If parents smoke, there is an increased likelihood that their children carry potentially virulent strains of bacteria that cause respiratory and ear infections and meningitis, according to a new study carried out at Soroka Hospital in Beersheba. Passive (sidestream) smoking increases the carrier rate in exposed children to Streptococcus pneumoniae. An article describing the study as well as an accompanying commentary have just been published in the on-line edition of the prestigious journal Clinical Infectious Diseases; it will appear in the print edition on April 1. These bacteria are the main cause of ear infections, pneumonia and infection in the blood, and among the leading causes of infections of the meninges - the tissue covering the brain. The research team, headed by Soroka pediatrician and infectious disease expert Dr. David Greenberg, his colleague Dr. Noga Givon-Lavi and others at Ben-Gurion University of the Negev and Clalit Health Services, also reported that smoking mothers were significantly more likely than nonsmoking mothers to carry these virulent bacteria in their own bodies. The researchers expressed the hope that their findings would convince parents to stop smoking, at least when they are around children. "Smoking parents, especially smoking mothers - or the parent spending the most time with the child - jeopardize their children's health" by putting them at higher risk for invasive and respiratory infections, Greenberg said. "This should definitely encourage the parents not to smoke in the presence of their child, especially if this child has predisposing factors such as asthma," he said. Streptococcus pneumoniae is often present in the nose and throat, and children are more likely to carry it than adults. If the bacteria, also called pneumococci, multiply wildly out of control, infection can result, leading to minor illnesses such as ear infections, or to more serious diseases like sinusitis, pneumonia and meningitis. The Beersheba team studied 208 children aged one month to five years and their mothers at primary health care clinics in two Jewish and two Beduin towns in the south. They used swabs to take samples from the subjects noses and throats, to find out how many carried these bacteria, and then correlated the data with the children's and mothers' exposure to smoking. Forty-five percent of the children had two nonsmoking parents. Pneumococcal carriage was 16 percent higher in children with exposure to smoking than in those not exposed. Exposed children were also more likely to carry pneumococcal serotypes responsible for most invasive Streptococcus pneumoniae disease. Differences were also noted among the mothers: 32% of mothers who smoked carried S. pneumoniae, compared with 15% of mothers who were exposed to second-hand smoke and 12% of mothers who were not exposed to smoking. Greenberg said that higher carriage rates of these pathogenic bacteria could translate into higher rates of infection. "Since carriage in the nose is the first step in causing disease, the increased rate of carriage suggests more frequent occurrence of the disease. Indeed, active and passive smoking are associated with increased rate of respiratory infectious diseases," he said. The team also found that nonsmokers carried more anaerobic bacteria, which do not need oxygen to exist and actually interfere with the disease-causing bacteria in the nasal passages and throat. The accompanying editorial commentary by Dr. Timothy Murphy of the University of Buffalo's Veterans Affairs Medical Center pointed to the higher incidence of ear infections in children of smokers, a phenomenon that could be explained in part by the findings of the Israeli study. Murphy praised the Israeli researchers for "making an important contribution to further our understanding of the epidemiology and pathogenesis" of middle-ear infection. The team's linkage between smoking and an increased rate of pneumococcal colonization in smoking mothers and their children explained, at least in part, the higher incidence of middle-ear infection in the children of smoking parents, Murphy wrote. Founded in 1979, Clinical Infectious Diseases publishes twice monthly on a variety of areas of infectious disease and is one of the most highly regarded journals in the field. It is published under the auspices of the Infectious Diseases Society of America - a professional society based in Alexandria, Virginia, that represents about 8,000 physicians and scientists who specialize in infectious diseases. In other news, the Israel Cancer Association commented on a new British survey published in Auto Trader magazine that found two-thirds of drivers favored prohibiting smoking while driving. The ICA said that such an initiative was already under way in Israel, as the association's chairman, Prof. Eliezer Robinson, had called on Transportation Minister Meir Sheetrit to initiate legislation of such a ban. Drivers who smoke are 50% more likely to be involved in accidents than nonsmoking drivers.