Neurocysticercosis and new-onset seizures in short term travellers to Bali

Case Report: Neurocysticercosis Acquired in Australia

Neurocysticercosis (NCC) is a disease caused by infection of the central nervous system with the larval stage of the tapeworm Taenia solium. This disease is endemic in many parts of the world, including Africa, Asia, and Latin America, where animal husbandry practices are common such that pigs reared for human consumption ingest feces from humans infected with T. solium. Neurocysticercosis is rarely acquired in economically affluent regions, including North America, Central Europe, Japan, and Australasia, and in countries where pork consumption is discouraged by religious or social practices. In these countries, NCC is usually diagnosed in immigrants or returning travelers who have spent time in endemic regions. Here, we report a case of NCC in a 25-year-old woman presenting with worsening visual symptoms in association with headache, diagnosed previously as a migraine with visual aura. This person had always lived in Australia and had never traveled overseas to a country endemic for T. solium. The unusual features of the clinical presentation and epidemiology are highlighted to raise physicians' awareness that attention needs to be paid to the risk of autochthonous infection occurring in non-endemic countries.

Neurocysticercosis among international travelers to disease-endemic areas

OBJECTIVE

Review of neurocysticercosis in citizens from non-endemic countries who developed the disease after a travel to endemic regions, to estimate the magnitude of the disease and to determine the pattern of disease expression in travelers to disease-endemic areas.

METHODS

MEDLINE and manual search of international travelers with neurocysticercosis diagnosed in countries where the disease is not endemic, from 1981 to October 2011. Abstracted data included: demographic profile of patients, clinical manifestations, form of neurocysticercosis, and therapy.

RESULTS

A total of 35 articles reporting 52 patients were found. Most patients were originally from Western Europe, Australia, Israel, and Japan. Mean age was 36.5 ± 15.1 years, and 46% were women. Common places for travelling were the Indian Subcontinent, Latin America, and Southeast Asia. Mean time spent aboard was 56.6 ± 56.1 months. Most patients developed symptoms 2 years or more after returning home. Seizures were the most common clinical manifestation of the disease (73%), and all but six patients had parenchymal brain cysticercosis (a single cysticercus granuloma was the most common neuroimaging finding, in 21 patients). Twenty patients underwent surgical resection of the brain lesion for diagnostic purposes, and 22 received cysticidal drugs.

CONCLUSIONS

Neurocysticercosis is rare in international travelers to endemic countries, and most often occurs in long-term travelers. It is possible that most of these patients get infected by contact with a taenia carrier. The time elapsed between disease acquisition and symptoms occurrence suggests that, at least in some patients, clinical manifestations are related to reactivation of an infection that has previously been controlled by the host immune system.

Neurocysticercosis in travelers: a nation-wide study in Israel

BACKGROUND

Cysticercosis, a human infestation by Taenia solium is endemic in many resource-limited countries. In developed countries it is mostly encountered among immigrant populations. Only few cases are reported in travelers. This report summarizes a nation-wide study of neurocysticercosis (NCC) diagnosed among Israeli travelers to endemic countries, with an estimation of disease incidence among the traveler population.

METHODS

We performed a retrospective, nation-wide survey of travel-related NCC in Israel between the years 1994 and 2009.

RESULTS

Nine cases of NCC were diagnosed in Israeli travelers during the study years. Most patients had traveled to South and/or Southeast Asia. The most common symptom at diagnosis was a seizure. The average interval between return from the suspected travel and symptom onset was 3.2 ± 1.8 years. Two patients suffered from multiple lesions, whereas the rest had a single lesion. Antihelminthic treatment was given to most patients with resolution of symptoms. Median duration of antiepileptic treatment was 16 ± 41 months after albendazole was given. Antiepileptic treatment was discontinued without any complications. The estimated attack rate of clinical disease was 1 : 275,000 per travel episode to an endemic region.

CONCLUSIONS

NCC in travelers is a rare phenomenon commonly presenting as seizure disorder manifesting months to years post-travel. Antihelminthic therapy followed by 12 to 24 months of antiepileptic therapy resulted in complete resolution of symptoms in our patients.

Parasitic worms of the central nervous system: an Australian perspective

The diagnosis and management of parasitic diseases of the central nervous system (CNS) is difficult, even for infectious diseases physicians and neurologists. Furthermore, few overviews of the spectrum of causative helminths and clinical syndromes have been published. In the present study, we review the seven most common parasitic diseases of the CNS: (i) cysticercosis, (ii) neuroschistosomiasis, (iii) paragonimiasis, (iv) angiostrongyliasis, (v) hydatid disease, (vi) sparganosis and (vii) gnathostomiasis. Major syndromes of parasitic disease of the CNS and their differential causes are discussed, including: (i) cystic lesions, (ii) enhancing granulomas (with and without creeping subcutaneous eruptions), (iii) eosinophilic meningoencephalitis and (iv) spinal cord disease. Specific risk factors that predispose to these infections are also discussed and particular attention is drawn to the situation in Australia.

Eradication of Taenia solium cysticercosis: a role for vaccination of pigs

Neurocysticercosis due to Taenia solium is an important cause of human morbidity and mortality, particularly in Latin America and parts of Africa and Asia. The disease has been recognised as potentially eradicable. Emphasis has been placed on control of the parasite through mass chemotherapy of human populations to remove tapeworm carriers. This strategy does not control the source of tapeworm infections, cysticercosis in pigs, and parasite transmission may continue due to incomplete chemotherapy coverage of human tapeworm carriers or because of immigration of tapeworm carriers into control areas. Exceptionally effective, practical vaccines have been developed against cysticercosis in sheep and cattle and a recent trial has proved recombinant antigens to be effective against Taenia solium cysticercosis in pigs. A new strategy for eradication of Taenia solium is proposed, based principally on a combined approach of chemotherapy of human tapeworm carriers and vaccination of all pigs at risk of infection.

Travel and Health Research in Australia

Travel and tourism is a major industry in Australia, employing 6.9% of the nation's workforce (535,600 persons) and generating AUS$46.9 billion in 1993-94.1 While economic and marketing analyses have traditionally dominated the field of tourism research in Australia, health and safety issues that impact on the business of tourism are now emerging.2 Travel medicine is still a small specialty area, though it has established a legitimate role within the tourism industry by providing services in prevention and treatment. To date, little attention has been given to empirical research, even though field studies are a critical component in the provision of accurate medical advice for patients. This paper reviews the Australian research that is available and identifies areas where further work should be conducted.