Interim guidelines for the use of SARS-CoV-2 vaccine

31 August 2021


Ever since COVID-19 was announced as a worldwide pandemic, a number of vaccines were developed and approved for use against SARS-CoV-2. Currently, in Saudi Arabia, there are 3 vaccines approved for use against SARS-CoV-2, AstraZeneca, Pfizer-BioNTech, and lately Moderna. 

Both Pfizer and Moderna were developed using the same technology, which is mRNA, while AstraZeneca was developed using a replication-deficient simian adenovirus vector.

Approved vaccines in Saudi Arabia


BNT162b2 is one of the available vaccines that are proven effective against SARS-CoV-2. The vaccine went through the 3-phase clinical trial where close to 44 thousand participants were recruited, around 18 thousand in each arm. The vaccine showed around 95% in preventing COVID-19 in the intervention arm. 

On the 11th of December, the FDA approved the vaccine for emergency use authorization (EUA) in individuals older than 16 years of age. The SFDA approved the vaccine as well to be used in the kingdom of Saudi Arabia. 



AZD1222 is a product of collaboration between Oxford University and pharmaceutical company AstraZeneca, the vaccine is reported to have an efficacy of 63% according to clinical trials. According to the literature the vaccine is intended to be used in the age group of 18 years and older.



Moderna vaccine is a two doses mRNA vaccine that has been developed by Moderna.

According to the clinical trials, the vaccine efficacy is estimated at 94% 14 days after the second dose. 

On the 9th of July, the SFDA has approved the use of the vaccine in the Kingdom of Saudi Arabia.


Effectiveness against variants: 

Recent COVID-19 variants have raised plenty of questions regarding transmissibility, severity, and vaccine efficacy.

Though some studies suggest that there’s a reduction In the efficacy of vaccines, according to Public Health England, individuals vaccinated with either Pfizer or AstraZeneca are 92-96% less likely to be hospitalized with a severe form of COVID-19

Pfizer-BioNTech – (BNT162b2)
Oxford-AstraZeneca (AZD1222)
The vaccine is administered through an intramuscular route in 2-dose series, 0.3 ml each.

The second dose should be administered within the range of 19-23 days after the first dose has been administered.

An interval of 42 days between the doses is acceptable.

Studies showed that the level of efficacy following the first dose is only 52%.

BNT162b2 should be administered alone and spaced carefully, 14 days prior and 14 days after any administration of any type of vaccine.

If administered within that range, no doses shouldn’t be repeated.

The vaccine is administered through the intramuscular (Deltoid) route in 2-dose series, 0.5 ml each.

The duration between doses should be between 8-12 weeks. If the second dose is administered less than 4 weeks after the first, the dose does not need to be repeated.

If the administration of the second dose is inadvertently delayed beyond 12 weeks, it should be given at the earliest possible opportunity. It is recommended that all vaccinated individuals receive two doses.

There should be a minimum interval of 14 days between the administration of this vaccine and any other vaccine against other conditions.

The vaccine is administered through an intramuscular route in 2-dose series, 0.5 ml each.

The duration between the doses should be 28 days apart. If the second dose is delayed beyond that, the series shouldn’t be repeated.

An interval of 42 days between the doses is acceptable.

There should be a minimum interval of 14 days between the administration of the Moderna vaccine and any other vaccine.

Age group
12 years old and above18 years old and above12 years old and above
There isn’t available data on the safety and effectiveness of administrating different types of vaccines.

Individuals should continue the series using the same type of vaccine unless:

  • unavailability of the same type of vaccine.
  • Anaphylactic reaction to the first dose of vaccine.
Prior history of COVID-19 infection or Exposure:  
  • Persons with acute PCR-confirmed COVID-19, including those with the onset of PCR-confirmed infection between doses, should not be vaccinated until after they have recovered from acute illness and the criteria for discontinuation of isolation have been met
  • Subjects who had recent exposure to confirmed cases shouldn’t be vaccinated until the quarantine period is over.


Subjects who received plasma therapy during their infection:   

They should delay their vaccination until 90 days have passed to ensure there isn’t interference from antibodies received by plasma and vaccine response. 


Additional 3rd dose: 
  • Recent data suggest that individuals who are moderate to severely immunocompromised are less likely to respond to the vaccine and may benefit from booster 3rd dose.
  • This group includes:
    • Post organ transplantation.
    • Active treatment with high-dose corticosteroids or other drugs may suppress the immune response.
  • These individuals should discuss the vaccination plan with their treating physician.
  • 3rd dose can be taken after 2 months have passed from the 2nd dose.
  • Subjects who are known to have an allergy against any of the vaccine components should not be vaccinated until further evidence is available.
  • Subjects who have a history of anaphylaxis following any type of vaccination or intramuscular injections consult their physician before taking the vaccine.
  • Subjects who experience anaphylaxis shock following the first dose of the vaccine should not receive the second dose.
  • Those who have a history of mild to moderate allergy and using anticoagulants or bleeding disorders should be observed for 30 minutes following receiving the vaccine.
  •  Car drivers should be observed for 15 minutes.
  • Anyone with an acute febrile illness (body temperature over 38.5) should postpone vaccination until afebrile.
  • The presence of minor infection, such as a cold, or low-grade fever should delay vaccination until the resolution of symptoms.
Special Considerations

To this date, data is limited about the safety of the vaccine in immunocompromised patients (HIV, patients on immunosuppressant drugs, and immunocompromising diseases).

Risk and benefit should be evaluated by the treating physician and the discussion with the patient about the available data on safety before administration of the vaccine.

They should be educated about the type of the vaccine and that it doesn’t contain live viruses or attenuated.

They should understand that the efficacy in their condition is still to be evaluated and may differ from the typical response. They should follow precautions after vaccination.


Persons with autoimmune conditions: 

The available data on the safety and efficacy of the available vaccines is limited in individuals with autoimmune diseases. However, due to severe forms of the disease that can develop in this group, vaccines should be considered and discussed with the treating physician.

 Pregnancy and breastfeeding:  

To this date, data is limited about the safety of the vaccine in pregnant women, though the vaccine is not a live vaccine.

Pregnant women or those planning to conceive in the near future can receive the vaccine as they are more prone to severe forms of the disease, and should be educated about the limited data available on safety.

It’s not believed that the vaccine can adversely affect breastfeeding, and women who are at risk of infection should be vaccinated because of the higher benefits to harm ratio.


Anticoagulation therapy and bleeding disorders:  

Prior to vaccination, subjects on anticoagulant therapy or who have bleeding disorders should counsel their treating physician regarding the safety of injection.

Patients who are on warfarin can be vaccinated via the intramuscular route if they are up to date with their INR testing and are below the upper level of the therapeutic range. The vaccine can be taken as well in patients on Direct Oral Anticoagulants if they are stable. 

Following the administration of the injection, the health care provider should monitor the injection site for any bleeding and educate the subject about the risk of hematoma from the injection.

During counseling, it’s important to emphasize the importance of continuing to adhere to universal masking, hand hygiene, and social distancing, especially between the doses.

Educate the receiving subject about the possible side effect that is common to the vaccine such as (pain, swelling at the site of the injection, fever, fatigue, and myalgia) and to report to a health care facility if any other side effects out of the norm appear.

*Disclaimer: This guideline is updated according to the latest available data and evidence.