After infection by SARS-CoV-2, both hospitalized and nonhospitalized patients have an increased risk of various persistent physical symptoms that may impair their quality of life, such as fatigue, breathlessness, or impaired attention.^1-3 Although the term “long COVID” has been coined to describe these symptoms⁴ and putative mechanisms have been proposed,^3,5,6 the symptoms may not emanate from SARS-CoV-2 infection per se but instead may be ascribed to SARS-CoV-2 despite having other causes. In this study, we examined the association of self-reported COVID-19 infection and of serology test results with persistent physical symptoms. We hypothesized that the belief in having been infected with SARS-CoV-2 would be associated with persistent symptoms while controlling for actual infection.

Background: We aimed to estimate the seropositivity to anti-SARS-CoV-2 antibodies in May–June 2020 after the first lockdown period in adults living in three regions in France and to identify the associated risk factors. Methods: Between 4 May 2020 and 23 June 2020, 16 000 participants in a survey on COVID-19 from an existing consortium of three general adult population cohorts living in the Ile-de-France (IDF) or Grand Est (GE) (two regions with high rate of COVID-19) or in the Nouvelle-Aquitaine (NA) (with a low rate) were randomly selected to take a dried-blood spot for anti-SARS-CoV-2 antibodies assessment with three different serological methods (ClinicalTrial Identifier #NCT04392388). The primary outcome was a positive anti-SARS-CoV-2 ELISA IgG result against the spike protein of the virus (ELISA-S). Estimates were adjusted using sampling weights and post-stratification methods. Multiple imputation was used to infer the cumulative incidence of SARS-CoV-2 infection with adjustments for imperfect tests accuracies. Results: The analysis included 14 628 participants, 983 with a positive ELISA-S. The weighted estimates of seropositivity and cumulative incidence were 10.0% [95% confidence interval (CI): 9.1%, 10.9%] and 11.4% (95% CI: 10.1%, 12.8%) in IDF, 9.0% (95% CI: 7.7%, 10.2%) and 9.8% (95% CI: 8.1%, 11.8%) in GE and 3.1% (95% CI: 2.4%, 3.7%) and 2.9% (95% CI: 2.1%, 3.8%) in NA, respectively. Seropositivity was higher in younger participants [odds ratio (OR) = 1.84 (95% CI: 1.79, 6.09) in <40 vs 50–60 years old and OR = 0.56 (95% CI: 0.42, 0.74) in ≥70 vs 50–60 years old)] and when at least one child or adolescent lived in the same household [OR = 1.30 (95% CI: 1.11, 1.53)] and was lower in smokers compared with non-smokers [OR = 0.71 (95% CI: 0.57, 0.89)]. Conclusions: Seropositivity to anti-SARS-CoV-2 antibodies in the French adult population was ≤10% after the first wave. Modifiable and non-modifiable risk factors were identified.

Persistent symptoms after SARS-CoV-2 infection are an emerging public health problem. According to the World Health Organization (WHO), the post–COVID-19 condition, commonly referred to as long COVID, is defined as “the illness that occurs in people who have a history of probable or confirmed SARS-CoV-2 infection; usually within 3 months from the onset of COVID-19, with symptoms and effects that last for at least 2 months.”¹ Factors such as age, female sex, comorbid conditions, and number of symptoms during the acute phase of the infection are known to be associated with the occurrence of long COVID.^2-6 Whether some of these persistent symptoms will resolve more than 1 year after the acute infection has not yet been well explored, to our knowledge, especially in the general population.⁷ This work aims to describe the temporal dynamics of symptoms after SARS-CoV-2 infection, to characterize persistent symptoms, and to identify factors associated with their resolution.

Here we propose a strategy allowing implementing efficient and practicable large-scale seroepidemiological studies for Zika Virus (ZIKV). It combines screening by a commercial NS1 protein-based Zika IgG ELISA, and confirmation by a cytopathic effect-based virus neutralization test (CPE-based VNT). In post-epidemic samples from Martinique Island blood donors (a population with a dengue seroprevalence above 90%), this strategy allowed reaching specificity and sensitivity values over 98%. The CPE-based VNT consists of recording CPE directly under the optical microscope, which is easy to identify with ZIKV strain H/PF/2013 at day 5 pi. Overall, considered that CPE-based VNT is cost effective and widely automatable, the NS1 protein-based Zika IgG ELISA+CPE-based VNT combination strategy represents a convenient tool to expedite ZIKV seroprevalence studies.

The ongoing significant social, environmental, and economic changes in Southeast Asia (SEA) make the region highly vulnerable to the emergence and re-emergence of zoonotic viral diseases. In the last century, SEA has faced major viral outbreaks with great health and economic impact, including Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), arboviruses, highly pathogenic avian influenza (H5N1), and Severe Acute Respiratory Syndrome (SARS-CoV); and so far, imported cases of Middle East Respiratory Syndrome Coronavirus (MERS-CoV). Given the recent challenging experiences in addressing emerging zoonotic diseases, it is necessary to redouble efforts to effectively implement the “One Health” initiative in the region, which aims to strengthen the human-animal–plant-environment interface to better prevent, detect and respond to health threats while promoting sustainable development. This review provides an overview of important emerging and re-emerging zoonotic viral diseases in SEA, with emphasis on the main drivers behind their emergency, the epidemiological situation from January 2000 to October 2022, and the importance of One Health to promote improved intervention strategies.

Zika virus (ZIKV), was widely reported in Latin America and has been associated with neuropathologies, as microcephaly, but only few seroprevalence studies have been published to date. Our objective was to determine the seroprevalence amongst Bolivian blood donors and estimate the future potential circulation of the virus. A ZIKV seroprevalence study was conducted between December 2016 and April 2017 in 814 asymptomatic Bolivian volunteer blood donors residing in various eco-environments corresponding to contrasting entomological activities. It was based on detection of IgG to ZIKV using NS1 ELISA screening, followed by a seroneutralisation test in case of positive or equivocal ELISA result. Analysis revealed that ZIKV circulation occurred in tropical areas (Beni: 39%; Santa Cruz de la Sierra: 21.5%) but not in highlands (~0% in Cochabamba, La Paz, Tarija). It was modulated by Aedes aegypti activity and the virus spread was not limited by previous immunity to dengue. Cases were geo-localised in a wide range of urban areas in Santa Cruz and Trinidad. No differences in seroprevalence related to gender or age-groups could be identified. It is concluded that ZIKV has been intensely circulating in the Beni region and has still a significant potential for propagating in the area of Santa Cruz. Zika virus (ZIKV) is a virus of African origin, transmitted by Aedes mosquitoes, and related to dengue and yellow fever virus. It was originally believed to be responsible for a mild febrile illness in Africa and South-east Asia. However, in recent years, ZIKV has been responsible for outbreaks in the Pacific Islands before massively spreading in Latin America and the Caribbean. On this occasion, ZIKV has unexpectedly been associated with non-vector transmission (i.e., sexual and mother-to-foetus transmission) and with severe complications such as foetal abnormalities (e.g. microcephaly) and Guillain-Barré syndromes. Little is known about the actual proportion of the populations infected by ZIKV in Latin America. Here, we report a seroprevalence data in this region, after studying 814 asymptomatic Bolivian volunteer blood donors residing in various eco-environments corresponding to contrasting entomological activities. We conclude that ZIKV has been circulating in Bolivian tropical areas but not in highlands, and that the epidemic has not been limited by previous immunity against dengue. Specific attention should be paid to the region of Santa Cruz, where the seroprevalence is still limited, but the density of Aedes aegypti populations makes plausible further spreading of the disease.