CDC reports 3 variant flu cases, with possible human-to-human spread in 1
The US Centers for Disease Control and Prevention (CDC) today reported three new infections involving novel influenza A viruses, two of them variant H3N2 (H3N2v) and one variant H1N2 (H1N2v), with possible human-to-human transmission in one of the cases.
The H3N2v cases were in Nebraska and Michigan, the first for Nebraska and the second in Michigan. The Michigan case involves a person who had close contact with the only other H3N2v case-patient this year. The newly reported patient also had swine exposure, but it was more than a week before symptoms began, so the contact was outside the typical incubation period.
"It is possible that limited human-to-human transmission occurred," the CDC said. "No ongoing human-to-human transmission has been identified." The CDC said in background material on variant flu viruses that limited person-to-spread has occurred before.
The H3N2v patient in Nebraska reported no contact with swine the week before falling ill, but a member of the same household did report recent swine exposure. The CDC has confirmed 61 H3N2v cases so far this year, which is a bit of a surge. The previous 4 years saw from only 3 to 19 cases per year, with 2012 being a huge year for the strain, with 309 H3N2v cases confirmed.
The H1N2v case in Colorado is just the fourth infection involving that strain this year. The others were in Ohio patients. The Colorado patient reported being exposed to swine at an "agricultural event" the week preceding illness onset. Many of the variant flu cases reported this year have involved contact with swine at fairs.
Nov 3 CDC FluView update
CDC background material on variant flu viruses
Survey details spread of livestock-associate MRSA in Europe
Results from a survey published yesterday in Eurosurveillance indicate more frequent detection and greater geographical dispersion of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) in Europe.
The survey and questionnaire from the European Centre for Disease Prevention and Control (ECDC) collected data on LA-MRSA subtypes identified among MRSA isolates by national or regional reference laboratories in European Union/European Economic Area (EU/EEA) countries in 2013. The samples included both clinical and screening isolates. Overall, 28 reference labs (26 national and 2 regional) from 27 of 30 EU/EEA countries responded.
The respondents reported receiving MRSA isolates from 14,291 patients in 2013, of which 13,756 (96.3%) were molecularly typed. LA-MRSA was identified by 17 of 19 countries (89%) with MRSA typing data. The Netherlands, Denmark, and Spain reported the most LA-MRSA isolates (164, 157, and 52, respectively). The overall percentage of typed MRSA isolates that were LA-MRSA was 3.9% (535 of 13,756).
Almost all LA-MRSA isolates belonged clonal complex (CC) 398, which is commonly associated with swine and is the most widespread MRSA lineage in Europe. The only non-CC398 subtype considered to be LA-MRSA came from Italy.
This was the first survey conducted on LA-MRSA in the EU/EEA since 2007, when only eight countries reported LA-MRSA isolates from human; in that survey, the proportion of MRSA that were LA-MRSA was above 2% in four countries and one region of Germany. The authors of the current study say the 2013 survey results, along with more recent data suggesting that LA-MRSA is spreading in the Nordic countries, the Netherlands, Germany, and the UK, indicate an apparent upward trend and more widespread dispersion of LA-MRSA across Europe. They're also concerned that labs in seven of the responding countries did not report any MRSA typing.
The ECDC is recommending that EU/EEA countries repeat the survey periodically to monitor for changes and map potential reservoirs and transmission pathways.
Nov 2 Eurosurveill report
Nov 3 ECDC news release
New polio cases detected in Afghanistan, Syria, DRC
In its weekly update, the Global Polio Eradication Initiative (GPEI) described two cases of wild poliovirus in Afghanistan as Syria and the Democratic Republic of Congo (DRC) each reported a new case of vaccine-derived polio.
The first case in Afghanistan was announced last week in an advance notice. The patient is a girl, age 8 months, in Afghanistan's Kandahar province. The baby's onset of paralysis was Oct 2. She had no previous vaccination against poliovirus. Next week, the GPEI will report the details of another wild poliovirus case in Nangarhar province, Afghanistan, the organization said in the update. Onset of paralysis for that case was Oct 11.
Both Syria and the DRC reported a case of vaccine-derived polio. There have now been 53 cases of vaccine-derived polio in Syria this year. The latest involves a 15-month-old child from Mayadin district, Deir ez-Zur governorate. The child had received one dose of oral polio vaccine and no doses of injected polio vaccine.
In DRC, a patient who had symptom onset on Sep 14 was diagnosed as having type 2 vaccine-derived polio. This is the tenth case of vaccine-derived polio in DRC this year.
Nov 1 GPEI report
French Guiana study finds 77% of pregnant women with Zika symptom-free
A study of Zika-infected pregnant women in French Guiana published yesterday in Eurosurveillance found that 77% were symptom-free, but with wide variations among different populations.
The study did not look at the effects of Zika infection on the women's fetuses or babies.
The researchers, from French Guiana and France, enrolled 3,050 girls and women aged 14 to 48 who were pregnant from Feb 1 to Jun 1, 2016. Of those, 573 (19%) had lab-confirmed Zika virus (ZIKV) infection. Among the 23% who reported at least one symptom consistent with ZIKV, the most common symptoms were rash, joint pain, muscle aches, and conjunctival hyperemia (eye redness).
The rate of symptomatic infections varied from 28% in those 30 and older to 20% in younger women and girls, a statistically significant difference. In addition, the proportion of symptomatic infections varied from 17% in the remote interior to 35% in the urban population near the Atlantic coast.
The authors conclude, "These estimates put findings on cohorts of symptomatic ZIKV-positive pregnant women into the wider context of an epidemic with mainly asymptomatic infections. The proportion of symptomatic ZIKV infections appears to vary substantially between populations."
Nov 3 Eurosurveill report