RESUMEN
Background: The implementation genomic-based surveillance on emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants in low-income countries, which have inadequate molecular and sequencing capabilities and limited vaccine storage, represents a challenge for public health. To date, there is little evidence on molecular investigations of SARS-CoV-2 variants in areas where they might emerge. We report the findings of an experimental SARS-CoV-2 molecular surveillance programme for migrants, refugees, and asylum seekers arriving to Europe via Italy through the Mediterranean Sea. Methods: We descriptively analysed data on migrants collected at entry points in Sicily from February 2021 to May 2022. These entry points are integrated with a network of laboratories fully equipped for molecular analyses, which performed next-generation sequencing and used Nextclade and the Pangolin coronavirus disease 2019 (COVID-19) tools for clade/lineage assignment. Results: We obtained 472 full-length SARS-CoV-2 sequences and identified 12 unique clades belonging to 31 different lineages. The delta variant accounted for 43.6% of all genomes, followed by clades 21D (Eta) and 20A (25.4% and 11.4%, respectively). Notably, some of the identified lineages (A.23.1, A.27, and A.29) predicted their introduction into the migration area. The mutation analysis allowed us to identify 617 different amino acid substitutions, 156 amino acid deletions, 7 stop codons, and 6 amino acid insertions. Lastly, we highlighted the geographical distribution patterns of some mutational profiles occurring in the migrants' countries of origin. Conclusions: Genome-based molecular surveillance dedicated to migrant populations from low-resource areas may be useful for forecasting new epidemiological scenarios related to SARS-CoV-2 variants or other emerging pathogens, as well as for informing the updating of vaccination strategies.
Asunto(s)
COVID-19 , SARS-CoV-2 , Migrantes , Humanos , COVID-19/epidemiología , COVID-19/virología , SARS-CoV-2/genética , Migrantes/estadística & datos numéricos , Europa (Continente)/epidemiología , Genoma Viral , Refugiados/estadística & datos numéricos , Mar Mediterráneo/epidemiología , Italia/epidemiología , MasculinoRESUMEN
Dengue (DENV) and Zika (ZIKV) viruses are mosquito-borne human pathogens. In Italy, the presence of the competent vector Aedes albopictus increases the risk of autochthonous transmission, and a national plan for arboviruses prevention, surveillance, and response (PNA 2020-2025) is in place. The results of laboratory diagnosis of both viruses by the National Reference Laboratory for arboviruses (NRLA) from November 2015 to November 2022 are presented. Samples from 655 suspected cases were tested by both molecular and serological assays. Virus and antibody kinetics, cross-reactivity, and diagnostic performance of IgM ELISA systems were analysed. Of 524 cases tested for DENV, 146 were classified as confirmed, 7 as probable, while 371 were excluded. Of 619 cases tested for ZIKV, 44 were classified as confirmed, while 492 were excluded. All cases were imported. Overall, 75.3% (110/146) of DENV and 50% (22/44) of ZIKV cases were confirmed through direct virus detection methods. High percentages of cross reactivity were observed between the two viruses. The median lag time from symptoms onset to sample collection was 7 days for both DENV molecular (range 0-20) and NS1 ELISA (range 0-48) tests, with high percentages of positivity also after 7 days (39% and 67%, respectively). For ZIKV, the median lag time was 5 days (range 0-22), with 16% positivity after 7 days. Diagnostic performance was assessed with negative predictive values ranging from 92% to 95% for the anti-DENV systems, and of 97% for the ZIKV one. Lower positive predictive values were seen in the tested population (DENV: 55% to 91%, ZIKV: 50%). DENV and ZIKV diagnosis by molecular test is the gold standard, but sample collection time is a limitation. Serological tests, including Plaque Reduction Neutralization Test, are thus necessary. Co-circulation and cross-reactivity between the two viruses increase diagnostic difficulty. Continuous evaluation of diagnostic strategies is essential to improve laboratory testing.
