Parasite Infection as a Treatment for Crohn's Disease

A new paper suggests that patients with intestinal disorders, such as Crohn's disease or inflammatory bowel disease (IBS), would gain from infection with intestinal parasites.Julius Lukes, one of the co-authors of the paper, and other scientists in the Canadian Institute for Advanced Research (CIFAR) Integrated Microbial Biodiversity program have begun to focus on eukaryotes which live within the human body in recent years - what they are calling the "eukaryome". Lukes asserts that most parasites are not harmful to otherwise healthy patients with low parasite loads. To prove his point, he ingested several eggs of Diphyllobothrium latum (picture below), a tapeworm commonly acquired by eating under-cooked fish. After a year, the parasites are estimated to be 12 feet in length, and Julius reports he is feeling fine.

The theory behind the deliberate infection of these patients with parasites is an extension of the "Old Friends Hypothesis", which is based on the idea that they evolved with us and have been inside humans for most of our history. These parasites, which include hookworms, tapeworms, and Blastocystis species, are thought to "distract" the immune system and prevent it from overreacting to normal stress and reducing inflammation in the intestines. These parasites are commonly thought to cause vitamin deficiency, anemia, and diarrhea, but Lukes says that a critical review of the evidence shows "no negative impact in well-nourished people with low overall parasite loads". The hypothesis is still in the early stages of testing, but similar strategies have worked for viral infections.

Sources

Article: http://www.medicalnewstoday.com/releases/280085.php

Picture: http://www.cdc.gov/parasites/images/diphyllobothrium/home_page_image_diphyllobothrium.jpg

Cryptococcus gattii in the Pacific Northwest

Cryptococcus gattii is a tropical fungus which causes severe neurological disease in those it infects. In 1999, C. gattii was isolated on Vancouver Island, British Columbia, Canada. In Canada, the fungus evolved into a virulent pulmonary form which has caused dozens of deaths. Since 1999, C. gattii has spread to mainland Canada, Washington state, and Oregon. In Oregon, a new strain of C. gattii was discovered which has increased lethality. This strain has spread through the Pacific Northwest.

These new strains of C. gattii  have been investigated by a team from the Translational Genomics Research Institute (TGen), led by David Engelthaler, Director of Programs and Operations. This team contained 24 researched from 13 institutions in 7 nations. They sequenced 115C. gattii genomes from 15 countries. Their results, published in the journal mBio, identify "several genes that may make the outbreak strains more capable of surviving colder environments and that make it more harmful in the lungs". These genes are also possible targets for new diagnostic tests, therapeutic drugs, or preventative vaccines. This study also "provide[s] evidence that the Pacific Northwest strains originated from South America", most likely originating from Brazil.

The study, "Cryptococcus gattii in North American Pacific Northwest: whole population genome analysis provides insights into species evolution and dispersal", warns that the virus is easily adaptable to new environments and warrants public heath vigilance, even in areas where C. gattii is not thought to be endemic.

Source: http://www.medicalnewstoday.com/releases/279696.php
Image: http://www.cdc.gov/fungal/images/cryptococcus-gattii-lifecycle.jpg

A New Rapid Test for Detecting Multi-Drug Resistance

One of the major complications of treating bacterial infections is the potential for multi-drug resistant (MDR), extensively drug-resistant (XDR), or pan-drug-resistant (PDR) organisms. Multi-drug resistance is defined as "non-susceptibility to at least one agent in three or more antimicrobial categories", XDR is defined as "non-susceptibility to at least one agent in two or fewer categories", and PDR is defined as non-susceptibility to all agents in all antimicrobial categories" (1). Fortunately, XDR and PDR organisms are much fewer in number than MDR organisms. However, antimicrobial resistance has increased dramatically over the past 20 years, particularly in regards to gram-negative rods, and broad-spectrum antibiotics such as cephalosporins and carbapenems (which used to be last-resort options) are now losing their efficacy.

A new rapid test, CarbAcineto NP, has been developed by Patrice Nordmann and Laurent Poirel which detects the presence of carbapenemase in Acinetobacter baumanii. This test detects "the acidification properties generated by the enzymatic hydrolysis of a carbapenem, imipenem, when it is cleaved by a carbapenemase". The acid produced by the breakdown of imipenem causes a pH indicator to turn from red to yellow. Either isolated bacteria or swabs of a site infection can be used in the test, which produces results in less than 2 hours, much faster than the 24-72 hours required for current methods. This new rapid test allows treatment decisions to be made much more quickly and effectively, as well as allowing for the identification of potential MDR organisms as a screening tool.

Article Sources
(1): http://www.ncbi.nlm.nih.gov/pubmed/21793988
Article: http://www.sciencedaily.com/releases/2014/06/140626095705.htm
Image: http://bacteriasactuaciencia.blogspot.com/2013/10/esperanza-en-la-lucha-contra.html

Biofilms and Catheters

Biofilms are formed by many bacteria, some that are harmful and some that are not. These films are slimy coatings that protect bacteria against antibiotics, our immune systems, cleaning agents, and other environmental dangers. In hospitals, biofilms that form inside catheters or around implanted medical devices can lead to infections, especially from Staphylococcus aureus. 

