This study aims to conduct pilot surveillance for Nipah virus (NiV), Japanese encephalitis virus (JEV), and Crimean-Congo hemorrhagic fever virus (CCHFV) in East Malaysia, Mexico, Mongolia, and Northern Vietnam. NiV is a highly lethal paramyxovirus that is transmitted from bats and pigs, causing severe encephalitis with a 58% fatality rate. JEV is a flavivirus transmitted by mosquitoes that causes encephalitis in rural and peri-urban Asia, with a 30% fatality rate for symptomatic cases. CCHFV is a bunyavirus transmitted by ticks or infected blood, causing severe hemorrhagic fever with 40% fatality in hospitalized cases. This study will partner with the National Bio and Agro-Defense Facility (NBAF) in attempting to identify and characterize viruses or serological evidence of such viral infections in wildlife and livestock in the four countries.  identify and characterize these viruses in Data from this study may inform future public health interventions and targeted surveillance efforts. 

Often serious viral illnesses are identified via carefully designed molecular laboratory tests.  However, sometimes these carefully designed tests for known pathogens will miss newly identified or rare pathogens.  Through this research project we are working closely with international collaborators and the US Department of Agriculture in seeking to identify such new or rare viruses. Specifically, this study seeks to identify Nipah viruses, Japanese encephalitis viruses, Crimean-Congo Hemorrhagic Fever viruses and other related viruses that might be causing hospitalizations in Malaysia, Mexico, Mongolia, and Vietnam. As we identify such viruses, we will characterize them with a goal of better understanding their epidemiology and developing countermeasures to reduce their future morbidity and mortality.

PI - Gregory Gray

In early 2017, a 5th wave of H7N9 avian influenza (AI) virus infections in man demonstrated the increasing spread of H7N9 virus among poultry in China. In 1997, highly pathogenic H5N1 AI virus outbreaks were reported in Hong Kong and soon became widely spread among poultry in China. It eventually crossed the border into Vietnam and became enzootic among Vietnam’s aquatic birds and poultry. There is growing concern that H7N9 will likewise become enzootic among poultry in Vietnam and cause frequent severe infections in man. Surveillance for AI viruses in Vietnam is very limited.

During the first three weeks of October 2017, Duke, Duke-NUS, and NIVR partnered in conducting a pilot study of aerosol and bird tracheal swab sampling in Hanoi’s largest live bird market (Havi). Ninety percent of 30 four-hour aerosol samples were positive for influenza A by qRT-PCR and these results correlated highly with pooled oral swab cultures from nearby live birds which were 47% qRT-PCR positive. Egg cultures of aerosol and pooled oral swab cultures yielded 26 live viruses, five of which were H5.  In this pilot, there was as yet no evidence of H7 viruses in this market.  Our NIVR collaborators believe this bird market to be at high risk of incursions with H7 viruses from China.

In this proposal, we will conduct a 12-month pilot study of active surveillance for influenza A viruses at Hanoi’s largest bird market and in six live bird markets sites near Vietnam’s northern border with China. Our teams will travel to the live bird market in Hanoi weekly and to six live bird markets in three remote provinces in Vietnam, conducting 10 market visits per month. During these market visits, we will employ novel bioaerosol AI surveillance techniques (less invasive, larger sampling area, more sustainable), along with bird and cage swabbing, as well as collect nasal washes and qualitative survey-based interviews from a convenience sample of poultry workers. Molecular and culture work will be performed at NIVR in Hanoi with close collaboration (periodic visits) from Duke and Duke-NUS scientists. We estimate a 12-month total of 360 bioaerosol samples, 600 bird swab samples, 1200 environmental cage swab samples, and 600 poultry worker nasal wash samples with questionnaires. The samples will be studied with molecular assays, egg or virus culture, and when appropriate by sequencing studies in our Duke One Health laboratory network to determine influenza A type.

PI - Dr. Gayani Tillekeratne, Division of Infectious Diseases and the Duke Global Health Institute, Duke University
Dr. Gregory Gray, Division of Infectious Diseases, University of Texas Medical Branch
Dr. Benjamin Anderson, Duke Kunshan University, Kunshan, China

During the last 25 years the world has experienced the emergence and spread of a number of novel respiratory viruses including Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) in 2003 and 2004, and now SARS-CoV-19. Similarly, in 2009, a triple reassortment H1N1 swine-like influenza virus emerged in Mexico, and quickly spread throughout the world. While these novel emergent respiratory viruses are from different families, they have one thing in common, they are thought to have originated in animal and crossed over to infect man. While a variety of risk factors associated with emerging respiratory viruses have been study, the risk factors for specific viruses are complex; however, they tend to be found in densely populated geographic areas of high emerging infectious disease risk and are also often correlated with live animal markets and industrialized farming.

The primary aim of the study is to identify and characterize viruses and determine risk factors associated with pneumonia among patients admitted to participating hospitals in Malaysia, Sri Lanka, Kenya, China, and Vietnam. Teams at collaborating institutions will enroll and collect nasopharyngeal (NP) swab and conduct qualitative surveys to determine risk factors associated with pneumonia. NP swab samples will be studied with molecular assays, virus culture, and when appropriate by sequencing, to characterize viruses. We will also study the laboratory results with their linked questionnaire data with a goal of identifying potential risk factors for pneumonia hospitalization.