Investigation and emergency management of a nosocomial infection outbreak of Omicron BA.5.1.3 strain of SARS-CoV-2

Objective: To investigate a nosocomial infection outbreak of Omicron BA.5.1.3 strain of SARS-CoV-2, and to analyze the transmission mode of Omicron BA.5.1.3 strain in hospitals, in order to evaluate the effect of nosocomial infection control and provide a basis for the epidemic prevention and control of this strain in hospitals. Methods: The onsite epidemiological methods were used to investigate the confirmed cases and their close contacts, and the prevention and control measures of nosocomial infection caused by this outbreak were studied. Results: The outbreak time of nosocomial infection was from August 4 to August 8, and the incubation period was 1-5 days, with an average incubation period of 3.0 days. The first confirmed case was a 53-year-old woman who received three doses of COVID-19 vaccine and accompanied the family of the patient in the hospital. She had traveled to a high-risk area three days before onset of the disease, and the virus type was Omicron BA.5.1.3 strain. The outbreak area was two adjacent wards of the hospital, and the incidence rates of inpatients in the two wards were 66.67% (2/3) and 33.33% (1/3), respectively. A total of 967 people were affected, including 1 imported case, 4 hospitalized cases (3 hospitalized patients and 1 nurse), 537 close contacts and 425 secondary close contacts. On August 5, the city's disease control and prevention telephone notified the first confirmed COVID-19 case. Within 0.5 hours, the ward where the case was located was sealed and static management was carried out. Measures such as district grid management, nucleic acid test in the whole hospital and in-hospital flow control were initiated. Environmental sampling, whole environment disinfection and telephone flow adjustment of case 1 were completed within 4 hours. Close contacts, secondary close contacts sampling and control were completed within 24 hours. We paid attention to the dynamics of close contacts and secondary close contacts, as if whose nucleic acid was positive, further measures could be taken to eliminate the risks. The hospital returned to normal management on August 13. Conclusion: The novel coronavirus BA.5.1.3 strain shows strong pathogenicity, short incubation period, causing overall mild disease. Timely and comprehensive prevention and control measures were the key meathods to nosocomial infection control.

Characteristics and outcomes of patients with COVID-19 in Hainan, South China.

ABSTRACT: As an international tourist center, Hainan province includes both imported and local COVID-19 cases. This study aimed to investigate the clinical characteristics and outcomes of COVID-19 patients in Hainan, China.COVID-19 patients hospitalized in Hainan affiliated Hospital of Hainan Medical University in January to March 2020 were retrospectively assessed. Routine blood tests, blood gas analyses, and computed tomography imaging were performed within 24 hours. Virus nucleic acid was detected every other day. The patients were divided into local resident and traveler groups, and differences in clinical data as well as leukocyte, lymphocyte, and neutrophil levels were analyzed.A total of 70 patients aged 51.23 ±â€Š13.54 years were assessed, including 16 local residents and 54 travelers. Of these, 55 cases (78.6%) had fever, 47 (67.1%) had cough and sputum, and 9 (12.9%) had chest dyspnea; 60 and 10 cases were mild/common and severe/critical, respectively. Sex, basic diseases, smoking history and drinking history, Charlson Comorbidity Index, symptoms, time of onset to admission, clinical severity, white blood cell count, lymphocyte count, neutrophil count, oxygen inhalation, mechanical ventilation, glucocorticoid therapy, treatment, admission to ICU, hospital stay, and mortality were similar between the 2 groups.The warm and humid climate of Hainan does not seem to significantly affect patient features and outcomes from COVID-19. Unnecessary travel to tourist areas should be avoided.

Early chest CT features of patients with 2019 novel coronavirus (COVID-19) pneumonia: relationship to diagnosis and prognosis.

OBJECTIVE: To determine the consistency between CT findings and real-time reverse transcription-polymerase chain reaction (RT-PCR) and to investigate the relationship between CT features and clinical prognosis in COVID-19. METHODS: The clinical manifestations, laboratory parameters, and CT imaging findings were analyzed in 34 COVID-19 patients, confirmed by RT-PCR from January 20 to February 4 in Hainan Province. CT scores were compared between the discharged patients and the ICU patients. RESULTS: Fever (85%) and cough (79%) were most commonly seen. Ten (29%) patients demonstrated negative results on their first RT-PCR. Of the 34 (65%) patients, 22 showed pure ground-glass opacity. Of the 34 (50%) patients, 17 had five lobes of lung involvement, while the 23 (68%) patients had lower lobe involvement. The lesions of 24 (71%) patients were distributed mainly in the subpleural area. The initial CT lesions of ICU patients were distributed in both the subpleural area and centro-parenchyma (80%), and the lesions were scattered. Sixty percent of ICU patients had five lobes involved, while this was seen in only 25% of the discharged patients. The lesions of discharged patients were mainly in the subpleural area (75%). Of the discharged patients, 62.5% showed pure ground-glass opacities; 80% of the ICU patients were in the progressive stage, and 75% of the discharged patients were at an early stage. CT scores of the ICU patients were significantly higher than those of the discharged patients. CONCLUSION: Chest CT plays a crucial role in the early diagnosis of COVID-19, particularly for those patients with a negative RT-PCR. The initial features in CT may be associated with prognosis. KEY POINTS: • Chest CT is valuable for the early diagnosis of COVID-19, particularly for those patients with a negative RT-PCR. • The early CT findings of COVID-19 in ICU patients differed from those of discharged patients.