Typhoid and paratyphoid

Typhoid is an infectious disease caused by a subgroup of certain salmonella bacteria.

The bacteria are mainly transmitted by contaminated drinking water and food.

Good hygiene conditions in Germany mean that typhoid is extremely rare here. Most cases involve long-distance travelers who have been infected in high-risk areas in Asia.

There are two types of typhoid:

• Typhoid fever: also known as enteric fever or simply typhoid for short. This is by far the more dangerous form.
• Paratyphoid: this has similar symptoms to typhoid but is less serious.

Typhoid must always be treated with suitable antibiotics as it can lead to life-threatening complications.

Typhoid and paratyphoid develop in a very similar way.

However, the incubation period, i.e. the period between a person becoming infected and symptoms appearing, differs.

The symptoms also differ greatly.

Typhoid symptoms

Typhoid has an incubation period of 3 to 60 days, although usually 8 to 14 days.

Typhoid starts with uncharacteristic symptoms such as a headache, aching limbs and a slightly high temperature. Within 2 to 3 days however, the temperature rises to 39 to 41 degrees.

A clear feeling of malaise then also develops with:

• drowsiness and light-headedness
• abdominal pain
• aching limbs
• sometimes constipation

The high temperature can last for up to three weeks.

The following typical symptoms can also arise:

• diarrhea
• light red, pinhead-sized spots on the stomach
• slowed heartbeat (bradycardia)

Paratyphoid symptoms

Paratyphoid has an incubation period of 1 to 10 days.

Typical symptoms are:

• high temperature of up to 39 degrees
• diarrhea
• nausea and vomiting
• abdominal pain

Typhoid is caused by an infection with Salmonella enterica bacteria. There are two subgroups of these bacteria, which trigger either typhoid or paratyphoid:

• The bacteria in the subgroup Typhi cause typhoid fever, usually simply known as typhoid.
• The bacteria in the subgroup Paratyphi cause typhoid-like diseases, referred to by the collective term paratyphoid.

How is typhoid contracted?

The typhoid pathogens are excreted in the feces and urine of people infected and can therefore get into wastewater. Infection primarily occurs if food that has been contaminated by such wastewater is eaten.

Person-to-person infection is also possible, but very rare.

Typhoid and paratyphoid pathogens are found all over the world. Disease rates are particularly high in countries with poor sanitation, e.g. in Africa, South America and Southeast Asia.

Number of cases in Germany

In Germany, between 50 and 100 cases of typhoid are reported every year.

In 2019, 86 people contracted typhoid and 36 people contracted paratyphoid. Most of these became infected during a trip to Asia, especially to Pakistan or India.

In 2020, the number of typhoid and paratyphoid cases registered in Germany fell by about two thirds compared to the previous year. This was due to the reduced ability to travel during the coronavirus pandemic.

Number of cases worldwide

The World Health Organization (WHO) estimates that 11 to 21 million people around the world develop typhoid every year and that up to 160,000 of these die as a result.

It is estimated that 5.5 million people contract a paratyphoid infection every year.

Typhoid typically has uncharacteristic symptoms in the initial phase followed by a persistently high temperature. These may be followed by complications, some of which are severe.

Patients who have not been treated with antibiotics often take longer to fully recover from the illness.

The illness can break out again following partial recovery. This can happen more than once.

With babies, typhoid is more severe and complications are more common.

Paratyphoid has a similar outlook to typhoid but is less serious.

What are the possible complications of typhoid?

If someone has a severe case of typhoid, life-threatening complications may occur:

• intestinal bleeding and perforation with peritonitis
• gall bladder inflammation
• thromboembolism: blood clots become loose and move to another area of the body where they block a blood vessel and cause an embolism.
• ostitis or osteomyelitis
• endocarditis
• meningitis

The most important measures for preventing typhoid include:

• taking care when consuming food if traveling in high-risk areas
• getting vaccinated against typhoid prior to traveling

Consuming food

Typhoid pathogens are usually transmitted through drinking water. In high-risk areas, tap water and ice made with it for beverages should be avoided if possible.

Uncooked or insufficiently heated food can also be contaminated with typhoid and paratyphoid pathogens. Such food includes green and delicatessen salads, seafood, unpeeled fruit or juices.

Recommended vaccinations

People are strongly advised to get vaccinated before traveling to high-risk areas for typhoid in Asia, South America and Africa – especially if they will be living in basic conditions in the destination country. Travel medics can provide comprehensive information in this regard.

The Standing Committee on Vaccination (STIKO) recommends vaccination for:

• travel to South and Central Asia (e.g. Pakistan, India, Nepal, Afghanistan or Bangladesh) – regardless of travel style
• travel to all areas of Asia, Africa, Central and South America where there are increased cases of illness and low hygiene standards if the travel, living or working conditions there are going to be very basic. This applies if trekking or taking part in relief operations, for example, especially in the event of recent outbreaks and disasters.
• Long-term stays in areas with increased cases of illness, especially where the accommodation is very basic.

Two different vaccines are available: an injection (inactivated vaccine) or oral capsules (live vaccine).

Many health insurance providers cover the cost of travel vaccinations. People with health insurance should ideally contact their provider prior to vaccination to find out the applicable rules.

Injectable vaccine

The injectable vaccine (shot) is also available in combination with a vaccine against hepatitis A.

The injection uses an inactivated vaccine with dead bacteria and is administered into the muscle. It offers immunity for up to three years from the 14th day. The vaccine does not protect against paratyphoid.

Redness and swelling may develop at the injection site plus headaches, aching limbs, feelings of malaise or tiredness are possible.

Oral vaccine

The oral vaccine uses a live vaccine with attenuated bacteria. It is administered in the form of three capsules, with one taken every two days (primary immunization).

The tablets are well tolerated and give about 60 percent of those vaccinated protection for at least one year. The live vaccine also provides partial protection against paratyphoid B.

Possible side effects of the vaccine include:

• nausea and/or vomiting
• stomach pain and headache
• high temperature
• skin rash
• diarrhea that occurs after the high temperature

Revaccination and boosters

People who received the oral vaccine and are once again traveling to a high-risk area are advised to undergo full revaccination after three years.

In the case of permanent residence in a high-risk area, the immunization should be boosted after three years regardless of the vaccine.

Typhoid and paratyphoid infections are often confused with flu infections or, if people have returned from tropical regions, malaria.

Blood count abnormalities can indicate typhoid and paratyphoid, but are not a reliable form of diagnosis.

A reliable diagnosis requires direct detection of the pathogens. To this end, a doctor will take a blood sample that can be used to grow a bacteria culture in a laboratory. In rare cases, bone marrow, urine or feces samples are taken.

The earlier typhoid is treated, the better the chances of recovery. The condition is treated with antibiotics.

The choice of active substance depends on the precise typhoid pathogen, which is determined in a laboratory, especially if people have returned from travels in Asia. Checks are also performed in advance to see if the antibiotic selected actually works.

If you would like to get vaccinated against typhoid or are concerned that you may have typhoid, it’s best to contact a tropical medicine practice.

Some university hospitals have special tropical medicine departments that also offer advice.