Disease at a Glance – Typhoid Fever
Typhoid Fever is a type of enteric fever that’s caused by Salmonella Typhi bacteria. Other enteric group fevers include Paratyphoid A, Paratyphoid B and Paratyphoid C, which are caused by Salmonella Paratyphi A, B & C, respectively. An estimated 22 million cases of typhoid fever occur worldwide each year – an additional 6 million cases of paratyphoid fever are also reported each year. The risk for Typhoid Fever is the highest in South Asia, but the disease it’s relatively common in most developing nations.
Human beings are the only source of Salmonella Typhi. Typhoid Fever is transmitted through the faeco-oral route i.e. ingestion of food or water contaminated by the faeces (or stool) of an infected person or a carrier of the disease. A carrier is someone who has either recovered from the disease but continues to carry the bacteria or someone who is infected with the bacteria but doesn’t show any outwardly symptoms of the disease. Both the infected person and the carrier shed Salmonella Typhi in their faeces.
|Fever, that starts slow, but soon rises to 103-104 degree farenheit|
|Weakness & fatigue|
|Loss of appetite|
|Rose-coloured spots or rash on the abdomen or chest may appear after a week|
One can get Typhoid Fever by eating food or drinking a beverage that’s been handled by a person who is shedding Salmonella Typhi or if sewage contaminated with the bacteria gets into the water used for drinking or washing food. This is the reason why Typhoid Fever is more common in areas where hand washing is less frequent and where water is likely to be contaminated with sewage. Another common source of transmission is through infected food handlers.
The normal incubation period of Typhoid Fever is 6 to 30 days. The onset of the disease is insidious with increasing fatigue, fever, headache, malaise and lack of appetite. Rose-coloured spots or rashes on the abdomen and chest may appear around the seventh day of the fever. If the disease is left untreated, serious life-threatening complications like intestinal haemorrhage or perforation can occur after 2-3 weeks.
By studying the clinical features of the case a provisional diagnosis can be made, but for conformation diagnostic investigations are required. In the first and second week (after onset of fever), a blood culture is advised, while a serological test known as Widal is recommended in the second week. In the third and fourth week, a stool and urine culture is required to confirm the disease.
Treatment by specific antibiotics will shorten the course of the disease and cure the patient, but it may require 3-5 days for the fever to subside completely. Typically, an antibiotic sensitivity test is done to ensure that the prescribed drugs aren’t resistant to Salmonella Typhi. Vaccines are recommended in endemic areas as a preventive measure; good personal hygiene is also equally important.
1. Centres for Disease Control and Prevention (www.cdc.gov)
2. World Health Organization (www.who.int)
3. US National Library of Medicine (www.nlm.nih.gov)