Travelvax Australia, the Australian arm of specialist travel medicine service Travelvax, has issued a bulletin aiming to soothe Australian tourists’ concerns about the recent outbreak of West Nile virus (WNV) in the US. The virus, cases of which have increased from 25 in July to 1,118 in August (with 41 deaths at the time of writing), is circulating in 47 of the 51 US states, with around 75 per cent of cases being reported in Texas, Mississippi, Louisiana, South Dakota and Oklahoma. It is unlikely to peak until the end of September, and there is no vaccine or specific treatment, so naturally tourists will be wary and possibly reluctant to travel, but Travelvax assures travellers that the risks posed to them by the disease are generally low.
The company says that the 1,118 reported instances of WNV probably represent a very small proportion of the actual number of cases because the majority have gone unreported – largely because 80 per cent of cases are symptomless, so many people will not even be aware that they have the disease. Although around half of the reported cases have been described as ‘neuroinvasive’ (i.e. leading to further complications and conditions such as meningitis), overall only one in 150 people will experience anything serious enough to necessitate a trip to hospital.
WNV is transmitted by mosquitoes, which tend to bite during the day, so travellers are advised to take precautions – such as using personal insect repellent – to avoid them. Symptoms, if they appear, tend to manifest three to six days after infection, although it can take as long as 12. Over-50s tend to be more at risk than younger people.