Household pets can transmit infection to people, especially those with weak immune systems, young children, pregnant women and seniors, according to a new study. Health care providers and pet owners should be aware of this risk to prevent illness in vulnerable people.

Surveys suggest that the general public and people at high risk for pet-associated disease are not aware of the risks associated with high-risk pet practices or recommendations to reduce them; for example, 77% of households that obtained a new pet following a cancer diagnosis acquired a high-risk pet," states Dr. Jason Stull, assistant professor, Department of Veterinary Preventive Medicine, Ohio State University, Columbus, Ohio.

The immune-boosting properties of breast milk have long been known and experiments in mice are beginning to show another way how. A team of scientists led by Johns Hopkins pediatric surgeon-in-chief David Hackam, M.D., Ph.D., says their experiments reveal how breast milk works to ward off the development of necrotizing enterocolitis (NEC), a devastating intestinal disorder that affects 12 percent of premature babies and claims the lives of one in four of those who have it.

If affirmed in human studies, the experiments could pave the way to new preventive approaches to stave off NEC in premature babies and spark the development of treatments for those who develop the condition.

Following a first seizure, physicians should discuss with patients whether it is appropriate to prescribe medication to reduce risk of another seizure, according to new guidelines released at the latest American Academy of Neurology meeting. 

Human tumors grown in mouse models have long been used to test promising anti-cancer therapies. However, when a human tumor is transplanted into a mouse, the mouse immune system must be knocked down so that it doesn't attack the foreign tumor tissue, thus allowing the tumor to grow. A University of Colorado Cancer Center study describes a new model, XactMice, in which human blood stem cells are used to grow a "humanized" mouse immune system prior to tumor transplantation.

As the search continues for Earth-size planets orbiting at just the right distance from their star, a region termed the habitable zone, the number of potentially life-supporting planets grows. In two decades we have progressed from having no extrasolar planets to having too many to search. Narrowing the list of hopefuls requires looking at extrasolar planets in a new way.

But Tau Ceti already doesn't make the cut.

A new study provides a possible explanation of reports that mothers of twins are more likely to have smoked, despite evidence that nicotine reduces fertility.

Nicotine has an effect on hormone production, and while smoking may have deleterious effects on fertility, the study found that it may raise the likelihood of producing twins in women with certain genetic backgrounds. The researchers discovered significant interactions between smoking and variants in several genes, especially one in the TP53 gene.