the needle was removed water and blood sprayed out; the needle was removed water and blood sprayed out once the needle was removed from his arm; the needle was removed water and blood sprayed out/she was not sure he received the vaccine; This is a spontaneous report received from a contactable consumer (patient mother). This is a son case. A 20 years-old-male patient received first dose of BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE, Solution for injection, Lot number and Expiration date was not reported) via an unspecified route of administration on an unspecified date as a single dose for Covid-19 immunization. Medical history included autism spectrum disorder from an unknown date and unknown if ongoing (her 20-year-old son who has autism has received both doses of the Pfizer COVID-19 vaccine.) The patient's concomitant medications were not reported. The patient experienced the needle was removed water and blood sprayed out, the needle was removed water and blood sprayed out once the needle was removed from his arm and the needle was removed water and blood sprayed out/she was not sure he received the vaccine. Reporter reported that, patient was received the first dose of the Pfizer COVID vaccine and during vaccination after the needle was removed water and blood sprayed out. Patient was not sure he received the vaccine or if a blood vessel was hit during vaccination. As noted in the Fact Sheet for Recipients, patient should not get the PFIZER-BIONTECH COVID-19 Vaccine if he had a severe allergic reaction after a previous dose of the vaccine or if he had a severe allergic reaction to any ingredient of the vaccine. The decision to receive the second dose for any other reason cannot be made by PFIZER. We refer you to speak to your healthcare provider about the risks of the vaccine compared to the risks of potentially not being fully protected against COVID-19 infection. Your healthcare provider knows your health situation and has access to information that can better help inform this decision. If  patient should receive the second dose if during the first dose administration water and blood sprayed out once the needle was removed from his arm. No information regarding leakage of vaccine during first dose and recommendations regarding second dose. Reporter would like to know how people have reported blood clots after receiving the PFIZER COVID vaccine. She wanted to know what was the symptoms of blood clots and the age range for people who get blood clots. Reporter stated that patient has autism has received both doses of the PFIZER COVID-19 vaccine. During patient first dose a lot of blood came out and it was believed that some or most of the dose was lost.  Patient had his second dose 3 weeks ago and it went perfectly. Reporter was told by the vaccination provider that she had 3 options which were to repeat the first dose, have an antibody test done 3 weeks after the second dose was completed or do nothing and proceed as normal. She would like to know if an antibody test is recommended after receiving the PFIZER COVID-19 vaccine and what type and time range it should be done after the second dose to see if the vaccine was effective. Reporter had already reported the event that happened with patient. reporter further wanted to know why it was recommended by the HCP that patient receive antibody testing specifically at 3 weeks after his second dose of the PFIZER COVID-19 vaccine to check for antibody levels. Reporter heard the first dose of the Pfizer COVID-19 vaccine is about 80% effective. Reporter wanted to know if this was true and she heard that PFIZER was looking into doing a third dose or booster dose and wanted to know if there was more information about this booster dose. The need for a booster dose of PFIZER-BIONTECH COVID-19 vaccine based on duration of protection or impact of variant strains has not yet been determined. On February 25, PFIZER and BIONTECH announced they initiated an evaluation of the safety and immunogenicity of a potential third dose of the PFIZER-BIONTECH COVID-19 vaccine (BNT162b2) to understand the effect of a booster on immunity against COVID-19 caused by the currently circulating and potential newly emerging variants. It was important to have a vaccine technology that allows us to both provide boosting doses if needed and to address potential changes in the virus itself if a new variant emerges that the vaccine does not protect against.  While we have not seen any evidence that the circulating variants result in a loss of protection provided by our vaccine in our laboratory studies, we are taking multiple steps to be ready in case a strain becomes resistant to the vaccine. The administration of more than a 2-dose series of PFIZER BIONTECH COVID-19 Vaccine was not approved. PFIZER was unable to make any recommendations regarding administration of a booster dose of PFIZER-BIONTECH COVID-19 Vaccine. Pfizer did not suggest or recommend the use of the vaccine in any manner other than as described in the authorized EUA Prescribing Information. Note to frontline: This FAQ should only be used if someone specifically asks about the Pfizer statement on booster doses. For all other general inquiries about booster doses, please refer to the SRD titled "Administration of More Than a 2-Dose Series (Booster Dose). She stated that the HCP who administered her son Pfizer COVID-19 vaccines told her that they could give another dose since it was unclear if he received the full first dose. She wanted to know if it was suggested to receive more than 2 doses of the PFIZER COVID-19 vaccine after that type of incident. The outcome of all event was unknown.  No follow-up attempts are needed; information about lot/batch number cannot be obtained.  Amendment: This follow-up report is being submitted to amend previously reported information: The event with verbatim "the needle was removed water and blood sprayed out" was recoded to "wrong technique in product usage process", "vaccination site bleeding" and "underdose". The event "Inappropriate route of vaccination" was deleted as the route of vaccination was not reported. The information about mother was deleted from narrative and the at-risk classification was deleted. New information on (26May2021) included: Clinical information was updated.  Follow-up attempts are completed; information about lot/batch number cannot be obtained.