Disease pattern

Typhoid abdominalis can occur worldwide. In Germany, this disease has been greatly reduced by epidemic hygiene measures, but here, too, flare-ups of disease must always be expected. The main source of this danger is the introduction of typhoid fever by travelers.

Epidemiology

The causative agent of abdominal typhus occurs worldwide. More than 43 million cases are reported each year, including about 200 in Germany. However, the number of unreported cases is likely to be high. Depending on the hygienic conditions, the risk of infection varies in individual countries. It is largest in North and Central Africa and in Mexico. In principle, all warm countries are particularly affected. More and more cases of typhoid fever are being imported into Germany from these regions.
For the traveler, the degree of risk depends on the hygiene standard of the trip. Club trips and stays in international hotels are less dangerous. Trekking travelers are more likely to be affected. Even careful behavior cannot completely eliminate the risk of infection. You don’t usually see behind the kitchen doors of restaurants.

Pathogen and infection

Salmonella typhi is a gram-negative rod with peritrichous flagella. Infections are almost exclusively oral. Sources include direct or indirect person-to-person contagions, contact with sick persons and permanent excretors. Particular sources of danger are drinking water contaminated by typhoid feces, milk, meat and other foodstuffs, e.g. potato salad. If stored improperly, the pathogens multiply massively. Boiling kills the germs. Thus, the danger comes mainly from raw, uncooked food, especially if it has been stored for a long time.
The duration of contagiousness varies. It remains in place until the stool and urine are completely free of germs.
Permanent excretors, who may spread the disease for years, are a particular danger. 5% of those who are ill or infected become permanent excretors and thus sources of infection for others. In Germany, about 1,700 permanent excretors are registered annually. The disease is notifiable in our country. All reported will be inspected by the health department. Activities in the food area are prohibited during the period of excretion. Thus, for special occupational groups, the contagion even threatens the existence in some cases.

Disease pattern

The incubation period is 3 to 60 days, usually 10 to 14 days. Susceptibility to the disease depends on general condition and exposure, but gastric acidity also plays an important role, so extreme gluttony should be avoided. The number of ingested Salmonella seems to be one of the decisive factors for the outbreak of the disease, therefore the freshness of the food preparation is a safety factor.
Unlike other types of salmonella, the typhoid pathogen overcomes the intestinal barrier so that the infection affects the whole body. The onset of the disease is uncharacteristic with dullness, headache and slow “staircase” rise of fever. After the prodromes lasting about a week, the so-called continua sets in with temperatures around 40°C for one to two weeks. There is a strong influence on the sensorium. Typical is the gray-yellow covered “typhoid tongue”. Other signs include relative bradycardia, leukopenia (2,000 to 4,000), and left shift. Roseolae form on the abdominal skin from the 10th day of illness. There is swelling of the spleen, pea porridge-like diarrhea, hair loss, bedsores. If the course is free of complications, a gradual fever remission sets in during the 4th week after morning fever remission. The convalescence is long lasting. Complications may include toxic circulatory failure, intestinal hemorrhage, intestinal ulceration, with possible intestinal perforation, peritonitis, pneumonia, myocarditis, splenic rupture, thrombosis, meningoencephalitis, cholangitis, cholecystitis, and osteomyelitis. Thus, the disease must be classified as quite life-threatening. Of course, adventure travelers without appropriate medical care options are particularly at risk.
Typhoid fever is thus, especially in the early stages, not so much a disease of the intestine but of the whole organism.

Laboratory diagnosis

Diagnostic confirmation of typhoid disease is done by blood culture during the first two weeks of illness. From the end of the second week by bacteriological examination of stool, bile and urine.
Preliminary serologic testing can be performed after 24 to 48 hours with slide agglutination. The final result can be determined after 3 days at the earliest. Detection with the Gruber-Widal agglutination assay can be performed towards the end of the first week of illness at the earliest. The rise in titer supports the diagnosis.

Therapy

Treatment is with fluid and electrolyte replacement, as well as high-calorie nutrition and general nursing measures. Glucocorticosteroids are used in toxic courses. Cefotaxime and cotrimoxazole are used on a pathogen-specific basis. Treatment options are relatively good with early initiation of therapy. Toxic damage that has already occurred is usually no longer reversible. Thus, about 20% of those with the disease die, often because the diagnosis is made too late.
The treatment always has to be done as an inpatient, which is a problem for the tourist in many travel countries. This is another reason why prevention is of crucial importance.

Prophylaxis

The most important protection is adapted behavior. If possible, only boiled and cooked dishes should be eaten in the regions at risk. Beverages must be boiled or originally packaged. Ice cubes may also contain reproductive pathogens.

The typhoid vaccination & vaccination indication

Typhoid vaccination should be given whenever there is a comparably higher risk to the traveler from this disease.
To give the indication for typhoid vaccination depends on

  • From the destination: tropical or subtropical regions; regions with low hygiene standards; endemic or epidemic areas
  • From the way of traveling
  • Business travelers: These are often particularly at risk, as they cannot pick out the venues themselves when they receive invitations.
  • Trekking travelers in poor hygiene conditions
  • Adventure trips with visits to low category hotels or inns
  • longer-term stays at work in warm countries (G35 of the guidelines of the employers’ liability insurance association).
  • Vaccination is particularly important for children, as they are usually not very careful about hygiene and often put everything in their mouths.

The indication is only relative for package tours in good hotels or club resorts without an intensive visit to the country. This is equally true for ship voyages. Mountaineers and other travelers who are exclusively self-sufficient are hardly at risk if they observe the elementary basic rules of food hygiene.In principle, the indication should be rather generous given the good tolerance of this vaccination. In our vaccination practice, we always try to alternate both vaccines to achieve a higher protection factor for the typhoid vaccine.

Vaccine

Two highly effective and well-tolerated vaccines are currently licensed in Germany:

  • The oral typhoid vaccine: Here, a total of three tablets are taken, each two days apart. The cold chain must be observed. The capsules must be swallowed whole, which may limit their use in young children. Side effects are rare, even in our own experience, and are usually limited to mild gastrointestinal disturbances on the days the drug is taken. The duration of protection for travelers is 1 year, and up to three years for stays in endemic areas. Simultaneous use with mefloquine or antibiotics inhibits efficacy. Maintaining the cold chain is important. According to the regulations, the capsules must be swallowed whole, which sometimes causes difficulties.
  • The parenteral vaccine: This is applied as a single dose i.m. or s.c.. Its term of protection is three years. It is approved for children from 2 years. Side effects are exceptionally rare and are usually limited to mild irritation at the injection site. Parenteral vaccination is especially important for children who often have trouble swallowing large tablets. For both vaccines, there are no intervals to observe with other vaccinations. The recommendations on the respective instructions for use apply.

Both vaccines protect against the serious illness of typhoid abdominalis. They cannot prevent petty diarrheal diseases. Thus, eating and drinking hygiene must be observed despite vaccination.