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1.
Pathog Immun ; 8(2): 74-87, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38347963

RESUMO

Background: Lymphopenia is common in COVID-19. This has raised concerns that COVID-19 could affect the immune system akin to measles infection, which causes immune amnesia and a reduction in protective antibodies. Methods: We recruited COVID-19 patients (n = 59) in Helsinki, Finland, and collected plasma samples on 2 to 3 occasions during and after infection. We measured IgG antibodies to diphtheria toxin, tetanus toxoid, and pertussis toxin, along with total IgG, SARS-CoV-2 spike protein IgG, and neutralizing antibodies. We also surveyed the participants for up to 17 months for long-term impaired olfaction as a proxy for prolonged post-acute COVID-19 symptoms. Results: No significant differences were found in the unrelated vaccine responses while the serological response against COVID-19 was appropriate. During the acute phase of the disease, the SARSCoV-2 IgG levels were lower in outpatients when compared to inpatients. SARS-CoV-2 serology kinetics matched expectations. In the acute phase, anti-tetanus and anti-diphtheria IgG levels were lower in patients with prolonged impaired olfaction during follow up than in those without. Conclusions: We could not detect significant decline in overall humoral immunity during or after COVID-19 infection. In severe COVID-19, there appears to be a temporary decline in total IgG levels.

2.
Indoor Air ; 32(10): e13118, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36305066

RESUMO

SARS-CoV-2 has been detected both in air and on surfaces, but questions remain about the patient-specific and environmental factors affecting virus transmission. Additionally, more detailed information on viral sampling of the air is needed. This prospective cohort study (N = 56) presents results from 258 air and 252 surface samples from the surroundings of 23 hospitalized and eight home-treated COVID-19 index patients between July 2020 and March 2021 and compares the results between the measured environments and patient factors. Additionally, epidemiological and experimental investigations were performed. The proportions of qRT-PCR-positive air (10.7% hospital/17.6% homes) and surface samples (8.8%/12.9%) showed statistical similarity in hospital and homes. Significant SARS-CoV-2 air contamination was observed in a large (655.25 m3 ) mechanically ventilated (1.67 air changes per hour, 32.4-421 L/s/patient) patient hall even with only two patients present. All positive air samples were obtained in the absence of aerosol-generating procedures. In four cases, positive environmental samples were detected after the patients had developed a neutralizing IgG response. SARS-CoV-2 RNA was detected in the following particle sizes: 0.65-4.7 µm, 7.0-12.0 µm, >10 µm, and <100 µm. Appropriate infection control against airborne and surface transmission routes is needed in both environments, even after antibody production has begun.


Assuntos
Poluição do Ar em Ambientes Fechados , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/epidemiologia , RNA Viral , Estudos Prospectivos , Aerossóis e Gotículas Respiratórios
3.
Nanomaterials (Basel) ; 12(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35407155

RESUMO

With the continued scenario of the COVID-19 pandemic, the world is still seeking out-of-the-box solutions to break its transmission cycle and contain the pandemic. There are different transmission routes for viruses, including indirect transmission via surfaces. To this end, we used two relevant viruses in our study. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing the pandemic and human norovirus (HuNV), both known to be transmitted via surfaces. Several nanoformulations have shown attempts to inhibit SARS-CoV-2 and other viruses. However, a rigorous, similar inactivation scheme to inactivate the cords of two tedious viruses (SARS-CoV-2 Alpha variant and HuNV) is lacking. The present study demonstrates the inactivation of the SARS-CoV-2 Alpha variant and the decrease in the murine norovirus (MNV, a surrogate to HuNV) load after only one minute of contact to surfaces including copper-silver (Cu-Ag) nanocomposites. We thoroughly examined the physicochemical characteristics of such plated surfaces using diverse microscopy tools and found that Cu was the dominanting element in the tested three different surfaces (~56, ~59, and ~48 wt%, respectively), hence likely playing the major role of Alpha and MNV inactivation followed by the Ag content (~28, ~13, and ~11 wt%, respectively). These findings suggest that the administration of such surfaces within highly congested places (e.g., schools, public transportations, public toilets, and hospital and live-stock reservoirs) could break the SARS-CoV-2 and HuNV transmission. We suggest such an administration after an in-depth examination of the in vitro (especially on skin cells) and in vivo toxicity of the nanocomposite formulations and surfaces while also standardizing the physicochemical parameters, testing protocols, and animal models.

