Have a fever with a high of 99.6 Fahrenheit; felt winded like she has exerted herself more than expected/shortness of air; Coughing/cough got worse; She is covid positive/Tested positive for COVID 19; She is covid positive/Tested positive for COVID 19; Shortness of breath/Shortness of breath was reported as worsened/feels winded; Tachycardia; Has been sick ever since; Felt like she was in a fog, on a cloud, heavy and out of it; She felt hot and weird but had no fever; Headache; Burning sensations in her legs; Extreme fatigue, want to go to bed; headache went away and she felt like the congestion was clearing up some; Arm was sore; This is a spontaneous report from a contactable ICU nurse (patient [Registered nurse ADN]) via Pfizer-sponsored program. A 38-year-old female patient received single dose of BNT162B2 (lot number: EK5730) , via an unspecified route of administration (right arm) on 16Dec2020 20:30 for immunization (for front line health care worker). Medical history included allergies; acid reflux; patent foramen ovale (PFO); supraventricular tachycardia (SVT) without treatment, vitamin D low and ongoing smoker. The patient had no other history/family history. Concomitant medication included loratadine (CLARITIN) taken for at least 5 years for allergy, famotidine from Dec2020 for acid reflex, and vitamin D taken for 5 or more years for vitamin D low; all given orally and were ongoing. The patient had no other prior vaccines within 4 weeks of Covid vaccination. Patient had been taking Covid tests on and off due to her immunocompromised daughter. On 15Dec2020 she took the PTR that took three to four days for results; she tested negative for Covid and was completely asymptomatic. She then received the COVID 19 vaccine 16Dec2020. Her test was positive for COVID 19 on 18Dec2020 and she had been sick ever since. She received the vaccine at the hospital where she works. The vaccine was not administered at facility. She further reported she was fine after getting the COVID 19 vaccine. Her right arm was sore/ started to hurt about four or five hours later on 16Dec2020 but then was fully after 24 to 48 hours. She started to feel sick on 18Dec2020 (Friday evening). States she went to bed Friday morning after the night shift. She felt fine, better than normal. That same day (18Dec2020) she woke up at 1700 and felt like she was in a fog, on a cloud, heavy and out of it. She walked around for a while and that sensation didn't go away. She felt hot and weird but had no fever. Then at 1830 she got the alert on her phone that told her she was positive for COVID 19. She started to feel other symptoms on 18Dec2020 including headache, shortness of breath, tachycardia, burning sensations in her legs; extreme fatigue, wanting to go to bed that persisted from Friday to Sunday. Then on 20Dec2020, Sunday afternoon, her headache went away and she felt like the congestion was clearing up some. Mentions she did have a fever (onset date unspecified) with a high of 99.6 Fahrenheit; but it went back down to 99.0 Fahrenheit (date/s unspecified). On 20Dec2020 the patient experienced coughing. On 21Dec2020 (Monday) she started coughing more but states her O2 was fine and her breathing was okay. However, when walking around she felt winded like she has exerted herself more than expected. She then clarified that on 21Dec2020, she experienced shortness of air and the cough got worse but it has now plateaued. She did call her HCP and they were holding off on treatment at the time. No investigation assessment was performed. The patient was not admitted to an Intensive Care Unit. The patient did not display clinical signs at rest indicative of severe systemic illness nor did she require supplemental oxygen or receive mechanical ventilation. No preexisting diseases worsened during the SARS-CoV2 infection. The patient considered shortness of breath, and tachycardia as serious: medically significant while the events headache, burning sensations in her legs, fatigue, Coughing, and feels winded were considered as not serious. The events headache, shortness of breath, tachycardia, burning sensations in her legs, fatigue, Coughing, and feels winded were ongoing at the time of reporting. Shortness of breath worsened. The patient recovered from arm was sore on an unspecified date in Dec2020; and was recovering from tachycardia, sick, headache and congestion. The outcome of felt like she was in a fog, on a cloud, heavy and out of it; felt hot, and fever was unknown while not recovered for the other events.; Sender's Comments: Based on available information, a possible contributory role of the subject product, BNT162B2 vaccine, cannot be excluded for the reported events due to temporal relationship.  However, the reported events may possibly represent intercurrent medical conditions in this patient.  There is limited information provided in this report.  Additional information is needed to better assess the case, including complete medical history, diagnostics including chest x-ray, counteractive treatment measures and concomitant medications.  This case will be reassessed once additional information is available.  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 to Regulatory Authorities, Ethics Committees and Investigators, as appropriate.