Hepatitis A occurs all over the world, but the risk of infection is higher in countries with poor hygiene standards. There is an increased risk in most tropical and subtropical countries, as well as in some countries in Eastern Europe and around the Mediterranean.
In recent years, there have also been increasing cases in North America and Europe, including Switzerland, especially among men who have sex with men (MSM). Outbreaks in northern European countries can also occur when unvaccinated children become infected during family visits to tropical and subtropical countries. Upon return, they may transmit the virus within their care facilities.
There is a safe and very effective vaccine that consists of two injections at least 6 months apart. It provides lifelong protection after the second dose. Hepatitis A vaccination can also be given in combination with hepatitis B vaccination (3 doses required).
Vaccination against hepatitis A is recommended for all travellers to risk areas, as well as for persons at increased personal risk: persons with chronic liver disease, men who have sex with men, people who use or inject drug, persons with increased occupational contact with persons from high-risk areas or populations, and others.
All travellers should have completed a basic immunisation and boosters according to the Swiss vaccination schedule, LINK.
Travellers should be immune to chickenpox. Persons between 11 and 40 years of age who have not had chickenpox should be vaccinated (2 doses with minimum interval of 4-6 weeks).
“Cook it, boil it, peel it or forget it” – this simple slogan would be sufficient to prevent typhoid fever nearly entirely. However, only few travelers fully adhere to this advice. Nevertheless, the value of food and water hygiene cannot be stressed enough: avoid buying water bottles without proper sealing, avoid drinking tap water from unknown sources, avoid eating cooled / frozen foods (i.e. ice cubes in water or ice cream) and avoid eating raw fruits and vegetables that you yourself have not peeled and washed with clean drinking water.
Two types of vaccines are available:
Dengue fever is the most common insect-borne infectious disease worldwide. There are 4 known serotypes of dengue virus, so it is possible to be infected with dengue more than once. Approximately 1 in 4 infected individuals develop symptoms of dengue, resulting in high fever, muscle and joint pain, and skin rash. In rare cases, most often after a second infection, life-threatening bleeding and shock (severe drop of blood pressure) may occur.
In 3 out of 4 cases, an infection with the virus remains asymptomatic. After a short incubation period (5-8 days), 1 out of 4 infected people present an abrupt onset of fever, headache, joint, limb and muscle pain, as well as nausea and vomiting. Eye movement pain is also typical. A rash usually appears on the 3rd or 4th day of illness. After 4 to 7 days, the fever finally subsides but fatigue may persist for several days or weeks.
In rare cases, severe dengue can occur. Particularly susceptible are local children and seniors as well as people who have experienced a prior dengue infection. Tourists extremely rarely present with severe dengue. In the first days, the disease resembles the course of classic dengue fever, but on the 4th/5th day, and usually after the fever has subsided, the condition worsens. Blood pressure drops, and patients complain of shortness of breath, abdominal discomfort, nosebleeds, and mild skin or mucosal hemorrhages. In the most severe cases, life-threatening shock may occur.
There is no specific treatment for dengue virus infection. Treatment is limited to mitigation and monitoring of symptoms: fever reduction, relief of eye, back, muscle and joint pain, and monitoring of blood clotting and blood volume. Patients with severe symptoms must be hospitalised.
For treatment of fever or pain, paracetamol or acetaminophen are recommended (e.g. Acetalgin® Dafalgan®). Drugs containing the active ingredient acetylsalicylic acid (e.g. Aspirin®, Alcacyl®, Aspégic®) must be avoided.
Effective mosquito protection during the day and especially during twilight hours (i.e. sunset) is the best preventive measure:
No vaccination against dengue virus is currently available for travellers.
The infection may present with some or all of the following symptoms: sudden onset of high-grade fever, chills, headache, redness of eyes, muscle and joint pain, and rash. The rash usually occurs after the onset of fever and typically involves the trunk and extremities, but can also include the palms, soles of the feet, and the face.
Often fever occurs in two phases of up to one week duration, with an interval of one to two fever-free days in between. The second phase may present with much more intense muscle and joint pain, which can be severe and debilitating. These symptoms are typically bilateral and symmetric and mainly involve hands and feet, but may also involve the larger joints, such as the knees or shoulders.
About 5-10% of infected people continue to experience severe joint pain even after the fever has subsided, in some cases lasting up to several months or, albeit rare, even years.
The Zika virus was identified in 1947 in monkeys from the Zika forest in Uganda. Virus circulation has long been limited (a few cases each year) in Africa and South-East Asia. In May 2015, the American continent was affected for the first time, with an epidemic in Brazil that rapidly spread to South America, Central America, and the Caribbean. Since then, the disease has been reported in most tropical and subtropical regions.
The risk of infection is currently low in most regions and does not require specific measures. However, epidemics may occasionally reappear. During epidemics, the risk of transmission is high, and specific recommendations for the traveller are necessary.
In case of fever, it is recommended to consult a doctor. The symptoms of a Zika virus infection may seem similar to those of malaria, for which urgent treatment is necessary, or dengue fever. Treatment for Zika aims for reduction of fever and joint pain (paracetamol). Avoid aspirin and anti-inflammatory drugs (e.g. ibuprofen) as long as dengue fever is not excluded. There is no vaccine available.
In case of pregnancy and fever during or upon return from a Zika virus transmission area, blood and/or urine tests are indicated. In case of confirmed infection, the medical management should be discussed with the gynecologist and infectious/travel medicine specialists.
The risk of infection can be reduced by effective protection from mosquito bites during the day and in the early evening (long clothing, mosquito repellents, mosquito net).
When travelling in an area of increased risk (= declared epidemic) and in order to prevent possible sexual transmission of the virus, it is recommended to use a condom / Femidom during the trip and at least 2 months after return.
Due to the risk of fetal malformation, pregnant women are advised against travelling to areas at increased risk (= declared as epidemic) of Zika transmission at any time during pregnancy (in case of essential travel, a consultation with a travel medicine specialist is advised before departure). Women who wish to become pregnant should wait at least 2 months after their return (or that of their partner) from an area at increased risk of Zika transmission.
Wichtig: Eine STI kann auch ohne oder mit nur leichten Symptomen auftreten. Auch wenn Sie sich dessen nicht bewusst sind, können Sie andere anstecken. Deshalb ist es wichtig sich testen zu lassen.
Durch Bakterien oder Parasiten hervorgerufen
Alle diese Krankheiten können geheilt werden. Wichtig ist dabei, frühzeitig zu testen und umgehend zu therapieren, um Komplikationen und v.a. weitere Übertragungen zu vermeiden.
Durch Viren hervorgerufen
There is a risk of arthropod-borne diseases other than malaria, dengue, chikungunya or zika in sub-/tropical regions, and some areas of Southern Europe. These include the following diseases [and their vectors]: