Laboratory-confirmed Human Cases Research Articles

Global concerns about camel flu: outbreak, etiology, genomic structure, transmission, symptoms, diagnostic tests, prevention, and treatment - correspondence.

Global concerns about camel flu: outbreak, etiology, genomic structure, transmission, symptoms, diagnostic tests, prevention, and treatment - correspondence.

Sindbis virus outbreak and evidence for geographical expansion in Finland, 2021.

Sindbis virus (SINV) caused a large outbreak in Finland in 2021 with 566 laboratory-confirmed human cases and a notable geographical expansion. Compared with the last large outbreak in 2002, incidence was higher in several hospital districts but lower in traditionally endemic locations in eastern parts of the country. A high incidence is also expected in 2022. Awareness of SINV should be raised in Finland to increase recognition of the disease and prevent transmission through the promotion of control measures.

Human brucellosis epidemiological characteristics in Qiqihar, Heilongjiang, 2004–2019

Objective To analyze the epidemiological characteristics of human brucellosis in Qiqihar of Heilongjiang province from 2004–2019, and provide scientific evidence for the development of brucellosis prevention and control strategy. Methods The time, geographical and population distributions of laboratory confirmed brucellosis case were analyzed with descriptive epidemiological method. Results A total of 25 999 laboratory-confirmed human brucellosis cases, without death, were reported online in Qiqihar from 2004 to 2019. The average annual incidence rate was 29.50/100 000, 11.17 times higher than national average (2.64/100 000) during the same period. The incidence of human brucellosis in Qiqihar was at a high level. There were two peaks in 2005 and 2012. The incidence increased significantly in 2019, with incidence rates of 23.56/100 000, the highest incidence was during March–July. The cases were aged from 9 months to 92 years. Most cases were middle-aged, men, farmers and herdsmen. The spread area of the disease was wide, the cases were reported in 94.60% of townships and 57.70% of all villages in 16 counties in 2012. In the non-occupational group, the proportions of the jobless or unemployed, students, workers, children outside child care settings were relatively high. The proportion of the jobless or employed was in increase. Conclusion The incidence of brucellosis in Qiqihar was much higher than the national level, Animal husbandry departments should strengthen the prevention and control of brucellosis. To reduce the incidence of human brucellosis, the quarantine, immunization and culling of livestock should be further strengthened, and health education and promotion should be implemented.

Low SARS-CoV-2 Seroprevalence and No Active Infections among Dogs and Cats in Animal Shelters with Laboratory-Confirmed COVID-19 Human Cases among Employees.

Simple SummaryWe investigated dogs and cats living in four animal shelters in the United States that had been exposed to people with COVID-19 in the shelters. Our objective was to understand if the animals were infected with SARS-CoV-2, the virus that causes COVID-19. We found that out of the 96 dogs and cats that we sampled, none had active SARS-CoV-2 infections and only one dog had detectable antibodies to SARS-CoV-2, meaning that it had been exposed to the virus but was not actively infected. This suggests that the risk of humans spreading SARS-CoV-2 to dogs and cats in animal shelter settings is probably low.Human-to-animal and animal-to-animal transmission of SARS-CoV-2 has been documented; however, investigations into SARS-CoV-2 transmission in congregate animal settings are lacking. We investigated four animal shelters in the United States that had identified animals with exposure to shelter employees with laboratory-confirmed COVID-19. Of the 96 cats and dogs with specimens collected, only one dog had detectable SARS-CoV-2 neutralizing antibodies; no animal specimens had detectable viral RNA. These data indicate a low probability of human-to-animal transmission events in cats and dogs in shelter settings with early implementation of infection prevention interventions.

Duck-origin H5N6 avian influenza viruses induce different pathogenic and inflammatory effects in mice.

Since 2013, H5N6 highly pathogenic avian influenza viruses have caused considerable economic losses in the poultry industry and have caused 24 laboratory-confirmed human cases. In this study, we isolated nine (B1-B9) H5N6 viruses from healthy ducks in Guangdong Province, Southern China from December 2018 to April 2019. Phylogenetic analysis revealed that B1, B2, B3, B4, B5, B7, B8, and B9 clustered into the G1.1 genotype and shared high sequence similarity with human H5N6 isolates from Southern China in 2017 and 2018. Meanwhile, B6 clustered into the G1.1.9 genotype. The hemagglutinin (HA), neuraminidase (NA) and nonstructural protein (NS) gene segments of B6 were closely related to the human H5N6 isolates, while the other genomic segments were closely related to H5N6 viruses isolated from waterfowl in Southern China. Compared to B7, B6 had higher pathogenicity and induced stronger inflammatory responses in mice. B6 carried a full-length PB1-F2 protein (90 aa), while the rest carried an 11-amino acid C-terminal-truncated PB1-F2. The PB1-F2 protein may increase the virulence of B6 compared to that of B7. Our findings provide insight into the pathogenic mechanisms of H5N6 viruses in mammals and emphasize the need for continued surveillance of circulating H5N6 viruses in ducks.

Public health needs and challenges in influenza and dengue vaccines–Implications from epidemiological findings

Background: The incidence and mortality rates of influenza and dengue have been high in most Asian countries. Vaccination is the one of the most important and successful public health measures in controlling many infectious diseases such as poliomyelitis, measles, and Japanese encephalitis. However, the etiological agents of these two diseases are RNA viruses involving different subtypes/serotypes with dynamic changes each year, posing greater challenges in future years. Methods and materials: Field epidemiology during outbreak periods provides the best chance in fully understanding dynamic changes of the studied virus and evaluating the impact of mismatched human influenza viruses. On the other hand, incidence and hospitalization rates, case fatality rates and seroepidemiological study of dengue are important in assessing public health needs and community effectiveness of vaccine as well as in finding target population to receive dengue vaccine. Results: We found that the higher isolation rate of seasonal influenza A (H3N2) and the circulating vaccine-mismatched human influenza viruses, the greater monthly P&I mortality in elderly, using a negative binomial model. Moreover, those years with high excess P&I mortality had the circulating virus strains with a lower amino acid identity percentages of HA1 protein with the vaccine strains. During 2009 pandemic influenza, one unique adaptive mutant at E374K of HA2 in A (H1N1/09) viruses evolved through the epidemic, emerged as a dominant strain at post-peak period, extended in areas with high population densities before mass immunization, persisted till ten months post-nationwide vaccination, and were finally fixed as herd immunity developed. Recently, different tetravalent dengue vaccines providing immunity against all four serotypes of dengue virus (DENV) have been developed to avoid antibody-dependent enhancement (ADE) from secondary DENV infection. The initial clinical trials in many cities of dengue-endemic countries did reduce the incidence and hospitalization rates of dengue. Conclusion: Weekly monitoring excess P&I mortality and evaluating laboratory-confirmed human influenza cases with/without receiving flu vaccines plus serological tests on antigenic variation can assure public health effectiveness of influenza vaccines. Once novel influenza virus emerges with worldwide spread, virological surveillance in high population-density areas can assess the virus with high epidemic potential. Furthermore, more immuno-epidemiological studies are needed for dengue in different settings.

Global burden of acute lower respiratory infection associated with human metapneumovirus in children under 5 years in 2018: a systematic review and modelling study

