inclusion criteria: * ≥18 years old when enrolled; * participants signing the informed consent; * being able to participate in all planned follow-ups and accomplish all research procedures including completing a diary card and coming back for interview; * having not been administered any pneumonia vaccine or covid-19 vaccine, and having not been administered an influenza vaccine in the current season before enrollment; * ≥14 days from the most recent vaccination; * before enrollment, the body temperature is ≤37.0c as confirmed by medical history and clinical examination. exclusion criteria for the first dose: * having a history of covid-19 or a positive nucleic acid test for covid-19; * having a history or a family history of allergy, convulsion, epilepsy, brain disease, or mental illness; * being allergic to any component of vaccines, or having a history of severe allergic reaction to any vaccine; * having immunodeficiency disorder, during treatment of malignant tumor, having immunodeficiency induced by immunosuppressants (oral steroid hormones) or hiv, or having a family member with close contact who suffers from congenital immune disorder; * having injection of non-specific immunoglobulin within 1 month prior to enrollment; * having acute febrile illness or communicable disease; * having a history of confirmed thrombocytopenia or other coagulation disorders, which may cause contraindications for a subcutaneous injection; * having severe chronic disease or acute exacerbation of chronic disease, or having uncontrolled hypertension or diabetes; * having various infectious, pyogenic, or allergic skin diseases; * women in pregnancy or lactation or participants who plan for a baby within 3 months after vaccination should delay the vaccination; * having any condition that may affect trial assessment as determined by researchers. exclusion criteria for the second dose: * having any serious adverse event related to the first dose vaccination; * after vaccination, having systemic adverse reaction or allergic reaction with a severity of grade 3 or higher as determined by researchers; * having a newly emerging condition that meets the exclusion criteria for the first dose; * having any condition that may affect trial assessment as determined by researchers.

inclusion criteria: * ≥18 years old when enrolled; * participants signing the informed consent; * being able to participate in all planned follow-ups and accomplish all research procedures including completing a diary card and coming back for interview; * having not been administered any pneumonia vaccine or covid-19 vaccine, and having not been administered an influenza vaccine in the current season before enrollment; * ≥14 days from the most recent vaccination; * before enrollment, the body temperature is ≤37.0c as confirmed by medical history and clinical examination. exclusion criteria for the first dose: * having a history of covid-19 or a positive nucleic acid test for covid-19; * having a history or a family history of allergy, convulsion, epilepsy, brain disease, or mental illness; * being allergic to any component of vaccines, or having a history of severe allergic reaction to any vaccine; * having immunodeficiency disorder, during treatment of malignant tumor, having immunodeficiency induced by immunosuppressants (oral steroid hormones) or hiv, or having a family member with close contact who suffers from congenital immune disorder; * having injection of non-specific immunoglobulin within 1 month prior to enrollment; * having acute febrile illness or communicable disease; * having a history of confirmed thrombocytopenia or other coagulation disorders, which may cause contraindications for a subcutaneous injection; * having severe chronic disease or acute exacerbation of chronic disease, or having uncontrolled hypertension or diabetes; * having various infectious, pyogenic, or allergic skin diseases; * women in pregnancy or lactation or participants who plan for a baby within 3 months after vaccination should delay the vaccination; * having any condition that may affect trial assessment as determined by researchers. exclusion criteria for the second dose: * having any serious adverse event related to the first dose vaccination; * after vaccination, having systemic adverse reaction or allergic reaction with a severity of grade 3 or higher as determined by researchers; * having a newly emerging condition that meets the exclusion criteria for the first dose; * having any condition that may affect trial assessment as determined by researchers.

