Connect with us

News

SARS-CoV-2–Specific Antibodies in Domestic Cats during First COVID-19 Wave, Europe – The Maravi Post

Published

on


Disclaimer: Early release articles are not considered as final versions. Any changes will be reflected in the online version in the month the article is officially released.

Author affiliations: University of Veterinary Medicine Hannover, Hannover, Germany (C. Schulz, M. Mirolo, H. Volk, M. Gonzalez-Hernandez, F. Kaiser, M. von Köckritz-Blickwede, A. Osterhaus); Artemis One Health Research Foundation, Delft, the Netherlands (B. Martina, M. Mirolo); LABOklin, Kissingen, Germany (E. Müller, R. Klein); Utrecht University Faculty of Veterinary Medicine, Utrecht, the Netherlands (H. Egberink)

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the ongoing coronavirus disease (COVID-19) pandemic, causes high rates of illness and death among humans. SARS-CoV-2 is a newly recognized member of the genus Betacoronavirus, family Coronaviridae, that infects humans. An early serosurvey among domestic cats in Wuhan, China, during January–March 2020 reported 14.7% seropositivity (1). Experimental infections demonstrated susceptibility to SARS-CoV-2 infection in cats and other carnivore species, such as ferrets (Mustela putorius furo), minks (Neovison vison), and to a lesser extent domestic dogs (2,3), and confirmed anecdotal observations of naturally occurring human-to-animal transmissions (4,5). Respiratory and gastrointestinal signs were observed in SARS-CoV-2–infected cats (68). We conducted a seroprevalence study for SARS-CoV-2–specific antibodies among domestic cats in Europe during and after the first COVID-19 pandemic wave, using a plaque-reduction virus neutralization test (VNT) and a SARS-CoV-2 receptor-binding domain–specific ELISA (RBD-ELISA).

The Study

We analyzed serum samples collected from 2,160 domestic cats during April–June 2020. Samples had been sent to a veterinary diagnostic laboratory (LABOklin; Kissingen, Germany) for diagnostic purposes unrelated to suspicion of SARS-CoV-2 infection (9). Samples were from 1,136 cats in Germany, 331 in the United Kingdom, 333 in Italy, and 360 in Spain. Among 1,799 samples with demographic data, cats ranged from 0.1–23 years of age (median and mean age 11 years). We estimated a minimum of 300 total samples per location to enable a realistic estimation for each location. To confirm specificity of the assays to detect SARS-CoV-2–specific antibodies, we included 25 prepandemic cat serum samples and 25 serum samples from cats that tested positive for feline coronavirus/feline infectious peritonitis (FCoV/FIP) by NovaTec VetLine (Novatec Immundiagnostica GmbH, https://www.novatec-id.com), a commercial antibody test, in the screening.

We tested all serum samples by VNT, as previously described (10). We considered serum samples positive when titers were >20, expressed as the reciprocal of the dilution that gave >80% reduction of stained cells in the plaque reduction neutralization test (PRNT80) (Appendix).

We also tested serum samples with an indirect ELISA we developed and validated inhouse. We used an ELISA previously used for detecting SARS-CoV-2 RBD antibodies in human serum (11) and replaced the anti-human IgG conjugate with an anti-cat IgG conjugate (Appendix).

We evaluated performance characteristics of the cat ELISA-RBD by using Pearson correlation of the results obtained by ELISA-RBD and Gaussian distribution analyses for the VNT. We also calculated diagnostic sensitivity and specificity of the ELISA-RBD compared with VNT. We conducted data analyses using R (R Foundation for Statistical Computing, https://www.r-project.org) and Prism version 9 (GraphPad Software Inc., https://www.graphpad.com). We calculated SARS-CoV-2 seroprevalence in cats separately for each country.

Figure

Figure. Overall seroprevalence of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies in 2,160 domestic cats, by month and country, during the first coronavirus disease pandemic wave, Europe, April–August 2020. Numerals…

We found overall SARS-CoV-2 seroprevalence among cats was 4.2% in Germany, 3.3% in the United Kingdom, 4.2% in Italy, and 6.4% in Spain (Table 1; Figure). Among all 2,160 cat serum samples tested, 96 (4.4%, 95% CI 3.6%–5.4%) were positive by VNT and 92 (4.3%, 95% CI 3.4%–5.2%) by RBD-ELISA. The RBD-ELISA showed a diagnostic sensitivity of 90.6% (95% CI 90.0%–91.2%) and specificity of 99.8% (95% CI 99.8%–99.8%) compared with VNT (Table 2). Furthermore, correlation (r = 0.9, 95% CI 0.9–0.9) and Gaussian distribution analyses (r2>0.7) revealed high agreement between VNT and RBD-ELISA sensitivities. All 25 prepandemic serum samples and 25 FCoV/FIP-positive samples tested SARS-CoV-2–negative in both the VNT and RBD-ELISA (data not shown), confirming the specificity of the assay for measuring SARS-CoV-2–specific antibodies.

