H7N9, a novel avian influenza A virus that causes human infections emerged in February, 2013 in Anhui and Shanghai, China. The epidemic quickly spread to Zhejiang, Jiangsu and other neighbor provinces. As of May 30th, 2013, WHO had reported 132 cases, 37 (28%) of which died. Aiming at such serious outbreak of epidemic, we retrospectively analyzed its etiology, epidemiology, clinical characteristics, treatment, prevention and control based on data and evidence. Experience and evidence of the risk surveillance and management of such a novel anthropozoonosis lacks in China, or even lacks around the world. Quick and accurate identification of the rules and of the variation and transmission of avian influenza virus becomes a key to prevention, control and treatment. According to current best available evidence around the world, Chinese medicine and biomedicine should be put in to parallel use. Only realizing evidence-based decision making can we effectively prevent and control the epidemic, treat patients, and reduce the loss.
Objective To investigate specific changes of T cell repertoire in convalescent patients infected by influenza A (H7N9) virus. Methods Peripheral blood samples from 8 convalescent patients infected by H7N9 virus and 10 healthy donors were collected. After extracting whole DNA from these samples, arm-PCR were performed and the products were submitted to Illumina HiSeq2000 platform to produce deep sequencing data of the nucleotide sequences of complementary determining region 3 of T cell receptor β chain (TRB). Differences were compared in TRB diversity and V-D-J gene usage and similarities of sequences between the patients and the healthy donors. Results Frequency of V-D-J gene usage was different between the H7N9 patient group and the healthy group, such as TRBV30, TRBV27, and TRBV18 (Student's t test, P < 05). Main component analysis showed V-J pairing pattern was significantly different between two groups, which may have potential in identifying patients from healthy people. A considerable number of shared CDR3s were found in patient-patient pairs and normal-normal pairs, while seldom were found in patient-normal pairs. The similarity between patients was also confirmed by overlap distance analysis. Indexes for assessing diversity of immune repertoires, Shannon-Weiner index and Simpson index, were both lower in the patients (Student's t test, P < 05), suggesting that the immune system of the patients had not recovered 6 months after H7N9 infection. Compared with the healthy donors, the number of hyper-expression clones increased in the patient group, and some of them showed similarity among patients. Conclusions TRB repertoires are less diverse in patients with increased hyper-expressed clones and identifiable V-J usage pattern, which is identifiable from normal population. These results suggest that there are H7N9-specific changes in TRB repertoires of H7N9 infected patients in convalescent phase, which have potential implication in diagnosis and therapeutic T cell development.
Objective Since the first case of avian influenza A (H7N9) virus infection in humans identified in Suining, Sichuan province on January 25th, 2017, there were other five severely ill patients confirmed in the following 3 weeks. It is urgent to find out the common clinical characters of these patients, so that to make sure the optimal ways for early diagnosis and treatment for H7N9 virus infection in community hospitals or primary hospitals as soon as possible. Methods The early symptoms, the data of early laboratory findings, the early imaging study, the early process of diagnosis and treatment of these six patients were collected and analyzed. Results All six patients had high fever, dry cough, hypocalcemia, and hypophosphatemia, with advanced CT image lesions manifested as consolidation and ground-grass opacity in bilateral lower lung lobes. Some patients had typically leukopenia, lymphopenia, thrombocytopenia. And most of them had a history of direct exposure to live poultry before complaining of flu-like syndromes. However, the flu can not be effectively controlled by routine anti-infection. Conclusion The human infection with H7N9 virus can be early identified by combining the epidemiology of live poultry exposure, the symptoms of high fever, dry cough, dramatical leukopenia, lymphopenia, thrombocytopenia, the typical CT image, and the rapidly worsen clinical condition.
ObjectiveTo evaluate the effect of low-to-moderate doses of corticosteroids on human infections with avian influenza A (H7N9) virus, and explore when to initiate the treatment of corticosteroids and the duration of corticosteroids administration.MethodsThe study collected clinical data of 8 cases with avian influenza A (H7N9) virus infection admitted from January 25, 2017 to May 12, 2017. The final analysis included 5 severe patients who had received adjuvant corticosteroid treatment. The variation curves of WBC, CRP, PCT, CK, HBDH, LDH, temperature, ratio of SpO2/FiO2 were depicted and analyzed. The progress of clinical improvements, deterioration and prognosis were observed and discussed.ResultsThere were 1 female and 4 males in the 5 included patients with a median age of 58.0 years, among them 3 survived. The median time of illness onset to hospitalization and diagnosis confirmed were 4 days and 8 days respectively; the median duration of hospitalization to admission to infective ICU were 3 days. The first course of adjuvant corticosteroid treatment was initiated 11 days (median) after admission with a duration of 4 days (median), during which, the serum levels of HBDH and LDH decreased remarkably except the patient 3, and the oxygenation (SpO2/FiO2) improved except the patient 3. The second course of systemic administration of corticosteroid was given at a median of 26.5 days after admission with a duration of 9 days (median), during which, the patients survived with improved oxygenation (SpO2/FiO2), and weaned from mechanical ventilation.ConclusionsFor patients suffered severe human infection with avian influenza A (H7N9) virus, low-to-moderate doses of corticosteroids may decrease the level of inflammation, regulate the aberrant immune response, improve the oxygenation, make an early unassisted breathing. And corticosteroids treatment can be initiated at the time of disease deterioration, after/at the peak inflammatory response, and within 10-14 days of ARDS. Also, the adjuvant corticosteroids may be administered when oxygenation is dificult to be improved by other ways, or dificult to be liberated from mechanical ventilation, suffering severe septic shock, and refractory fever. And the duration of corticosteroids may be prolonged to 10-14 days, or until the higher level of HBDH and LDH decreased again.
ObjectiveTo analyze the clinical and epidemiological characteristics of hospitalized avian influenza A (H7N9) virus infections in Hunan province from 2013 to 2017, and provide evidences for control, diagnosis and treatment of this disease.MethodsNinety-one hospitalized patients were confirmed with H7N9 infection in Hunan. Excluding 2 patients less than 18 years old and 10 with missing data, 79 patients with H7N9 infection were analyzed.ResultsMost confirmed cases were affected in the second and fifth epidemic wave and number of patients in the fifth wave was more than the sum in prior 4 waves. Epidemiological characteristics, clinical symptoms and case fatality did not change significantly. Administration of antiviral drugs was more active in the fifth wave [from illness onset to antiviral drug: (6.3±2.4)d vs. (7.6±2.4)d, P=0.047]. Multiple logistic regression analysis showed that shock (OR=4.683, 95%CI 1.136–19.301, P=0.033) was the independent risk factor of H7N9 infections. There were no significant differences in case fatality among group oseltamivir, group oseltamivir+peramivir, and group peramivir.ConclusionsPatients with avian influenza A (H7N9) increased in the fifth wave but clinical characteristics changed little. Antiviral treatment should be more active. Shock is an independent risk factor of H7N9 infections. Oseltamivir-peramivir biotherapy can not reduce case fatality compared with oseltamivir or peramivir monotherapy.