ID News: August 2016

Volume 42-8, August 4, 2016: Current travel risks

ID News

2016 Summer Olympic and Paralympic Games in Rio de Janeiro, Brazil

Source: Government of Canada. Travel Health Notices 2016 Summer Olympic and Paralympic Games in Rio de Janeiro, Brazil Updated: June 14, 2016.

Level 2: Practise special precautions: The 2016 Summer Olympic and Paralympic Games will be hosted in Rio de Janeiro, Brazil from August 5 to August 21 and September 7 to September 18 respectively. Due to the ongoing outbreak of Zika virus infection in Brazil, the Public Health Agency of Canada recommends that travellers practise special precautions to help ensure a healthy trip when attending the 2016 Summer Olympic and Paralympic Games. Experts now agree that the Zika virus infection is a cause of microcephaly (abnormally small head) in newborns and of Guillian-Barre Syndrome (a neurological disorder).The Agency recommends that pregnant women and those planning a pregnancy should avoid travel to the Olympics. All travellers should protect themselves from mosquito bites.

Before your trip:

Consult a health care provider or visit a travel health clinic, preferably six weeks before you travel.

• Review travel health recommendations for Brazil
• Get vaccinated
• Purchase travel health insurance
• Pack a travel health kit
• Register with ROCA (Registration of Canadians Abroad)

Special precautions for Zika virus:

• Pregnant women and those planning a pregnancy should avoid travel to the Olympics.
• Travellers should protect themselves from mosquito bites at all times, as the Zika virus is transmitted by a mosquito that can bite in daylight and evening hours. These mosquitoes generally do not live or transmit disease at elevations above 2,000 meters. A list of how to prevent insect bites is available on the Government of Canada's website.
• Most people who have Zika virus illness will have mild symptoms that resolve with simple supportive care. If you are pregnant, or you have underlying medical conditions, or you develop more serious symptoms that could be consistent with Zika virus infection, you should see a health care provider and tell them where you have been travelling or living.

During your trip:

• Practise safe food and water precautions
• Practise insect bite prevention
• Protect yourself from animal-related diseases (e.g., rabies)
• Protect yourself from HIV/AIDS and other sexually transmitted infections (STIs)
• Be alert to crime
• Pay attention to the weather (e.g., stay hydrated)
• Drive with caution: The leading cause of death among international travellers is traffic accidents.
• If you feel sick during your trip:
  • See a health care provider if you feel very unwell, especially if you have a fever.

After your trip:

• If you are sick after you return, see a health care provider and tell them where you have travelled and if you are pregnant.

The risk of dengue for non-immune foreign visitors to the 2016 summer olympic games in Rio de Janeiro, Brazil

Source: Ximenes R, Amaku M, Lopez LF, Coutinho FA, Burattini MN, Greenhalgh D, Wilder-Smith A, Struchiner CJ, Massad E. The risk of dengue for non-immune foreign visitors to the 2016 summer olympic games in Rio de Janeiro, Brazil. BMC Infect Dis. 2016 Apr 29;16(1):186. doi: 10.1186/s12879-016-1517-z.

Background: Rio de Janeiro in Brazil will host the Summer Olympic Games in 2016. About 400,000 non-immune foreign tourists are expected to attend the games. As Brazil is the country with the highest number of dengue cases worldwide, concern about the risk of dengue for travelers is justified.

Methods: A mathematical model to calculate the risk of developing dengue for foreign tourists attending the Olympic Games in Rio de Janeiro in 2016 is proposed. A system of differential equation models the spread of dengue amongst the resident population and a stochastic approximation is used to assess the risk to tourists. Historical reported dengue time series in Rio de Janeiro for the years 2000-2015 is used to find out the time dependent force of infection, which is then used to estimate the potential risks to a large tourist cohort. The worst outbreak of dengue occurred in 2012 and this and the other years in the history of Dengue in Rio are used to discuss potential risks to tourists amongst visitors to the forthcoming Rio Olympics.

Results: The individual risk to be infected by dengue is very much dependent on the ratio asymptomatic/symptomatic considered but independently of this the worst month of August in the period studied in terms of dengue transmission, occurred in 2007.

Conclusions: If dengue returns in 2016 with the pattern observed in the worst month of August in history (2007), the expected number of symptomatic and asymptomatic dengue cases among tourists will be 23 and 206 cases, respectively. This worst case scenario would have an incidence of 5.75 (symptomatic) and 51.5 (asymptomatic) per 100,000 individuals.

Rapid Risk Assessment: The risk of Zika virus to Canadians

Source: Public Health Agency of Canada. Rapid Risk Assessment: The risk of Zika virus to Canadians, posted July 2016. (Update summary).

• What's new: Several isolated instances of unusual transmission have now been documented; an asymptomatic sexual transmission (likely male-to-female), a likely female-to-male transmission, and a person-to-person transmission without sexual contact. All of these are thought to be rare modes of transmission, requiring particular circumstances to be realized, but these events demonstrate that they are possible.
• For most infected travellers, ZIKV will have little or no health impact (Low impact, with medium confidence). However, severe outcomes (e.g., Guillain Barré Syndrome) might occur in some affected individuals (High impact, high confidence).
• Based on recent evidence, we assess that there could be Very High impact (with high confidence) to the unborn children of women who become infected with ZIKV while pregnant.
• Canadian recommendations for the prevention and management of ZIKV-disease have been developed by the Committee to Advise on Tropical Medicine and Travel.

Note: This summary reflects the July 2016 update. Rapid Risk Assessments are updated on a regular basis and will be posted at the website above.