SummaryBackgroundHuman metapneumovirus is a common virus associated with acute lower respiratory infections (ALRIs) in children. No global burden estimates are available for ALRIs associated with human metapneumovirus in children, and no licensed vaccines or drugs exist for human metapneumovirus infections. We aimed to estimate the age-stratified human metapneumovirus-associated ALRI global incidence, hospital admissions, and mortality burden in children younger than 5 years.MethodsWe estimated the global burden of human metapneumovirus-associated ALRIs in children younger than 5 years from a systematic review of 119 studies published between Jan 1, 2001, and Dec 31, 2019, and a further 40 high quality unpublished studies. We assessed risk of bias using a modified Newcastle-Ottawa Scale. We estimated incidence, hospital admission rates, and in-hospital case-fatality ratios (hCFRs) of human metapneumovirus-associated ALRI using a generalised linear mixed model. We applied incidence and hospital admission rates of human metapneumovirus–associated ALRI to population estimates to yield the morbidity burden estimates by age bands and World Bank income levels. We also estimated human metapneumovirus-associated ALRI in-hospital deaths and overall human metapneumovirus-associated ALRI deaths (both in-hospital and non-hospital deaths). Additionally, we estimated human metapneumovirus-attributable ALRI cases, hospital admissions, and deaths by combining human metapneumovirus-associated burden estimates and attributable fractions of human metapneumovirus in laboratory-confirmed human metapneumovirus cases and deaths.FindingsIn 2018, among children younger than 5 years globally, there were an estimated 14·2 million human metapneumovirus-associated ALRI cases (uncertainty range [UR] 10·2 million to 20·1 million), 643 000 human metapneumovirus-associated hospital admissions (UR 425 000 to 977 000), 7700 human metapneumovirus-associated in-hospital deaths (2600 to 48 800), and 16 100 overall (hospital and community) human metapneumovirus-associated ALRI deaths (5700 to 88 000). An estimated 11·1 million ALRI cases (UR 8·0 million to 15·7 million), 502 000 ALRI hospital admissions (UR 332 000 to 762 000), and 11 300 ALRI deaths (4000 to 61 600) could be causally attributed to human metapneumovirus in 2018. Around 58% of the hospital admissions were in infants under 12 months, and 64% of in-hospital deaths occurred in infants younger than 6 months, of which 79% occurred in low-income and lower-middle-income countries.InterpretationInfants younger than 1 year have disproportionately high risks of severe human metapneumovirus infections across all World Bank income regions and all child mortality settings, similar to respiratory syncytial virus and influenza virus. Infants younger than 6 months in low-income and lower-middle-income countries are at greater risk of death from human metapneumovirus-associated ALRI than older children and those in upper-middle-income and high-income countries. Our mortality estimates demonstrate the importance of intervention strategies for infants across all settings, and warrant continued efforts to improve the outcome of human metapneumovirus-associated ALRI among young infants in low-income and lower-middle-income countries.FundingBill & Melinda Gates Foundation.

Epidemiology of human rabies in South Africa, 2008 - 2018.

Human rabies cases continue to be reported annually in South Africa (SA). Previous investigations have shown the association between the occurrence of human rabies cases and dog rabies cases in the country. To describe the epidemiology of laboratory-confirmed human rabies cases in SA for the period 2008 - 2018. A retrospective document review of laboratory-confirmed human rabies cases for the period 2008 - 2018 was performed using a case register and related documentation available from the National Institute for Communicable Diseases. A total of 105 human rabies cases were laboratory confirmed from 2008 to 2018, with cases reported from all the provinces of SA except the Western Cape. Children and adolescents were most affected by the disease during the study period. In almost half of the cases, medical intervention was not sought after exposure. When victims did seek healthcare, deviations from post-exposure prophylaxis protocols were reported in some cases. The epidemiological trends of human rabies cases reported in SA for the period 2008 - 2018 remained largely the same as in previous reports. Dog-mediated rabies remains the main source of human rabies in SA.

Spatial and temporal clusters of avian influenza a (H7N9) virus in humans across five epidemics in mainland China: an epidemiological study of laboratory-confirmed cases

BackgroundAvian influenza A (H7N9) virus was first reported in mainland China in 2013, and alarming in 2016–17 due to the surge across a wide geographic area. Our study aimed to identify and explore the spatial and temporal variation across five epidemics to reinforce the epidemic prevention and control.MethodsWe collected spatial and temporal information about all laboratory-confirmed human cases of A (H7N9) virus infection reported in mainland China covering 2013–17 from the open source. The autocorrelation analysis and intensity of cases were used to analyse the spatial cluster while circular distribution method was used to analyse the temporal cluster.ResultsAcross the five epidemics, a total of 1553 laboratory-confirmed human cases with A (H7N9) virus were reported in mainland China. The global Moran’s I index values of five epidemic were 0.610, 0.132, 0.308, 0.306, 0.336 respectively, among which the differences were statistically significant. The highest intensity was present in the Yangtze River Delta region and the Pearl River Delta region, and the range enlarged from the east of China to inner provinces and even the west of China across the five epidemics. The temporal clusters of the five epidemics were statistically significant, and the peak period was from the end of January to April with the first and the fifth epidemic later than the mean peak period.ConclusionsSpatial and temporal clusters of avian influenza A (H7N9) virus in humans are obvious, moreover the regions existing clusters may enlarge across the five epidemics. Yangtze River Delta region and the Pearl River Delta region have the spatial cluster and the peak period is from January to April. The government should facilitate the tangible improvement for the epidemic preparedness according to the characteristics of spatial and temporal clusters of patients with avian influenza A (H7N9) virus.

Human rabies in China: evidence-based suggestions for improved case detection and data gathering

BackgroundChina still suffers heavily from rabies, although reported human cases continue to decrease year over year. There are far fewer laboratory-confirmed human cases than clinically diagnosed cases, which is a big problem that needs to be addressed. In this report, we summarize analyses of all specimens from human cases tested in our laboratory over the past 15 years, in order to promote laboratory diagnosis of rabies.MethodsFrom 2005 to 2019, a total of 271 samples from 164 suspected rabies cases were collected from local hospitals by the local Centers for Disease Control and Prevention (CDCs) in China. Saliva, cerebrospinal fluid (CSF), serum (blood) and urine were collected for ante-mortem diagnosis, and brain tissue, neck skin tissue and cornea were collected for post-mortem diagnosis. All of the specimens were tested by reverse transcription-polymerase chain reaction (RT-PCR), and brain tissues were also tested using fluorescent antibody test (FAT). The number of positive test results obtained using different fluids or tissues, and at different stages of the disease, were compared using a chi-square test and a more effective sampling program is recommended.ResultsAs the national reference laboratory for rabies surveillance in China, our laboratory has tested 271 samples from 164 suspected rabies cases collected by local CDCs since 2005. We found that saliva gave the highest number of positive test results (32%), compared with CSF and other fluids. We also found that serum or blood specimens collected in the last 3 days of life can test positive by RT-PCR.ConclusionsSerum or blood samples collected in the last 3 days of a patient’s life can be used to measure viral RNA, which means that serum samples, as well as saliva and CSF, can be used to detect viral RNA for anti-mortem diagnosis of rabies. Because of our findings, we have modified our “National Surveillance Project for Human Rabies”, by adding the collection and testing of serum samples from the end of the survival period. This will improve our national surveillance and laboratory diagnosis of human rabies.

Live poultry market closure and avian influenza A (H7N9) infection in cities of China, 2013\u20132017: an ecological study

BackgroundPrevious studies have proven that the closure of live poultry markets (LPMs) was an effective intervention to reduce human risk of avian influenza A (H7N9) infection, but evidence is limited on the impact of scale and duration of LPMs closure on the transmission of H7N9.MethodFive cities (i.e., Shanghai, Suzhou, Shenzhen, Guangzhou and Hangzhou) with the largest number of H7N9 cases in mainland China from 2013 to 2017 were selected in this study. Data on laboratory-confirmed H7N9 human cases in those five cities were obtained from the Chinese National Influenza Centre. The detailed information of LPMs closure (i.e., area and duration) was obtained from the Ministry of Agriculture. We used a generalized linear model with a Poisson link to estimate the effect of LPMs closure, reported as relative risk reduction (RRR). We used classification and regression trees (CARTs) model to select and quantify the dominant factor of H7N9 infection.ResultsAll five cities implemented the LPMs closure, and the risk of H7N9 infection decreased significantly after LPMs closure with RRR ranging from 0.80 to 0.93. Respectively, a long-term LPMs closure for 10–13 weeks elicited a sustained and highly significant risk reduction of H7N9 infection (RRR = 0.98). Short-time LPMs closure with 2 weeks in every epidemic did not reduce the risk of H7N9 infection (p > 0.05). Partially closed LPMs in some suburbs contributed only 35% for reduction rate (RRR = 0.35). Shenzhen implemented partial closure for first 3 epidemics (p > 0.05) and all closure in the latest 2 epidemic waves (RRR = 0.64).ConclusionOur findings suggest that LPMs all closure in whole city can be a highly effective measure comparing with partial closure (i.e. only urban closure, suburb and rural remain open). Extend the duration of closure and consider permanently closing the LPMs will help improve the control effect. The effect of LPMs closure seems greater than that of meteorology on H7N9 transmission.

Analysis of temporal trends of human brucellosis between 2013 and 2018 in Yazd Province, Iran to predict future trends in incidence: A time-series study using ARIMA model

Objective: To determine the temporal patterns of cumulative incidence of brucellosis using autoregressive integrated moving average models. Methods: This cross-sectional study employed yearly and monthly data of 1 117 laboratory-confirmed human brucellosis cases from January 2013 to December 2018 using the Yazd brucellosis national surveillance system. The monthly incidences constructed a timeseries model. The trend of cumulative incidence was perceived by tracing a line plot, which displayed a seasonal trend with periodicity. Thus, the ARIMA models were selected. Thereafter, Akaike information criteria (AIC) and Bayesian information criterion (BIC) values among different models indicated a preferable model from models which were expanded by diverse lags [(3, 0, 3), (2, 0, 3), (3, 0, 2), (4, 0, 3) and (3, 0, 4)]. Then, the achieved ARIMA model was applied to the forecasting cumulative incidence of monthly brucellosis incidences. All analyses were performed using Stata, version 11.2. Results: For the ARIMA (3, 0, 4) model, MAPE value was 56.20% with standard error 0.009-0.016, and white noise diagnostic check (Q=19.79, P=0.975) for the residuals of the selected model showed that the data were completely modelled. The monthly incidences that were fitted by the ARIMA (3, 0, 4) model, with AIC (25.7) and BIC (43.35) with a similar pattern of actual cases from 2013 to 2018 and forecasting incidences from January 2019 to December 2019 were, respectively, 0.50, 0.44, 0.45, 0.49, 0.55, 0.58, 0.56, 0.51, 0.46, 0.44, 0.45 and 0.49 per 100 000 people. Conclusions: In summary, the study showed that the ARIMA (3, 0, 4) model can be applied to forecast human brucellosis patterns in Yazd province, supplementing present surveillance systems, and may be better for health policy-makers and planners.

Antigen Capture Enzyme-Linked Immunosorbent Assay for Detecting Middle East Respiratory Syndrome Coronavirus in Humans.

The Middle East respiratory syndrome (MERS) is the second novel zoonotic disease infecting humans caused by coronavirus (CoV) in this century. To date, more than 2200 laboratory-confirmed human cases have been identified in 27 countries, and more than 800 MERS-CoV associated deaths have been reported since its outbreak in 2012. Rapid laboratory diagnosis of MERS-CoV is the key to successful containment and prevention of the spread of infection. Though the gold standard for diagnosing MERS-CoV infection in humans is still nucleic acid amplification test (NAAT) of the up-E region, an antigen capture enzyme-linked immunosorbent assay (ELISA) could also be of use for early diagnosis in less developed locations. In the present method, a step-by-step guide to perform a MERS-CoV nucleocapsid protein (NP) capture ELISA using two NP-specific monoclonal antibodies is provided for readers to develop their in-house workflow or diagnostic kit for clinical use and for mass-screening project of animals (e.g., dromedaries and bats) to better understand the spread and evolution of the virus.

A human case of spotted fever caused by Rickettsia parkeri strain Atlantic rainforest and its association to the tick Amblyomma ovale

BackgroundRickettsia parkeri strain Atlantic rainforest has emerged in Brazil during the last 10 years, with three laboratory-confirmed human cases. While these cases were epidemiologically associated with the tick Amblyomma ovale, in none of them the tick specimens that bit the patients could be identified.ResultsWe report a clinical case of spotted fever rickettsiosis that was acquired in an Atlantic forest area in Bahia state, northeast Brazil. The case was determined to be caused by R. parkeri strain Atlantic rainforest, based on molecular analysis of the crust removed from the tick bite site (inoculation eschar) of the patients’ skin. DNA extracted from the crust yielded partial sequences of three rickettsial genes (gltA, ompA and ompB), which were 99–100% identical to R. parkeri strain Atlantic rainforest. The tick specimen that was attached to patient skin was identified as a female of A. ovale.ConclusionsWe report the fourth confirmed case of spotted fever rickettsiosis caused by R. parkeri strain Atlantic rainforest, providing to our knowledge for the first time, direct evidence of R. parkeri strain Atlantic rainforest transmission by A. ovale.

Reassortments among Avian Influenza A(H5N1) Viruses Circulating in Indonesia, 2015-2016.

