Streptococcus suis is a bacterium that threatens the health and well-being of pigs. S. suis infections are one of the most common reasons for the use of antibiotics in pig farming, particularly around weaning age. S. suis can cause serious symptoms and lead to meningitis, joint inflammation, blood poisoning and even death. Currently there is no vaccine available that effectively protects against all S. suis infections. Vaccines based on killed S. suis bacteria only protect against the same serotype. Because there is a great need for a vaccine that protects against the most important serotypes, Wageningen Bioveterinary Research is collaborating closely with industry to develop such a vaccine.