Table Of ContentCorrespondence
Tale of three seeding
Saudi Arabians
patterns of SARS-CoV-2 Non-Saudi Arabians
Lancet Infect Dis 2020
in Saudi Arabia
Al Jowf Nothern Published Online
Borderlands May 19, 2020
Human mobility patterns are deter- https://doi.org/10.1016/
Tabuk S1473-3099(20)30425-4
minants of disease transmission. This
Hail
is particularly relevant for severe acute
respiratory syndrome corona virus 2 Qasim
Eastern
(SARS-CoV-2) transmission in Saudi Riyadh Province
Medina
Arabia (population 34 million), which
experiences three types of population
movements. First is the international 6% 33%
6%
and domestic movement of pilgrims 67%
Mecca 94%
in Saudi Arabia. On average each 94%
month about 1 million incoming Al Bahah
pilgrims from 180 countries merge Asir
with about 1 million Saudi-national
Najran
Sunni pilgrims (75% of the Saudi
Jazan
population) in Saudi Arabia’s two holy
sites and the nearest entry port of
Jeddah.1 Second is the returning Shiite Figure: COVID-19 distribution in Saudi Arabia on March 15, 2020, by nationality
Saudi-national pilgrims (4·9 million COVID-19=coronavirus disease 2019.
Shiite population in Saudi Arabia) who
travel to Iran and Iraq for pilgrimage. patterns, by April 2, 2020, the second region was reported on March 10
Men and women older than 60 years had the greatest affect on accelerating among four returning Saudi pilgrims.
are overrepresented among pilgrims. domestic transmission in Saudi Arabia, Saudi Arabia had not recognised
Third is routine travel to and from with highest acceleration of cases seen the impact of Qom pilgrimage4
Saudi Arabia by Saudis, permanent in the eastern region (99 cases per on SARS-CoV-2 transmission in
residents, and non-pilgrim visitors for 100 000). Per 100 000 population, eastern Saudi Arabia until then. The
commerce and tourism, estimated to Mecca and Riyadh had 17 cases and country’s attempt to identify and
be about 3 million people each month. eight cases, respectively, on April 2. quarantine returning Saudi pilgrims
We observed three outbreak seeding Saudi Arabia’s ten quarantined proved inefficient initially owing to
patterns in Saudi Arabia in the early student evacuees from China were non-direct routes of travel to Saudi
phase of the coronavirus disease 2019 reported on Feb 16 to have tested Arabia through Gulf Cooperation
(COVID-19) epidemic that match the negative for SARS-CoV-2.2 The Council countries. Saudi Arabia then
three types of population movements country’s suspension of pilgrimage encouraged returning citizens to
(figure). First, transmission related visas for international visitors on voluntarily declare travel to Iran and
to international pilgrims in holy sites Feb 27 and for all people by March 4 repatriated stranded citizens using
in Mecca and Medina region, largely probably helped delay detection of special flights.
among the non-Saudi population the first case in the Mecca region until Saudi Arabia mitigated inter-
(49 [94%] of 52 cases). Second, March 10. Saudi Arabia implemented national and domestic superspreader
transmission among returning comprehensive pandemic mitigation transmission of SARS-CoV-2 in its
Saudi Shiite pilgrims in the eastern efforts3 incrementally during international pilgrim sites with early
province, affecting mostly Saudi March 8–21. restrictions of access to its holy
citizens (45 [94%] of 48 cases). In the early phase of the epidemic, sites. Saudi Arabia was unsuccessful
Third, general non-specific spread the high proportion of COVID-19 in limiting transmission among
by routine international travel in the diagnoses in the Riyadh region that returning Saudi nationals who
political and diplomatic hub of Riyadh were among Saudi nationals (67%) participated in an unmitigated
province, mostly among the Saudi might have resulted from entry superspreader event. The ongoing
population (12 [67%] of 18 cases). restrictions on non-Saudi people and domestic transmission in the country
The remaining provinces of Saudi increases in returning Saudi citizens is largely fueled by returning Saudi-
Arabia did not have COVID-19 cases in who might have been exposed national pilgrims.
the early phase. Of the three seeding overseas. The outbreak in the eastern
We declare no competing interests.
www.thelancet.com/infection Published online May 19, 2020 https://doi.org/10.1016/S1473-3099(20)30425-4 1
Correspondence
*Ziad A Memish, Nawfal Aljerian, of Sciences, Technique and Technology, Bamako, 3 Ebrahim SH, Ahmed QA, Gozzer E,
Shahul H Ebrahim Mali (SHE) Schlagenhauf P, Memish ZA. Covid-19 and
community mitigation strategies in a
[email protected] 1 Ebrahim SH, Memish ZA. COVID-19: preparing pandemic. BMJ 2020; 368: m1066.
for superspreader potential among Umrah
Research & Innovation Center, King Saud Medical pilgrims to Saudi Arabia. Lancet 2020; 4 Tuite AR, Bogoch II, Sherbo R, et al. Estimation
City (ZAM), and Medical Referral Center, National 395: e48. of coronavirus disease 2019 (COVID-19) burden
Health Command Center (NA), Ministry of Health, 2 Ministry of Health. Ten Saudi students ainnfde cptoiotnen frtoiaml f oIrra inn.t Aernnna Itniotenranl Mdiesdse 2m02in0a;t ion of
Riyadh, Saudi Arabia; College of Medicine, Alfaisal evacuated from China declared coronavirus- published online March 16. https://doi.
University, Riyadh, Saudi Arabia (ZAM); King Saud free. Feb 16, 2020.https://www.moh.gov.sa/ org/10.7326/M20-0696.
bin Abdulaziz University for Health Sciences, Riyadh, en/Ministry/MediaCenter/News/Pages/
Saudi Arabia (NA); Hubert Department of Global News-2020-02-16-006.aspx (accessed
Health, Rollins School of Public Health, Emory April 4, 2020).
University, Atlanta, GA, USA (ZAM); and University
2 www.thelancet.com/infection Published online May 19, 2020 https://doi.org/10.1016/S1473-3099(20)30425-4
