Diagnosing Typhoid Fever

If a person has a high fever with the feeling of being unwell and thinks that he/she might have typhoid fever, it is essential to visit a Medical Doctor immediately for a proper diagnosis. It is important to understand that once typhoid fever is left untreated, it can become fatal and lead to complications (20% of people with typhoid fever complications die from the illness).

Medical Doctors confirm the diagnosis of typhoid fever through a clinical analysis of a stool sample or blood, to test for the presence of Salmonella Typhi.

It is important to confirm this diagnosis as fever and other related symptoms associated with typhoid fever are common with other diseases such as malaria and urinary tract infection.

Specific Widely Used Typhoid Tests: Widal Test

The Widal test was the mainstay of typhoid fever diagnosis for decades. It is used to measure agglutinating antibodies against H and O antigens of S. typhi. Neither sensitive nor specific, the Widal test is no longer an acceptable method of diagnosis.

In developed countries, the use of the Widal test as a laboratory tool to aid in the diagnosis of typhoid fever during the acute phase of the illness has largely been abandoned, as the need for such a test is minimal, especially given the low prevalence of typhoid fever. In addition, better means of isolating the organism from samples are available. Unfortunately, in some developing countries such as Nigeria, the situation is quite different, and the Widal test appears to be the only laboratory means employed in the diagnosis of typhoid fever among suspected patients. Therefore, the diagnosis of typhoid fever based on the use of the Widal Test alone is frequently inaccurate as positive titers can occur in malaria and other infections.

The Widal test cannot be expected to give a reliable diagnostic result in endemic regions for the following reasons:

• The inherent variability of the test
• Difficulty in establishing a steady-state baseline titer for the patients
• Repeated exposures to typhi in endemic regions
• Cross-reactivities with other non-Salmonella organisms
• Lack of reproducibility of the test result by the physician

The function of the laboratory is to perform and report the test result to the requesting medical doctor, who in turn will use the data to help make the proper diagnosis. Unfortunately, in several areas of developing countries, the laboratory performs the test, makes the diagnosis, and prescribes antibiotics. Next time one is diagnosed as having typhoid, and the test was from the Widal test alone, it may not be correct. Blood culture and bone marrow biopsy is the good standard for diagnosis.

Treatment of Typhoid Fever

Typhoid fever can be treated with antibiotics. If typhoid fever is diagnosed early, the infection is likely to be mild and can usually be treated at home with a 7- to 14-day course of antibiotic tablets.

More severe typhoid fever usually requires admission to the hospital so antibiotic injections can be given. With prompt antibiotic treatment, most people start to feel better within a few days and serious complications would be avoided.

Drug resistance is common with the likelihood of more complicated and expensive treatment options required in most endemic areas. Without symptoms, certain persons continue to be carriers of typhoid bacteria, and can spread to others through the shedding of bacteria in their faeces

It is important for people being treated for typhoid fever to do the following:

• Take prescribed antibiotics for as long as it has been prescribed.
• Wash hands with soap and water after using the bathroom and avoid preparing or serving food for other people. This lowers the chance of passing the infection on to another person.

Commonly Prescribed Antibiotics

Antibiotics prescribed for typhoid fever are dependent on where the bacteria infected the person -bacterium stains can respond better or worse to certain antibiotics, and these medicines can be used together or alone.

Antibiotics that may be given for typhoid fever are:

Fluoroquinolones: These antibiotics, including ciprofloxacin (Cipro), may be a first choice. They stop bacteria from copying themselves. But some strains of bacteria can live through treatment. These bacteria are called antibiotic-resistant.

Cephalosporins: This group of antibiotics keeps bacteria from building cell walls. One kind, ceftriaxone, is used if there is antibiotic resistance.

Macrolides: This group of antibiotics keeps bacteria from making proteins. One kind called azithromycin (Zithromax) can be used if there is antibiotic resistance.

Carbapenems: These antibiotics also prevent bacteria from building cell walls. But they focus on a different stage of that process than the cephalosporins. Antibiotics in this category may be used with severe disease that doesn't respond to other antibiotics.

Prevention Of Typhoid Fever

Typhoid fever can be prevented by following these methods

Safe Water

Typhoid fever is a waterborne disease and the main preventive measure is to ensure access to safe water. During outbreaks of typhoid fever, the following control measures are of particular interest:

• From Water Source in Urban Areas: The control and treatment of water supply systems must be strengthened from catchment to consumer. Safe drinking water should be made available to the population through a piped system or from clean water tank trucks.
• From Wells and Streams in Rural Areas: Wells used in villages and other rural communities must routinely be treated as necessary. Treatment should be with chlorine or other water treatment antiseptics.
• In Homes: Important attention must be paid to the disinfection and the storage of water. Drinking water can be made safe by boiling or adding a chlorine-releasing chemical. Storage facilities such as narrow-mouthed pots with covers are helpful in the reduction of typhoid fever transmission

Food Safety

Contaminated food is another important vehicle for typhoid fever transmission. Appropriate food handling and processing are important, and the following basic hygiene measures must be implemented or reinforced during typhoid fever outbreaks:

• Washing hands with soap before preparing or eating food
• Avoiding the consumption of raw food, shellfish, and ice
• Eating only freshly cooked food that is still piping hot or reheating food when it is cold
• Screening of restaurant (food service) workers. They are screened with Widal tests anti-vi. If they are positive, they are treated with a high dose of Amoxil for 4 weeks

Sanitation

Proper sanitation contributes to reducing the risk of transmission of all diarrheal bacteria including Salmonella typhi.

• Appropriate facilities for human waste disposal must be available for the community. In an emergency, pit latrines can be quickly built.
• Collection and treatment of sewage, especially during the rainy season, must be implemented
• In areas where typhoid fever is known to be present, the use of human excreta as fertilizers must be discouraged.
• Open defecation must be discouraged as much as possible.

Vaccination

Vaccination is an additional effective tool for the prevention of typhoid fever. Currently, 3 types of typhoid vaccines are licensed for use:

• Typhoid conjugate vaccine (TCV)
• Unconju­gated Vi polysaccharide (ViPS)
• Live attenuated Ty21a vaccines

The second and third types have been recommended by The World Health Organization (WHO) since 2008 for the control of typhoid in endemic and epidemic settings.