Salmonella typhi is a pathogenic bacterium which causes typhoid fever in human beings.
Bacteria like Streptococcus pneumoniae and Haemophilus influenzae are responsible for the disease, pneumonia, in humans which infects the alveoli (air filled sacs) of the lungs.
Wuchereria, the filarial worms, cause a slowly developing chronic inflammation.
Various species of Plasmodium are responsible for different types of malaria.