On 16Jan2021, both ears were clogged but I couldn't hear well out of left ear and there is a constant hum in it. On 17Jan, I had pain in left ear but it went away. My left ear still is clogged; has decreased hearing/decreased hearing of lower register; On 16Jan2021, both ears were clogged but I couldn't hear well out of left ear and there is a constant hum in it. On 17Jan, I had pain in left ear but it went away. My left ear still is clogged; On 16Jan2021, both ears were clogged but I couldn't hear well out of left ear and there is a constant hum in it. On 17Jan, I had pain in left ear but it went away. My left ear still is clogged; On 16Jan2021, both ears were clogged but I couldn't hear well out of left ear and there is a constant hum in it. On 17Jan, I had pain in left ear but it went away. My left ear still is clogged; This is a spontaneous report from a contactable nurse (patient). A 50-year-old female patient received the second dose of bnt162b2 (PFIZER-BIONTECH COVID-19 MRNA VACCINE, lot number: EL1283), via an unspecified route of administration administered in left arm in the hospital on 08Jan2021 07:30 as SINGLE DOSE for COVID-19 immunisation. The patient had no other vaccine in four weeks. The patient had unspecified medical history and concomitant medications in two weeks. The patient had no known allergies. The patient had no COVID prior vaccination and was not tested for COVID post vaccination. Historical vaccine includes first dose of bnt162b2 (PFIZER-BIONTECH COVID-19 MRNA VACCINE, lot number: EK5730) administered in left arm on 18Dec2020 at 06:30 PM for COVID-19 immunisation. On 16Jan2021, both ears were clogged but patient couldn't hear well out of left ear and there was a constant hum in it on 16Jan2021 at 06:00 AM. On 17Jan2021, the patient had pain in left ear but it went away. Her left ear still was clogged, has constant hum and has decreased hearing on 17Jan2021. Right ear hearing was always fine and clogged feeling went away in two weeks. The patient saw ear, nose, and throat (ENT) on 19Jan2021, patient was started on steroids. The patient had magnetic resonance imaging (MRI)and several types of hearing tests on 19Jan2021. MRI was normal. Hearing tests showed decreased hearing of lower register. One doctor thought she should mention it since it happened within 8 days of receiving her second vaccination. The events resulted in doctor or other healthcare professional office/clinic visit. Therapeutic measures were taken as a result of all events which includes MRI, steroids, and hearing test. The patient recovered from ear pain on an unspecified date while outcome of the rest of the events was not yet recovered.; Sender's Comments: Based on the information provided, and on plausible temporal association,  the Company  assessed that a reasonable possibility could not be completely excluded that the reported event Hearing loss (both ears were clogged but I couldn't hear well out of left ear and there is a constant hum in it) was related to the  PFIZER-BIONTECH COVID-19 VACCINE. The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified.