News Scan for May 22, 2019

News brief

Saudi Arabia records new MERS case

Saudi Arabia's Ministry of Health (MOH) today reported one more MERS-CoV case, which involves a patient from Al Kharj. This is the second case to originate in that city in the past week.

A 44-year-old woman who didn't have contact with camels and whose exposure to MERS-CoV (Middle East respiratory syndrome coronavirus) is listed as secondary, meaning she was likely exposed by another known patient, is the latest case noted in the MOH's epidemiologic week 21 report.

Al Kharj is in Riyadh province, located in the central part of the country. The Saudi Arabian MOH has confirmed 141 MERS cases so far this year.
May 22 MOH


WHO certifies Algeria and Argentina as malaria-free

The World Health Organization (WHO) today announced that Algeria and Argentina have achieved certification of malaria-free status, meaning both have interrupted local transmission for at least 3 consecutive years.

In an announcement, the WHO said Algeria—where the disease was first discovered in humans in 1880—is only the second country in its African region to reach malaria-free status. The first was Mauritius, which was certified in 1973. And Argentina is the second country in the Americas region to be certified in 45 years, following Paraguay in 2018. Algeria and Argentina reported their last indigenous malaria cases in 2013 and 2010, respectively.

The WHO grants malaria-free certification when a country has proven, beyond a reasonable doubt, that the chain indigenous transmission has been interrupted for at least the previous 3 consecutive years. Countries must also have surveillance systems that can rapidly detect and respond to any malaria cases and have effective programs to prevent malaria re-establishment.

Officials from Algeria and Argentina received their certificates today from WHO Director-General Tedros Adhanom Ghebreyesus, PhD, on the sidelines of the World Health Assembly underway in Geneva this week. In the WHO statement, Tedros said the two countries eliminated malaria due to the unwavering commitment and perseverance of their people and leaders. "Their success serves as a model for other countries working to end this disease once and for all."
May 22 WHO statement


Chikungunya vaccine candidate proves safe, immunogenic in phase 1 trial

A chikungunya vaccine, VLA1553, developed by Valneva, was safe and immunogenic up to 7 months, according to new results from a multi-dose phase 1 clinical trial of the vaccine.

The study, conducted on 120 healthy volunteers ages 18 to 45, tested the immunogenicity of three different doses of the vaccine; all participants reached seroconversion 14 days after the  vaccine injection, with results sustained at 6 months, according to a Valneva news release.

The trial also showed that vaccinees were protected from vaccine-induced viremia when re-vaccination occurred at month 6 for some participants. The results suggest VLA1553 is a strong final product candidate, the company said.

"The data indicate that vaccinated subjects are protected from chikungunya viremia.This marks a very important milestone getting us a step closer to a highly competitively differentiated vaccine addressing a serious threat to public health," said Wolfgang Bender, MD, PhD, the chief medical officer of Valneva.
May 22 Valneva press release

Flu Scan for May 22, 2019

News brief

Clinical guideline developed for flu testing in emergency departments

US scientists have developed and validated a clinical decision guideline (CDG) for flu testing in emergency departments, according to a study yesterday in Clinical Infectious Diseases.

To develop the CDG, researchers conducted a cohort study involving 1,941 patients with fever or respiratory symptoms seen at four US emergency departments in 2013 and 2014. Of those patients, 118 (9.4%) tested positive for influenza virus.

Based on clinical signs and intake, the researchers derived a CDG that included four criteria: new or increased cough (2 points), headache (1 point), subjective fever (1 point), and triage temperature greater than 100.4°C (1 point). A score of 3 or more points indicated influenza testing was warranted. 

When applied to study participants, 66.1% of the symptomatic population met the CDG criteria for influenza testing. The CDG is not meant to be used in pediatric populations, the authors said, and should be used in conjunction with highly sensitive influenza testing.

"The use of this CDG in practice could have important impacts on individual patient's treatment, as well as the population as a whole, through focused infection control measures," the authors said.
May 21 Clin Infect Dis study


Genetic analysis of Midwest poultry H5N2 outbreaks yields new clues

A new analysis of highly pathogenic H5N2  avian flu outbreaks that struck the Midwestern poultry industry in 2015 found that road density was a driver of viral spread, hinting a human role in carrying the virus between farms, and multiple introductions from wild birds doesn't appear likely. Researchers from the University of Georgia, the University of Connecticut, and the US Department of Agriculture published their findings yesterday in the preprint server bioRxiv.

To learn more about what fueled the outbreak, the group analyzed 182 full-genome H5N2 sequences collected from commercial layer and turkey farms hit by the outbreaks and then factored the information into models that included epidemiologic and geographic information.

The investigators found that layer chickens and turkeys seemed to represent two separate host populations that interacted with each other, but did not receive the virus from an ongoing external source. Their models suggested that layer chicken farms were infectious much longer than turkey farms, possibly explaining why the transmission rate from chicken farms to turkey farms was higher than from turkey farms to chicken farms. Though turkeys survived longer than chickens, turkey premises were depopulated more quickly than layer facilities.

The researchers note that their genetic findings support earlier findings that virus spread among Minnesota's poultry farms were distance-dependent. High road-density findings correlate with better logistic connectivity between farms, boosting the chances that an infected farm will export the virus to nearby farms and counties, a factor seen in earlier poultry outbreaks overseas. One factor they looked at that had a relatively small effect size was the proportion of a county covered by surface water, which in countries like China has been associated with greater avian influenza dispersal due to waterfowl migration.

Implications for future surveillance and control may be that though wild birds can initially introduce the virus, outbreaks can be maintained without additional ones, the team wrote. Biosecurity measures may have been enough to prevent continued introductions from outside sources, but may not have been as effective against local farm-to-farm transmission. The authors point out that biosecurity factors might explain why the Midwest's broiler chicken industry was spared from the outbreak.

A better understanding of how affected farms are connected would help with control efforts, they say. "With the knowledge of how these farms share personnel and equipment, future outbreaks could be contained by disruption of the transportation network," they wrote.
May 21 bioRxiv study

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