Asunto(s)
Aedes , Dengue , Infección por el Virus Zika , Virus Zika , Humanos , Animales , Infección por el Virus Zika/diagnóstico , Mosquitos Vectores , Italia/epidemiología , Dengue/diagnóstico , Dengue/epidemiologíaRESUMEN
Difficulty in controlling SARS-CoV-2 transmission made the ability to inactivate viruses in aerosols and fomites to be an important and attractive risk reduction measure. Evidence that light frequencies have the ability to inhibit microorganisms has already been reported by many studies which, however, focused on ultraviolet (UV) wavelengths, which are known to induce potential injury in humans. In the present study, the effect on suspensions of SARS-CoV-2 of a Light Emitting Diode (LED) device capable of radiating frequencies in the non-hazardous visible light spectrum (VIS) was investigated. In order to evaluate the efficiency of viral inactivation, plaque assay and western blot of viral proteins were performed. The observed results showed a significant reduction in infectious particles that had been exposed to the LED irradiation of visible light. Furthermore, the analysis of the intracellular expression of viral proteins confirmed the inactivating effect of this irradiation technology. This in vitro study revealed for the first time the inactivation of SARS-CoV-2 through LED irradiation with multiple wavelengths of the visible spectrum. However additional and more in-depth studies can aim to demonstrate the data obtained during these experiments in different matrices, in mutable environmental conditions and on other respiratory viruses such as the influenza virus. The type of LED technology can decisively contribute on reducing virus transmission through the continuous sanitation of common environments without risks for humans and animals.
RESUMEN
This study aimed at the identification of the settings linked to SARS-CoV-2 transmission through the analysis of clusters and small outbreaks detected by the Lombardy Region surveillance system during the second epidemic wave. Comparing the data before and after the introduction of restrictive measures (night curfew, partial closure of schools and businesses, smaart working), we observed a significant decrease of infections in workplaces, social gatherings, coffee shops, restaurants, and sports centers; contagion in schools decreased from 9.2% to 3.4%, in hospitals environments and nursing homes from 5% to 2%; domestic infections increased instead from 73.5% to 92.7%. These results suggest that containment measures have been effective in controlling virus circulation in the community but not at the household level and might inform future interventions, including the establishment of structures (Covid Hotels) for the isolation infected people. At the same time, they raise awareness on the risk of transmission among family members and during households social gatherings.
Asunto(s)
COVID-19/prevención & control , COVID-19/transmisión , Control de Enfermedades Transmisibles/organización & administración , COVID-19/epidemiología , Humanos , ItaliaRESUMEN
INTRODUCTION: Uptake of HIV tests is a challenging issue in vulnerable populations including immigrants, normally using standard diagnostic tools. Objectives of this study were to evaluate the acceptability of HIV rapid test; estimate the percentage of newly HIV diagnoses and evaluate knowledge, attitudes and perception (KAP) about HIV/AIDS and other STIs in a specific set of immigrants and vulnerable population in Rome (Italy). METHODS: All immigrant and Italian people, aged 16-70 years, attending the infectious disease outpatient clinic of the National Institute for Health, Migration and Poverty (INMP) in Rome (Italy), during the period December 2012 to December 2013 were enrolled. HIV rapid testing was provided for free and patients were asked to fill in a questionnaire evaluating KAP about HIV/STIs. All patients with risky sexual behaviours or with a recent diagnosis of STIs were invited to come back after 3-6 months and a post-counselling questionnaire was offered. RESULTS: Out of the total sample, 99.2% (n = 825) accepted the "rapid test" and 10 new HIV diagnoses were found (1.22%; 95% CI 0.58%-2.22%). Three hundred and eighty-five participants (47%) answered the entry questionnaire and 58 (15%) completed the follow-up. Overall, we found high knowledge about HIV/AIDS; however, lower educational level and immigrant status were associated with poor knowledge about HIV, other STIs and prevention methods. Immigrants have lower perception of sexual risk and higher prejudice than Italians. CONCLUSIONS: Our study showed high acceptance of rapid test in this specific vulnerable population and this allowed to identify new HIV diagnoses in unaware people. Socioeconomic inequalities observed in the KAP questionnaire suggest the need for actions to support the reduction of cultural differences in knowledge of HIV/AIDS and for policies aimed at improving access to health services and preventions programmes of marginalized populations.