News Scan for Jan 30, 2017

News brief

Two more H7N9 cases reported in China

Signaling an ongoing rise in H7N9 avian flu activity in China, the country's Liaoning province in the northeast today reported two cases, according to a local health department statement translated and posted today by FluTrackers, an infectious disease news message board.

No details were available about the two patients, other than that they are from different cities and that both are in stable condition. Provincial officials said they have designated a hospital for treating the patients. The cases appear to be the first from Liaoning province in the current H7N9 wave, which is the country's fifth.

China, which celebrated Lunar New Year over the weekend, reported an early large spike in H7N9 cases in December, and cases in January have already topped that level. An analysis of China's recent surge said one reason may be an increase in viral levels in poultry and their environments. Most cases occur in people who have contact with poultry.

Though a few small clusters have been reported, the virus doesn't spread easily among people, and no sustained human-to-human transmission has been reported.
Jan 30 FluTrackers thread

New MERS cases linked to camel exposure

The Saudi Arabian Ministry of Health (MOH) confirmed two new MERS-CoV cases over the weekend and said that a previously reported patient died from the respiratory illness.

On Jan 28 the MOH reported that two Saudis were in critical condition with symptoms of MERS-CoV (Middle East respiratory syndrome coronavirus). A 75-year-old man from Taif reportedly had direct contact with camels, while a 74-year-old woman in Al Khurma is listed as having indirect contact with camels. Exposure to camels, including drinking raw camel milk, has been cited as a risk factor for contracting MERS.

Yesterday the MOH reported the death of a 48 year-old foreign man in Jeddah. The patient had a preexisting illness.

The new cases raises Saudi Arabia's MERS-CoV total to 1,549 infections, including 642 deaths. Ten people are still in treatment or monitoring.
Jan 28 MOH report
Jan 29 MOH report

PAHO reports 1,400 new chikungunya cases in the Americas

As it begins a new year of tabulating chikungunya cases while continuing to update 2016 numbers, the Pan American Health Organization (PAHO) late last week added 1,439 new cases, 980 from 2016 and 459 from the first few weeks of this year.

The 980 cases from last year were in Bolivia, which has now reported a full 52 weeks' worth of 2016 data, according to a Jan 27 update e-mailed to CIDRAP News. The country closed the year with 21,977 confirmed, suspected, and imported cases, bringing the total number of 2016 cases in the Americas to 504,373.

So far in 2017, five countries have reported cases, led by Venezuela with 254, Colombia with 65, and Peru with 49. Of the 459 cases documented in 2017, 426 were noted in an updated posted on Jan 27 and 33 the week before.

The vast majority of countries, however, have not reported to the PAHO yet this year. And most countries are lacking full 2016 data, as well. Most notable among them is Brazil, which accounted for 82% of 2016 cases. It has not reported on the final 2 weeks of last year or on the first 4 weeks of this year.

The outbreak began in late 2013 on the Caribbean island of St. Martin and has now sickened at least 2,387,177 people.
Jan 27 PAHO update for 2017

Largest study of listeriosis shows high burden of disease

The largest prospective study of listeriosis, a foodborne pathogen, showed that infection with the bacterium can cause a high burden of disease, especially among pregnant women. The results were published today in The Lancet Infectious Diseases.

The MONALISA study took place in France, where listeriosis is a notable disease. The authors enrolled 818 eligible patients, who provided samples to the National Reference Center for Listeria from November 2009 to July of 2013. The cases included 107 maternal–neonatal infections, 427 cases of bacteremia, and 252 cases of neurolisteriosis.

One quarter (24%) of pregnant women experienced fetal loss if Listeria infection happened before 29 weeks of pregnancy, 45% experienced premature delivery, and 21% delivered a baby diagnosed with acute fetal distress (including fever, meconium contamination, or elevated heart rate). Only 5% of the documented pregnancies were unaffected by listeriosis.

