News Scan for Nov 15, 2016

News brief

Groups unveil new leishmaniasis treatment guidance  

The Infectious Diseases Society of America (IDSA) and the American Society of Tropical Medicine and Hygiene (ASTMH) released new guidelines for treating leishmaniasis, a parasite transmitted through bites from sand flies and on the rise in American tourists and military personnel serving in Iraq and Afghanistan.

The guidelines were published in the journal, Clinical Infectious Diseases, and include rapid diagnostic tests and innovative treatments to treat the infection, which most commonly causes skin scabs and sores (cutaneous leishmaniasis [CL]). When CL spreads to mucous membranes, it is called mucosal leishmaniasis (ML), and can cause deformity and scarring if left untreated. Not treating leishmaniasis can lead to visceral leishmaniasis (VL), a deadly, systemic infection.

According to the new guidelines, doctors should ask patients showing symptoms of the bites or scabs if they have recently traveled outside the United States, especially to South America or the Middle East. Blood tests can help diagnose, and oral miltefosine, approved by the FDA in 2014, can treat all three types of leishmaniasis.

The parasite is found in 90 countries around the world, but not commonly in the United States. Many doctors are unfamiliar with the clinical symptoms of leishmaniasis. There is no vaccine for leishmaniasis, but the guidelines say travelers can avoid the sand fly bites by wearing protective clothing and using insect repellent with DEET.
Nov 14 Clin Infect Dis article
Nov 15 IDSA press release

  

West Nile virus deadlier than previously thought

A new study presented today at the 2016 Meeting of the American Society of Tropical Medicine and Hygiene (ASTMH) suggests that previous infection with West Nile virus (WNV) could shorten a patient's lifespan and raise WNV's mortality rate from 4 % to 13%.

Researchers from the Baylor College of Medicine looked at 4,144 WNV infections in Texas from 2002 to 2012. In the initial 90 days post-infection, 286 people died, but another 268 people died within a 10-year period due to West Nile neuroinvasive disease and other complications. That means WNV has an acute mortality rate of 4%, but another 10% of patients will eventually die from their infections. This is the first population-level evidence of acute and delayed mortality among patients with a history of WNV infection.

Delayed deaths were more common in patients who reported severe neurological complications, and kidney disease was a statistically significant cause of death in the patients with delayed mortality. The risk was most significant in patients under the age of 60.

WNV is transmitted by mosquitoes, and first appeared in the United States in 1999. Like Zika virus, WNV is a flavivirus that could have longer, more serious health consequences than previously thought.
Nov 14 ASTMH abstract
Nov 14 ASTMH press release

 

Big data could impact infectious disease surveillance

Big data derived from the internet, including electronic health records and social media, may change the surveillance methods of infectious disease outbreaks and threats, according to a special issue of the Journal of Infectious Diseases (JID).

A team of scientists from the National Institutes of Health (NIH) analyzed recent uses of Big Data to establish how and when using the information could be helpful in infectious diseases surveillance.

The researchers say that while traditional public health institutions have established ways to gather data on disease outbreak and illness, Big Data offers a chance for a speedier, "real time" information gathering process. The contributors to the special issue of JID observed three Big Data "streams" of information: electronic health records, crowd-source data from people self-reporting symptoms, and social media. These streams may be particularly helpful in low-income countries where traditional public health surveillance capabilities are lacking or strained.

The JID issue contains articles that look at using Big Data to track influenza, antibiotic resistance, and Ebola. Researchers also investigate how insurance companies working with digital claims can help track disease outbreaks and fill in knowledge gaps.

"The ultimate goal is to be able to forecast the size, peak, or trajectory of an outbreak weeks or months in advance in order to better respond to infectious disease threats. Integrating big data in surveillance is a first step toward this long-term goal," said Cecile Viboud, PhD, co-editor of the supplement and a senior scientist at the NIH's Fogarty International Center, in a press release yesterday from the NIH.
J Infect Dis special issue
Nov 14 NIH press release

 

Household meningitis transmission patterns in Africa

A new study in The Lancet Global Health says that in countries along Africa's meningitis belt, 25% of household contacts of people who carry meningococci also tested positive for the bacteria.

This is the first longitudinal study to assess meningococcal carriage in Chad, Ethiopia, Ghana, Mali, Niger, Nigeria, and Senegal, an area known as Africa's meningitis belt. Researchers looked at 980 residents within 4 weeks of identifying a household carrier. Through swabs of the pharynx and tonsils, they found that at least 25% of contacts carried the bacteria for an average of 3 months. Children under the age of 5 were more likely to carry bacteria than other contacts.

The study was aimed to better understand meningitis carriage after the introduction of the new serogroup A meningococcal conjugate vaccine, MenAfriVac (Serum Institute of India PVT, Pune, India). According to the study, 20 cross-sectional carriage surveys were conducted between 2010 and 2012.

"Our findings indicate that substantial spread of meningococci occurs within households so that prophylaxis of household contacts after a case of meningococcal meningitis, recommended policy in the meningitis belt outside epidemics, could be given greater priority," the authors concluded.
Nov 14 Lancet Glob Health study

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