Highly pathogenic avian influenza (HPAI) A(H5N1) viruses have been circulating since 2003 in Indonesia, with major impacts on poultry health, severe economic losses, and 168 fatal laboratory-confirmed human cases. We performed phylogenetic analysis on 39 full-genome H5N1 virus samples collected during outbreaks among poultry in 2015–2016 in West Java and compared them with recently published sequences from Indonesia. Phylogenetic analysis revealed that the hemagglutinin gene of all samples belonged to 2 genetic groups in clade 2.3.2.1c. We also observed these groups for the neuraminidase, nucleoprotein, polymerase, and polymerase basic 1 genes. Matrix, nonstructural protein, and polymerase basic 2 genes of some HPAI were most closely related to clade 2.1.3 instead of clade 2.3.2.1c, and a polymerase basic 2 gene was most closely related to Eurasian low pathogenicity avian influenza. Our results detected a total of 13 reassortment types among HPAI in Indonesia, mostly in backyard chickens in Indramayu.

Epidemiology of human infections with highly pathogenic avian influenza A(H7N9) virus in Guangdong, 2016 to 2017.

We describe the epidemiology of highly pathogenic avian influenza (HPAI) A(H7N9) based on poultry market environmental surveillance and laboratory-confirmed human cases (n = 9) in Guangdong, China. We also compare the epidemiology between human cases of high- and low-pathogenic avian influenza A(H7N9) (n = 51) in Guangdong. Case fatality and severity were similar. Touching sick or dead poultry was the most important risk factor for HPAI A(H7N9) infections and should be highlighted for the control of future influenza A(H7N9) epidemics.

Epidemiology of avian influenza A H7N9 virus in human beings across five epidemics in mainland China, 2013–17: an epidemiological study of laboratory-confirmed case series

The avian influenza A H7N9 virus has caused infections in human beings in China since 2013. A large epidemic in 2016-17 prompted concerns that the epidemiology of the virus might have changed, increasing the threat of a pandemic. We aimed to describe the epidemiological characteristics, clinical severity, and time-to-event distributions of patients infected with A H7N9 in the 2016-17 epidemic compared with previous epidemics. In this epidemiological study, we obtained information about all laboratory-confirmed human cases of A H7N9 virus infection reported in mainland China as of Feb 23, 2017, from an integrated electronic database managed by the China Center for Disease Control and Prevention (CDC) and provincial CDCs. Every identified human case of A H7N9 virus infection was required to be reported to China CDC within 24 h via a national surveillance system for notifiable infectious diseases. We described the epidemiological characteristics across epidemics, and estimated the risk of death, mechanical ventilation, and admission to the intensive care unit for patients admitted to hospital for routine clinical practice rather than for isolation purpose. We estimated the incubation periods, and time delays from illness onset to hospital admission, illness onset to initiation of antiviral treatment, and hospital admission to death or discharge using survival analysis techniques. Between Feb 19, 2013, and Feb 23, 2017, 1220 laboratory-confirmed human infections with A H7N9 virus were reported in mainland China, with 134 cases reported in the spring of 2013, 306 in 2013-14, 219 in 2014-15, 114 in 2015-16, and 447 in 2016-17. The 2016-17 A H7N9 epidemic began earlier, spread to more districts and counties in affected provinces, and had more confirmed cases than previous epidemics. The proportion of cases in middle-aged adults increased steadily from 41% (55 of 134) to 57% (254 of 447) from the first epidemic to the 2016-17 epidemic. Proportions of cases in semi-urban and rural residents in the 2015-16 and 2016-17 epidemics (63% [72 of 114] and 61% [274 of 447], respectively) were higher than those in the first three epidemics (39% [52 of 134], 55% [169 of 306], and 56% [122 of 219], respectively). The clinical severity of individuals admitted to hospital in the 2016-17 epidemic was similar to that in the previous epidemics. Age distribution and case sources have changed gradually across epidemics since 2013, while clinical severity has not changed substantially. Continued vigilance and sustained intensive control efforts are needed to minimise the risk of human infection with A H7N9 virus. The National Science Fund for Distinguished Young Scholars.

