Objective:To investigate the clinical characteristics and vaccination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in maintenance hemodialysis (MHD) patients.Methods:It was a cross-sectional survey. Through wechat questionnaire star mode, the status of SARS-CoV-2 infection, clinical manifestation after infection and vaccination of MHD patients in Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine between December 8, 2022 and January 12, 2023 were retrospectively collected during the period that SARS-CoV-2 infection was managed with measures against class B infectious diseases. The patients were grouped according to whether they were infected with SARS-CoV-2 and whether they were complicated with pneumonia after infection during the study period. Logistic regression analysis was used to analyze the risk factors of SARS-CoV-2 infection combined with pneumonia or persistent symptoms after SARS-CoV-2 turning negative.Results:A total of 241 questionnaires were issued, and 223 valid questionnaires were returned, of which 175 patients (78.5%) were infected with SARS-CoV-2 during the study period. The time of negative conversion of antigen or nucleic acid after SARS-CoV-2 infection was 10 (7,14) days. Asymptomatic infections accounted for 10.3% (18/175). Symptomatic infections accounted for 89.7% (157/175), and the top five most frequent symptoms were cough (70.1%, 110/157), fever (64.3%, 101/157), pharyngeal pain (35.0%, 55/157), muscle pain (28.7%, 45/157), and nasal obstruction (21.0%, 33/157). Pneumonia was reported in 54.3% (95/175) of infected patients. There were no statistically significant differences in age, gender distribution, proportion of diabetes mellitus, and proportion of history of tumors between SARS-CoV-2-infected and uninfected patients (all P>0.05). Compared with the non-pneumonia group, the proportions of dyspnea (12.6% vs. 1.3%, χ2=8.181, P=0.004) and chest tightness (23.2% vs. 10.0%, χ2=5.293, P=0.021) in the pneumonia group were both higher. There were no significant differences in age, gender distribution, time of negative SARS-CoV-2 transition, number of symptoms and SARS-CoV-2 vaccination rate,and proportions of diabetes mellitus and tumors between the pneumonia group and the non-pneumonia group (all P>0.05). There were 48.6% (85/175) infected patients having long-lasting clinical symptoms after SARS-CoV-2 turning negative. Logistic regression analysis results showed that diarrhea was an independent influencing factor of pneumonia in MHD patients infected with SARS-CoV-2 [ OR (95% CI)=6.323 (1.061-37.682), P=0.043]. The number of symptoms at onset [ OR (95% CI)=1.571 (1.318-1.873), P<0.001] and history of tumors [ OR (95% CI)=0.206 (0.054-0.777), P=0.020] were independent influencing factors of long-lasting clinical symptoms. The SARS-CoV-2 vaccination rate was 7.2% (16/223) in MHD patients due to safety concerns (81.2%, 164/202). Conclusions:MHD patients are SARS-CoV-2-susceptible population. The clinical symptoms after infection are diverse, heterogeneous, and the proportion of complicated pneumonia is high. Diarrhea is an independent influencing factor of pneumonia in SARS-CoV-2-infected MHD patients. Nearly half of patients experience long-lasting clinical symptoms after SARS-CoV-2 turning negative. The low rate of vaccination in the MHD population necessitates increased awareness about the safety and efficacy of SARS-CoV-2 vaccine.