News Scan for Oct 23, 2014

News brief

CDC confirms more EV-D68 cases, unexplained polio-like illnesses

The national tally of confirmed enterovirus 68 (EV-D68) cases has jumped by 32, to 973, and the count of unexplained and possibly related neurologic-illnesses has increased to 51, the Centers for Disease Control and Prevention (CDC) reported today.

The EV-D68 cases, which involve severe respiratory illness, occurred in 47 states and Washington, DC, the CDC said. Almost all the cases have been in children, many of whom have asthma.

The number of deaths in patients who were infected with the virus is now eight, and investigations on the role of the virus in the deaths are continuing, the CDC said. It said state and local officials are taking the lead in those efforts.

Although the number of confirmed cases is climbing as the CDC continues testing samples, reports from states point to decreasing activity, the agency reported. It said 34 states cited low or declining cases, while 8 states reported elevated cases and 1 reported increasing activity.

The CDC said it has tested more than 1,700 samples thus far.

Meanwhile, the agency said it has now verified 51 recent reports of unexplained neurologic illness with limb weakness in children in 23 states. That compares with 37 cases in 16 states a week ago.

The investigation of the polio-like illnesses began with a cluster of 10 cases in Colorado, in which four patients tested positive for EV-D68. But the agency has not yet reported any findings on whether the virus was a factor in the Colorado cases or others.

The CDC said it was still investigating about six more cases. It defines a case as acute onset of focal limb weakness on or after Aug 1 in patients no more than 21 years old, with a lesion in the spinal cord gray matter as seen on MRI.
CDC 2014 EV-D68 page
CDC information on investigation of neurologic illnesses

Qatar confirms its second MERS case in 10 days

Qatar has confirmed its second case of MERS-CoV in 10 days, this one in a 43-year-old man, according to a report today in the Qatari newspaper The Peninsula.

The man experienced a fever for several days and was diagnosed as having pneumonia at a hospital emergency department. Subsequent testing confirmed the presence of MERS-CoV (Middle East respiratory syndrome coronavirus).

Qatar's Supreme Council of Health (SCH) said yesterday that no health workers at the hospital who had contact with him have tested positive for MERS-CoV and that all his personal contacts would be monitored for 2 weeks, according to the Peninsula story.

The newest case brings Qatar's MERS case count to 11, 5 of them fatal. The previous case, the first in Qatar since last November, was reported Oct 12. The SCH said the 71-year-old patient is improving, reported the Peninsula today. That patient had traveled to Saudi Arabia; no information regarding travel was given for today's case.
Oct 23 Peninsula story
Oct 13 CIDRAP News scan on previous case

Researchers say US pause on 'gain-of-function' research is too broad

Some researchers at a meeting yesterday complained that the US government's suspension of funding for "gain-of-function" (GOF) research on certain viruses goes too far and may impede the development of seasonal flu vaccines and antiviral drugs, according to a Nature news story today.

The White House of Science and Technology Policy (OSTP) announced on Oct 17 the suspension of funding for GOF studies—those that may lead to increased virulence or transmissibility—on influenza, MERS-CoV (Middle East respiratory syndrome coronavirus) and SARS coronavirus. The aim is to allow time to thoroughly assess the risks and benefits and to develop a federal policy.

The suspension drew objections form researchers yesterday at a meting of the National Science Advisory Board for Biosecurity (NSABB), Nature reported. The panel is to play a lead role in the risk assessment and policy development.

Among scientists who said the National institutes of Health has ordered them to stop work was Stacey Schultz-Cherry, an infectious-disease specialist at St. Jude Children’s Research Hospital in Memphis, who works with the World Heatlh Organization (WHO), the story said.

Showing the NSABB an example of the type of data the WHO uses to choose strains for seasonal flu vaccines, she said some gain-of-function research is necessary to determine not only how transmissible strains are, but also how they might mutate to evade whatever vaccine the WHO chooses.

Schultz-Cherry said her lab received a stop-work order even though the ban does not cover research on naturally occurring viruses, according to Nature. "They don’t want the ban to impact seasonal flu, but there’s no doubt that it does," she said. "What it has just stopped are vaccine-escape studies. It absolutely will trickle down to public health."

Bill Sheridan, senior vice-president of BioCryst Pharmaceuticals in Durham, N.C., echoed Schultz-Cherry's concerns, according to the story. Because drug development is financially risky, he said, private companies' research on antiviral drugs and vaccines will also come to a halt if some GOF research is not allowed to proceed.
Oct 23 Nature story
Related Oct 17 CIDRAP News item

Flu Scan for Oct 23, 2014

News brief

Report details H3N2 flu outbreak in highly vaccinated crew

In February a US Navy minesweeper moored in San Diego harbor experienced an influenza-like illness (ILI) outbreak that affected a quarter of the crew—much of it attributed to H3N2 flu—even though almost all of them had received influenza vaccine, according to a report today in Morbidity and Mortality Weekly Report (MMWR).

Scientists from the Navy and the Centers for Disease Control and Prevention reported that, over the course of 3 days in mid-February, 25 of 102 USS Ardent crew members sought medical care because of ILI. Polymerase chain reaction testing of nasal swab specimens showed that 20 were positive for influenza A, of which 18 were subtyped as H3N2. The other 2 could not be subtyped.

Sequence analysis showed the virus infecting the crew to be antigenically similar to the H3N2 component of the vaccine, the researchers reported.

To reduce disease spread and impact, patients with ILI were prescribed oseltamivir (Tamiflu), and other outbreak-reduction steps were taken aboard the ship. The authors note that 99% of the crew had received flu vaccine, including 24 of the 25 with ILI. The ill crew members lost 43 cumulative working days.

Because San Diego County officials had reported H3N2 circulating in the weeks leading up to the shipboard outbreak, the authors said the disease was likely acquired from the local community.
Oct 24 MMWR report

Study: Low rates of H7N9 transmission by three routes in Guangdong

The risk to humans of new infection with H7N9 avian influenza is low in the early stages of circulation of the virus, according to a study today in Virology Journal of people in Guangdong province, one of the epicenters of the 2013-14 H7N9 outbreak in China.

The first human cases of H7N9 were detected in eastern China in March 2013. Officials in Guangdong province, in the south, confirmed cases in poultry in April 2013, found the virus in environmental samples in May 2013, and detected the first human case in a woman in July of that year.

The authors conducted serologic studies of three groups of individuals in Guangdong early in the epidemic using hemagglutinin inhibition (HI) and microneutralization (MN) assays with H7N9 viruses from infected patients, infected poultry, and contaminated environments as antigens.

The three groups sampled were considered to be at risk for H7N9: 125 people exposed to the index patient, 240 people likely exposed to the first infected poultry, and 196 people potentially exposed to environments contaminated with the virus.

Among the 561 total samples screened for antibodies to viruses, 7 from those exposed to contaminated environments were positive on HI and 1 of those was positive on MN using poultry H7N9 as the antigen. One sample was positive on HI against human H7N9, and three were positive on HI against environmental H7N9 in the group exposed to the index patient; none of these were positive on MN. All HI titers in the group with likely poultry exposure were less than 40 using all three viruses as antigens.

The authors say, "The antigenic sites of [hemagglutinin] proteins of the H7N9 strains from different hosts were highly conserved," and they conclude, "The risk of new infection is low in individuals who have contact with infected patients, poultry, or a contaminated environment in the early stages of the circulation of the H7N9 virus."
Oct 23 Virology J abstract