The contribution of travellers visiting friends and relatives to notified infectious diseases in Australia: state-based enhanced surveillance

Abstract

SUMMARYImmigrants and their children who return to their country of origin to visit friends and relatives (VFR) are at increased risk of acquiring infectious diseases compared to other travellers. VFR travel is an important disease control issue, as one quarter of Australia's population are foreign-born and one quarter of departing Australian international travellers are visiting friends and relatives. We conducted a 1-year prospective enhanced surveillance study in New South Wales and Victoria, Australia to determine the contribution of VFR travel to notifiable diseases associated with travel, including typhoid, paratyphoid, measles, hepatitis A, hepatitis E, malaria and chikungunya. Additional data on characteristics of international travel were collected. Recent international travel was reported by 180/222 (81%) enhanced surveillance cases, including all malaria, chikungunya and paratyphoid cases. The majority of cases who acquired infections during travel were immigrant Australians (96, 53%) or their Australian-born children (43, 24%). VFR travel was reported by 117 (65%) travel-associated cases, highest for typhoid (31/32, 97%). Cases of children (aged <18 years) (86%) were more frequently VFR travellers compared to adult travellers (57%, P < 0·001). VFR travel is an important contributor to imported disease in Australia. Communicable disease control strategies targeting these travellers, such as targeted health promotion, are likely to impact importation of these travel-related infections.

Hepatitis E in Long-Term Travelers from the Netherlands to Subtropical and Tropical Countries, 2008–2011

“…In 2 other studies, travelers visiting friends and relatives were found to be at greater risk than tourist travelers for infectious diseases such as typhoid fever ( 6 ) and hepatitis E ( 14 ). Our study showed a higher attack rate (14%) and incidence (5.3 cases/1,000 person-weeks) for travelers visiting friends and relatives than for persons traveling for tourism or work/study, but this association was not strong.…”

Typhoid fever complicated by cholecystitis in a 10‐year‐old boy

“…In a recent review of notifiable diseases in New South Wales and Victoria, children of immigrant families are more likely to acquire infectious diseases overseas compared to adult travellers. Preventative health education for immigrant families is important for disease control in Australia …”

“…Preventative health education for immigrant families is important for disease control in Australia. 4 The presence of gall-bladder stones distracted from considering alternate causes of gall-bladder inflammation, such as systemic infection. The pathogenesis of gallstone cholecystitis is through the obstruction of the cystic duct or by a stone impacted in Hartman's pouch.…”

Travellers visiting friends and relatives: a high‐risk, under‐recognised group for imported infectious diseases

“…Additionally, VFR travellers may not have completed childhood vaccinations if born overseas, and are less likely to have sought pre‐travel advice, have travel health insurance or adhere to malaria chemoprophylaxis . Moreover, partial immunity acquired while residing in their country of origin to certain gastrointestinal pathogens, typhoid and malaria, will wane over time and VFR travellers may not be aware of this waning immunity.…”