News Scan for May 02, 2018

News brief

Strain of hypervirulent, carbapenem-resistant Klebsiella found in China

Scientists in China are reporting the emergence of a new strain of hypervirulent, carbapenem-resistant of Klebsiella pneumoniae.

In a study published in Antimicrobial Agents and Chemotherapy, researchers from Sichuan University report that the strain, WCHKP13F2, was isolated in 2015 from a patient who had severe burns and a healthcare-associate bloodstream infection. The K pneumoniae isolate was resistant to several antibiotics, including imipenem and meropenem. The patient discharged himself in spite of unsolved critical illness.

Whole-genome sequencing revealed that the isolate belonged to sequence type 36, a known hypervirulent K pneumoniae (hvKP) strain with a worldwide distribution, and testing confirmed hypervirulence. Further analysis identified several plasmid-mediated hypervirulence genes and antibiotic resistance genes, including the carbapenemase gene blaKPC-2.

"The combination of carbapenem resistance and hypervirulence significantly compromises options of antimicrobial agents for treating the life-threatening infections caused by carbapenem-resistant hvKP and therefore represents a major urgent challenge for clinical treatment, infection control, and public health," the authors write. "Surveillance of carbapenem-resistant hvKP is urgently required to generate essential information for preventing their spread."
Apr 30 Antimicrob Agents Chemother abstract

Antiviral treatment for smallpox gets green light from FDA panel

SIGA Technologies, the maker of TPOXX, a small-molecule antiviral treatment for smallpox, announced today that an advisory panel for the US Food and Drug Administration (FDA) unanimously concluded that the drug's benefits outweigh its risks.

The FDA's Antimicrobial Drugs Advisory Committee voted 17-0 in favor of oral TPOXX. The vote precedes a probable favorable review for TPOXX's pending New Drug Application (NDA).

"We believe that safety and efficacy data contained in the NDA support TPOXX's future use as a medical countermeasure in response to a smallpox outbreak," said SIGA CEO Phil Gomez, PhD.

The FDA has previously announced that its target final action date for oral TPOXX is Aug 8. SIGA developed the treatment with funding from the US government’s Biomedical Advanced Research and Development Authority (BARDA). According to SIGA, BARDA has acquired 2 million courses of oral TPOXX, which have been delivered to the Strategic National Stockpile.
May 1 SIGA press release

Four more Lassa fever cases confirmed in Nigerian outbreak

In a weekly Lassa fever outbreak update, Nigeria's Centre for Disease Control (NCDC) reported four new confirmed cases and one death. The Lassa fever outbreak, Nigeria's largest recorded, has been ongoing since January, but case counts have slowed in recent weeks.

From Jan 1 to Apr 29, the NCDC has confirmed 420 Lassa fever cases, along with 106 deaths. The case-fatality rate is holding at 25.2 %. None of the new cases involved health workers. So far, 37 healthcare workers from eight states have been sickened in the outbreak.

Four people are still hospitalized for treatment, the NCDC said. Officials reported new cases in Edo, Ondo, and Taraba states. In this outbreak, 42% of cases are from Edo and 23% are from Ondo.

Lassa fever is endemic in Nigeria, and though it is mainly transmitted by rats, human spread can occur from contact with an infected person's bodily fluids.
Apr 29 NCDC report

WHO confirms large dengue outbreak in Reunion, France

The World Health Organization (WHO) confirmed yesterday a spike of dengue cases in Reunion, France, a territory in the Indian Ocean.

Since January, Reunion has recorded 1,816 cases of the flavivirus disease, with 428 probable and confirmed cases reported from Apr 16 to Apr 23. Reunion recorded only 100 cases of the virus in 2017.

The WHO said the huge uptick in cases could be explained be several factors, including asymptomatic spread in 2017 that carried into this year, and a lack of herd immunity in the local population.

"Reunion is a popular tourist destination, and the likelihood of dengue virus introduction to other countries is heightened by the current outbreak," the WHO said.
May 1 WHO statement

Flu Scan for May 02, 2018

News brief

Meta-analysis finds no protection drop-off with consecutive flu vaccination

A new meta-analysis of 42 flu studies found that vaccination over two consecutive seasons didn't reduce flu vaccine effectiveness (VE) compared with people vaccinated during the current season, but the researchers included the caveat that the overall quality of evidence was low, due to inconsistency and imprecision among the studies. A team based at McMaster University in Canada reported its findings yesterday in Vaccine.

Of the 42 studies that met the group's inclusion criteria, 5 were randomized controlled trials (RCTs) and 39 were observational studies. The studies covered 23 flu seasons, from 1983-84 to the middle of the 2016-17 season. In the 5 RCTs, which had 11,987 participants, VE for those vaccinated over two consecutive seasons was 71% (95% confidence interval [CI], 62% to 78%), compared with 58% in those vaccinated in the current season (95% CI, 48% to 66%). The team saw a similar pattern for the observational studies, which had 28,627 participants.

Subgroup analysis also supported the findings, but a dose-response analysis did show a reduced effectiveness in those who had three or more consecutive vaccinations.

Overall, the researchers said the findings were generally consistent with previously reported studies. In noting that the findings don't rule out the possibility of reduced effectiveness, the investigators said that reporting vaccine history using the exact number of doses and composition across multiple prior years in future observational studies could help tease out the biological mechanism behind the impact of two or more consecutive vaccinations.

"Furthermore, it is critical that assessment and reporting of antigenic drift and vaccine match be improved in future studies," they wrote.
May 1 Vaccine abstract

Countries report sporadic detections of H5N6, H5N8, H5N2 avian flu

Over the past week, four countries reported new highly pathogenic avian flu detections involving different strains, according to the latest notifications from the World Organization for Animal Health (OIE).

Outbreaks in Germany and Japan involved H5N6 in wild birds. In Germany, veterinary officials reported the virus in a white stork found dead on Apr 28 in Lower Saxony state in the country's northwest. The last German H5N6 outbreak occurred in the middle of March in backyard birds in Schleswig-Holstein state. In Japan, the virus was found in two large-billed crows found dead on Mar 18 and Mar 25 in the city of Itami in Hyogo prefecture. The virus was linked to crow deaths that occurred in early March in the same city.

Elsewhere, Saudi Arabia reported seven more H5N8 outbreaks in poultry that started from Feb 20 to Mar 30 at different farms in Riyadh province. The virus killed 11,336 of 3,022,731 susceptible birds among the seven outbreaks, and authorities culled the remaining poultry to control the spread of the virus. Saudi Arabia has reported a small but steady stream of H5N8 outbreaks since the end of 2017.

In Taiwan, the agriculture ministry reported two more H5N2 outbreaks on commercial poultry farms. One began at a duck farm in Pingtung County on Apr 17 and the other started at a goose farm in Yunlin County on Apr 20. Taken together, the virus killed 545 of 6,204 birds, and the remaining poultry were culled as part of the outbreak response.
Apr 30 OIE report on H5N6 in Germany
Apr 27 OIE report on H5N6 in Japan
May 1 OIE report on H5N8 in Saudi Arabia
May 1 OIE report on H5N2 in Taiwan