Eighty-four percent of patients who had neurolisteriosis presented with meningoencephalitis. The authors found that only 39% of patients with neurolisteriosis survived and fully recovered, a higher percentage than reported in other studies.

In a comment on the study, Dutch experts said the data paint a grim picture of listeriosis. "Early diagnosis and treatment and standardised antibiotic regimens are needed to improve prognosis, but equally important is a better understanding of bacterial virulence and the pathophysiology of listerial disease."
Jan 30 Lancet Infect Dis study
Jan 30 Lancet Infect Dis commentary

Stewardship / Resistance Scan for Jan 30, 2017

News brief

Study shows possible benefit of azithromycin in pregnancy

Giving pregnant women a dose of azithromycin during labor reduces infections in both mothers and newborns, according to a new study in Pediatrics. But an accompanying commentary suggests the harms of azithromycin exposure could outweigh the benefits.

In a post-hoc analysis of a double-blind, placebo-controlled randomized trial, 829 Gambian women were given either an oral dose of azithromycin or a placebo. Investigators were looking to see whether the intervention had an effect on maternal and neonatal clinical infections such as sepsis, which is a high risk in sub-Saharan Africa because of poor nutrition and unhygienic delivery conditions. In Gambia, the authors note, neonatal deaths represent 40% of all deaths in children under the age of 5, and maternal mortality is among of the highest in the developing world.

Overall, the researchers found that maternal infections were lower in the azithromycin group than in the placebo group (3.6% vs. 9.2%), as was the prevalence of mastitis (1.4% vs. 5.1%) and fever (1.9% vs. 5.8%). The overall prevalence of infections was also lower among the newborns of the azithromycin group (18.1% vs. 23.8%), with a marked difference in skin infections (3.1% vs. 6.4%).

"Our results show that azithromycin administered to women in labor reduces maternal and neonatal infections and maternal episodes of fever," the authors write. "Larger trials designed to assess the effect of the intervention on severe morbidity and mortality are urgently needed."

But as noted in the accompanying commentary from two members of the American Academy of Pediatrics Committee on Infectious Diseases, the decrease in infections among the azithromycin group was driven primarily by mastitis in the mothers and skin infections in neonates, none of which were described as severe. In addition, no significant difference in rates of sepsis, malaria, hospitalizations, or deaths in mothers or infants were observed.

Furthermore, the commentary authors write, azithromycin exposure may facilitate the emergence of antimicrobial resistance, could alter the structure and function of the human microbiome, and has been associated with the development of hypertrophic pyloric stenosis in infants.

"In light of the small potential benefits observed in the Oluwalana study, the potential harms of azithromycin exposure likely outweigh the upside for this specific indication," the authors write. They suggest that future studies should assess azithromycin's effects on serious maternal and neonatal infections and evaluate potential harms.
Jan 27 Pediatrics study
Jan 27 Pediatrics commentary

Research highlights how antibiotics can stimulate bacterial reproduction

A study today in Ecology and Evolution shows that growth of bacteria can be boosted by antibiotics.

In the study, researchers from the University of Exeter in Great Britain were looking to determine the fitness costs associated with antibiotic resistance in Escherichia coli when exposed to the antibiotic doxycycline. Their working assumption was that the bacteria that acquired resistance mutations might proliferate more slowly.

To investigate, the researchers exposed E coli bacteria to eight rounds of antibiotic therapy over 4 days. As expected, the bacteria grew more resistant with each round of treatment. But what was unexpected was that the mutated E. coli reproduced faster after antibiotic exposure and formed much larger populations than bacteria exposed to no antibiotics. Furthermore, the ability to reproduce faster remained after antibiotic exposure ended.

"Our research suggests there could be added benefits for E.coli bacteria when they evolve resistance to clinical levels of antibiotics," lead author Robert Beardmore, BSc, said in a University of Exeter press release. "Bacteria have a remarkable ability to rearrange their DNA and this can stop drugs working, sometimes in a matter of days."
Jan 30 Ecol Evol study
Jan 30 University of Exeter press release