Our study of domestic cat serum from 4 selected countries showed that during the first COVID-19 wave in Europe, >4% of domestic cats had been infected with SARS-CoV-2, probably through their contacts with infected humans. Because serum samples were sent to the veterinary diagnostic laboratory for conditions unrelated to a suspected SARS-CoV-2 infection, our data might not fully represent the overall seropositivity of the domestic cat population in Europe.

We used a VNT and an RBD-ELISA based on the original SARS-CoV-2 wild-type isolate (Wuhan-Hu-1, GenBank accession no. MN908947.3). The RBD-ELISA proved to have a high sensitivity and specificity compared with the VNT (Table 2), but 5 low-titer (titer = 20) VNT-positive samples remained undetected by the RBD-ELISA. These samples might have remained undetected because of the high specificity of RBD-ELISA, which detects antibodies toward the single spike protein ectodomain. Unlike RBD-ELISA, VNT might identify a broader range of virus neutralizing antibodies, including those directed against other domains of the spike protein. Of note, the only correlation of virus protection we have to date is virus neutralization, which apparently correlates well with RBD-ELISA positivity. For serologic screening and for individual diagnostic testing of domestic cats, the RBD-ELISA could replace the VNT, thus avoiding the use of live SARS-CoV-2 under Biosafety Level 3 laboratory conditions. We further confirmed specificities of the VNT and RBD-ELISA by showing that prepandemic and FCoV/FIP-positive cat serum samples were negative in both assays. This finding excluded the detection of cross-reactive antibodies against feline alphacoronaviruses (4) and alphacoronaviruses of other animal species that might infect cats (4,12). Our data contrast a heavily affected area in China at the onset of the pandemic from which seropositivity levels of domestic cats ranged <15% (1), although those results were from relatively fewer tested cats and used a different assay.

Conclusions

During the first COVID-19 pandemic wave, reported seroprevalence levels in domestic cats ranged from 0.4% in the Netherlands (4) to 23% among cats in COVID-19–positive households in France (13). Similar seroprevalence levels in cats and humans in the same areas found by us and others suggest that in the absence of another known source (4,13; C. Schulz, unpublished data) (Appendix Table), SARS-CoV-2 infections in cats are most likely due to human-to-cat contact transmission.

Most natural SARS-CoV-2 infections of cats appear to run a mild or subclinical course, with respiratory or gastrointestinal clinical signs reported in confirmed natural infections (68). Evidence from experimental studies suggests that cats are susceptible to SARS-CoV-2 infection and can maintain the virus within a cat population and spill the infection backward or forward to other species (2,3,14). However, no evidence of cat-to-human transmission, nor of cat-specific mutations or variants of SARS-CoV-2, has been detected thus far (8,12,15). This finding contrasts reports on minks kept in farms, where mink-to-human spillback infections and mink-specific mutations have been reported (5). Although no evidence currently suggests that domestic cats play a role in the epidemiology of human SARS-CoV-2 infection, clinicians and veterinary practitioners should recommend that SARS-CoV-2–infected persons avoid close contact with their domestic cats and practice the same nonpharmaceutical prevention measures toward cats as they do to prevent human-to-human infection.

Dr. Schulz is a postdoctoral researcher at University of Veterinary Medicine Hannover, Hannover, Germany. Her research interests include the pathogenesis and epidemiology of emerging and vectorborne diseases. Dr. Martina is a senior researcher at Artemis One Health Research Foundation, Delft, the Netherlands. His research interests include the pathogenesis of and intervention strategies against emerging virus infections.

Top

The conclusions, findings, and opinions expressed by authors contributing to this journal do not necessarily reflect the official position of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors’ affiliated institutions. Use of trade names is for identification only and does not imply endorsement by any of the groups named above.

News

Solomon Islands Tension – The Maravi Post

Published

on

By


8 hours ago

Three bodies were found in a burnt out building in Honiara amid this week’s violence in the capital of the Solomon Islands, Australian media reported. Authorities had put a curfew in place on Friday night in an attempt to stem the unrest and the situation seemed to be calmer on Saturday. But the government showed no signs of addressing the underlying grievances that sparked two days of riots, including concerns about the country’s increasing links with China. Solomon Islands Prime Minister Manasseh Sogavare sought to deflect attention from domestic issues by blaming outside interference for stirring up the protesters, with a thinly veiled reference to Taiwan and the United States. Honiara’s Chinatown and its downtown precinct were focuses of rioters, looters and protesters who demanded the resignation of Sogavare, who has been prime minister intermittently since 2000. Sogavare has been widely criticized by leaders of the country’s most populous island of Malaita for a 2019 decision to drop diplomatic ties with Taiwan in favor of mainland China. His government, meanwhile, has been upset over millions in U.S. aid promised directly to Malaita, rather than through the central government. Those issues are just the latest in decades of rivalry between Malaita and Guadalcanal, where the capital, Honiara, is located, said Jonathan Pryke, director of the Sydney-based Lowy Institute think tank’s Pacific Islands program. The Solomon Islands, with a population of about 700,000, are located about 1,500 kilometers (1,000 miles) northeast of Australia.

