Family Cluster Of Infection Research Articles

The Clinical Characteristics of Fever-Ward Pediatric Patients with a Definite Epidemiological History During the Early COVID-19 Epidemic Period.

ObjectiveThe number of children presenting with coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 infection is increasing, and we aimed to assess the clinical characteristics of pediatric patients with a definite epidemiological history during the early COVID-19 epidemic.MethodsRetrospective analysis was performed on the clinical data of children admitted to the fever ward of Xiangyang Central Hospital in Hubei province between January 1, 2020 and March 17, 2020. According to definite epidemiological history, patients with SARS-CoV-2 nucleic acid test (NAT) positive detection were grouped as confirmed cases, and patients with two consecutive negative NATs were grouped as suspected cases. We compared the clinical characteristics of the two groups.ResultsA total of 47 (47/127, 37%) cases had a definite epidemiological history, of which 32 (68.1%) were suspected, with a median age of 5.5 years (interquartile range [IQR]: 0.7–10.3), and 15 (31.9%) were confirmed, with a median age of 9 years (IQR: 4–14). Statistically significant differences in age, family cluster of infection, and numbers of patients with clinical symptoms and fever (P<0.05) were found between the two groups, but no statistically significant differences in leucocyte and lymphocyte counts were observed (P>0.05). Significant differences were found in the computed tomography (CT) manifestation of ground glass opacity (GGO) between the two groups (P<0.05).ConclusionChildren of older age and from family clusters of infection were more easily diagnosed as having COVID-19. GGO changes on chest CT was more likely in confirmed cases. Although obvious clinical manifestations increase our awareness of COVID-19, children without manifestations of fever or cough should not be ignored as they may be asymptomatic carriers.

The fifth influenza A(H7N9) epidemic: A family cluster of infection in Suzhou city of China, 2016

ObjectiveInfluenza A(H7N9) virus is known for its high pathogenicity in human. A family cluster of influenza A(H7N9) virus infection was identified in Suzhou, China. This study aimed to investigate the possibility of human-to-human transmission of the virus and examine the virologic features of this family cluster. MethodsThe clinical and epidemiologic data of two patients in the family cluster of influenza A(H7N9) virus infection were collected. Viral RNA in samples derived from the two patients, their close contacts, and the environments with likely influenza A(H7N9) virus transmission were tested by real-time reverse transcriptase polymerase chain reaction (rRT-PCR) assay. Hemagglutination inhibition (HI) assay was used to detect virus-specific antibodies. Genetic sequencing and phylogenetic analysis were also performed. ResultsThe index patient (Case 1), a 66-year old man, was virologically diagnosed with influenza A(H7N9) virus infection 12days after experiencing influenza-like symptoms, then died of multi-organ failure. His 39-year old daughter (Case 2), denying any other exposure to influenza A(H7N9) virus, became infected with influenza A(H7N9) virus following taking care of her father during his illness. Sequencing viral genomes isolated from the two patients showed nearly identical nucleotide sequence, and genetically resembled the viral genome isolated from a chicken in the wet market where the index patient once visited. All three influenza A(H7N9) viruses shared S138A, G186V, Q226L mutations in HA (H3) protein and a single basic amino acid (PEIPKGR↓G) at the cleavage site. ConclusionsHuman-to-human transmission of influenza A(H7N9) virus most likely occurred in this household. The three-amino-acid mutations in HA protein were discovered in this study, which might have increased the binding affinity of influenza A(H7N9) virus to the receptor on trachea epithelial cells to facilitate viral transmission among humans.

A Family Cluster of Infections by a Newly Recognized Bunyavirus in Eastern China, 2007: Further Evidence of Person-to-Person Transmission

Seven persons in one family living in eastern China developed fever and thrombocytopenia during May 2007, but the initial investigation failed to identify an infectious etiology. In December 2009, a novel bunyavirus (designated severe fever with thrombocytopenia syndrome bunyavirus [SFTSV]) was identified as the cause of illness in patients with similar clinical manifestations in China. We reexamined this family cluster for SFTSV infection. We analyzed epidemiological and clinical data for the index patient and 6 secondary patients. We tested stored blood specimens from the 6 secondary patients using real time reverse transcription polymerase chain reaction (RT-PCR), viral culture, genetic sequencing, micro-neutralization assay (MNA), and indirect immunofluorescence assay (IFA). An 80-year-old woman with fever, leucopenia, and thrombocytopenia died on 27 April 2007. Between 3 and 7 May 2007, another 6 patients from her family were admitted to a local county hospital with fever and other similar symptoms. Serum specimens collected in 2007 from these 6 patients were positive for SFTS viral RNA through RT-PCR and for antibody to SFTSV through MNA and IFA. SFTSV was isolated from 1 preserved serum specimen. The only shared characteristic between secondary patients was personal contact with the index patient; none reported exposure to suspected animals or vectors. Clinical and laboratory evidence confirmed that the patients of fever and thrombocytopenia occurring in a family cluster in eastern China in 2007 were caused by a newly recognized bunyavirus, SFTSV. Epidemiological investigation strongly suggests that infection of secondary patients was transmitted to family members by personal contact.