The GSA Blog

Travelling schistosomiasis - new risks for tourists


For many who live outside of the tropics, schistosomiasis and the other neglected tropical diseases (NTDs) seem like a distant problem. Indeed, schistosomiasis is most devastating for populations in the so-called developing world, with at least 90 per cent of the estimated 249 million infected people residing in Africa.[1] However, with the rise in international travel and eco-tourism in “off the beaten track” destinations, the at-risk community is broadening and new patterns of disease transmission and dissemination are emerging.

In the state of Minas Gerais in Brazil, the development of eco-tourism may have led to two major outbreaks of schistosomiasis among non-residents over the past few years. The visitors, who had mainly travelled to the rural tourism destination from urban centres, came into contact with infected fresh water in rivers and lakes during recreational eco-tourism activities.[2] A study by Brazilian scientists into the Minas Gerais cases stressed that the severity of the disease differed significantly between locals and tourists; tourists experience clinically more severe symptoms as the “immune response to the parasite is different from that of residents in endemic areas”.[3] These cases are among a number of recent incidents of acute schistosomiasis connected to rural tourism, confirming a new pattern of schistosomiasis infection and contributing to the spread of the disease among new demographics and into non-endemic areas.[4]

Another popular tourist attraction that is increasingly being associated with schistosomiasis infections is white-water rafting in Sub-Saharan Africa. Independent research teams that studied tourists who had recently been rafting in Ethiopia[5] and Uganda[6], were both able to diagnose a large number of screened individuals with schistosomiasis. The most famous patient of schistosomiasis following a rafting trip is most certainly HRH Prince William, who contracted the disease in 2003 when he went white-water rafting on the Nile.[7] The perception that white-water rafting is not dangerous due to the fast-flowing water therefore does not hold. It may be that when rafts and kayaks are pulled in and out of the water that individuals are at highest risk of infection. Given the large number of people who decide to go rafting on their African holidays, booking agencies should make such travellers aware of the risks.

While schistosomiasis is typically associated with poverty (poor living conditions, inadequate sanitation and lack of clean water), in recent years there have been unprecedented cases of locally-acquired schistosomiasis in the popular European holiday destination of Corsica, France. Between 2011 and 2013, 11 people from France and Germany became infected with schistosomiasis after being exposed to freshwater in a natural swimming area, the Cavu River, in Southern Corsica.[8] It is believed that schistosomiasis was introduced to the river by infected people arriving from an endemic region.

Many travellers to endemic countries may become infected with schistosomiasis but remain undiagnosed if they experience only mild symptoms over an extended period of time, or if their symptoms are confused with those of other conditions. Many people who pick up the disease even remain asymptomatic. The Hospital for Tropical Diseases in London offers post-tropical screening to travellers who are well but who may have been exposed to a tropical condition such as schistosomiasis whilst abroad, as well as an emergency walk in clinic for those who are acutely unwell and presenting symptoms.[9]

Tourists should be aware that there may be something in the water – something many people may not even know exists – especially in countries where schistosomiasis is endemic but also in locations where you may least expect it. As travellers venture to more rural and “off the beaten track” locations, schistosomiasis infects new demographics and even spreads, transported by those contaminated with the disease, to non-endemic regions of the world. Watch the ‘Something in the Water’ video here to learn more.

 


[1] http://www.who.int/mediacentre/factsheets/fs115/en/

[2] http://www.ibtimes.co.uk/parasitic-worms-burrow-through-your-skin-schistosomiasis-driven-by-brazils-eco-tourism-1545704

[3] http://download.springer.com/static/pdf/235/art%253A10.1186%252Fs40794-016-0019-8.pdf?originUrl=http%3A%2F%2Ftdtmvjournal.biomedcentral.com%2Farticle%2F10.1186%2Fs40794-016-0019-8&token2=exp=1457375560~acl=%2Fstatic%2Fpdf%2F235%2Fart%25253A10.1186%25252Fs40794-016-0019-8.pdf*~hmac=1f0039c69574aa11a310dc4e28749f3651024f411aba0b9ae95f97779856002e

[4] http://www.ncbi.nlm.nih.gov/pubmed/20721505

[5] https://www.researchgate.net/profile/Martin_Cetron/publication/7748699_Schistosome_infection_among_river_rafters_on_Omo_River_Ethiopia/links/540edff20cf2d8daaaceaa74.pdf

[6] http://wwwnc.cdc.gov/eid/article/16/5/09-1740_article

[7] http://www.telegraph.co.uk/news/health/expat-health/4190509/The-worm-turns.html

 

[8] http://www.thelancet.com/journals/laninf/article/PIIS1473-3099(15)00084-5/abstract

[9] http://www.thehtd.org/screening.aspx

Reaffirming our commitment to elimination


 

We were delighted to hold the first meeting of programme managers from high-burden schistosomiasis countries organised by the GSA’s Implementation Working Group, late last year in Benin.

Representatives from high-burden countries, Nigeria, Ethiopia, Tanzania (mainland) and Mozambique were joined by country managers from those countries with mature schistosomiasis programmes –Malawi and Zanzibar.

The meeting was designed to help country programme managers develop and review schistosomiasis-control implementation plans and to discuss the availability of resources needed to deliver the donations of Praziquantel readily available to communities in need.

Having representatives from Malawi and Zanzibar, countries which have seen great strides in the control of schistosomiasis through preventative chemotherapy programmes, allowed us to share relevant experience and best practice – demonstrating that with the right approach, schistosomiasis can be controlled and – eventually – eliminated.

The meeting also allowed country programme managers to specify their expectations of the Global Schistosomiasis Alliance and what they want the GSA to do and focus on in the future, to help them garner financial and political commitment to fight schistosomiasis on a larger scale.

It was agreed that the GSA should focus on a range of actions in 2016, including:

Increased engagement with the soil-transmitted helminth community – control and treatment of schistosomiasis and STH go hand in hand. The GSA should continue to work closely with the STH coalition to support reaching the 2020 NTD road map target to at least 75% regular treatment with anthelminthics.

Ongoing co-ordination with the World Health Organization – the GSA will continue to work in partnership with the NTD teams at WHO Headquarters, AFRO and country offices to support efforts to achieve two key WHA resolutions on the elimination of schistosomiasis (WHA 65.21) and on NTDs (WHA 66.12)

Country support on treatment approaches – the GSA will support countries with treatment approaches required to reach elimination, including technical support to identify transmission hotspots.

Coordination of Praziquantel donations – the GSA will bring all Praziquantel donors and procurement agencies together to encourage better coordination. In particular, to help countries understand what drugs they will receive from which partner and when and how to co-ordinate drugs from more than one source in a single country.

The meeting in Benin saw us reaffirm our commitment to elimination and we are excited about the potential the GSA has to make meaningful strides towards elimination.

To read the full report from the meeting in Benin, please see here: 

http://eliminateschisto.org/repository/media/1456926488-56d6ef1883bca-965742.pdf