MERS vaccine enters human trial; more details on Thai case
A pair of US biotechnology companies today announced the launch of what appears to be the first phase 1 clinical trial of a MERS-CoV vaccine, while the World Health Organization (WHO) provided more details on the MERS-CoV case reported in Thailand earlier this week.
Inovio Pharmaceuticals, Inc. and GeneOne Life Science, Inc. are recruiting participants for a safety and immunogenicity study of GLS-5300, a MERS-CoV (Middle East respiratory syndrome coronavirus) vaccine developed by Inovio, the company said in a press release. The study will take place at Walter Reed Army Institute of Research in Silver Spring, Md.
Studies in rhesus macaques last year found that GLS-5300 induced 100% protection from live MERS-CoV virus. Observations of the vaccine's effectiveness in mice, camels, and non-human primates showed that it prevented live virus from infecting cells in all species.
"Our broad experience with DNA-based immunotherapies and with MERS specifically suggests we can potentially make an important contribution to developing such a solution," said Inovio President and Chief Executive Officer Dr. J. Joseph Kim.
Jan 28 Inovio Pharmaceuticals press release
Meanwhile, today’s WHO statement on the MERS case in Thailand said the patient, a 71-year-old Omani man who flew from Oman to Bangkok on Jan 22, had had contact with camels before he fell ill.
The man had preexisting medical conditions and a history of camel exposure in the two weeks prior to developing MERS-CoV symptoms, the WHO said. His case is the second MERS infection confirmed in Thailand.
The man became ill on Jan 14 and was hospitalized in Oman on Jan 18, the agency reported. He discharged himself from the hospital on Jan 21, flew to Thailand, and was hospitalized in Bangkok on Jan 23. Samples taken by both the Omani and Thai hospitals tested positive for MERS-CoV.
Omani and Thai officials are currently tracing people who may have been exposed to the virus in Oman, Bangkok, and during the patient’s journey, the WHO said.
Adult GBS cluster in Wales paralleled acute paralysis in kids
Welsh researchers yesterday reported a cluster of 10 unusual Guillain-Barre syndrome (GBS) cases in adults that coincided with four child cases of acute flaccid paralysis (AFP) over a 3-month period last fall.
Writing in Eurosurveillance, the researchers said the cause of the GBS cluster is unclear, nor is it known whether it was related to the AFP cases, two of which involved infections with enterovirus D-68 (EV-D68).
GBS is a peripheral nerve disorder that usually involves ascending paralysis and is thought to be an autoimmune condition triggered by various infectious agents, including Campylobacter, influenza, and West Nile viruses, the report notes. More recently, a Zika virus connection is suspected in a number of GBS cases.
The GBS cases involved 10 men in South Wales between the ages of 24 and 77. Seven of them had facial diplegia (bilateral paralysis) at the onset of illness, and studies showed axonal involvement—an unusual feature of GBS—in five. Seven of the 10 reported various respiratory infections of various kinds that preceded the neurologic symptoms.
The four children with AFP ranged from 1 to 13 years old, but three were 2 years or younger. Of three who underwent enterovirus testing, two had evidence of EV-D68 in stool or respiratory samples.
The report notes that EV-D68 is one of the possible pathogens or diagnoses associated with the clinical presentation of AFP, along with GBS and poliomyelitis. In 2014 the United States had a nationwide EV-D68 outbreak involving more than 1,100 known cases, nearly all in children.
"There is no clear hypothesis as yet for the cause of the adult cluster," the researchers wrote. "The temporal association of the two clusters could represent a coincidence, or an artifact due to changes in local diagnosis." They said they are investigating the possibility of infections with EV-D68 and other enteroviruses, Campylobacter, and influenza virus. Zika and West Nile viruses are deemed unlikely causes because of the lack of suitable insect vectors in Wales and any appropriate travel history.
The researchers also noted that neurologic illness due to EV-D68 has not previously been described in Wales and is rare in the United Kingdom as a whole.
Jan 28 Eurosurveill report
Study finds low risk of in-flight TB transmission
The risk of contracting tuberculosis (TB) on aircraft is very low and significantly associated with close proximity to infected individuals, according to findings reported yesterday in Eurosurveillance.
Researchers from four European agencies, including the European Centre for Disease Prevention and Control (ECDC), analyzed 21 published studies of contact tracing following flights in which travelers were exposed to a patient with confirmed TB infection.
Only one study demonstrated evidence for in-flight TB transmission, observing that six passengers sitting next to the index case later tested positive on a tuberculin skin test (TST).
Seven studies showed some evidence of possible TB transmission on aircraft, though researchers noted that transmission on the ground could not be excluded in these instances. No cases of active TB following conversion to a positive TST result after aircraft exposure have been reported.
Of the 1,287 total travelers with available test results represented in the analysis, 10 (0.8%) were possibly infected on the aircraft, 7 (0.5%) of whom converted to a positive TST. Of 905 people sitting within the five rows around the infected person, 12 (1.3%) were possibly infected, 1 (0.1%) of whom converted to a positive skin test result.
Researchers used the results of this analysis to inform revisions to the ECDC's Risk Assessment Guidelines for Infectious Diseases Transmitted on Aircraft (RAGIDA-TB). Updates included recommendations for initiating contact investigations only when a positive TB diagnosis occurs within 3 months after the flight, prioritizing contacts sitting within two seats of the index patient, and beginning contact tracing only when there is evidence of transmission between the index patient and close contacts.
Based on the results of this review, the researchers said that risk of TB transmission on aircraft is very low, though its occasional incidence still requires close collaboration between international partners for contact tracing and risk assessment.
Jan 28 Eurosurveill study
More vaccine-derived polio in Laos triggers public health emergency
Health officials in Laos recently reported two more cases of vaccine-derived poliovirus 1 (VDPV1) to the World Health Organization (WHO), boosting the country's recent total to seven, according to a statement today.
The cases involve a 14-month-old boy from Xaisomboun province, an area of Laos where the last two illnesses were reported. His illness started on Nov 16 with a fever, progressing to asymmetrical paralysis 2 days later. He had received three doses of oral polio vaccine. Though his samples were negative for polio virus, a sample taken from his asymptomatic sister was positive. The case was classified as VDPV1 based on the epidemiological link with his sister and another from the same area, signaling that the virus is circulating in that location.
The second case is that of a 40-year-old man from the same district and province who first had hyporeflexia and symmetric paralysis of both legs on Dec 18. He had no history of other neurological disease or other conditions, and he had not received the oral vaccine. On Jan 9, lab sampling confirmed the VDPV1 finding.
The country's prime minister declared an outbreak as public health emergency on Jan 13, and a fourth round of supplemental immunization activities with oral polio vaccine is planned.
Jan 29 WHO statement