Detection and Molecular Characterization of the Avian Influenza A (H7N9) Virus in Eastern China in 2013

Background: On March 31, 2013, human infections with a novel avian influenza A (H7N9) virus were firstly reported in China. By February 7, 2015, a total of 562 laboratory-confirmed human cases of H7N9 infection were reported in mainland China. Objectives: This study aimed to determine whether there is a novel H7N9 virus infection in human and animals in Taizhou city, China, in 2013. Methods: In this study, we developed real-time reverse transcription-polymerase chain reaction (RT-PCR) assays to detect H7N9 virus infection in human and animals (chicken, pig, and pigeon) in Taizhou city in the beginning of H7N9 epidemics of 2013. Also, we studied the novel isolated H7N9 virus strain by using genome sequencing and phylogenetic analysis. Results: Of 150 samples tested, 7 were detected to be H7N9 positive which all were collected from chickens. Also, a novel H7N9 virus strain (A/chicken/jiangsu/1021/2013) was isolated and studied. Phylogenetic analysis showed the novel isolated H7N9 virus had high identity to the four novel human H7N9 viruses (A/Shanghai/1/2013, A/Shanghai/2/2013, A/Anhui/1/2013, and A/Hangzhou/1/2013). Conclusions: Our results demonstrated a novel H7N9 virus in chickens in Taizhou city in 2013 that may pose a potential risk to public health.

Genotyping and detection of common avian and human origin-influenza viruses using a portable chemiluminescence imaging microarray.

Background Influenza viruses are divided into three types, A, B, and C. Human influenza A and B viruses can cause seasonal epidemics, but influenza C causes only a mild respiratory illness. Influenza A virus can infect various host species. In 2013, human-infectious avian influenza A (H7N9) was first reported in China. By the second week of 2014, there were 210 laboratory-confirmed human cases in the country, and the mortality rate eventually reached 22 %. Rapid and accurate diagnosis of influenza viruses is important for clinical management and epidemiology. MethodsIn this assay, a cost-effective chemiluminescence (CL) detection oligonucleotide microarray was developed to genotype and detect avian influenza A (H7N9), avian influenza A (H5N1), 2009 influenza A (H1N1), seasonal influenza A (H1N1), and seasonal influenza A (H3N2). Influenza A viruses and influenza B viruses were also generally detected using this microarray.ResultsThe results of detection of 40 cultivated influenza virus strains showed that the microarray was able to distinguish the subtypes of these influenza viruses very well. The microarray possessed similar or 10 fold higher limit of detection than the real-time RT-PCR method. Sixty-six clinical swab samples were detected using this microarray and verified with real time RT-PCR to evaluate the efficiency of this microarray for clinical testing.ConclusionsA reliable CL detection oligonucleotide microarray had been developed to genotype and detected these influenza viruses.

Human polyclonal immunoglobulin G from transchromosomic bovines inhibits MERS-CoV in vivo.

As of 13 November 2015, 1618 laboratory-confirmed human cases of Middle East respiratory syndrome coronavirus (MERS-CoV) infection, including 579 deaths, had been reported to the World Health Organization. No specific preventive or therapeutic agent of proven value against MERS-CoV is currently available. Public Health England and the International Severe Acute Respiratory and Emerging Infection Consortium identified passive immunotherapy with neutralizing antibodies as a treatment approach that warrants priority study. Two experimental MERS-CoV vaccines were used to vaccinate two groups of transchromosomic (Tc) bovines that were genetically modified to produce large quantities of fully human polyclonal immunoglobulin G (IgG) antibodies. Vaccination with a clade A γ-irradiated whole killed virion vaccine (Jordan strain) or a clade B spike protein nanoparticle vaccine (Al-Hasa strain) resulted in Tc bovine sera with high enzyme-linked immunosorbent assay (ELISA) and neutralizing antibody titers in vitro. Two purified Tc bovine human IgG immunoglobulins (Tc hIgG), SAB-300 (produced after Jordan strain vaccination) and SAB-301 (produced after Al-Hasa strain vaccination), also had high ELISA and neutralizing antibody titers without antibody-dependent enhancement in vitro. SAB-301 was selected for in vivo and preclinical studies. Administration of single doses of SAB-301 12 hours before or 24 and 48 hours after MERS-CoV infection (Erasmus Medical Center 2012 strain) of Ad5-hDPP4 receptor-transduced mice rapidly resulted in viral lung titers near or below the limit of detection. Tc bovines, combined with the ability to quickly produce Tc hIgG and develop in vitro assays and animal model(s), potentially offer a platform to rapidly produce a therapeutic to prevent and/or treat MERS-CoV infection and/or other emerging infectious diseases.