Despite good access to effective antibiotics, Streptococcus pneumoniae (pneumococci) is still a major cause of disease and death in both developing and developed countries. Pneumococci are the main cause of bacterial respiratory tract infections, such as pneumonia, middle ear infection, and sinusitis, in all age groups.
Fleas are ectoparasitic blood-sucking insects with the ability to jump, which commonly infest wild and domestic animals (mainly dogs and cats) but also humans.
Hepatitis C is a liver disease caused by infection with the hepatitis C virus (HCV). HCV can cause both acute and chronic hepatitis infection, ranging in severity from a mild illness that lasts only a few weeks to a serious, lifelong illness resulting in cirrhosis and liver cancer.
Dengue is a mosquito-borne viral disease widely spread in tropical and subtropical regions. It is transmitted by Aedes mosquitoes. Most of the clinical cases present a febrile illness, severe forms include hemorrhagic fevers and shock with fatalities.
Plague is caused by the bacillus Yersinia (Y.) pestis, belonging to the family of the Enterobacteriaceae. It evolved several thousand years ago from Y. pseudotuberculosis.