Research and analysis

HPR volume 12 issue 29: news (10 and 13 August)

Updated 21 December 2018

Cyclospora in travellers returning from Mexico

An increase in cases of Cyclospora cayetanensis infection in travellers who have recently returned from Mexico is being investigated by Public Health England, Public Health Wales, Health Protection Scotland and the Health Protection Service Northern Ireland. This is the fourth successive year since 2015 that cases of C. cayetanensis infection have been reported in travellers returning from Mexico [1-4].

As of 10 August 2018, 63 laboratory-confirmed cases of C. cayetanensis have been reported in England, Scotland and Wales. Where information is available, 55 (87%) report travel outside the UK. Of these, 49 (89%) report recent travel to Mexico. Where information is available, cases have stayed at several different hotels in the Cancun and Riviera Maya region (mostly on an all-inclusive basis), suggesting the source is likely to be a foodstuff that has been distributed to hotels throughout the region.

C. cayetanensis is a protozoan parasite that infects humans and other primates. Infection can cause diarrhoea, abdominal cramping, nausea, flatulence, loss of appetite, fatigue, low-grade fever and weight loss. Infection without symptoms is also reported. Infections in HIV positive people and those with other immune deficiencies can be more severe.

Infection is commonly derived from food or water contaminated by human faeces. There is no evidence of transmission from animals. Oocysts (a hardy form in the lifecycle of this parasite) are not infectious for around 10 days after they are passed in faeces, so person-to-person transmission does not occur.

The foods commonly involved are soft fruits such as raspberries and salad products such as coriander, basil, and lettuce.

C. cayetanensis is a common infection in the tropics and the vast majority of cases reported in the UK are associated with travel to these areas. The risk of infection presented by imported foods is considered to be low [5].

Advice for travellers

Advice on prevention of cyclosporiasis is available on the NaTHNaC and PHE websites.

References

1. Nichols GL, Freedman J, Pollock KG, Rumble C, Chalmers RM, Chiodini P, and others (2015). Cyclospora infection linked to travel to Mexico, June to September 2015. Euro Surveill 20(43).
2. PHE (2016). Cyclospora:clinical and travel guidance.
3. PHE (2017). Cyclospora outbreak related to travel to Mexico (2017)”. HPR 11(26).
4. European Centre for Disease Prevention and Control (2017). Rapid risk assessment: Cyclospora infections in European travellers returning from Mexico.
5. Chalmers RM, Nichols G, Rooney R (2000). Foodborne outbreaks of cyclosporiasis have arisen in North America. Is the United Kingdom at risk?. Commun Dis Public Health. 3(1): 50 to 55.

VZIG supply shortage: an update

As of 8 August 2018, following a further review of the current supply situation, and of the evidence of efficacy and safety of antivirals for post-exposure prophylaxis, updated guidance on the use of VZIG, issued in July [1], has been strengthened.

Use of VZIG is now restricted to susceptible women exposed in the first 20 weeks of pregnancy and neonates. Antiviral agents are recommended for post-exposure prophylaxis for pregnant women exposed after 20 weeks, and for immuno-suppressed individuals [2].

References

1. “Updated guidance on use of Varicella Zoster Immunoglobulin (VZIG) during supply shortage”. HPR 11(25), 13 July.
2. PHE (August 2018). Updated restrictions on use of Varicella Zoster Immunoglobulin (VZIG) during supply shortage: advice to health professionals.

Infection reports in this issue of HPR

Zoonoses

Common animal associated infections quarterly report (England and Wales): second quarter 2018

GI infections

Routine reports of foodborne illness in humans, England and Wales: weeks 27 to 30, 2018.

Suspected and laboratory confirmed reported norovirus outbreaks in hospitals: outbreaks occurring in weeks 27 to 30, 2018.