The following protocol has been designed to investigate the extent of infection, as determined by seropositivity in the general population, in any country in which COVID-19 virus infection has been reported. Each country may need to tailor some aspects of this protocol to align with public health, l...aboratory and clinical systems, according to capacity, availability of resources and cultural appropriateness. However, using a standardized protocol such as this one below, epidemiological exposure data and biological samples can be systematically collected and shared rapidly in a format that can be easily aggregated, tabulated and analyzed across many different settings globally for timely estimates of COVID-19 virus infection severity and attack rates, as well as to inform public health responses and policy decisions. This is particularly important in the context of a novel respiratory pathogen, such as COVID-19 virus
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Nota científica
24 de abril de 2020
El desarrollo de inmunidad a un patógeno por infección natural es un proceso de varias etapas que suele producirse a lo largo de una o dos semanas. El organismo responde a una infección vírica de forma inmediata a través de una respuesta innata no específ...ica, en la que los macrófagos, los neutrófilos y las células dendríticas frenan el avance del virus y pueden incluso evitar que este provoque síntomas. A esta respuesta no específica le sigue una respuesta adaptativa en la que el organismo genera anticuerpos que se unen específicamente al virus. Estos anticuerpos son las proteínas denominadas inmunoglobulinas. El organismo también genera linfocitos T que reconocen y eliminan las células infectadas por el virus: es lo que se conoce como inmunidad celular. Esta respuesta adaptativa combinada puede eliminar el virus del organismo y, si la respuesta es suficientemente intensa, puede evitar el agravamiento de la enfermedad o la reinfección por el mismo virus. Este proceso se mide a menudo a través de la presencia de anticuerpos en la sangre.
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Document d’information scientifique
24 avril 2020
Le développement d’une immunité face à un agent pathogène à la suite d’une infection naturelle comporte plusieurs étapes et prend généralement une à deux semaines. Une infection virale entraîne immédiatement une réponse immunit...aire innée, non spécifique, au cours de laquelle les macrophages, les neutrophiles et les cellules dendritiques ralentissent la progression du virus et peuvent même éviter l’apparition de symptômes. Cette réponse non spécifique est suivie d’une réponse adaptative, au cours de laquelle l’organisme produit des anticorps qui se lient spécifiquement au virus. Ces anticorps sont des protéines appelées immunoglobulines. L’organisme produit également des lymphocytes T qui reconnaissent et éliminent les cellules infectées par le virus. Cette réponse adaptative permet parfois d’éliminer le virus de l’organisme et, si elle est suffisamment forte, d’éviter l’aggravation de la maladie ou la réinfection par le même virus. Ce processus est souvent mesuré par la présence d’anticorps dans le sang.
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Breastfeeding is the cornerstone of infant and young child survival, nutrition and development and maternal health. The World Health Organization recommends exclusive breastfeeding for the first 6 months of life, followed by continued breastfeeding with appropriate complementary foods for up to 2 ye...ars and beyond.1 Early and uninterrupted skin-toskin contact, rooming-in2 and kangaroo mother care3 also significantly improve neonatal survival and reduce morbidity and are recommended by WHO.
Corrigendum 23 June 2020
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The number of confirmed COVID-19 cases detected and reported in each country is influenced by
many factors including limited access and/or utilization of healthcare and COVID-19 testing, limited
surveillance, lack of knowledge amongst the population about when to seek testing, an asymptomatic pres...entation, and other unknown issues. This is true in all countries of the world, and not Africa specific, however there are factors unique to Africa which may also affect the way the virus behaves there. COVID-19 prevalence data are critical for planning effective mitigation strategies and understandingthe true impact of the disease and relevant intervention measures in Africa, which might be quite different from regions with a different population age distribution or risk factor profile.
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Available in Arabic, Chinese, English, French, Portuguese and Spanish
https://apps.who.int/iris/handle/10665/334254
The growing understanding of how sequence information can contribute to improved public health is driving global investments in sequencing facilities and programmes. The falling cost and complexity of generating GSD provides opportunities for expanding sequencing capacity; however, challenges to wid...espread implementation remain. This document provides policy-makers and stakeholders with guidance on how to maximize the public health benefit of SARS-CoV-2 genomic sequencing activities in the short and long term as the pandemic continues to unfold. Practical considerations for the implementation of a virus genomic sequencing programme and an overview of the public health objectives of genomic sequencing are covered. This guidance focuses on SARS-CoV-2 but is applicable to other pathogens of public health concern.
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February 2021.
Improving our response to the ongoing COVID-19 pandemic in Africa requires regularly updated information, constant innovation, and considerable support towards research and development (R&D) for priorities that respond to the African realities. Shaping the research agenda and stimula...ting the generation, translation, and dissemination of valuable knowledge is one of the core functions of the African Academy of Sciences (AAS), African Centre for Disease Control (Africa CDC), and WHO-AFRO. We need answers to a list of critical research questions that respond to the current realities on the African continent to guide the COVID-19 outbreak control efforts
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1 March 2021
This article is part of a series of explainers on vaccine development and distribution. Learn more about vaccines – from how they work and how they’re made to ensuring safety and equitable access – in WHO’s Vaccines Explained series.
An overview of COVID-19 Vaccine AstraZeneca and why it is authorised in the EU. Available in 22 languages
18 Febr. 2021
The guide explains how vaccines work and answers your common questions as well as providing up-to-date information on the current approved COVID-19 vaccinations in the UK.
This guide was written in January 2021 and updated in March 2021 and is accurate at the time of publishing. Information will b...e updated as it becomes available.
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29 Dec 2021. Comprehensive slideset updated regularly to include the latest data and guidance on best practices for COVID-19 diagnosis and prevention of COVID-19 transmission.
26 March 2021 Slideset updated regularly to include the latest data on the evolution and duration of COVID-19 symptoms and prevalence and duration of natural immunity.
Natural immunity against COVID-19
Scientific report 10 May 2021
Hendra virus (HeV) continues to pose a serious public health concern as spillover events occur sporadically. Terminally ill horses can exhibit a range of clinical signs including frothy nasal discharge, ataxia or forebrain signs. Early signs, if detected, can include depression, inappetence, colic o...r mild respiratory signs. All unvaccinated ill horses in areas where flying foxes exist, may potentially be infected with HeV, posing a significant risk to the veterinary community. Equivac® HeV vaccine has been fully registered in Australia since 2015 (and under an Australian Pesticides and Veterinary Medicines Authority special permit since 2012) for immunization of horses against HeV and is the most effective and direct solution to prevent disease transmission to horses and protect humans. No HeV vaccinated horse has tested positive for HeV infection. There is no registered vaccine to prevent, or therapeutics to treat, HeV infection in humans. Previous equine HeV outbreaks tended to cluster in winter overlapping with the foaling season (August to December), when veterinarians and horse owners have frequent close contact with horses and their bodily fluids, increasing the chance of zoonotic disease transmission. The most southerly case was detected in 2019 in the Upper Hunter region in New South Wales, which is Australia's Thoroughbred horse breeding capital. Future spillover events are predicted to move further south and inland in Queensland and New South Wales, aligning with the moving distribution of the main reservoir hosts. Here we (1) review HeV epidemiology and climate change predicted infection dynamics, (2) present a biosecurity protocol for veterinary clinics and hospitals to adopt, and (3) describe diagnostic tests currently available and those under development. Major knowledge and research gaps have been identified, including evaluation of vaccine efficacy in foals to assess current vaccination protocol recommendations.
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