News Scan for Mar 19, 2014

Emerging tick-borne bacterium

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NYC measles outbreak

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Haemophilus influenzae in pregnancy

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Haemophilus influenzae

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Emerging tick-borne bacterium threatens immunocompromised patients

An emerging tick-borne bacterium in Europe, Asia, and Africa poses a risk for immunocompromised patients, causing an illness that could be mistaken for an underlying disease, according to a study published yesterday in Clinical Infectious Diseases.

The bacterium, widespread in ticks, rats, mice, and voles, was discovered in Japan in 2004 and was first recognized as a human pathogen in 2010, says the report by a European team. It is calledCandidatus Neoehrlichia mikurensis, with the first term signifying that no one has reported cultivating it as yet.

The authors gathered data on 11 European patients with hematologic malignances or autoimmune diseases in whom the infection was diagnosed from 2010 to 2013.

The patients were mostly older men (median age, 67); all but one had ongoing or recent immunosuppressive treatment, and 8 of 11 had undergone splenectomy, the report says. Less than half of them recalled tick exposure.

The most frequent symptoms were fever (in 11 of 11), pain in muscles and/or joints (8 of 11), vascular and thromboembolic events such as deep vein thrombosis (6 of 11), transitory ischemic attacks (2), pulmonary embolism (1), and arterial aneurysm (1).

The median time from first symptoms to correct diagnosis was 2 months. In at least four cases, the condition was attributed to the underlying disease, and immunosuppressive therapy was scheduled. All the patients recovered with doxycycline treatment.

The authors conclude that Ca Neoehrlichia mikurensis is "an emerging tick-borne pathogen that may give rise to a systemic inflammatory syndrome in persons with hematologic or autoimmune diseases that could be mistaken for recurrence of the underlying disease and/or unrelated arteriosclerotic vascular events. Awareness of this new pathogen is warranted among rheumatologists, hematologists, oncologists, and infectious disease specialists."
Mar 18 Clin Infect Dis abstract

NYC officials probing healthcare link in measles outbreak

A 20-case outbreak of measles that is concentrated in northern Manhattan might have been spread in medical facilities after healthcare workers failed to recognize the disease quickly enough and isolate infected patients, a New York City epidemiologist told the New York Times.

Jay K. Varma, MD, deputy commissioner for disease control in the New York City Department of Health and Mental Hygiene, said the department is investigating whether any of the cases resulted from exposure in healthcare facilities. The first outbreak case was detected in early February.

"We know a number of people were exposed and possibly got their infection either at a doctor’s office or at an emergency room where they went and it took more time than it should have for them to be put in an isolation area where they couldn’t possibly infect anyone else," Varma said.
Mar 18 New York Times article

In related news, California health officials said that 19 of 32 confirmed measles cases so far this year have been in patients who were not vaccinated, 14 of whom were intentionally not vaccinated, according to Southern California Public Radio (SCPR).

California allows parents to opt out of childhood vaccines if they fill out a personal belief exemption form and discuss the issue with a doctor, but state health authorities are urging parents not to go that route, fearing disease resurgence. At this time last year the state had confirmed only three measles cases.
Mar 18 SCPR story

UK study shows higher risk of H influenzae in pregnancy

Pregnancy was associated with a greater incidence of Haemophilus influenzae infections in UK women of reproductive age, and the disease was consequently linked to very high rates of premature births and stillbirths, according to a surveillance study today in the Journal of the American Medical Association (JAMA).

Researchers from Public Health England asked general practitioners who cared for girls or women 15 to 44 years old who had a lab-confirmed H influenzae infection from 2009 through 2012 to complete a questionnaire about 3 months after infection. With 171 infections reported, the overall risk was low: 0.50 per 100,000 women. Seventy-five of those patients were pregnant.

The vast majority of those cases—144, or 84%—involved unencapsulated strains, compared with 11 (6.4%) from serotype b and 16 (9.4%) from other encapsulated strains. The investigators found that the incidence of unencapsulated H influenzae disease was 17.2 times greater in pregnant women.

They also found that infection with unencapsulated strains during the first 24 weeks of pregnancy was associated with fetal loss in 44 of 47 women and extremely premature birth in the other 3. In the second half of pregnancy the infection was associated with 8 cases of premature birth and 2 cases of stillbirth among 28 women. Pregnancy loss following H influenzae disease was 2.9 times higher than the UK average.

The authors conclude, "The increased incidence of invasive H influenzae disease among pregnant women was reminiscent of Listeria monocytogenes infections but with a much higher rate of fetal loss."
Mar 19 JAMA study
Mar 19 JAMA editorial on the study
Mar 19 JAMA news release

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