Giving and Taking: Inaugural Lecture Mariet Feltkamp

Feltkamp is Professor of Medical Microbiology on behalf of the Sanquin Blood Supply Foundation. She also works as a clinical virologist at the LUMC, where she conducts research into viral infections in transplants. For the past three years, she has combined this with her work at Sanquin, where she focuses on bloodborne infections. The common thread is preventing viral infections transmitted through transfusions and organ transplants.

Donating and Receiving

According to Feltkamp, the title of her lecture refers to the interaction between donor and recipient. “On the one hand, people give blood or an organ; on the other hand, we must ensure that what someone receives is safe and appropriate.” At Sanquin, she therefore advises on donor selection and screening to prevent bloodborne infections.

For both blood product transfusions and organ transplants, ‘the big three’ are the most important viral infections screened for: HIV, hepatitis B, and hepatitis C. In addition, there are viruses that people notice little or nothing of, but which can be dangerous for patients with weakened immune systems. This applies, for example, to cancer patients receiving donor blood and to people using strong immunosuppressants after an organ transplant.

“For some vulnerable patients, for instance, we select blood products that must not contain parvovirus,” explains Feltkamp. That virus causes fifth disease in children. “Someone who is infected can have up to a trillion virus particles per milliliter of blood.” In organ transplants, each organ has its own specific issue. For instance, the BK virus is primarily a problem in kidney transplants. “Most people already carry this virus. Due to immunosuppressive medication, it reemerges in the donor kidney and can destroy it. Then, as a transplant patient, you are back to square one.”

The TTV virus, on the other hand, is relatively harmless. You do not get sick from it even after a transplant. “We want to use it as an indicator of immunity in transplant patients. Few virus particles can mean that the immune system needs to be suppressed more strongly to prevent rejection. With many particles, medication can actually be reduced, so that people are less vulnerable to infections.”

Climate change

Due to global warming, viral diseases that were previously not a problem are coming closer. The mosquito season is getting longer, and mosquito species that did not used to occur here, such as the tiger mosquito, will soon be buzzing around in the Netherlands as well. Feltkamp: “We are closely monitoring three viral diseases: West Nile fever, dengue, and chikungunya. These diseases already occur in Europe and sometimes appear in the Netherlands as well. For instance, holidaymakers can bring dengue and chikungunya back from Southern Europe, and we occasionally see West Nile virus appear in our country in horses and humans.”

As soon as it is known that such a bloodborne viral infection is prevalent in a specific area, Sanquin instructs donors not to donate for the first four weeks after returning from vacation. If a large area is involved, for example West Nile virus in Italy, where many donors go on holiday, Sanquin will actively screen donations from that group to avoid missing too many donations. If a virus has appeared in a specific location in the Netherlands, it is also possible to screen all donations from that part of the country.

Testing earlier

Not everyone gets sick from West Nile virus. Someone can be infected without symptoms and still donate. If that blood goes to a vulnerable recipient, they run the risk of developing severe encephalitis. “Naturally, we want to avoid that,” says Feltkamp, “and that is why it is important that we know exactly when and where West Nile virus is circulating, including in the Netherlands. Data from the field, such as infections in Dutch mosquitoes, birds, and horses, help with this, but often arrive too late. That is to say, when the mosquito season has already passed its peak and the greatest risk seems to have passed. We should actually keep a finger on the pulse ourselves by randomly measuring West Nile virus in selected donations in August and September. We can then respond to potential danger much faster and adjust donor screening accordingly.”

Collaboration

Feltkamp has been working at Sanquin for three years now, where she succeeded Hans Zaaijer. “Sanquin is a fascinating, complex organization with many products, steps, and processes. In my career as a clinical virologist, those were quite far removed from me. Fortunately, I receive a lot of support from my immediate colleagues and am gradually learning to see the forest for the trees. Without them, I would never be able to do this work at Sanquin for fifty percent of my time.”

Mariet Feltkamp’s inaugural lecture ‘Giving and Taking’ can be followed live on Monday, March 30, from 16:00 to 17:00 via the livestream on the Leiden University website.