Infectious diseases

Mural in Encarnación, Paraguay: "Let's fight dengue and yellow fever together"

There are many infectious diseases that can pose a hazard to travellers who may not be familiar with them and their risks, because they are rare or absent in their home countries. In particular, vast improvements in sanitation and healthcare standards, combined with the widespread availability of vaccines, have made many once common diseases largely a thing of the past in developed countries. However, these diseases may continue to persist in less developed parts of the world where people do not have access to proper medical care and sanitation, and vaccine coverage is low. This article is a basic introduction to some of these hazards of travel, how to avoid them, and how to deal with one if you contract it. For those unfamiliar with medical jargon, the words infectious and contagious have distinct meanings. An infectious disease is one that is caused by a pathogen, such as a virus, bacterium, fungus or other parasites. A contagious disease is a disease which is easily transmitted by being in the vicinity of an infected person. All contagious diseases, such as influenza and measles, are infectious diseases, but the reverse is not necessarily true, with various diseases such as AIDS or yellow fever being infectious but not contagious.

Before travelling

Legal requirements

Many governments require visitors entering, or residents leaving, their countries to be vaccinated for a range of diseases. These requirements may often depend on what countries a traveller has visited or intends to visit. For example, if you have recently visited hot countries in Africa or Latin America, then other countries may require evidence of yellow fever vaccination before letting you in.

If you are bringing prescription medicine with you, carry a copy of the prescription.

Health requirements

For much travel, especially to tropical or "third world" countries, additional vaccinations or other precautions such as anti-malarial medication may be necessary.

Before starting your travels you should consult a doctor with experience in the field of travel medicine. You should do this at least 8 weeks before you plan to leave, to give time for vaccinations.

Information sources

There are many sources of additional information for travellers:

Disease by transmission method

Pests are not only a nuisance in and of themselves; they can also spread microbe infections to people.

Arthropod vectors

Prevalence of Aedes aegypti, a vector of many (in)famous tropical diseases

Diseases in these categories are typically spread by being bitten by arthropods; a group of small animals including insects such as mosquitos, fleas and flies, as well as others such as mites, ticks and lice. The risk from such diseases can be reduced by using permethrin-treated fabrics and insect repellents when travelling to rural areas.

Lyme disease is prevalent in most of the temperate Northern Hemisphere

Contaminated food and water

Diseases in this category are typically transmitted by ingesting contaminated food or water. Boiling water before you drink it, and ensuring that all food you eat is well cooked are the best precautions against such diseases.

Prevalance of Hepatitis A as of 2005

Sexually transmitted

Diseases in this category (also known as STDs) are typically spread by having unprotected sex with infected persons. However, many of them can also be transmitted by sharing needles, or through contaminated blood transfusions. The best form of protection against such diseases is monogamy, abstinence, or safe sex practices. Sharing of needles should be avoided, and should you need to receive an injection, ensure that all needles used on you are properly sterilized. While these diseases are not spread by casual contact, the reverse is not true--almost all infectious diseases can be transmitted through sexual activity, and for many non-STDs, condoms don't provide protection.

Hep B prevalence map

Airborne transmission

Diseases in this category are extremely contagious, and are typically contracted simply by being in close proximity with an infected individual. There is realistically nothing much you can do to avoid them completely, but you can mitigate the risks by ensuring you have all the necessary vaccinations where available, and avoid travelling to areas where there are epidemics of such diseases if no vaccine is available.


Rabies-free territories

This article is issued from Wikivoyage - version of the Tuesday, March 01, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.