4.
Nanomaterials (Basel) ; 11(7)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34361206

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains a severe health threat. The COVID-19 infections occurring in humans and animals render human-animal interfaces hot spots for spreading the pandemic. Lessons from the past point towards the antiviral properties of copper formulations; however, data showing the "contact-time limit" surface inhibitory efficacy of copper formulations to contain SARS-CoV-2 are limited. Here, we show the rapid inhibition of SARS-CoV-2 after only 1 and 5 min on two different surfaces containing copper-silver (Cu-Ag) nanohybrids. We characterized the nanohybrids' powder and surfaces using a series of sophisticated microscopy tools, including transmission and scanning electron microscopes (TEM and SEM) and energy-dispersive X-ray spectroscopy (EDX). We used culturing methods to demonstrate that Cu-Ag nanohybrids with high amounts of Cu (~65 and 78 wt%) and lower amounts of Ag (~7 and 9 wt%) inhibited SARS-CoV-2 efficiently. Collectively, the present work reveals the rapid SARS-CoV-2 surface inhibition and the promising application of such surfaces to break the SARS-CoV-2 transmission chain. For example, such applications could be invaluable within a hospital or live-stock settings, or any public place with surfaces that people frequently touch (i.e., public transportation, shopping malls, elevators, and door handles) after the precise control of different parameters and toxicity evaluations.

5.
Adv Virol ; 2021: 6623409, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33927762

RESUMO

In order to plan and execute proper preventative measures against COVID-19, we need to understand how SARS-CoV-2 is transmitted. It has been shown to remain infectious on surfaces from hours to days depending on surface type and environmental factors. The possibility of transmission through fur animals and contaminated pelts, along with the safety of those working with them, is a major concern. SARS-CoV-2 can infect minks and raccoon dogs and has spread to mink farms in numerous countries. Here, we studied the stability of SARS-CoV-2 on blue fox, Finn raccoon, and American mink pelt, fake fur, cotton, plastic, faux leather, and polyester and tested its inactivation by UV light and heat treatment. We detected infectious virus up to 5 days on plastic, up to 1 day on fake fur, less than a day on cotton, polyester, and faux leather, and even 10 days on mink fur. UV light failed to inactivate SARS-CoV-2 on pelts, most likely due to the mechanical protection by the fur. Hence, it should not be used to inactivate the virus on fur products, and its use for other surfaces should also be considered carefully. Heat treatment at 60°C for 1 h inactivated the virus on all surfaces and is a promising method to be applied in practice. This study helps prevent further spread of COVID-19 by increasing our understanding about risks of SARS-CoV-2 spread through contaminated clothing materials and giving important information needed to improve safety of those working in the production line as well as people using the products.

6.
Emerg Infect Dis ; 26(12): 3007-3010, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33219788

RESUMO

Previously identified only in Sierra Leone, Guinea, and southeastern Kenya, Bombali virus-infected Mops condylurus bats were recently found ¼750 km away in western Kenya. This finding supports the role of M. condylurus bats as hosts and the potential for Bombali virus circulation across the bats' range in sub-Saharan Africa.


Assuntos
Quirópteros , Ebolavirus , Doença pelo Vírus Ebola , Animais , Guiné , Quênia/epidemiologia , Serra Leoa
7.
Saf Sci ; 130: 104866, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32834511

RESUMO

We provide research findings on the physics of aerosol and droplet dispersion relevant to the hypothesized aerosol transmission of SARS-CoV-2 during the current pandemic. We utilize physics-based modeling at different levels of complexity, along with previous literature on coronaviruses, to investigate the possibility of airborne transmission. The previous literature, our 0D-3D simulations by various physics-based models, and theoretical calculations, indicate that the typical size range of speech and cough originated droplets ( d ⩽ 20 µ m ) allows lingering in the air for O ( 1 h ) so that they could be inhaled. Consistent with the previous literature, numerical evidence on the rapid drying process of even large droplets, up to sizes O ( 100 µ m ) , into droplet nuclei/aerosols is provided. Based on the literature and the public media sources, we provide evidence that the individuals, who have been tested positive on COVID-19, could have been exposed to aerosols/droplet nuclei by inhaling them in significant numbers e.g. O ( 100 ) . By 3D scale-resolving computational fluid dynamics (CFD) simulations, we give various examples on the transport and dilution of aerosols ( d ⩽ 20 µ m ) over distances O ( 10 m ) in generic environments. We study susceptible and infected individuals in generic public places by Monte-Carlo modelling. The developed model takes into account the locally varying aerosol concentration levels which the susceptible accumulate via inhalation. The introduced concept, 'exposure time' to virus containing aerosols is proposed to complement the traditional 'safety distance' thinking. We show that the exposure time to inhale O ( 100 ) aerosols could range from O ( 1 s ) to O ( 1 min ) or even to O ( 1 h ) depending on the situation. The Monte-Carlo simulations, along with the theory, provide clear quantitative insight to the exposure time in different public indoor environments.

8.
Vector Borne Zoonotic Dis ; 20(2): 155-158, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31503522

RESUMO

Coronaviruses (CoVs) represent a global public health threat, exemplified by the severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) outbreaks. Using fecal samples collected from five bat species between 2014 and 2016 in Finland and RT-PCR, RT-qPCR, and NGS, we identified CoVs in 10 of 79 (13%) samples, including two novel bat species-CoV relationships. Phylogenetic analysis revealed Alphacoronavirus and Betacoronavirus species clustered among previously identified bat and human viruses. These results expand the known northern distribution and host species range of bat-borne CoVs.


Assuntos
Quirópteros/virologia , Infecções por Coronavirus/veterinária , Coronavirus/isolamento & purificação , Animais , Coronavirus/classificação , Coronavirus/genética , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Estudos Transversais , Fezes/virologia , Finlândia/epidemiologia , Filogenia , Especificidade da Espécie
9.
Emerg Infect Dis ; 25(5): 955-957, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31002301

RESUMO

Bombali virus (genus Ebolavirus) was identified in organs and excreta of an Angolan free-tailed bat (Mops condylurus) in Kenya. Complete genome analysis revealed 98% nucleotide sequence similarity to the prototype virus from Sierra Leone. No Ebola virus-specific RNA or antibodies were detected from febrile humans in the area who reported contact with bats.


Assuntos
Quirópteros/virologia , Ebolavirus , Animais , Ebolavirus/classificação , Ebolavirus/genética , Genoma Viral , Geografia , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/transmissão , Doença pelo Vírus Ebola/virologia , Quênia/epidemiologia , Filogenia , Vigilância em Saúde Pública
10.
Emerg Infect Dis ; 22(5): 810-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27088268

RESUMO

Inkoo virus (INKV) and Chatanga virus (CHATV), which are circulating in Finland, are mosquitoborne California serogroup orthobunyaviruses that have a high seroprevalence among humans. Worldwide, INKV infection has been poorly described, and CHATV infection has been unknown. Using serum samples collected in Finland from 7,961 patients suspected of having viral neurologic disease or Puumala virus infection during the summers of 2001-2013, we analyzed the samples to detect California serogroup infections. IgM seropositivity revealed 17 acute infections, and cross-neutralization tests confirmed presence of INKV or CHATV infections. All children (<16 years of age) with INKV infection were hospitalized; adults were outpatients with mild disease, except for 1 who was hospitalized with CHATV infection. Symptoms included fever, influenza-like illness, nausea or vomiting, disorientation, nuchal rigidity, headache, drowsiness, and seizures. Although many INKV and CHATV infections appear to be subclinical, these viruses can cause more severe disease, especially in children.


Assuntos
Infecções por Bunyaviridae/epidemiologia , Infecções por Bunyaviridae/virologia , Orthobunyavirus/classificação , Animais , Anticorpos Antivirais/imunologia , Infecções por Bunyaviridae/diagnóstico , Infecções por Bunyaviridae/transmissão , Finlândia/epidemiologia , Geografia , Humanos , Imunoglobulina M/imunologia , Incidência , Orthobunyavirus/genética , Orthobunyavirus/imunologia , Vigilância da População , Estudos Retrospectivos , Estudos Soroepidemiológicos , Sorogrupo
11.
PLoS One ; 9(10): e110210, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25302603

RESUMO

A new type of pyoderma was detected in Finnish fur animals in 2007. The disease continues to spread within and between farms, with severe and potentially fatal symptoms. It compromises animal welfare and causes considerable economic losses to farmers. A case-control study was performed in 2010-2011 to describe the entity and to identify the causative agent. Altogether 99 fur animals were necropsied followed by pathological and microbiological examination. The data indicated that the disease clinically manifests in mink (Neovison vison) by necrotic dermatitis of the feet and facial skin. In finnraccoons (Nyctereutes procyonoides), it causes painful abscesses in the paws. Foxes (Vulpes lagopus) are affected by severe conjunctivitis and the infection rapidly spreads to the eyelids and facial skin. A common finding at necropsy was necrotic pyoderma. Microbiological analysis revealed the presence of a number of potential causative agents, including a novel Streptococcus sp. The common finding from all diseased animals of all species was Arcanobacterium phocae. This bacterium has previously been isolated from marine mammals with skin lesions but this is the first report of A. phocae isolated in fur animals with pyoderma. The results obtained from this study implicate A. phocae as a potential causative pathogen of fur animal epidemic necrotic pyoderma (FENP) and support observations that the epidemic may have originated in a species-shift of the causative agent from marine mammals. The variable disease pattern and the presence of other infectious agents (in particular the novel Streptococcus sp.) suggest a multifactorial etiology for FENP, and further studies are needed to determine the environmental, immunological and infectious factors contributing to the disease.


Assuntos
Infecções por Actinomycetales/veterinária , Doenças dos Animais/epidemiologia , Doenças dos Animais/microbiologia , Arcanobacterium , Doenças dos Animais/diagnóstico , Animais , Arcanobacterium/classificação , Arcanobacterium/genética , Necrose/microbiologia , Necrose/patologia , RNA Ribossômico 16S/genética
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