More about

Source: Africanews



Continue Reading

News

Immunology professor talks about the new coronavirus variant – The Maravi Post

Published

on

By


Passengers at Johannesburg’s O.R Tambo airport scrambled this Saturday to find flights to Europe as more and more countries are shutting doors to passengers coming from African countries.

The emergence of the new coronavirus Omicron variant in South Africa sparked a worldwide reaction.

Professor of Immunology Danny Altmann explains.

“I know it feels very harsh to people in South Africa who have really done the right thing and been terribly speedy and vigilant in their reporting. But I just feel that we were so slow to act on Delta and the whole world paid such a high price for it. Let’s try and be forewarned and do it properly this time. So, I think it probably is warranted”, said the academic working at Imperial College London.

Last minute PCR tests are now mandatory.

The UK-based professor believes that vaccination still offers protection against the worst effects of this disease.

“I think it’s a case of kind of hope for the best and fear the worst, isn’t it? So in some ways, if you look at the straight molecular biology limitations, it looks potentially quite a lot scarier even than Delta. And don’t forget, we thought of Delta. I certainly thought Delta as a peak variant, and probably it couldn’t get much worse than that. This looks potentially worse. On the other hand, there’s no reporting from South Africa yet that cases are more severe, and it looks like vaccines may still be doing something because we heard there yesterday that the people in hospital tended to be the unvaccinated people rather than the vaccinated”, said Professor Altmann.

In Africa vaccination rates are significantly lower compared to Europe, the United States and other regions.

According to Professor Altmann, distribution of vaccines throughout Africa is essential to stop future variants.

“You know, in this particular case, if it did come out of Botswana and or South Africa, there has been quite a lot of vaccine available there. But as you say in the African continent as a whole, they’ve been very short of vaccines compared to Europe or North America. And things like this demonstrate how foolhardy that is. We’re just breeding the future variants to come and haunt us. Why do it?”

The latest available data indicate that South Africa has registered almost 3 million cases of Covid-19 and close to 90,000 deaths.

Source: Africanews

Continue Reading

News

Hawkeye Marvel Movie 2021 Release Date, Where To Watch Online Streaming on Disney+ Hotstar

Published

on

By


The ‘Hawkeye’ is the latest release which is in the limelight because of the story. As per the details, the stream of this film is available on several platforms that we going to discuss here. After the release of ‘Hawkeye’, there are many peoples who waiting for it.

Hawkeye’ 2021 Online Free

We can tell the way from which you will be able to watch the streaming of this brilliant movie. So let’s begin the article which is important to know and you will get all the details. We will explore all the things and solve your queries regarding ‘Hawkeye’ streaming.

Hawkeye Marvel Movie 2021 Release Date

Talking about the cast then we want to tell you some information. There are many things. There are several names of star cast which is definitely important to be discussed and we will tell you briefly about it. This star cast will become the reason behind its upcoming popularity. If you want to know the details then you will see an amazing level of popularity in the upcoming days.

  • Jeremy Renner as Clint Barton / Hawkeye
  • Hailee Steinfeld as Kate Bishop / Hawkeye
  • Vera Farmiga as Eleanor Bishop
  • Fra Fee as Kazi
  • Tony Dalton as Jack Duquesne
  • Zahn McClarnon as William Lopez
  • Alaqua Cox as Maya Lopez / Echo
  • Florence Pugh as Yelena Belova / Black Widow
  • How many episodes is Hawkeye?
  • Hawkeye consists of six episodes.

The film was released and on the official platform of the movies. It got an amazing level of popularity over the period of time. After the release, there are many fans appear who eagerly want to watch the story on their screen. Currently, it is getting such huge popularity over the period of time. Definitely you check on IMDB.

Now comes the very important detail which is about how to watch the live stream of the movies. So on the basis of available details, you can watch the streaming on Amazon prime video.

Also, you can rate the movie and share your feedback regarding the entertainment how much enjoyed it. However, if you want to watch it for free then must be you can bookmark the page in your browser. So stay tuned with us and get all the details.



Source link

Continue Reading

Trending

Copyright © 2020 PRUMETRICS