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What to expect following BCG vaccination

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What to expect following BCG vaccination

Recruitment ended in March 2021 for this multi-centre randomised controlled clinical trial of the BCG vaccine against COVID-19.

Half of healthcare workers received the BCG vaccine to test whether it can protect those exposed to SARS-CoV-2 from developing severe symptoms by boosting their frontline immunity. The below information was provided at recruitment:

What to expect following the BCG vaccination

  • The BCG vaccination is given just under the skin (into the ‘intradermal’ layer) of the left upper arm 
  • The usual expected reaction to BCG vaccination is redness and/or a small ‘papule’ (a pimple or lump) at the injection site that appears weeks to months after vaccination 
  • A few weeks later, the papule usually softens and breaks down to a small ulcer (an open sore - usually less than 15 mm in diameter) 
  • The ulcer may last from weeks to months 
  • Once the ulcer has healed, this usually (but not always) leaves a small flat scar 

Care of the injection site 

  • Keep the area clean and dry 
  • Normal bathing is acceptable – pat dry after washing 
  • A temporary dry dressing with gauze may be used if the area starts to ooze 
  • A sterile alcohol swab may be used to clean the area if required 
  • Do not apply ointment, antiseptic creams, sticking plaster or band aids 
  • Do not attempt to squeeze any pus out of the papule or ulcer that develops 

Rare complications following BCG vaccine

  • A large abscess (collection of pus) at the injection site 
  • Infection of the glands in the left armpit (‘axillary lymph nodes’) causing tenderness and swelling under the arm ‘Keloid’ scarring (very noticeable scarring on the skin) 
  • Severe immediate allergic reaction (very rare), please stay on the hospital grounds for the next 20mins 

When to seek medical advice 

  • If you notice any severe or rare reactions, such as a large persistent discharging abscess at the injection site 
  • If you notice swelling or tenderness of the glands (‘lymph nodes’) in the left armpit 

Who to contact for advice

How to take the best picture of your vaccination site

  • Attach a standard-sized object to your upper arm (e.g. coin, or beer bottle cap) using rolled up sticky tape or BluTack, adjacent to the vaccination site.
  • You can also place a ruler or a measuring tape adjacent to the vaccination site.
  • Hold your phone approx. 15 cm away from the area being photographed.
  • Ensure the entire injection site and coin are in the photo and in focus.

Here is an example:

BCG vaccination site