Keywords
Cholera
Typhoid fever vaccines
Cholera vaccines
Travel medicine
International travel
Abstract
The burden of diarrheal diseases is very high, accounting for 1.7 to 5 billion cases per year worldwide. Typhoid Fever (TF) and Cholerare potentially life-threatening infectious diseases mainly transmitted through the consumption of food, drink or water that have been contaminated by the feces or urine of subjects excreting the pathogen. TF is mainly caused by Salmonella typhi whereas Cholera is caused by intestinal infection by the toxin-producing bacterium Vibrio cholerae. These diseases typically affect low- and middle-income countries where housing is overcrowded and water and sanitation are poor, or where conflicts or natural disasters have led to the collapse of the water, sanitation and healthcare systems. The mortality rate is higher in children under 5 years. Regarding their geographical distribution, TF has a high incidence in sub-Saharan Africa, India and south-east Asia, while cholera has a high incidence in a few African countries, particularly in the Horn of Africa and the Arabian peninsula.
In the fight against these diseases, preventive measures are fundamental.
With modern air travel, transmissible diseases can spread across continents and oceans in a few days, constituting a threat to global public health. Nowadays, people travel for different reasons such as tourism and business. Several surveys have shown that a high proportion of travellers lack adequate information on safety issues, such as timely vaccination and prophylactic medications. The main objective of this overview is to provide the knowledge for travellers to stay healthy while abroad, and thus also to reduce the potential importation of these diseases and their consequent implications for public health and society.
The preventive measures to be adopted in the case of travel to countries where these diseases are still endemic are well known: the adoption of safe practices and vaccinations.
Vaccination is effective especially when coupled with hand-washing, the treatment of household water, and the provision of adequate sanitation. Furthermore, the emergence of multidrug-resistant strains is becoming a serious problem in the clinical treatment of these diseases. For this reason, vaccination is the main solution.
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