A tourist holidaying with his family in Gozo has imported the sandfly fever virus to Switzerland after he was bitten by the insect, becoming the first person to export the infection, according to a scientific journal.
Higher temperatures are the perfect breeding ground for mosquitoes to propagate
The first report of sandfly fever virus infection imported from Malta into Switzerland was this month registered in Eurosurveillance, a European peer-reviewed online journal.
The journal said this case illustrated the importance of considering sandfly-borne viral infection in the diagnosis of feverish patients from Malta.
“Raising awareness among physicians is relevant especially now at the beginning of the summer tourist season,” it urged.
Sandfly is a blood-sucking insect small enough to get through the tiny holes of a standard mosquito net. It has been around in Malta – especially Gozo – for decades and has mostly plagued dog owners who have helplessly watched their pets suffer from the potentially lethal disease canine leishmaniosis after being bitten.
However, it also targets humans and public health specialist Tanya Melillo envisaged that vector-borne diseases – transmitted to humans by insects – will increase in the coming years.
“Climate change is leading to higher temperatures which are the perfect breeding ground for insects such as mosquitoes to propagate. In future we’re expecting to see more vector-borne diseases,” she said.
Considering the island’s location and climate, Malta like other Mediterranean countries, was at higher risk of infectious diseases transmitted through humans’ bloodstream after being bitten by vectors – that include mosquitoes, fleas, lice, and bugs.
Dr Melillo, head of the Infectious Disease Prevention and Control Unit, said vector-borne diseases were altering mainly due to environmental changes as well as increase in tourism and trade.
Understanding the risk of introduction and spread of such diseases in Europe had become important and a European network on vector-borne diseases had been set up in which Malta participated, she said.
The Swiss case was registered last October when the man in his 40s was hospitalised with fever, nausea, vomiting and an intensifying headache two days after returning from his two-week holiday in Gozo. His wife suffered from similar, but less intense symptoms.
Nine days before his admission, he had suffered from back pain, tiredness and a body temperature that was slightly above normal. However, when he was admitted to hospital he had fever, a generalised rash and a severe headache.
The multiple skin lesions from insect bites and the fact he had been holidaying in the Mediterranean led doctors to test for the sandfly fever virus – it was confirmed.
The man fully recovered 21 days from the onset of the symptoms and the journal reported that eight months later there had been no relapse.
Dr Melillo said cases of visceral (can be fatal if not treated) and cutaneous (affects the skin and is less severe) leishmania have been documented in Malta since at least the 1980s. But no sandfly fever has been recorded and the few requests the unit received over the years to test for it have been sent abroad and returned negative.
Dr Melillo advised that the most effective preventative action was to apply insect repellent with a high concentration of DEET to prevent sandfly bites.
“There is nothing to be alarmed about. Try to avoid being bitten and consult a doctor if you have fever.”