Researchers at Princeton University were able to observe how biofilms form within small tubes such as catheters. Typically, biofilms build up into thick layers on surfaces. In flowing liquids, biofilms for string-like filaments that float within the fluid. The researchers were first able to observe filament formation in a solution of Pseudomonas aeruginosa. Filaments formed by P. aeruginosa took around 50 hours to clog the tubing. When researchers repeated the experiment with S. aureus, the tubes clogged within a few hours. They then coated the tubes with plasma to imitate how the organism would act within an intravenous catheter. These tubes were clogged in a few minutes.

Howard Stone, a Princeton researcher, says he is unsure how the organism is able to form these filaments so quickly, but the knowledge will assist with designing medicals tools and devices that are more resistant to colonization. Stone also pointed out that the concentrations of bacteria used in the experiments was much higher than those typically found inside medical devices. Breaking up the biofilms and preventing them from forming could be the next step in treatment of these organisms.

Source: http://www.npr.org/blogs/health/2014/06/27/325502998/sticky-streamers-of-staph-bacteria-may-clog-up-medical-devices

MERS

MERS, or Middle Eastern Respiratory Syndrome, is a viral illness which appeared in Saudi Arabia in 2012. MERS is a coronavirus, similar in structure to rhinoviruses which cause the common cold and SARS. The first symptoms of MERS are fever, cough, and shortness of breath. Since 2012, MERS has spread across the Middle East, and has been found in camels in Qatar, Oman, and Egypt in addition to Saudi Arabia. The exact source of the infection is unknown, but camels are a strong suspect.  MERS cases outside the Middle East are associated with travel, and are not endemic. According to the World Health Organization (WHO), there have been 820 cases of MERS and 286 deaths. Saudi Arabia has reported 113 cases and 34 deaths. Currently, there is no vaccine available for MERS.

Reports of MERS cases began to increase in March of this year, but has begun to decrease again. However, some scientists at WHO are concerned that the annual pilgrimage (Hajj) to Saudi Arabia in October will further increase its spread. Currently, MERS does not easily spread from person-to-person (most cases are spread camel-to-person), but the increased number of people exposed to camels in the coming months could allow the virus to mutate. Saudi Arabian health officials say they have increased surveillance and infection control measures in anticipation of the Hajj.

Resources
http://www.nbcnews.com/storyline/mers-mystery/mers-outbreak-could-spread-annual-pilgrimage-officials-n132866
http://www.cdc.gov/coronavirus/mers/faq.html
http://www.bbc.com/news/health-28044151

Making Blood Culture Workups More Efficient

A major problem with blood culture workups is that it is often difficult to determine a true positive (pathogen) result from a false positive (contaminant) result. One solution is to adjust the testing algorithm in place. In 1970, it was shown that 11% of contaminated cultures had additional positive cultures, while 69% of clinically significant cultures had multiple positive cultures. In the proposed algorithm (summarized right), any
isolates that are typically contaminants that are not present in follow-up cultures are reported as contaminants. To confirm the accuracy of the new algorithm, a nurse epidemiologist and an infectious diseases physician reviewed the patient charts.

Overall, organisms considered to be contaminants (CNS, diphthroids, Micrococcus spp, Bacillus spp, and viridans streptococci) were identified in 495/1040 positive blood cultures. Of the 495, 286 were classified as contaminants due to negative follow-up cultures, 171 were investigated by a pathology resident, and 15 were classified as pathogens (viridans strep with positive follow-up cultures). The majority (62%) of the contaminants were identified as CNS.

Two types of errors, VM (very major) and M (major) were used to determine the success of the new algorithm. A "very major error" occurred if an isolate that was classified as a contaminant was determined to be clinically significant after chart review. A "major" error occurred if an isolate was classified as indeterminate or pathogenic and was later determined to be not clinically significant. VM errors occurred in 6.3% of cases and M errors occurred in 6.6% of cases. Further adjustment of this algorithm may decrease the error rate in the future, but the algorithm was determined "acceptable" by the authors of this study.

Source: http://jcm.asm.org/content/40/7/2437.full

PED Virus Increasing Pork Prices

In May 2013, porcine epidemic diarrhea virus (PEDv) was isolated in hog herds in the United States. PEDv cause diarrhea and vomiting in pigs (morbidity near 100%) with variable mortality. Older pigs are more likely to survive the virus than young pigs (mortality 50-100%). The virus has an incubation period of 3-4 days, and is spread more slowly than other types of swine gastroenteritis. Pigs who recover do so within 7-10 days of symptom onset. The virus is spread through a fecal-oral route, but fomites and contaminated equipment may spread the virus as well.

PEDv was first reported in the United Kingdom in 1971, and has spread to several countries since then.
PEDv is a Coronavirus, containing an enveloped ssRNA genome. The virus does not appear to have jumped to humans in the 40 years since its discovery.

Global AgriTrends speculates that up to 4.5% of pigs, or 4.5 million hogs, in the US may be killed by PEDv this year. Some farms have lost 10% of their herds already. Pork prices are expected to increase 3% this year, compared to 0.9% last year. A vaccine is not yet available for the virus in the US, but there are vaccines currently available in South Korea, Japan, and China.