#14,192
After very active first quarter of 2019 - where we saw 120 MERS cases in under 100 days - MERS activity in Saudi Arabia has slowed, averaging fewer than 3 cases a week since early May. Last week (epi week 28), only one case was reported.
Today, however, the Saudi MOH is reporting three new cases over the past two days. It appears all three are hospitalized in Riyadh, but 1 case (70,M) is listed as hailing from Buraidah.All three are listed as `primary' - suggesting no epidemiological links between them - but the source of their infection remains unknown. Camel contact on all three is listed as `Unknown'.
While MERS reports from Saudi Arabia have been reduced the past couple of months - this years' Hajj is just over 3 weeks away - when roughly 2 million religious pilgrims will visit the Kingdom and congregate in Mecca, Medina, and other Holy sites.
Mass gathering events such as the Hajj, the Super Bowl, Olympics, and Carnival all bring with them some infectious disease transmission risks. The CDC's Travel advice for the Hajj states:
Why consider health risks for Hajj?
The Hajj, or pilgrimage to Mecca, Saudi Arabia, is one of the world’s largest mass gatherings. In 2019, Hajj will take place August 9–14. Because of the crowds, mass gatherings such as Hajj are associated with unique health risks. Before you go, visit a travel health specialist for advice, make sure you are up-to-date on all routine and travel-related vaccines, and learn about other health and safety issues that could affect you during your trip.
The most likely infectious disease outbreak scenarios involve mosquito borne illnesses (like Dengue & Chikungunya, Zika), tuberculosis, mumps, measles, chickenpox, norovirus and respiratory viruses like seasonal influenza & Rhinovirus.
Still, it isn't lost on public health officials that the Middle East is also home to MERS-CoV, and the long incubation period (up to 14 days) and often subtle early symptoms (or asymptomatic carriage) of MERS makes early detection difficult (see BMC Inf. Dis.: Clinical Management Of Suspected MERS-CoV Cases).
The often heightened level of `viral noise’ among travelers returning from the Middle East makes it extremely challenging to identify and isolate those infected with MERS, Avian flu, or other highly virulent viruses (see MERS: The Limitations Of Airport Screening).
While we've been lucky in the past, with no large MERS outbreaks linked
to the Hajj, the possibility of seeing one or more infected pilgrims
returning to their home countries while silently incubating the virus is
an annual concern.
