Search bioRxiv⌕ Search

Biology subjects

van den Brand, J. M. A.

Publications and source records attributed to van den Brand, J. M. A..

3 recordsLinked to original sources

West Nile virus and Usutu virus in wild birds from Rescue Centers, a post-mortem monitoring study from Central Italy.

West Nile virus (WNV) and Usutu virus (USUV) are mosquito-borne flaviviruses causing world-wide numerous cases in animals and humans. In Italy, both viruses have been associated with neurological diseases in humans and wild birds. Wild bird rescue centers where support in emergency and care of diseased animals are provided, are potential significant hot spots for avian infection surveillance, as recognized in the Italian Integrate National Surveillance Plan for Arboviruses. Here we report the results of a post-mortem active monitoring study conducted from November 2017 to October 2020 on animals hosted in five wild bird rescue centers of Central Italy. Five hundred seventy-six (n = 576) wild birds were tested by real-time polymerase chain reaction (RT-PCR) for the presence of WNV or USUV RNA fragments. No birds tested positive for USUV RNA (n = 0; 0.00 %). Evidence of WNV RNA (Ct value = 34.36) was found in one bird (n = 1; 0.17 %), an adult little grebe (Tachybaptus ruficollis subsp. ruficollis), that tested WNV positive on December 2019 and died due to traumatic injuries. The main pathological findings consisted in mild CD3+ lymphocytic tubulo-interstitial nephritis, meningoencephalitis, and cardiomyocytes loss and interstitial oedema of the heart. This study highlights the strategic role of wildlife rescue centers in monitoring both the introduction and circulation of avian emerging zoonotic diseases. Also, the presence of WNV during the cold season evidences the possible role of birds in overwintering mechanisms in the Italian territory and requires further investigations.

microbiology↗

Efficient direct and limited environmental transmission of SARS-CoV-2 lineage B.1.22 in domestic cats

Susceptibility of domestic cats for infection with SARS-CoV-2 has been demonstrated by several experimental studies and field observations. We performed an extensive study to further characterize transmission of SARS-CoV-2 between cats, both by direct contact as well as by indirect contact. To that end, we estimated the transmission rate parameter and the decay parameter for infectivity in the environment. Using four groups of pair-transmission experiment, all donor (inoculated) cats became infected, shed virus and seroconverted, while three out of four direct contact cats got infected, shed virus and two of those seroconverted. One out of eight cats exposed to a SARS-CoV-2-contaminated environment became infected but did not seroconvert. Statistical analysis of the transmission data gives a reproduction number R0 of 2.18 (95% CI: (0.92-4.08), a transmission rate parameter {beta} of 0.23 day-1 (95% CI: 0.06-0.54), and a virus decay rate parameter of 2.73 day-1 (95% CI: 0.77-15.82). These data indicate that transmission between cats can be sustained (R0>1), however, infectiousness of a contaminated environment decays rapidly (mean duration of infectiousness 1/2.73 days). Infections of cats via exposure to a SARS-CoV-2-contaminated environment cannot be excluded if cats are exposed shortly after contamination.

microbiology↗

Influenza infection in ferrets with SARS-CoV-2 infection history

Non-pharmaceutical interventions (NPIs) to contain the SARS-CoV-2 pandemic drastically reduced human-to-human interactions, decreasing the circulation of other respiratory viruses as well. As a consequence, influenza virus circulation - normally responsible for 3-5 million hospitalizations per year globally - was significantly reduced. With downscaling the NPI countermeasures, there is a concern for increased influenza disease, particularly in individuals suffering from post-acute effects of SARS-CoV-2 infection. To investigate this possibility, we performed a sequential influenza H1N1 infection 4 weeks after an initial SARS-CoV-2 infection in the ferret model. Upon H1N1 infection, ferrets that were previously infected with SARS-CoV-2 showed an increased tendency to develop clinical symptoms compared to the control H1N1 infected animals. Histopathological analysis indicated only a slight increase for type II pneumocyte hyperplasia and bronchitis. The effects of the sequential infection thus appeared minor. However, ferrets were infected with B.1.351-SARS-CoV-2, the beta variant of concern, which replicated poorly in our model. The histopathology of the respiratory organs was mostly resolved 4 weeks after SARS-CoV-2 infection, with only reminiscent histopathological features in the upper respiratory tract. Nevertheless, SARS-CoV-2 specific cellular and humoral responses were observed, confirming an established infection. Thus, there may likely be a SARS-CoV-2 variant-dependent effect on the severity of disease upon a sequential influenza infection as we observed mild effects upon a mild infection. It, however, remains to be determined what the impact is of more virulent SARS-CoV-2 variants. ImportanceDuring the COVID-19 pandemic, the use of face masks, social distancing and isolation were not only effective in decreasing the circulation of SARS-CoV-2, but also in reducing other respiratory viruses such as influenza. With less restrictions, influenza is slowly returning. In the meantime, people still suffering from long-COVID, could be more vulnerable to an influenza virus infection and develop more severe influenza disease. This study provides directions to the effect of a previous SARS-CoV-2 exposure on influenza disease severity in the ferret model. This model is highly valuable to test sequential infections under controlled settings for translation to humans. We could not induce clear long-term COVID-19 effects as SARS-CoV-2 infection in ferrets was mild. However, we still observed a slight increase in influenza disease severity compared to ferrets that had not encountered SARS-CoV-2 before. It may therefore be advisable to include long-COVID patients as a risk group for influenza vaccination.

pathology↗