The number of COVID-19 patients in Syria started to increase since early June after the reduction of infection control measurements applied by the government (15). The official numbers announced from the Syrian Ministry of Health are not reliable because of the lack of COVID-19 diagnosis equipment in the country - in our study, only 2.6% of participants underwent PCR tests to confirm COVID-19- and due to the sanctions currently applied, which made the health response to this pandemic very limited. Moreover, the Syrian health system, which has already been destroyed by years of war, is currently suffering from sanctions, which justify the concerns that the true numbers of cases are much higher (11,16). Therefore, it was of great importance to document the prevalence of COVID-19 symptoms among the Syrian population and to try to estimate the average number of patients despite the official numbers, which is very limited. This large-scale cross-sectional study included over 5000 Syrian citizens, which can provide better insight into the true percentage and prevalence of COVID-19 suspected cases in Syria.
The results of this study showed a high prevalence of COVID-19 symptoms among the Syrian population, which supports the hypothesis of a higher rate of spread of the disease in Syria. The most common symptoms were fatigue (body ache), headache, sore throat, fever and cough. On the other hand, dermal manifestations and diarrhea were less common in the Syrian population. This result agrees partially with the meta-analysis that summarized the results of 43 studies, and the most common symptoms were fever (83%), cough (60%) and fatigue (38%) (17). A high prevalence of smell and taste loss occurred in the Syrian population, which was similar to other cross-sectional studies (18,19).
The duration of carrying corona virus is on average 12 days (16). The results of our study showed less average duration of the symptoms; however, the duration might be longer because participants were asked to answer about the persistence of the symptoms, and the patients might be infected without any clinical symptoms (20). Moreover, patients with severe symptoms showed a longer duration of the symptoms, and previous studies showed a correlation between the duration of the symptoms, age, and severity of the symptoms (21).
Ten percent of the sample had previously diagnosed chronic diseases, and systematic reviews demonstrated that one major determent of COVID-19 severity is preexisting chronic condition, which confirms the results of this study (22,23).
It is of great importance to study and understand the process prevalence and response to COVID-19 in Syria because Syria has faced 10 long years of war, which laterally destroyed its health system, and currently under sanctions, which made it even harder for the under-poverty-line population to survive during this pandemic. With the lack of real and effective governmental measurements and decreased public awareness, we may be going straight ahead towards herd immunity, assuming an R0 estimate of 3 for SARS-CoV-2, and the herd immunity threshold is estimated to be 67%-80% (24,25). Considering that 67% of our sample reported COVID-19 symptoms, we may be close to achieving herd immunity, but this cannot be confirmed without widespread screening PCR tests to confirm the disease. Additionally, with little understanding (until the date of writing this manuscript) of the host immune responses against SARS-Co V2, we cannot rely on the principle of herd immunity.
Several promising vaccines for SARS-Co V2 are currently being developed (26), but until proven safe and effective, several measures should be taken. One successful experience in this context is the Jordanian experience, where the government implanted several measurements, such as travel restrictions for non-Jordanians and mandatory quarantine of 14 days for Jordanians arriving from abroad, strict rules that banned all social events and public and religious gatherings that slowed down COVID-19 spreading (27). Another beneficial measurement is enforcing a law to wear face masks in public, especially in closed, minimally ventilated, and crowded places. 80% adoption of moderately face masks can reduce deaths caused by COVID-19 by approximately 40% (28)