Viral arthritis

Editor – I am grateful to Marks and Marks¹ for their excellent overview of viral arthritis, which provided many useful clinical pointers. Viral arthritis acquired abroad will continue to increase in line with the ever-expanding number of travelers visiting or returning to the UK, especially from tropical climes.² As noted in the review, aetiology of viral arthritis includes alphaviruses such as Chikungunya and also flaviviruses such as Dengue. There is another topical flavivirus that is relevant for the generalist faced with a returned traveler with a fever, rash and arthralgia/arthritis: Zika.

Zika virus has been described as a ‘new global health threat’ for 2016.³ While the majority of those infected with Zika will be asymptomatic, there are major concerns about a possible association between Zika infection in pregnant women and congenital microcephaly.⁴ Twenty one cases of Zika have been diagnosed in the UK since April 2015 in travellers returning from affected countries (predominantly the Americas and the Caribbean).⁵ Returning travellers presenting with a maculopapular rash and/or fever with at least one of the following symptoms (not explained by other medical conditions) meet the World Health Organization criteria of a suspected case: conjunctivitis, arthralgia, or arthritis.⁶ Other symptoms may include itching/pruritus, headache, myalgia, lower back pain, and retro-orbital pain – all of which are compatible with a diagnosis of Dengue fever or Chikungunya.⁵

Public Health England provides comprehensive guidance on Zika virus infection, including a clinical algorithm of investigation of suspected cases and exposed pregnant women.⁵ Management of people with Zika virus infection is supportive, with intravenous fluids if necessary and paracetamol for fever and arthralgia/arthritis. It should be noted that non-steroid anti-inflammatory agents are best avoided until the diagnosis of Dengue has been excluded, because of bleeding risk.

With expanding global travel, emerging and tropical infections are becoming ever more pertinent to and prevalent in day-to-day primary and secondary care practice in the UK. Clinicians should remain vigilant to the 1% of acute arthritis cases of viral aetiology, which include Zika virus infection.