The role of pets in pandemic research: An interview with veterinarian Simone Schuller

Pets played an unexpected role during the pandemic. Initially, it was unclear whether they could spread viruses, but it soon became clear that cats could pass on the coronavirus. This realization led to a more intensive study of pets to obtain a more comprehensive picture of infection pathways. Simone Schuller, co-leader of the BEready cohort study and veterinarian, provides insights into the research work and the initial results of the pilot study in an interview.

Text by Emily Lim

What role did pets play during the pandemic and how did the idea for this study come about?

At the beginning of the pandemic, it was unclear whether pets played a role in the spread of SARS-CoV-2. It soon became clear that cats can become infected with SARS-CoV-2 and pass it on. This made us realise that pets that live closely with humans can contribute to the spread of viruses. Pets are part of many families and were still in contact with the outside world during the lockdown. We therefore decided to include animals in our research to get a more comprehensive picture.

What are the transmission routes of pathogens between animals and humans?

Some parasites such as Echinococcus in dogs or Toxoplasma in cats are excreted in faeces and can infect humans in this way. Multi-resistant germs, which are difficult to treat, can also be transmitted from animals to humans. Hygiene is therefore particularly important, especially after contact with animal faeces or urine.

What hygiene measures do you recommend preventing the transmission of pathogens from animals to humans?

Basic hygiene measures such as washing hands after contact with faeces or urine are essential. In addition, pet bowls should not be cleaned with the owner's dishes and animals should not eat from the owner's plate. It is also advisable not to let animals lick your face and to consider whether the animal should sleep in your bed to avoid possible contamination. Pregnant women should be particularly careful and have someone else clean the litter tray to minimise the risk of toxoplasmosis infection.

What impact has the pandemic had on decisions made and how could they have been different with more data?

At the beginning of the pandemic, many decisions were made without having enough data. Measures were taken that later turned out to be too drastic or insufficient. The approach was slow and at some point, more informed decisions were made. With a comprehensive cohort study, we hope to create a basis for making better decisions in the early stages of a pandemic. By analysing archived samples, we can detect changes in the spread of pathogens at an early stage and thus make informed decisions.

What health conditions did you observe in the animals in the BEready cohort during the pilot study?

Most of the animals were healthy, although some were slightly overweight, which is not a serious illness. The owners take great care of their animals' health, including preventive measures such as deworming and vaccinations. This reduces the risk of zoonotic diseases - i.e. diseases that can be transmitted from animals to humans.

How do you collect samples from animals and which animals are included in your study?

We only collect blood samples from dogs and cats, as this is difficult with smaller animals. Swabs and faecal samples are also taken from smaller animals. Farm animals are not currently included but could be relevant in the future as they also have close contact with humans. The decision to include only pets for the time being is based on the feasibility and scope of the study.

How does the stress caused by examinations affect the animals in the cohort?

Stress depends heavily on the socialisation and individual temperament of the animals. Some animals react calmly to transport and examinations, while others are stressed. We try to minimise stress through a calm environment and gentle handling. If an animal is too stressed, we refrain from taking invasive samples and concentrate on non-invasive examinations and discussions with the owners.

Can contact with animals have a positive effect on the immunity of their owners?

Yes, there are various aspects that speak in favour of this. Studies show that children who grow up in the countryside and have contact with animals are less likely to suffer from asthma. This could be since the immune system is better trained through contact with animals. In addition, dog owners must go for regular walks, which brings exercise, fresh air and sunlight - all factors that strengthen the immune system. Emotional contact with animals also reduces stress, which also has a positive effect on the immune system. However, it is not enough to say that pet owners are generally healthier, there are many factors that contribute to a healthy lifestyle.

The inclusion of pets in cohort studies to investigate pandemics and infectious diseases is an important step towards obtaining more comprehensive data on human-animal transmission. The knowledge gained from this can help to make informed decisions and better protect the health of both humans and animals.