Vaccine-preventable diseases and their prophylaxis.

Global uptake of new vaccines shapes the epidemiology of infections, and in turn this changing epidemiology guides vaccine development. Once introduced, surveillance and monitoring of the impact of vaccines on disease and adverse events is vital for further development. This article reviews the use of vaccines as part of routine health care, vaccines that may be required for entry into a destination country, and vaccines that are recommended because of risk during travel. Considerations and advances in the vaccination of travelers are addressed.

Gnathostomiasis, another emerging imported disease.

Gnathostomiasis is a food-borne zoonosis caused by the late-third stage larvae of Gnathostoma spp. It is being seen with increasing frequency in countries where it is not endemic and should be regarded as another emerging imported disease. Previously, its foci of endemicity have been confined to Southeast Asia and Central and South America, but its geographical boundaries appear to be increasing, with recent reports of infection in tourists returning from southern Africa. It has a complex life cycle involving at least two intermediate hosts, with humans being accidental hosts in which the larvae cannot reach sexual maturity. The main risks for acquisition are consumption of raw or undercooked freshwater fish and geographical exposure. Infection results in initial nonspecific symptoms followed by cutaneous and/or visceral larva migrans, with the latter carrying high morbidity and mortality rates if there is central nervous system involvement. We review the literature and describe the epidemiology, life cycle, clinical features, diagnosis, treatment, and prevention of gnathostomiasis.

Gnathostomiasis acquired by British tourists in Botswana.

Infection with Gnathostoma spinigerum has been generally confined to Southeast Asia and Central and South America. However, gnathostomiasis was recently found in British tourists who had visited Botswana. Consequently, travel to Africa should now be considered a risk factor for gnathostomiasis.