inclusion criteria: - ≥18 years old when enrolled; - participants signing the informed consent; - being able to participate in all planned follow-ups and accomplish all research procedures including completing a diary card and coming back for interview; - having not been administered any pneumonia vaccine or covid-19 vaccine, and having not been administered an influenza vaccine in the current season before enrollment; - ≥14 days from the most recent vaccination; - before enrollment, the body temperature is ≤37.0c as confirmed by medical history and clinical examination. exclusion criteria for the first dose: - having a history of covid-19 or a positive nucleic acid test for covid-19; - having a history or a family history of allergy, convulsion, epilepsy, brain disease, or mental illness; - being allergic to any component of vaccines, or having a history of severe allergic reaction to any vaccine; - having immunodeficiency disorder, during treatment of malignant tumor, having immunodeficiency induced by immunosuppressants (oral steroid hormones) or hiv, or having a family member with close contact who suffers from congenital immune disorder; - having injection of non-specific immunoglobulin within 1 month prior to enrollment; - having acute febrile illness or communicable disease; - having a history of confirmed thrombocytopenia or other coagulation disorders, which may cause contraindications for a subcutaneous injection; - having severe chronic disease or acute exacerbation of chronic disease, or having uncontrolled hypertension or diabetes; - having various infectious, pyogenic, or allergic skin diseases; - women in pregnancy or lactation or participants who plan for a baby within 3 months after vaccination should delay the vaccination; - having any condition that may affect trial assessment as determined by researchers. exclusion criteria for the second dose: - having any serious adverse event related to the first dose vaccination; - after vaccination, having systemic adverse reaction or allergic reaction with a severity of grade 3 or higher as determined by researchers; - having a newly emerging condition that meets the exclusion criteria for the first dose; - having any condition that may affect trial assessment as determined by researchers.

inclusion criteria: - ≥18 years old when enrolled; - participants signing the informed consent; - being able to participate in all planned follow-ups and accomplish all research procedures including completing a diary card and coming back for interview; - having not been administered any pneumonia vaccine or covid-19 vaccine, and having not been administered an influenza vaccine in the current season before enrollment; - ≥14 days from the most recent vaccination; - before enrollment, the body temperature is ≤37.0c as confirmed by medical history and clinical examination. exclusion criteria for the first dose: - having a history of covid-19 or a positive nucleic acid test for covid-19; - having a history or a family history of allergy, convulsion, epilepsy, brain disease, or mental illness; - being allergic to any component of vaccines, or having a history of severe allergic reaction to any vaccine; - having immunodeficiency disorder, during treatment of malignant tumor, having immunodeficiency induced by immunosuppressants (oral steroid hormones) or hiv, or having a family member with close contact who suffers from congenital immune disorder; - having injection of non-specific immunoglobulin within 1 month prior to enrollment; - having acute febrile illness or communicable disease; - having a history of confirmed thrombocytopenia or other coagulation disorders, which may cause contraindications for a subcutaneous injection; - having severe chronic disease or acute exacerbation of chronic disease, or having uncontrolled hypertension or diabetes; - having various infectious, pyogenic, or allergic skin diseases; - women in pregnancy or lactation or participants who plan for a baby within 3 months after vaccination should delay the vaccination; - having any condition that may affect trial assessment as determined by researchers. exclusion criteria for the second dose: - having any serious adverse event related to the first dose vaccination; - after vaccination, having systemic adverse reaction or allergic reaction with a severity of grade 3 or higher as determined by researchers; - having a newly emerging condition that meets the exclusion criteria for the first dose; - having any condition that may affect trial assessment as determined by researchers.

inclusion criteria: - subjects aged no younger than 18 years old on the day of recruitment; - with valid informed consent signed by subject personally; - subject is able to attend all scheduled appointments and comply with all study instructions; - subjects have not received any seasonal influenza vaccine, pneumonia vaccine, or covid-19 vaccine before; - inoculated with any vaccine within no less than 14 days of the study; - axillary temperature ≤37.0℃

inclusion criteria: - subjects aged no younger than 18 years old on the day of recruitment; - with valid informed consent signed by subject personally; - subject is able to attend all scheduled appointments and comply with all study instructions; - subjects have not received any seasonal influenza vaccine, pneumonia vaccine, or covid-19 vaccine before; - inoculated with any vaccine within no less than 14 days of the study; - axillary temperature ≤37.0℃