NEWS SCAN: Listeria cases rise, novel tickborne illness, polio risk from Pakistan, rotavirus vaccine benefits, new transplant guidelines, mumps antibodies

Sep 21, 2011

Cases in widespread Listeria outbreak jump to 55; death toll reaches 8
The number of reported cases in the current multistate Listeria outbreak tied to cantaloupe has increased by 20 in the past 2 days, to 55, and the number of deaths has doubled, to 8, the Centers for Disease Control and Prevention (CDC) announced today. The number of affected states has risen to 14, four more than reported on Sep 19. The deaths include 4 in New Mexico, 2 in Colorado, and 1 each in Maryland and Oklahoma, the CDC reported. Most of the patients have been older than 60, and of 43 patients for whom information was available, all were hospitalized. Colorado officials reported previously that Listeria monocytogenes isolates found in cantaloupe samples from a sick patient's home and from retail outlets matched the strain found in some patients. The CDC said four Listeria strains have been identified in the outbreak. The implicated cantaloupes came from Jensen Farms in Colorado, which on Sep 14 recalled all cantaloupes distributed between Jul 29 and Sep 10.
Sep 21 CDC update

Novel tickborne illness in Russia could turn up in US, study says
Scientists say a novel Lyme disease–like illness that is spread by ticks in Russia could also occur in the United States, because the bacterium that causes it is also found in parts of the US. The febrile illness is caused by Borrelia miyamotoi, which was discovered in Japan in 1995, according to a report by Russian and US scientists in Emerging Infectious Diseases. B miyamotoi is related to B burgdorferi, the cause of Lyme disease, also spread by ticks. Saying their report is the first to clearly document the illness in humans, the scientists reported 46 cases of B miyamotoi infection in patients who were treated at a hospital in Yekaterinburg, Russia, in the summer of 2009. The patients had an influenza-like illness, which was treated successfully with antibiotics, but five of them had relapsing fever. The authors say B miyamotoi has been found in 1% to 16% of Ixodes persulcatus ticks in Russia, and about 15% of spirochetes (spiral bacteria) carried by I scapularis (deer) ticks in the northeastern United States are B miyamotoi. They assert that undiagnosed cases may occur in the US because the illness could be mistaken for Lyme disease or other tickborne infections such as babesiosis. Two American members of the research team recently won a federal grant to study the disease and develop a diagnostic test, the New York Times reported. In a posting yesterday on ProMED, the disease reporting service of the International Society for Infectious Diseases, a moderator commented that another similar disease, classical tickborne relapsing fever, is already present in the western US.
Sep 20 Emerg Infect Dis report

WHO cautions on high risk of polio spread from Pakistan
The World Health Organization (WHO) yesterday rated the risk of spread of polio from Pakistan as "high" after wild poliovirus type 1 (WPV1) genetically linked to polioviruses circulating in Pakistan was isolated in China earlier this month. The agency cited widespread transmission of WPV1 within Pakistan and the occurrence there of this year's only Asian case of WPV3 as other factors. As of Sep 13, Pakistan had confirmed 84 polio cases this year, up from 48 for the same period last year. The WHO also said that expected mass travel for Umrah and hajj pilgrimages to Mecca increase the risk of disease spread and that Saudi Arabia is mandating polio vaccination for pilgrims. The agency said that Pakistan's increased immunization efforts this year have not completely succeeded. On Sep 1 the WHO reported WPV1 cases in four young Chinese children from Xinjiang province (which borders Pakistan) that were genetically linked to WPV1 in Pakistan and were the first polio cases in China in 12 years. And yesterday the BBC said "at least seven" cases from the province in the past two months have been linked to Pakistan.
Sep 20 WHO alert
Sep 1 WHO report on Chinese cases
Sep 20 BBC article
In related news, Kenya reported three WPV1 cases in young children, according to the UN's IRIN News service. The virus was detected in three children in the Kamagambo area of Rongo District in western Kenya. "Even if one case is detected, it is considered an outbreak as the virus can spread really fast," said public health director Shahnaaz Sharif. The strain is similar to one found in Uganda in 2010, according to Sharif. A massive immunization effort is planned for the region.
Sep 19 IRIN News story

CDC study links rotavirus vaccine to fewer clinic visits, cost savings
A study from a large US insurance database estimates that rotavirus vaccination decreased the number of hospitalizations of children under age 5 by 65,000 from 2007 to 2009, saving about $278 million in healthcare costs. The researchers from the Centers for Disease Control and Prevention (CDC) reported their findings today in the New England Journal of Medicine (NEJM). Their analysis of data from 2001 through 2009 assessed doctor's visits, emergency department visits, hospitalizations, and deaths both before and after the vaccine was introduced in 2006. The group also estimated the indirect protective benefits to unvaccinated kids and calculated declines in treatment use and costs by extrapolating the declines they saw in the study to children younger than 5 in the US population. Rotavirus-related hospitalizations declined substantially from prevaccination levels, decreasing by 75% for 2007-08 and 60% for 2008-09. Declines were even seen in unvaccinated youngsters during the 2008 rotavirus season, the authors reported. Dr Mark Pallansch, who directs the CDC's Division of Viral Diseases, said in a statement that the study adds to the body of evidence showing rotavirus vaccination can reduce illnesses and costs. "As more children get vaccinated against rotavirus, we expect to see even greater reductions in disease among all age groups," he said.
Sep 21 NEJM abstract
Sep 21 CDC press release

New CDC guidelines on organ transplants call for hepatitis screening
The CDC today released new draft guidelines on organ transplants that call for more thorough donor screening and improved organ testing to protect transplant recipients from infections. The guidelines recommend adding hepatitis B and C viruses (HBV and HCV) to the screening program, which already includes HIV. The CDC said it was involved in more than 200 investigations of suspected transmission of HIV, HBV, and HCV via transplants from 2007 through 2010. A group of transplant and infection prevention experts systematically reviewed the evidence to develop the new guidelines. In addition to HBV and HCV screening, the guidelines call for more sensitive lab tests for organs and provide a revised set of donor risk factors. The recommendations focus only on solid organs and vessel conduits, the CDC said, nothing that the Food and Drug Administration has implemented more comprehensive regulations for tissue and semen donors. The CDC is inviting comments on the draft guidelines for 60 days.
Sep 21 CDC press release

Study: Students who had mumps had lower pre-outbreak antibodies
University students who contracted mumps in a 2006 outbreak had lower levels of pre-outbreak mumps antibodies in their blood compared with other students, but the levels did not clearly differentiate them from non-patients, according to a study in the Journal of Infectious Diseases. Researchers analyzed blood from 11 case-patients, 22 non-patients who reported mumps exposure but had no symptoms, and 103 non-patients who reported no exposure or symptoms. They found that patients had Jeryl Lynn virus neutralization titers significantly lower than those in unexposed non-patients (P = .023) and enzyme immunoassay results significantly lower than exposed non-patients (P = .007) and unexposed non-patients (P = .009). The authors conclude, "Case patients generally had lower preoutbreak mumps antibody levels than non-patients. However, titers overlapped and no cutoff points separated all mumps case patients from all nonpatients."
Sep 20 J Infect Dis abstract

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