27.2%) and varied according to the ecosystem: 23.7% in forested regions, 21.8% in savanna, and 64.9% in the lakes region. The WNV-specific IgG prevalence rate was 30% in males and 24.6% in females, and increased with age. Although serological cross-reactions between flaviviruses are likely and may be frequent, these findings strongly suggest that WNV is widespread in Gabon. The difference in WNV prevalence among ecosystems suggests preferential circulation in the lakes region. The linear increase with age suggests continuous exposure of Gabonese populations to WNV. Further investigations are needed to determine the WNV cycle and transmission patterns in Gabon

Randomized controlled field trial to assess the immunogenicity and safety of rift valley fever clone 13 vaccine in livestock

BACKGROUND:Although livestock vaccination is effective in preventing Rift Valley fever (RVF) epidemics, there are concerns about safety and effectiveness of the only commercially available RVF Smithburn vaccine. We conducted a randomized controlled field trial to evaluate the immunogenicity and safety of the new RVF Clone 13 vaccine, recently registered in South Africa. METHODS:In a blinded randomized controlled field trial, 404 animals (85 cattle, 168 sheep, and 151 goats) in three farms in Kenya were divided into three groups. Group A included males and non-pregnant females that were randomized and assigned to two groups; one vaccinated with RVF Clone 13 and the other given placebo. Groups B included animals in 1st half of pregnancy, and group C animals in 2nd half of pregnancy, which were also randomized and either vaccinated and given placebo. Animals were monitored for one year and virus antibodies titers assessed on days 14, 28, 56, 183 and 365. RESULTS:In vaccinated goats (N = 72), 72% developed anti-RVF virus IgM antibodies and 97% neutralizing IgG antibodies. In vaccinated sheep (N = 77), 84% developed IgM and 91% neutralizing IgG antibodies. Vaccinated cattle (N = 42) did not develop IgM antibodies but 67% developed neutralizing IgG antibodies. At day 14 post-vaccination, the odds of being seropositive for IgG in the vaccine group was 3.6 (95% CI, 1.5 - 9.2) in cattle, 90.0 (95% CI, 25.1 - 579.2) in goats, and 40.0 (95% CI, 16.5 - 110.5) in sheep. Abortion was observed in one vaccinated goat but histopathologic analysis did not indicate RVF virus infection. There was no evidence of teratogenicity in vaccinated or placebo animals. CONCLUSIONS:The results suggest RVF Clone 13 vaccine is safe to use and has high (>90%) immunogenicity in sheep and goats but moderate (> 65%) immunogenicity in cattle

Genetic Characterization of Zika Virus Strains: Geographic Expansion of the Asian Lineage

Zika virus (ZIKV) is a mosquito-transmitted flavivirus found in both Africa and Asia. Human infection with the virus may result in a febrile illness similar to dengue fever and many other tropical infections found in these regions. Previously, little was known about the genetic relationships between ZIKV strains collected in Africa and those collected in Asia. In addition, the geographic origins of the strains responsible for the recent outbreak of human disease on Yap Island, Federated States of Micronesia, and a human case of ZIKV infection in Cambodia were unknown. Our results indicate that there are two geographically distinct lineages of ZIKV (African and Asian). The virus has circulated in Southeast Asia for at least the past 50 years, whereupon it was introduced to Yap Island resulting in an epidemic of human disease in 2007, and in 2010 was the cause of a pediatric case of ZIKV infection in Cambodia. This study also highlights the danger of ZIKV introduction into new areas and the potential for future epidemics of human disease

Emerging viral threats in Gabon: health capacities and response to the risk of emerging zoonotic diseases in Central Africa

Emerging infectious diseases (EID) are currently the major threat to public health worldwide and most EID events have involved zoonotic infectious agents. Central Africa in general and Gabon in particular are privileged areas for the emergence of zoonotic EIDs. Indeed, human incursions in Gabonese forests for exploitation purposes lead to intensified contacts between humans and wildlife thus generating an increased risk of emergence of zoonotic diseases. In Gabon, 51 endemic or potential endemic viral infectious diseases have been reported. Among them, 22 are of zoonotic origin and involve 12 families of viruses. The most notorious are dengue, yellow fever, ebola, marburg, Rift Valley fever and chikungunya viruses. Potential EID due to wildlife in Gabon are thereby plentiful and need to be inventoried. The Gabonese Public Health system covers geographically most of the country allowing a good access to sanitary information and efficient monitoring of emerging diseases. However, access to treatment and prevention is better in urban areas where medical structures are more developed and financial means are concentrated even though the population is equally distributed between urban and rural areas. In spite of this, Gabon could be a good field for investigating the emergence or re-emergence of zoonotic EID. Indeed Gabonese health research structures such as CIRMF, advantageously located, offer high quality researchers and facilities that study pathogens and wildlife ecology, aiming toward a better understanding of the contact and transmission mechanisms of new pathogens from wildlife to human, the emergence of zoonotic EID and the breaking of species barriers by pathogens