Streptococcus pneumoniae is a bacterial pathogen that is one of the most common bacterial pathogens of the respiratory system. The main models of transmission of Streptococcus pneumoniae are direct contact between two persons, where the transmission occurs through respiratory droplets. The transmission can also happen through an autoinoculation process in a person who carries the bacteria in the upper part of the respiratory tract. According to Marquart, in the context of virulence, “the movement of S. pneumoniae to the lungs, blood, or other sites can instigate responses by the bacteria that result in their proteases” (2021, p. 1). The diseases commonly associated with the Streptococcus pneumoniae are pharyngitis and tonsillitis.
Herpes simplex virus is a virus that causes an eye infection in the form of the cornea. The herpes simplex virus is commonly transmitted through oral-to-oral contact between two people. However, as the herpes simplex virus is transmitted by contact with all surfaces in or around the mouth, including saliva, the disease can potentially be transmitted through contact with genital areas. Herpes simplex virus virulence factors include ICP 34.5, an infected cell protein that participates in replication and inhibition processes. The disease commonly associated with the herpes simplex virus in the eye system is herpes simplex keratitis.
Protozoan pathogens are an example of eukaryotic pathogens that involve parasites. The protozoan virulence factors are analogous to viral pathogens, which include adhesins, toxins, and antigenic variation. The associated disease is loiasis, a disease caused by parasitic worms in Africa who infect the skin. The disease is transmitted through bites of mango flies that inhabit the rainforests regions of West and Central Africa. According to Buell et al. (2019), loiasis is a significant public health burden across Central Africa.
References
Marquart, M. E. (2021). Pathogenicity and virulence of Streptococcus pneumoniae: Cutting to the chase on proteases. Virulence, 12 (1), 766-787. Web.
Buell, K.G., Whittaker, C., Chesnais, C.B., Jewell, P.D., Pion, S. D. S., Walker, M., Basáñez, M., & Boussinesq, M. (2019). Atypical clinical manifestations of Loiasis and their relevance for endemic populations. Open Forum Infectious Diseases, 6 (11), 1-9. Web.