Chain of Infection

Chain of Infection

Name

Institution

Chain of Infection

Cholera is one of the re-emerging infectious diseases facing the world today. Although most of the developed world has managed to eliminate the infection, many parts of the developing world are still struggling with the disease. The agent responsible for the infection affects the intestines and this causes the infection. It can be a cause of death if not treated on time. People with severe infections lose a lot of body fluid because of the profuse watery diarrhea and vomiting. This can lead to dehydration and subsequent shock. The causative agent is vibrio cholerae. The agent is a gram-negative bacterium. The serogroups responsible for spreading the infection are O1 and O139. O1 serogroup includes the biotypes El Tor and classical. These biotypes are divided further into Inaba and Ogawa. The classical biotype is associated with the earlier cases of cholera that cause pandemics while the El Tor is associated with modern day infections. The serogroup O139 appeared in 1992 and it was responsible for the cholera outbreaks at the time (Nelson et al., 2013).

Humans are the main host for vibrio cholerae. Susceptible hosts are vulnerable to the disease. They include people with low immune systems such as the elderly and cancer patients. Children are vulnerable to infections as well, especially if they are malnourished. Although there are no known animal hosts for the bacteria, it attaches itself to the shells of crabs and shrimps. This can cause infections to humans when they are consumed raw or when they are not cooked properly. The primary mode of transmission is ingestion. People can get the infection when they eat foods or take water that contains the vibrio cholerae. The agents thrive well in brackish and marine waters. They are also present in the feces of someone who has cholera. They can be found in food sources contaminated by these feces. Cholera is most likely to be present in areas where there is poor hygiene and untreated water and sewage.

Chain of infection

Etiological agent: vibrio cholerae

Reservoir: the usual habitats for the vibrio cholerae are human beings and the environment. The agent can survive in humans as well as in aquatic environments. They can survive and multiply with the zooplankton and phytoplankton (Sack et al., 2004).  

Portal of exit: the agent escapes from the human reservoirs through excretion. The agents in aquatic environment escape through shellfish. Another portal of exit from the environment is the consumption of the contaminated water

Mode of transmission: the main mode of transmission is through the ingestion of foods and drinks that are contaminated with the agent. Transmission can also happen from one person to another. This happens in severe cases. The person taking care of a patient can get the infection if he touches anything that is infected. The patient can become a carrier

Portal of entry: the portal of entry for vibrio cholerae is the mouth

Surveillance

Cholera outbreaks can spread quickly especially in areas where people lack basic knowledge about the disease. Active surveillance will be most appropriate for this situation. One collects data from multiple sources including individuals in the community, institutions, and healthcare facilities. Cholera can spread because of movement. People will benefit more from active surveillance. Collecting data from door to door enables one to determine the number of people affected as well as those who are at risk of infection. Data from the healthcare facilities can direct a person on the areas to focus on when collecting the data. This will be important because it will ensure that the proper mechanisms are taken to avoid the spread of the disease.

References:

CDC (2014). Cholera – vibrio cholerae infection. Centers for Disease Control and Prevention. Retrieved from http://www.cdc.gov/cholera/infection-sources.html

Nelson, J. E., Harris, B. J., Morris, G. J., Calderwood, B. S., & Camili, A. (2009). Cholera transmission: The host, pathogen and bacteriophage dynamic. Nature Reviews Microbiology, 7(10), 693-702

Sack, A. D., Sack, B. R., Nair, B., & Siddique, K. A. (2004). Cholera. The Lancet, 363, 223-233