#14,242
Two days ago the World Health Organization announced the Successful Conclusion of Hajj 1440/2019 ; one ` . . . .without a single public health event or disease outbreak being reported among pilgrims performing the hajj.'
While a remarkable achievement - given the arrival and gathering of more than 2 million religious pilgrims from all over the globe - we'll have to wait at least couple of weeks before we'll know the full impact of this annual mass gathering event.Infectious diseases have incubation periods that can run from a couple of days to two weeks or longer, and so public health officials around the world will be keeping a close eye on people returning from this year's Hajj.
While the most obvious concern might be MERS-CoV, as we saw a few weeks ago in J, Epi & Global Health: Al-Tawfiq & Memish On Hajj Health Concerns, this emerging coronavirus is just one of many possible health threats at this large mass gathering event.
The most likely infectious disease threats involve mosquito borne illnesses (like Dengue, Chikungunya, Zika & Yellow Fever), tuberculosis, mumps, measles, chickenpox, norovirus and respiratory viruses like seasonal influenza & Rhinovirus.In 2015's EID Journal: ARI’s In Travelers Returning From The Middle East, researchers found respiratory infections are the most commonly reported illness among religious pilgrims.
Respiratory viruses generally all look alike in their early stages, making it difficult to identify and isolate those infected with more serious infections, like MERS (see BMC Inf. Dis.: Clinical Management Of Suspected MERS-CoV Cases).The UK's advice for travelers returning from the Middle East reads:
Pilgrims or travellers from the Middle East who develop symptoms (e.g. fever, cough or increasing breathlessness) within 14 days of their return to the UK should seek medical advice by calling their GP or NHS 111 and must mention which countries they have visited so that appropriate measures and testing can be undertaken.Over the next few weeks it is likely that we'll see reports of recent returnee's from the Hajj being tested for MERS-CoV, based on `respiratory' symptoms. Invariably, most (perhaps all) will turn out to be something far less exotic or dangerous than MERS.
Fortunately, summer is generally a slow time of the year for MERS cases in Saudi Arabia, and according to the Saudi MOH, case reports have dropped markedly the past two months.But as we've seen before, it only takes one infected traveler to spark a major outbreak (see Mapping The Korean MERS-CoV Superspreading Event), and MERS can be very difficult to diagnose.
Because of the difficulties in identifying cases, the WHO continues to advise:
It is not always possible to identify patients with MERS-CoV early because like other respiratory infections, the early symptoms of MERS-CoV are non-specific. Therefore, healthcare workers should always apply standard precautions consistently with all patients, regardless of their diagnosis.
Droplet precautions should be added to the standard precautions when providing care to patients with symptoms of acute respiratory infection; contact precautions and eye protection should be added when caring for probable or confirmed cases of MERS-CoV infection; airborne precautions should be applied when performing aerosol generating procedures.For some past blogs on the gaps in our knowledge and concerns over the under-detected MERS infections in the community, you may wish to revisit:
MERS-CoV In Humans: A Systematic Literature Review
J. Korean Med Sci: Atypical Presentation Of A MERS Case In A Returning Traveler From Kuwait
mBio: High Prevalence of MERS-CoV Infection in Camel Workers in Saudi Arabia
AJIC:Intermittent Positive Testing For MERS-CoV
JIDC: Atypical Presentation Of MERS-CoV In A Lebanese Patient
A Pandemic Risk Assessment Of MERS-CoV In Saudi Arabia
